➕ Update vendor

vendor/github.com/visualfc/gotools/astview/astdoc.go

@@ -6,11 +6,13 @@
 package astview
 
 import (
+	"fmt"
 	"go/ast"
 	"go/token"
 	"regexp"
 	"sort"
 	"strconv"
+	"strings"
 )
 
 // ----------------------------------------------------------------------------
@@ -41,6 +43,7 @@ type docReader struct {
 	funcs   map[string]*ast.FuncDecl
 	imports map[string]int
 	bugs    []*ast.CommentGroup
+	todos   []*TodoDoc
 }
 
 func (doc *docReader) init(pkgName string, showAll bool) {
@@ -279,8 +282,10 @@ func copyCommentList(list []*ast.Comment) []*ast.Comment {
 }
 
 var (
-	bug_markers = regexp.MustCompile("^/[/*][ \t]*BUG\\(.*\\):[ \t]*") // BUG(uid):
+	todoList     = "TODO,BUG,FIXME,NOTE,SECBUG"
-	bug_content = regexp.MustCompile("[^ \n\r\t]+")                    // at least one non-whitespace char
+	bug_markers  = regexp.MustCompile("^/[/*][ \t]*BUG\\(.*\\):[ \t]*") // BUG(uid):
+	bug_content  = regexp.MustCompile("[^ \n\r\t]+")                    // at least one non-whitespace char
+	todo_markers = regexp.MustCompile(fmt.Sprintf("^/[/*][ \t]*(%s)[\\s\\:\\(\\,].*$", strings.Replace(todoList, ",", "|", -1)))
 )
 
 // addFile adds the AST for a source file to the docReader.
@@ -297,19 +302,21 @@ func (doc *docReader) addFile(src *ast.File) {
 	for _, decl := range src.Decls {
 		doc.addDecl(decl)
 	}
-
 	// collect BUG(...) comments
 	for _, c := range src.Comments {
 		text := c.List[0].Text
-		if m := bug_markers.FindStringIndex(text); m != nil {
+		if m := todo_markers.FindStringSubmatchIndex(text); m != nil {
-			// found a BUG comment; maybe empty
+			doc.todos = append(doc.todos, &TodoDoc{text[m[2]:m[3]], text[m[2]:], c})
-			if btxt := text[m[1]:]; bug_content.MatchString(btxt) {
-				// non-empty BUG comment; collect comment without BUG prefix
-				list := copyCommentList(c.List)
-				list[0].Text = text[m[1]:]
-				doc.bugs = append(doc.bugs, &ast.CommentGroup{list})
-			}
 		}
+		//		if m := bug_markers.FindStringIndex(text); m != nil {
+		//			// found a BUG comment; maybe empty
+		//			if btxt := text[m[1]:]; bug_content.MatchString(btxt) {
+		//				// non-empty BUG comment; collect comment without BUG prefix
+		//				list := copyCommentList(c.List)
+		//				list[0].Text = text[m[1]:]
+		//				doc.bugs = append(doc.bugs, &ast.CommentGroup{list})
+		//			}
+		//		}
 	}
 	src.Comments = nil // consumed unassociated comments - remove from ast.File node
 }
@@ -519,6 +526,12 @@ func makeBugDocs(list []*ast.CommentGroup) []string {
 	return d
 }
 
+type TodoDoc struct {
+	Tag      string
+	Text     string
+	Comments *ast.CommentGroup
+}
+
 // PackageDoc is the documentation for an entire package.
 //
 type PackageDoc struct {
@@ -532,6 +545,7 @@ type PackageDoc struct {
 	Vars        []*ValueDoc
 	Funcs       []*FuncDoc
 	Factorys    []*FuncDoc
+	Todos       []*TodoDoc
 	Bugs        []string
 }
 
@@ -553,6 +567,7 @@ func (doc *docReader) newDoc(importpath string, filenames []string) *PackageDoc
 	p.Vars = makeValueDocs(doc.values, token.VAR)
 	p.Funcs = makeFuncDocs(doc.funcs)
 	p.Bugs = makeBugDocs(doc.bugs)
+	p.Todos = doc.todos
 
 	for _, d := range p.Types {
 		switch d.Type.Type.(type) {

vendor/github.com/visualfc/gotools/astview/astview.go

@@ -9,14 +9,15 @@ import (
 	"go/ast"
 	"go/parser"
 	"go/token"
+	"go/types"
 	"io"
 	"io/ioutil"
 	"os"
+	"path/filepath"
 	"strings"
 
 	"github.com/visualfc/gotools/command"
-
+	"github.com/visualfc/gotools/pkgutil"
-	"golang.org/x/tools/go/types"
 )
 
 var Command = &command.Command{
@@ -27,9 +28,13 @@ var Command = &command.Command{
 }
 
 var astViewStdin bool
+var astViewShowEndPos bool
+var astViewShowTodo bool
 
 func init() {
 	Command.Flag.BoolVar(&astViewStdin, "stdin", false, "input from stdin")
+	Command.Flag.BoolVar(&astViewShowEndPos, "end", false, "show decl end pos")
+	Command.Flag.BoolVar(&astViewShowTodo, "todo", false, "show todo list")
 }
 
 func runAstView(cmd *command.Command, args []string) error {
@@ -73,6 +78,8 @@ const (
 	tag_type_method    = "tm"
 	tag_type_factor    = "tf"
 	tag_type_value     = "tv"
+	tag_todo           = "b"
+	tag_todo_folder    = "+b"
 )
 
 type PackageView struct {
@@ -99,8 +106,11 @@ func (p *PackageView) posFileIndex(pos token.Position) int {
 	return index
 }
 
-func (p *PackageView) posText(pos token.Position) (s string) {
+func (p *PackageView) posText(pos token.Position, end token.Position) (s string) {
 	index := p.posFileIndex(pos)
+	if astViewShowEndPos {
+		return fmt.Sprintf("%d:%d:%d:%d:%d", index, pos.Line, pos.Column, end.Line, end.Column)
+	}
 	return fmt.Sprintf("%d:%d:%d", index, pos.Line, pos.Column)
 }
 
@@ -156,7 +166,11 @@ func ParseFiles(fset *token.FileSet, filenames []string, mode parser.Mode) (pkgs
 
 func PrintFilesTree(filenames []string, w io.Writer, expr bool) error {
 	fset := token.NewFileSet()
-	pkgs, pkgsfiles, err := ParseFiles(fset, filenames, parser.AllErrors)
+	mode := parser.AllErrors
+	if astViewShowTodo {
+		mode |= parser.ParseComments
+	}
+	pkgs, pkgsfiles, err := ParseFiles(fset, filenames, mode)
 	if err != nil {
 		return err
 	}
@@ -182,7 +196,11 @@ func NewFilePackageSource(filename string, f *os.File, expr bool) (*PackageView,
 	p := new(PackageView)
 	p.fset = token.NewFileSet()
 	p.expr = expr
-	file, err := parser.ParseFile(p.fset, filename, src, 0)
+	mode := parser.AllErrors
+	if astViewShowTodo {
+		mode |= parser.ParseComments
+	}
+	file, err := parser.ParseFile(p.fset, filename, src, mode)
 	if err != nil {
 		return nil, err
 	}
@@ -200,10 +218,11 @@ func NewFilePackageSource(filename string, f *os.File, expr bool) (*PackageView,
 func (p *PackageView) printFuncsHelper(w io.Writer, funcs []*FuncDoc, level int, tag string, tag_folder string) {
 	for _, f := range funcs {
 		pos := p.fset.Position(f.Decl.Pos())
+		end := p.fset.Position(f.Decl.End())
 		if p.expr {
-			fmt.Fprintf(w, "%d,%s,%s,%s@%s\n", level, tag, f.Name, p.posText(pos), types.ExprString(f.Decl.Type))
+			fmt.Fprintf(w, "%d,%s,%s,%s@%s\n", level, tag, f.Name, p.posText(pos, end), types.ExprString(f.Decl.Type))
 		} else {
-			fmt.Fprintf(w, "%d,%s,%s,%s\n", level, tag, f.Name, p.posText(pos))
+			fmt.Fprintf(w, "%d,%s,%s,%s\n", level, tag, f.Name, p.posText(pos, end))
 		}
 	}
 }
@@ -224,11 +243,12 @@ func (p *PackageView) PrintVars(w io.Writer, vars []*ValueDoc, level int, tag st
 		for _, s := range v.Decl.Specs {
 			if m, ok := s.(*ast.ValueSpec); ok {
 				pos := p.fset.Position(m.Pos())
+				end := p.fset.Position(m.End())
 				for i := 0; i < len(m.Names); i++ {
 					if p.expr && m.Type != nil {
-						fmt.Fprintf(w, "%d,%s,%s,%s@%s\n", level, tag, m.Names[i], p.posText(pos), types.ExprString(m.Type))
+						fmt.Fprintf(w, "%d,%s,%s,%s@%s\n", level, tag, m.Names[i], p.posText(pos, end), types.ExprString(m.Type))
 					} else {
-						fmt.Fprintf(w, "%d,%s,%s,%s\n", level, tag, m.Names[i], p.posText(pos))
+						fmt.Fprintf(w, "%d,%s,%s,%s\n", level, tag, m.Names[i], p.posText(pos, end))
 					}
 				}
 			}
@@ -248,7 +268,8 @@ func (p *PackageView) PrintTypes(w io.Writer, types []*TypeDoc, level int) {
 			tag = tag_struct
 		}
 		pos := p.fset.Position(d.Decl.Pos())
-		fmt.Fprintf(w, "%d,%s,%s,%s\n", level, tag, d.Type.Name, p.posText(pos))
+		end := p.fset.Position(d.Decl.End())
+		fmt.Fprintf(w, "%d,%s,%s,%s\n", level, tag, d.Type.Name, p.posText(pos, end))
 		p.printFuncsHelper(w, d.Funcs, level+1, tag_type_factor, "")
 		p.printFuncsHelper(w, d.Methods, level+1, tag_type_method, "")
 		p.PrintTypeFields(w, d.Decl, level+1)
@@ -270,10 +291,11 @@ func (p *PackageView) PrintTypeFields(w io.Writer, decl *ast.GenDecl, level int)
 			}
 			for _, m := range list.Names {
 				pos := p.fset.Position(m.Pos())
+				end := p.fset.Position(m.End())
 				if list.Type != nil {
-					fmt.Fprintf(w, "%d,%s,%s,%s@%s\n", level, tag_type_value, m.Name, p.posText(pos), types.ExprString(list.Type))
+					fmt.Fprintf(w, "%d,%s,%s,%s@%s\n", level, tag_type_value, m.Name, p.posText(pos, end), types.ExprString(list.Type))
 				} else {
-					fmt.Fprintf(w, "%d,%s,%s,%s\n", level, tag_type_value, m.Name, p.posText(pos))
+					fmt.Fprintf(w, "%d,%s,%s,%s\n", level, tag_type_value, m.Name, p.posText(pos, end))
 				}
 			}
 		}
@@ -284,7 +306,8 @@ func (p *PackageView) PrintTypeFields(w io.Writer, decl *ast.GenDecl, level int)
 			}
 			for _, m := range list.Names {
 				pos := p.fset.Position(m.Pos())
-				fmt.Fprintf(w, "%d,%s,%s,%s\n", level, tag_type_method, m.Name, p.posText(pos))
+				end := p.fset.Position(m.End())
+				fmt.Fprintf(w, "%d,%s,%s,%s\n", level, tag_type_method, m.Name, p.posText(pos, end))
 			}
 		}
 	}
@@ -299,6 +322,19 @@ func (p *PackageView) PrintImports(w io.Writer, level int, tag, tag_folder strin
 		fmt.Fprintf(w, "%d,%s,%s\n", level, tag_folder, "Imports")
 		level++
 	}
+	var parentPkg *pkgutil.Package
+	if pkgutil.IsVendorExperiment() {
+		for filename, _ := range p.pkg.Files {
+			if !filepath.IsAbs(filename) {
+				name, err := filepath.Abs(filename)
+				if err == nil {
+					filename = name
+				}
+			}
+			parentPkg = pkgutil.ImportFile(filename)
+			break
+		}
+	}
 	for _, name := range p.pdoc.Imports {
 		vname := "\"" + name + "\""
 		var ps []string
@@ -306,10 +342,14 @@ func (p *PackageView) PrintImports(w io.Writer, level int, tag, tag_folder strin
 			for _, v := range file.Imports {
 				if v.Path.Value == vname {
 					pos := p.fset.Position(v.Pos())
-					ps = append(ps, p.posText(pos))
+					end := p.fset.Position(v.End())
+					ps = append(ps, p.posText(pos, end))
 				}
 			}
 		}
+		if parentPkg != nil {
+			name = pkgutil.VendoredImportPath(parentPkg, name)
+		}
 		fmt.Fprintf(w, "%d,%s,%s,%s\n", level, tag, name, strings.Join(ps, ";"))
 	}
 }
@@ -330,6 +370,27 @@ func (p *PackageView) PrintFuncs(w io.Writer, level int, tag_folder string) {
 	p.printFuncsHelper(w, p.pdoc.Funcs, level, tag_func, tag_func_folder)
 }
 
+func (p *PackageView) PrintTodos(w io.Writer, level int, tag, tag_folder string) {
+	hasFolder := false
+	if len(p.pdoc.Todos) > 0 {
+		hasFolder = true
+	}
+	if !hasFolder {
+		return
+	}
+	if len(tag_folder) > 0 {
+		fmt.Fprintf(w, "%d,%s,TodoList\n", level, tag_folder)
+		level++
+	}
+	for _, todo := range p.pdoc.Todos {
+		c := todo.Comments.List[0]
+		pos := p.fset.Position(c.Pos())
+		end := p.fset.Position(c.End())
+		ps := p.posText(pos, end)
+		fmt.Fprintf(w, "%d,%s,%s,%s@%s\n", level, tag, todo.Tag, ps, todo.Text)
+	}
+}
+
 func (p *PackageView) PrintPackage(w io.Writer, level int) {
 	p.PrintHeader(w, level)
 	level++
@@ -338,6 +399,7 @@ func (p *PackageView) PrintPackage(w io.Writer, level int) {
 	p.PrintVars(w, p.pdoc.Consts, level, tag_const, tag_const_folder)
 	p.PrintFuncs(w, level, tag_func_folder)
 	p.PrintTypes(w, p.pdoc.Types, level)
+	p.PrintTodos(w, level, tag_todo, tag_todo_folder)
 }
 
 // level,tag,pos@info

vendor/github.com/visualfc/gotools/finddoc/finddoc.go

@@ -35,6 +35,7 @@ import (
 	"go/parser"
 	"go/printer"
 	"go/token"
+	"go/types"
 	"os"
 	"path"
 	"path/filepath"
@@ -43,8 +44,6 @@ import (
 	"strings"
 
 	"github.com/visualfc/gotools/command"
-	_ "golang.org/x/tools/go/gcimporter"
-	"golang.org/x/tools/go/types"
 )
 
 const usageDoc = `Find documentation for names.

vendor/github.com/visualfc/gotools/goimports/fix.go

@@ -1,394 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package goimports
-
-import (
-	"fmt"
-	"go/ast"
-	"go/build"
-	"go/parser"
-	"go/token"
-	"os"
-	"path"
-	"path/filepath"
-	"strings"
-	"sync"
-
-	"github.com/visualfc/gotools/stdlib"
-
-	"golang.org/x/tools/go/ast/astutil"
-)
-
-// importToGroup is a list of functions which map from an import path to
-// a group number.
-var importToGroup = []func(importPath string) (num int, ok bool){
-	func(importPath string) (num int, ok bool) {
-		if strings.HasPrefix(importPath, "appengine") {
-			return 2, true
-		}
-		return
-	},
-	func(importPath string) (num int, ok bool) {
-		if strings.Contains(importPath, ".") {
-			return 1, true
-		}
-		return
-	},
-}
-
-func importGroup(importPath string) int {
-	for _, fn := range importToGroup {
-		if n, ok := fn(importPath); ok {
-			return n
-		}
-	}
-	return 0
-}
-
-func fixImports(fset *token.FileSet, f *ast.File) (added []string, err error) {
-	// refs are a set of possible package references currently unsatisfied by imports.
-	// first key: either base package (e.g. "fmt") or renamed package
-	// second key: referenced package symbol (e.g. "Println")
-	refs := make(map[string]map[string]bool)
-
-	// decls are the current package imports. key is base package or renamed package.
-	decls := make(map[string]*ast.ImportSpec)
-
-	// collect potential uses of packages.
-	var visitor visitFn
-	visitor = visitFn(func(node ast.Node) ast.Visitor {
-		if node == nil {
-			return visitor
-		}
-		switch v := node.(type) {
-		case *ast.ImportSpec:
-			if v.Name != nil {
-				decls[v.Name.Name] = v
-			} else {
-				local := importPathToName(strings.Trim(v.Path.Value, `\"`))
-				decls[local] = v
-			}
-		case *ast.SelectorExpr:
-			xident, ok := v.X.(*ast.Ident)
-			if !ok {
-				break
-			}
-			if xident.Obj != nil {
-				// if the parser can resolve it, it's not a package ref
-				break
-			}
-			pkgName := xident.Name
-			if refs[pkgName] == nil {
-				refs[pkgName] = make(map[string]bool)
-			}
-			if decls[pkgName] == nil {
-				refs[pkgName][v.Sel.Name] = true
-			}
-		}
-		return visitor
-	})
-	ast.Walk(visitor, f)
-
-	// Search for imports matching potential package references.
-	searches := 0
-	type result struct {
-		ipath string
-		name  string
-		err   error
-	}
-	results := make(chan result)
-	for pkgName, symbols := range refs {
-		if len(symbols) == 0 {
-			continue // skip over packages already imported
-		}
-		go func(pkgName string, symbols map[string]bool) {
-			ipath, rename, err := findImport(pkgName, symbols)
-			r := result{ipath: ipath, err: err}
-			if rename {
-				r.name = pkgName
-			}
-			results <- r
-		}(pkgName, symbols)
-		searches++
-	}
-	for i := 0; i < searches; i++ {
-		result := <-results
-		if result.err != nil {
-			return nil, result.err
-		}
-		if result.ipath != "" {
-			if result.name != "" {
-				astutil.AddNamedImport(fset, f, result.name, result.ipath)
-			} else {
-				astutil.AddImport(fset, f, result.ipath)
-			}
-			added = append(added, result.ipath)
-		}
-	}
-
-	// Nil out any unused ImportSpecs, to be removed in following passes
-	unusedImport := map[string]bool{}
-	for pkg, is := range decls {
-		if refs[pkg] == nil && pkg != "_" && pkg != "." {
-			unusedImport[strings.Trim(is.Path.Value, `"`)] = true
-		}
-	}
-	for ipath := range unusedImport {
-		if ipath == "C" {
-			// Don't remove cgo stuff.
-			continue
-		}
-		astutil.DeleteImport(fset, f, ipath)
-	}
-
-	return added, nil
-}
-
-// importPathToName returns the package name for the given import path.
-var importPathToName = importPathToNameGoPath
-
-// importPathToNameBasic assumes the package name is the base of import path.
-func importPathToNameBasic(importPath string) (packageName string) {
-	return path.Base(importPath)
-}
-
-// importPathToNameGoPath finds out the actual package name, as declared in its .go files.
-// If there's a problem, it falls back to using importPathToNameBasic.
-func importPathToNameGoPath(importPath string) (packageName string) {
-	if stdlib.IsStdPkg(importPath) {
-		return path.Base(importPath)
-	}
-	if buildPkg, err := build.Import(importPath, "", 0); err == nil {
-		return buildPkg.Name
-	} else {
-		return importPathToNameBasic(importPath)
-	}
-}
-
-type pkg struct {
-	importpath string // full pkg import path, e.g. "net/http"
-	dir        string // absolute file path to pkg directory e.g. "/usr/lib/go/src/fmt"
-}
-
-var pkgIndexOnce sync.Once
-
-var pkgIndex struct {
-	sync.Mutex
-	m map[string][]pkg // shortname => []pkg, e.g "http" => "net/http"
-}
-
-// gate is a semaphore for limiting concurrency.
-type gate chan struct{}
-
-func (g gate) enter() { g <- struct{}{} }
-func (g gate) leave() { <-g }
-
-// fsgate protects the OS & filesystem from too much concurrency.
-// Too much disk I/O -> too many threads -> swapping and bad scheduling.
-var fsgate = make(gate, 8)
-
-func loadPkgIndex() {
-	pkgIndex.Lock()
-	pkgIndex.m = make(map[string][]pkg)
-	pkgIndex.Unlock()
-
-	var wg sync.WaitGroup
-	for _, path := range build.Default.SrcDirs() {
-		fsgate.enter()
-		f, err := os.Open(path)
-		if err != nil {
-			fsgate.leave()
-			fmt.Fprint(os.Stderr, err)
-			continue
-		}
-		children, err := f.Readdir(-1)
-		f.Close()
-		fsgate.leave()
-		if err != nil {
-			fmt.Fprint(os.Stderr, err)
-			continue
-		}
-		for _, child := range children {
-			if child.IsDir() {
-				wg.Add(1)
-				go func(path, name string) {
-					defer wg.Done()
-					loadPkg(&wg, path, name)
-				}(path, child.Name())
-			}
-		}
-	}
-	wg.Wait()
-}
-
-func loadPkg(wg *sync.WaitGroup, root, pkgrelpath string) {
-	importpath := filepath.ToSlash(pkgrelpath)
-	dir := filepath.Join(root, importpath)
-
-	fsgate.enter()
-	defer fsgate.leave()
-	pkgDir, err := os.Open(dir)
-	if err != nil {
-		return
-	}
-	children, err := pkgDir.Readdir(-1)
-	pkgDir.Close()
-	if err != nil {
-		return
-	}
-	// hasGo tracks whether a directory actually appears to be a
-	// Go source code directory. If $GOPATH == $HOME, and
-	// $HOME/src has lots of other large non-Go projects in it,
-	// then the calls to importPathToName below can be expensive.
-	hasGo := false
-	for _, child := range children {
-		name := child.Name()
-		if name == "" {
-			continue
-		}
-		if c := name[0]; c == '.' || ('0' <= c && c <= '9') {
-			continue
-		}
-		if strings.HasSuffix(name, ".go") {
-			hasGo = true
-		}
-		if child.IsDir() {
-			wg.Add(1)
-			go func(root, name string) {
-				defer wg.Done()
-				loadPkg(wg, root, name)
-			}(root, filepath.Join(importpath, name))
-		}
-	}
-	if hasGo {
-		shortName := importPathToName(importpath)
-		pkgIndex.Lock()
-		pkgIndex.m[shortName] = append(pkgIndex.m[shortName], pkg{
-			importpath: importpath,
-			dir:        dir,
-		})
-		pkgIndex.Unlock()
-	}
-
-}
-
-// loadExports returns a list exports for a package.
-var loadExports = loadExportsGoPath
-
-func loadExportsGoPath(dir string) map[string]bool {
-	exports := make(map[string]bool)
-	buildPkg, err := build.ImportDir(dir, 0)
-	if err != nil {
-		if strings.Contains(err.Error(), "no buildable Go source files in") {
-			return nil
-		}
-		fmt.Fprintf(os.Stderr, "could not import %q: %v\n", dir, err)
-		return nil
-	}
-	fset := token.NewFileSet()
-	for _, files := range [...][]string{buildPkg.GoFiles, buildPkg.CgoFiles} {
-		for _, file := range files {
-			f, err := parser.ParseFile(fset, filepath.Join(dir, file), nil, 0)
-			if err != nil {
-				fmt.Fprintf(os.Stderr, "could not parse %q: %v\n", file, err)
-				continue
-			}
-			for name := range f.Scope.Objects {
-				if ast.IsExported(name) {
-					exports[name] = true
-				}
-			}
-		}
-	}
-	return exports
-}
-
-// findImport searches for a package with the given symbols.
-// If no package is found, findImport returns "".
-// Declared as a variable rather than a function so goimports can be easily
-// extended by adding a file with an init function.
-var findImport = findImportGoPath
-
-func findImportGoPath(pkgName string, symbols map[string]bool) (string, bool, error) {
-	// Fast path for the standard library.
-	// In the common case we hopefully never have to scan the GOPATH, which can
-	// be slow with moving disks.
-	if pkg, rename, ok := findImportStdlib(pkgName, symbols); ok {
-		return pkg, rename, nil
-	}
-
-	// TODO(sameer): look at the import lines for other Go files in the
-	// local directory, since the user is likely to import the same packages
-	// in the current Go file.  Return rename=true when the other Go files
-	// use a renamed package that's also used in the current file.
-
-	pkgIndexOnce.Do(loadPkgIndex)
-
-	// Collect exports for packages with matching names.
-	var wg sync.WaitGroup
-	var pkgsMu sync.Mutex // guards pkgs
-	// full importpath => exported symbol => True
-	// e.g. "net/http" => "Client" => True
-	pkgs := make(map[string]map[string]bool)
-	pkgIndex.Lock()
-	for _, pkg := range pkgIndex.m[pkgName] {
-		wg.Add(1)
-		go func(importpath, dir string) {
-			defer wg.Done()
-			exports := loadExports(dir)
-			if exports != nil {
-				pkgsMu.Lock()
-				pkgs[importpath] = exports
-				pkgsMu.Unlock()
-			}
-		}(pkg.importpath, pkg.dir)
-	}
-	pkgIndex.Unlock()
-	wg.Wait()
-
-	// Filter out packages missing required exported symbols.
-	for symbol := range symbols {
-		for importpath, exports := range pkgs {
-			if !exports[symbol] {
-				delete(pkgs, importpath)
-			}
-		}
-	}
-	if len(pkgs) == 0 {
-		return "", false, nil
-	}
-
-	// If there are multiple candidate packages, the shortest one wins.
-	// This is a heuristic to prefer the standard library (e.g. "bytes")
-	// over e.g. "github.com/foo/bar/bytes".
-	shortest := ""
-	for importPath := range pkgs {
-		if shortest == "" || len(importPath) < len(shortest) {
-			shortest = importPath
-		}
-	}
-	return shortest, false, nil
-}
-
-type visitFn func(node ast.Node) ast.Visitor
-
-func (fn visitFn) Visit(node ast.Node) ast.Visitor {
-	return fn(node)
-}
-
-func findImportStdlib(shortPkg string, symbols map[string]bool) (importPath string, rename, ok bool) {
-	for symbol := range symbols {
-		path := stdlib.Symbols[shortPkg+"."+symbol]
-		if path == "" {
-			return "", false, false
-		}
-		if importPath != "" && importPath != path {
-			// Ambiguous. Symbols pointed to different things.
-			return "", false, false
-		}
-		importPath = path
-	}
-	return importPath, false, importPath != ""
-}

vendor/github.com/visualfc/gotools/goimports/goimports.go

@@ -1,206 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package goimports
-
-import (
-	"bytes"
-	"fmt"
-	"go/parser"
-	"go/printer"
-	"go/scanner"
-	"go/token"
-	"io"
-	"io/ioutil"
-	"os"
-	"os/exec"
-	"path/filepath"
-	"runtime"
-	"strings"
-	"sync"
-
-	"github.com/visualfc/gotools/command"
-)
-
-var Command = &command.Command{
-	Run:       runGoimports,
-	UsageLine: "goimports [flags] [path ...]",
-	Short:     "updates go import lines",
-	Long:      `goimports updates your Go import lines, adding missing ones and removing unreferenced ones. `,
-}
-
-var (
-	goimportsList      bool
-	goimportsWrite     bool
-	goimportsDiff      bool
-	goimportsAllErrors bool
-
-	// layout control
-	goimportsComments  bool
-	goimportsTabWidth  int
-	goimportsTabIndent bool
-)
-
-//func init
-func init() {
-	Command.Flag.BoolVar(&goimportsList, "l", false, "list files whose formatting differs from goimport's")
-	Command.Flag.BoolVar(&goimportsWrite, "w", false, "write result to (source) file instead of stdout")
-	Command.Flag.BoolVar(&goimportsDiff, "d", false, "display diffs instead of rewriting files")
-	Command.Flag.BoolVar(&goimportsAllErrors, "e", false, "report all errors (not just the first 10 on different lines)")
-
-	// layout control
-	Command.Flag.BoolVar(&goimportsComments, "comments", true, "print comments")
-	Command.Flag.IntVar(&goimportsTabWidth, "tabwidth", 8, "tab width")
-	Command.Flag.BoolVar(&goimportsTabIndent, "tabs", true, "indent with tabs")
-}
-
-var (
-	fileSet  = token.NewFileSet() // per process FileSet
-	exitCode = 0
-
-	initModesOnce sync.Once // guards calling initModes
-	parserMode    parser.Mode
-	printerMode   printer.Mode
-	options       *Options
-)
-
-func report(err error) {
-	scanner.PrintError(os.Stderr, err)
-	exitCode = 2
-}
-
-func runGoimports(cmd *command.Command, args []string) error {
-	runtime.GOMAXPROCS(runtime.NumCPU())
-
-	if goimportsTabWidth < 0 {
-		fmt.Fprintf(os.Stderr, "negative tabwidth %d\n", goimportsTabWidth)
-		exitCode = 2
-		os.Exit(exitCode)
-		return os.ErrInvalid
-	}
-
-	options = &Options{
-		TabWidth:  goimportsTabWidth,
-		TabIndent: goimportsTabIndent,
-		Comments:  goimportsComments,
-		AllErrors: goimportsAllErrors,
-		Fragment:  true,
-	}
-
-	if len(args) == 0 {
-		if err := processFile("<standard input>", os.Stdin, os.Stdout, true); err != nil {
-			report(err)
-		}
-	} else {
-		for _, path := range args {
-			switch dir, err := os.Stat(path); {
-			case err != nil:
-				report(err)
-			case dir.IsDir():
-				walkDir(path)
-			default:
-				if err := processFile(path, nil, os.Stdout, false); err != nil {
-					report(err)
-				}
-			}
-		}
-	}
-	os.Exit(exitCode)
-	return nil
-}
-
-func isGoFile(f os.FileInfo) bool {
-	// ignore non-Go files
-	name := f.Name()
-	return !f.IsDir() && !strings.HasPrefix(name, ".") && strings.HasSuffix(name, ".go")
-}
-
-func processFile(filename string, in io.Reader, out io.Writer, stdin bool) error {
-	if in == nil {
-		f, err := os.Open(filename)
-		if err != nil {
-			return err
-		}
-		defer f.Close()
-		in = f
-	}
-
-	src, err := ioutil.ReadAll(in)
-	if err != nil {
-		return err
-	}
-
-	res, err := Process(filename, src, options)
-	if err != nil {
-		return err
-	}
-
-	if !bytes.Equal(src, res) {
-		// formatting has changed
-		if goimportsList {
-			fmt.Fprintln(out, filename)
-		}
-		if goimportsWrite {
-			err = ioutil.WriteFile(filename, res, 0)
-			if err != nil {
-				return err
-			}
-		}
-		if goimportsDiff {
-			data, err := diff(src, res)
-			if err != nil {
-				return fmt.Errorf("computing diff: %s", err)
-			}
-			fmt.Printf("diff %s gofmt/%s\n", filename, filename)
-			out.Write(data)
-		}
-	}
-
-	if !goimportsList && !goimportsWrite && !goimportsDiff {
-		_, err = out.Write(res)
-	}
-
-	return err
-}
-
-func visitFile(path string, f os.FileInfo, err error) error {
-	if err == nil && isGoFile(f) {
-		err = processFile(path, nil, os.Stdout, false)
-	}
-	if err != nil {
-		report(err)
-	}
-	return nil
-}
-
-func walkDir(path string) {
-	filepath.Walk(path, visitFile)
-}
-
-func diff(b1, b2 []byte) (data []byte, err error) {
-	f1, err := ioutil.TempFile("", "gofmt")
-	if err != nil {
-		return
-	}
-	defer os.Remove(f1.Name())
-	defer f1.Close()
-
-	f2, err := ioutil.TempFile("", "gofmt")
-	if err != nil {
-		return
-	}
-	defer os.Remove(f2.Name())
-	defer f2.Close()
-
-	f1.Write(b1)
-	f2.Write(b2)
-
-	data, err = exec.Command("diff", "-u", f1.Name(), f2.Name()).CombinedOutput()
-	if len(data) > 0 {
-		// diff exits with a non-zero status when the files don't match.
-		// Ignore that failure as long as we get output.
-		err = nil
-	}
-	return
-}

vendor/github.com/visualfc/gotools/goimports/imports.go

@@ -1,281 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package imports implements a Go pretty-printer (like package "go/format")
-// that also adds or removes import statements as necessary.
-package goimports
-
-import (
-	"bufio"
-	"bytes"
-	"fmt"
-	"go/ast"
-	"go/format"
-	"go/parser"
-	"go/printer"
-	"go/token"
-	"io"
-	"regexp"
-	"strconv"
-	"strings"
-
-	"golang.org/x/tools/go/ast/astutil"
-)
-
-// Options specifies options for processing files.
-type Options struct {
-	Fragment  bool // Accept fragment of a source file (no package statement)
-	AllErrors bool // Report all errors (not just the first 10 on different lines)
-
-	Comments  bool // Print comments (true if nil *Options provided)
-	TabIndent bool // Use tabs for indent (true if nil *Options provided)
-	Format    bool
-	TabWidth  int // Tab width (8 if nil *Options provided)
-}
-
-// Process formats and adjusts imports for the provided file.
-// If opt is nil the defaults are used.
-func Process(filename string, src []byte, opt *Options) ([]byte, error) {
-	if opt == nil {
-		opt = &Options{Comments: true, TabIndent: true, TabWidth: 8}
-	}
-
-	fileSet := token.NewFileSet()
-	file, adjust, err := goImportParse(fileSet, filename, src, opt)
-	if err != nil {
-		return nil, err
-	}
-
-	_, err = fixImports(fileSet, file)
-	if err != nil {
-		return nil, err
-	}
-
-	sortImports(fileSet, file)
-	imps := astutil.Imports(fileSet, file)
-
-	var spacesBefore []string // import paths we need spaces before
-	for _, impSection := range imps {
-		// Within each block of contiguous imports, see if any
-		// import lines are in different group numbers. If so,
-		// we'll need to put a space between them so it's
-		// compatible with gofmt.
-		lastGroup := -1
-		for _, importSpec := range impSection {
-			importPath, _ := strconv.Unquote(importSpec.Path.Value)
-			groupNum := importGroup(importPath)
-			if groupNum != lastGroup && lastGroup != -1 {
-				spacesBefore = append(spacesBefore, importPath)
-			}
-			lastGroup = groupNum
-		}
-
-	}
-
-	printerMode := printer.UseSpaces
-	if opt.TabIndent {
-		printerMode |= printer.TabIndent
-	}
-	printConfig := &printer.Config{Mode: printerMode, Tabwidth: opt.TabWidth}
-
-	var buf bytes.Buffer
-	err = printConfig.Fprint(&buf, fileSet, file)
-	if err != nil {
-		return nil, err
-	}
-	out := buf.Bytes()
-	if adjust != nil {
-		out = adjust(src, out)
-	}
-	if len(spacesBefore) > 0 {
-		out = addImportSpaces(bytes.NewReader(out), spacesBefore)
-	}
-	if opt.Format {
-		out, err = format.Source(out)
-		if err != nil {
-			return nil, err
-		}
-	}
-	return out, nil
-}
-
-// parse parses src, which was read from filename,
-// as a Go source file or statement list.
-func goImportParse(fset *token.FileSet, filename string, src []byte, opt *Options) (*ast.File, func(orig, src []byte) []byte, error) {
-	parserMode := parser.Mode(0)
-	if opt.Comments {
-		parserMode |= parser.ParseComments
-	}
-	if opt.AllErrors {
-		parserMode |= parser.AllErrors
-	}
-
-	// Try as whole source file.
-	file, err := parser.ParseFile(fset, filename, src, parserMode)
-	if err == nil {
-		return file, nil, nil
-	}
-	// If the error is that the source file didn't begin with a
-	// package line and we accept fragmented input, fall through to
-	// try as a source fragment.  Stop and return on any other error.
-	if !opt.Fragment || !strings.Contains(err.Error(), "expected 'package'") {
-		return nil, nil, err
-	}
-
-	// If this is a declaration list, make it a source file
-	// by inserting a package clause.
-	// Insert using a ;, not a newline, so that the line numbers
-	// in psrc match the ones in src.
-	psrc := append([]byte("package main;"), src...)
-	file, err = parser.ParseFile(fset, filename, psrc, parserMode)
-	if err == nil {
-		// If a main function exists, we will assume this is a main
-		// package and leave the file.
-		if containsMainFunc(file) {
-			return file, nil, nil
-		}
-
-		adjust := func(orig, src []byte) []byte {
-			// Remove the package clause.
-			// Gofmt has turned the ; into a \n.
-			src = src[len("package main\n"):]
-			return matchSpace(orig, src)
-		}
-		return file, adjust, nil
-	}
-	// If the error is that the source file didn't begin with a
-	// declaration, fall through to try as a statement list.
-	// Stop and return on any other error.
-	if !strings.Contains(err.Error(), "expected declaration") {
-		return nil, nil, err
-	}
-
-	// If this is a statement list, make it a source file
-	// by inserting a package clause and turning the list
-	// into a function body.  This handles expressions too.
-	// Insert using a ;, not a newline, so that the line numbers
-	// in fsrc match the ones in src.
-	fsrc := append(append([]byte("package p; func _() {"), src...), '}')
-	file, err = parser.ParseFile(fset, filename, fsrc, parserMode)
-	if err == nil {
-		adjust := func(orig, src []byte) []byte {
-			// Remove the wrapping.
-			// Gofmt has turned the ; into a \n\n.
-			src = src[len("package p\n\nfunc _() {"):]
-			src = src[:len(src)-len("}\n")]
-			// Gofmt has also indented the function body one level.
-			// Remove that indent.
-			src = bytes.Replace(src, []byte("\n\t"), []byte("\n"), -1)
-			return matchSpace(orig, src)
-		}
-		return file, adjust, nil
-	}
-
-	// Failed, and out of options.
-	return nil, nil, err
-}
-
-// containsMainFunc checks if a file contains a function declaration with the
-// function signature 'func main()'
-func containsMainFunc(file *ast.File) bool {
-	for _, decl := range file.Decls {
-		if f, ok := decl.(*ast.FuncDecl); ok {
-			if f.Name.Name != "main" {
-				continue
-			}
-
-			if len(f.Type.Params.List) != 0 {
-				continue
-			}
-
-			if f.Type.Results != nil && len(f.Type.Results.List) != 0 {
-				continue
-			}
-
-			return true
-		}
-	}
-
-	return false
-}
-
-func cutSpace(b []byte) (before, middle, after []byte) {
-	i := 0
-	for i < len(b) && (b[i] == ' ' || b[i] == '\t' || b[i] == '\n') {
-		i++
-	}
-	j := len(b)
-	for j > 0 && (b[j-1] == ' ' || b[j-1] == '\t' || b[j-1] == '\n') {
-		j--
-	}
-	if i <= j {
-		return b[:i], b[i:j], b[j:]
-	}
-	return nil, nil, b[j:]
-}
-
-// matchSpace reformats src to use the same space context as orig.
-// 1) If orig begins with blank lines, matchSpace inserts them at the beginning of src.
-// 2) matchSpace copies the indentation of the first non-blank line in orig
-//    to every non-blank line in src.
-// 3) matchSpace copies the trailing space from orig and uses it in place
-//   of src's trailing space.
-func matchSpace(orig []byte, src []byte) []byte {
-	before, _, after := cutSpace(orig)
-	i := bytes.LastIndex(before, []byte{'\n'})
-	before, indent := before[:i+1], before[i+1:]
-
-	_, src, _ = cutSpace(src)
-
-	var b bytes.Buffer
-	b.Write(before)
-	for len(src) > 0 {
-		line := src
-		if i := bytes.IndexByte(line, '\n'); i >= 0 {
-			line, src = line[:i+1], line[i+1:]
-		} else {
-			src = nil
-		}
-		if len(line) > 0 && line[0] != '\n' { // not blank
-			b.Write(indent)
-		}
-		b.Write(line)
-	}
-	b.Write(after)
-	return b.Bytes()
-}
-
-var impLine = regexp.MustCompile(`^\s+(?:[\w\.]+\s+)?"(.+)"`)
-
-func addImportSpaces(r io.Reader, breaks []string) []byte {
-	var out bytes.Buffer
-	sc := bufio.NewScanner(r)
-	inImports := false
-	done := false
-	for sc.Scan() {
-		s := sc.Text()
-
-		if !inImports && !done && strings.HasPrefix(s, "import") {
-			inImports = true
-		}
-		if inImports && (strings.HasPrefix(s, "var") ||
-			strings.HasPrefix(s, "func") ||
-			strings.HasPrefix(s, "const") ||
-			strings.HasPrefix(s, "type")) {
-			done = true
-			inImports = false
-		}
-		if inImports && len(breaks) > 0 {
-			if m := impLine.FindStringSubmatch(s); m != nil {
-				if m[1] == string(breaks[0]) {
-					out.WriteByte('\n')
-					breaks = breaks[1:]
-				}
-			}
-		}
-
-		fmt.Fprintln(&out, s)
-	}
-	return out.Bytes()
-}

vendor/github.com/visualfc/gotools/goimports/sortimports.go

@@ -1,214 +0,0 @@
-// +build go1.2
-
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Hacked up copy of go/ast/import.go
-
-package goimports
-
-import (
-	"go/ast"
-	"go/token"
-	"sort"
-	"strconv"
-)
-
-// sortImports sorts runs of consecutive import lines in import blocks in f.
-// It also removes duplicate imports when it is possible to do so without data loss.
-func sortImports(fset *token.FileSet, f *ast.File) {
-	for i, d := range f.Decls {
-		d, ok := d.(*ast.GenDecl)
-		if !ok || d.Tok != token.IMPORT {
-			// Not an import declaration, so we're done.
-			// Imports are always first.
-			break
-		}
-
-		if len(d.Specs) == 0 {
-			// Empty import block, remove it.
-			f.Decls = append(f.Decls[:i], f.Decls[i+1:]...)
-		}
-
-		if !d.Lparen.IsValid() {
-			// Not a block: sorted by default.
-			continue
-		}
-
-		// Identify and sort runs of specs on successive lines.
-		i := 0
-		specs := d.Specs[:0]
-		for j, s := range d.Specs {
-			if j > i && fset.Position(s.Pos()).Line > 1+fset.Position(d.Specs[j-1].End()).Line {
-				// j begins a new run.  End this one.
-				specs = append(specs, sortSpecs(fset, f, d.Specs[i:j])...)
-				i = j
-			}
-		}
-		specs = append(specs, sortSpecs(fset, f, d.Specs[i:])...)
-		d.Specs = specs
-
-		// Deduping can leave a blank line before the rparen; clean that up.
-		if len(d.Specs) > 0 {
-			lastSpec := d.Specs[len(d.Specs)-1]
-			lastLine := fset.Position(lastSpec.Pos()).Line
-			if rParenLine := fset.Position(d.Rparen).Line; rParenLine > lastLine+1 {
-				fset.File(d.Rparen).MergeLine(rParenLine - 1)
-			}
-		}
-	}
-}
-
-func importPath(s ast.Spec) string {
-	t, err := strconv.Unquote(s.(*ast.ImportSpec).Path.Value)
-	if err == nil {
-		return t
-	}
-	return ""
-}
-
-func importName(s ast.Spec) string {
-	n := s.(*ast.ImportSpec).Name
-	if n == nil {
-		return ""
-	}
-	return n.Name
-}
-
-func importComment(s ast.Spec) string {
-	c := s.(*ast.ImportSpec).Comment
-	if c == nil {
-		return ""
-	}
-	return c.Text()
-}
-
-// collapse indicates whether prev may be removed, leaving only next.
-func collapse(prev, next ast.Spec) bool {
-	if importPath(next) != importPath(prev) || importName(next) != importName(prev) {
-		return false
-	}
-	return prev.(*ast.ImportSpec).Comment == nil
-}
-
-type posSpan struct {
-	Start token.Pos
-	End   token.Pos
-}
-
-func sortSpecs(fset *token.FileSet, f *ast.File, specs []ast.Spec) []ast.Spec {
-	// Can't short-circuit here even if specs are already sorted,
-	// since they might yet need deduplication.
-	// A lone import, however, may be safely ignored.
-	if len(specs) <= 1 {
-		return specs
-	}
-
-	// Record positions for specs.
-	pos := make([]posSpan, len(specs))
-	for i, s := range specs {
-		pos[i] = posSpan{s.Pos(), s.End()}
-	}
-
-	// Identify comments in this range.
-	// Any comment from pos[0].Start to the final line counts.
-	lastLine := fset.Position(pos[len(pos)-1].End).Line
-	cstart := len(f.Comments)
-	cend := len(f.Comments)
-	for i, g := range f.Comments {
-		if g.Pos() < pos[0].Start {
-			continue
-		}
-		if i < cstart {
-			cstart = i
-		}
-		if fset.Position(g.End()).Line > lastLine {
-			cend = i
-			break
-		}
-	}
-	comments := f.Comments[cstart:cend]
-
-	// Assign each comment to the import spec preceding it.
-	importComment := map[*ast.ImportSpec][]*ast.CommentGroup{}
-	specIndex := 0
-	for _, g := range comments {
-		for specIndex+1 < len(specs) && pos[specIndex+1].Start <= g.Pos() {
-			specIndex++
-		}
-		s := specs[specIndex].(*ast.ImportSpec)
-		importComment[s] = append(importComment[s], g)
-	}
-
-	// Sort the import specs by import path.
-	// Remove duplicates, when possible without data loss.
-	// Reassign the import paths to have the same position sequence.
-	// Reassign each comment to abut the end of its spec.
-	// Sort the comments by new position.
-	sort.Sort(byImportSpec(specs))
-
-	// Dedup. Thanks to our sorting, we can just consider
-	// adjacent pairs of imports.
-	deduped := specs[:0]
-	for i, s := range specs {
-		if i == len(specs)-1 || !collapse(s, specs[i+1]) {
-			deduped = append(deduped, s)
-		} else {
-			p := s.Pos()
-			fset.File(p).MergeLine(fset.Position(p).Line)
-		}
-	}
-	specs = deduped
-
-	// Fix up comment positions
-	for i, s := range specs {
-		s := s.(*ast.ImportSpec)
-		if s.Name != nil {
-			s.Name.NamePos = pos[i].Start
-		}
-		s.Path.ValuePos = pos[i].Start
-		s.EndPos = pos[i].End
-		for _, g := range importComment[s] {
-			for _, c := range g.List {
-				c.Slash = pos[i].End
-			}
-		}
-	}
-
-	sort.Sort(byCommentPos(comments))
-
-	return specs
-}
-
-type byImportSpec []ast.Spec // slice of *ast.ImportSpec
-
-func (x byImportSpec) Len() int      { return len(x) }
-func (x byImportSpec) Swap(i, j int) { x[i], x[j] = x[j], x[i] }
-func (x byImportSpec) Less(i, j int) bool {
-	ipath := importPath(x[i])
-	jpath := importPath(x[j])
-
-	igroup := importGroup(ipath)
-	jgroup := importGroup(jpath)
-	if igroup != jgroup {
-		return igroup < jgroup
-	}
-
-	if ipath != jpath {
-		return ipath < jpath
-	}
-	iname := importName(x[i])
-	jname := importName(x[j])
-
-	if iname != jname {
-		return iname < jname
-	}
-	return importComment(x[i]) < importComment(x[j])
-}
-
-type byCommentPos []*ast.CommentGroup
-
-func (x byCommentPos) Len() int           { return len(x) }
-func (x byCommentPos) Swap(i, j int)      { x[i], x[j] = x[j], x[i] }
-func (x byCommentPos) Less(i, j int) bool { return x[i].Pos() < x[j].Pos() }

vendor/github.com/visualfc/gotools/goimports/sortimports_compat.go

@@ -1,14 +0,0 @@
-// +build !go1.2
-
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package goimports
-
-import "go/ast"
-
-// Go 1.1 users don't get fancy package grouping.
-// But this is still gofmt-compliant:
-
-var sortImports = ast.SortImports

vendor/github.com/visualfc/gotools/oracle/oracle.go

@@ -7,13 +7,11 @@ package oracle
 import (
 	"fmt"
 	"go/build"
-	"log"
 	"os"
 	"runtime"
 
 	"github.com/visualfc/gotools/command"
-
+	"github.com/visualfc/gotools/oracle/oracle"
-	"golang.org/x/tools/oracle"
 )
 
 //The mode argument determines the query to perform:
@@ -60,21 +58,21 @@ func runOracle(cmd *command.Command, args []string) error {
 	}
 	mode := args[0]
 	args = args[1:]
-	if args[0] == "." {
+	//	if args[0] == "." {
-		pkgPath, err := os.Getwd()
+	//		pkgPath, err := os.Getwd()
-		if err != nil {
+	//		if err != nil {
-			log.Fatalln(err)
+	//			log.Fatalln(err)
-		}
+	//		}
-		pkg, err := build.Default.ImportDir(pkgPath, 0)
+	//		pkg, err := build.Default.ImportDir(pkgPath, 0)
-		if err != nil {
+	//		if err != nil {
-			log.Fatalln(err)
+	//			log.Fatalln(err)
-		}
+	//		}
-		args = pkg.GoFiles
+	//		args = pkg.GoFiles
-		//log.Println(pkg.ImportPath)
+	//		//log.Println(pkg.ImportPath)
-		if pkg.ImportPath != "." && pkg.ImportPath != "" {
+	//		if pkg.ImportPath != "." && pkg.ImportPath != "" {
-			args = []string{pkg.ImportPath}
+	//			args = []string{pkg.ImportPath}
-		}
+	//		}
-	}
+	//	}
 	query := oracle.Query{
 		Mode:       mode,
 		Pos:        oraclePos,

vendor/github.com/visualfc/gotools/oracle/oracle/TODO

@@ -0,0 +1,83 @@
+
+
+ORACLE TODO
+===========
+
+General
+=======
+
+Save unsaved editor buffers into an archive and provide that to the
+tools, which should act as if they were saved.
+
+Include complete pos/end information Serial output.
+  But beware that sometimes a single token (e.g. +) is more helpful
+  than the pos/end of the containing expression (e.g. x \n + \n y).
+
+Specific queries
+================
+
+callers, callees
+
+  Use a type-based (e.g. RTA) callgraph when a callers/callees query is
+  outside the analysis scope.
+
+implements
+
+   Make it require that the selection is a type, and show only the
+   implements relation as it applies to that type.
+
+definition, referrers
+
+  definition: Make it work with qualified identifiers (SelectorExpr) too.
+
+  references: Make it work on things that are implicit idents, like
+  import specs, perhaps?
+
+what
+
+  Report def/ref info if available.
+  Editors could use it to highlight all idents of the same local var.
+
+  More tests.
+
+pointsto
+
+  When invoked on a function Ident, we get an error.
+
+  When invoked on a named return parameter, we get an error.
+
+describe
+
+  When invoked on a var, we want to see the type and its methods.
+
+  Split "show type" and "describe syntax" into separate commands?
+
+peers
+
+  Permit querying from a makechan, for...range, or reflective op.
+
+  Report aliasing reflect.{Send,Recv,Close} and close() operations.
+
+New queries
+
+"updaters": show all statements that may update the selected lvalue
+  (local, global, field, etc).
+
+"creators": show all places where an object of type T is created
+  (&T{}, var t T, new(T), new(struct{array [3]T}), etc.
+  (Useful for datatypes whose zero value is not safe)
+
+
+Editor-specific
+===============
+
+Add support for "what" to .el; clean up.
+
+Emacs: use JSON to get the raw information from the oracle.  Don't
+ open an editor buffer for simpler queries, just jump to the result
+ and/or display it in the modeline.
+
+Emacs: go-root-and-paths depends on the current buffer, so be sure to
+   call it from within the source file, not the *go-oracle* buffer:
+   the user may have switched workspaces and the oracle should run in
+   the new one.

vendor/github.com/visualfc/gotools/oracle/oracle/callees.go

@@ -0,0 +1,260 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build go1.5
+
+package oracle
+
+import (
+	"fmt"
+	"go/ast"
+	"go/token"
+	"go/types"
+	"sort"
+
+	"github.com/visualfc/gotools/oracle/oracle/serial"
+	"golang.org/x/tools/go/loader"
+	"golang.org/x/tools/go/pointer"
+	"golang.org/x/tools/go/ssa"
+	"golang.org/x/tools/go/ssa/ssautil"
+)
+
+// Callees reports the possible callees of the function call site
+// identified by the specified source location.
+func callees(q *Query) error {
+	lconf := loader.Config{Build: q.Build}
+
+	if err := setPTAScope(&lconf, q.Scope); err != nil {
+		return err
+	}
+
+	// Load/parse/type-check the program.
+	lprog, err := lconf.Load()
+	if err != nil {
+		return err
+	}
+	q.Fset = lprog.Fset
+
+	qpos, err := parseQueryPos(lprog, q.Pos, true) // needs exact pos
+	if err != nil {
+		return err
+	}
+
+	// Determine the enclosing call for the specified position.
+	var e *ast.CallExpr
+	for _, n := range qpos.path {
+		if e, _ = n.(*ast.CallExpr); e != nil {
+			break
+		}
+	}
+	if e == nil {
+		return fmt.Errorf("there is no function call here")
+	}
+	// TODO(adonovan): issue an error if the call is "too far
+	// away" from the current selection, as this most likely is
+	// not what the user intended.
+
+	// Reject type conversions.
+	if qpos.info.Types[e.Fun].IsType() {
+		return fmt.Errorf("this is a type conversion, not a function call")
+	}
+
+	// Deal with obviously static calls before constructing SSA form.
+	// Some static calls may yet require SSA construction,
+	// e.g.  f := func(){}; f().
+	switch funexpr := unparen(e.Fun).(type) {
+	case *ast.Ident:
+		switch obj := qpos.info.Uses[funexpr].(type) {
+		case *types.Builtin:
+			// Reject calls to built-ins.
+			return fmt.Errorf("this is a call to the built-in '%s' operator", obj.Name())
+		case *types.Func:
+			// This is a static function call
+			q.result = &calleesTypesResult{
+				site:   e,
+				callee: obj,
+			}
+			return nil
+		}
+	case *ast.SelectorExpr:
+		sel := qpos.info.Selections[funexpr]
+		if sel == nil {
+			// qualified identifier.
+			// May refer to top level function variable
+			// or to top level function.
+			callee := qpos.info.Uses[funexpr.Sel]
+			if obj, ok := callee.(*types.Func); ok {
+				q.result = &calleesTypesResult{
+					site:   e,
+					callee: obj,
+				}
+				return nil
+			}
+		} else if sel.Kind() == types.MethodVal {
+			// Inspect the receiver type of the selected method.
+			// If it is concrete, the call is statically dispatched.
+			// (Due to implicit field selections, it is not enough to look
+			// at sel.Recv(), the type of the actual receiver expression.)
+			method := sel.Obj().(*types.Func)
+			recvtype := method.Type().(*types.Signature).Recv().Type()
+			if !types.IsInterface(recvtype) {
+				// static method call
+				q.result = &calleesTypesResult{
+					site:   e,
+					callee: method,
+				}
+				return nil
+			}
+		}
+	}
+
+	prog := ssautil.CreateProgram(lprog, ssa.GlobalDebug)
+
+	ptaConfig, err := setupPTA(prog, lprog, q.PTALog, q.Reflection)
+	if err != nil {
+		return err
+	}
+
+	pkg := prog.Package(qpos.info.Pkg)
+	if pkg == nil {
+		return fmt.Errorf("no SSA package")
+	}
+
+	// Defer SSA construction till after errors are reported.
+	prog.Build()
+
+	// Ascertain calling function and call site.
+	callerFn := ssa.EnclosingFunction(pkg, qpos.path)
+	if callerFn == nil {
+		return fmt.Errorf("no SSA function built for this location (dead code?)")
+	}
+
+	// Find the call site.
+	site, err := findCallSite(callerFn, e)
+	if err != nil {
+		return err
+	}
+
+	funcs, err := findCallees(ptaConfig, site)
+	if err != nil {
+		return err
+	}
+
+	q.result = &calleesSSAResult{
+		site:  site,
+		funcs: funcs,
+	}
+	return nil
+}
+
+func findCallSite(fn *ssa.Function, call *ast.CallExpr) (ssa.CallInstruction, error) {
+	instr, _ := fn.ValueForExpr(call)
+	callInstr, _ := instr.(ssa.CallInstruction)
+	if instr == nil {
+		return nil, fmt.Errorf("this call site is unreachable in this analysis")
+	}
+	return callInstr, nil
+}
+
+func findCallees(conf *pointer.Config, site ssa.CallInstruction) ([]*ssa.Function, error) {
+	// Avoid running the pointer analysis for static calls.
+	if callee := site.Common().StaticCallee(); callee != nil {
+		switch callee.String() {
+		case "runtime.SetFinalizer", "(reflect.Value).Call":
+			// The PTA treats calls to these intrinsics as dynamic.
+			// TODO(adonovan): avoid reliance on PTA internals.
+
+		default:
+			return []*ssa.Function{callee}, nil // singleton
+		}
+	}
+
+	// Dynamic call: use pointer analysis.
+	conf.BuildCallGraph = true
+	cg := ptrAnalysis(conf).CallGraph
+	cg.DeleteSyntheticNodes()
+
+	// Find all call edges from the site.
+	n := cg.Nodes[site.Parent()]
+	if n == nil {
+		return nil, fmt.Errorf("this call site is unreachable in this analysis")
+	}
+	calleesMap := make(map[*ssa.Function]bool)
+	for _, edge := range n.Out {
+		if edge.Site == site {
+			calleesMap[edge.Callee.Func] = true
+		}
+	}
+
+	// De-duplicate and sort.
+	funcs := make([]*ssa.Function, 0, len(calleesMap))
+	for f := range calleesMap {
+		funcs = append(funcs, f)
+	}
+	sort.Sort(byFuncPos(funcs))
+	return funcs, nil
+}
+
+type calleesSSAResult struct {
+	site  ssa.CallInstruction
+	funcs []*ssa.Function
+}
+
+type calleesTypesResult struct {
+	site   *ast.CallExpr
+	callee *types.Func
+}
+
+func (r *calleesSSAResult) display(printf printfFunc) {
+	if len(r.funcs) == 0 {
+		// dynamic call on a provably nil func/interface
+		printf(r.site, "%s on nil value", r.site.Common().Description())
+	} else {
+		printf(r.site, "this %s dispatches to:", r.site.Common().Description())
+		for _, callee := range r.funcs {
+			printf(callee, "\t%s", callee)
+		}
+	}
+}
+
+func (r *calleesSSAResult) toSerial(res *serial.Result, fset *token.FileSet) {
+	j := &serial.Callees{
+		Pos:  fset.Position(r.site.Pos()).String(),
+		Desc: r.site.Common().Description(),
+	}
+	for _, callee := range r.funcs {
+		j.Callees = append(j.Callees, &serial.CalleesItem{
+			Name: callee.String(),
+			Pos:  fset.Position(callee.Pos()).String(),
+		})
+	}
+	res.Callees = j
+}
+
+func (r *calleesTypesResult) display(printf printfFunc) {
+	printf(r.site, "this static function call dispatches to:")
+	printf(r.callee, "\t%s", r.callee.FullName())
+}
+
+func (r *calleesTypesResult) toSerial(res *serial.Result, fset *token.FileSet) {
+	j := &serial.Callees{
+		Pos:  fset.Position(r.site.Pos()).String(),
+		Desc: "static function call",
+	}
+	j.Callees = []*serial.CalleesItem{
+		&serial.CalleesItem{
+			Name: r.callee.FullName(),
+			Pos:  fset.Position(r.callee.Pos()).String(),
+		},
+	}
+	res.Callees = j
+}
+
+// NB: byFuncPos is not deterministic across packages since it depends on load order.
+// Use lessPos if the tests need it.
+type byFuncPos []*ssa.Function
+
+func (a byFuncPos) Len() int           { return len(a) }
+func (a byFuncPos) Less(i, j int) bool { return a[i].Pos() < a[j].Pos() }
+func (a byFuncPos) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }

vendor/github.com/visualfc/gotools/oracle/oracle/callers.go

@@ -0,0 +1,115 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package oracle
+
+import (
+	"fmt"
+	"go/token"
+
+	"github.com/visualfc/gotools/oracle/oracle/serial"
+	"golang.org/x/tools/go/callgraph"
+	"golang.org/x/tools/go/loader"
+	"golang.org/x/tools/go/ssa"
+	"golang.org/x/tools/go/ssa/ssautil"
+)
+
+// Callers reports the possible callers of the function
+// immediately enclosing the specified source location.
+//
+func callers(q *Query) error {
+	lconf := loader.Config{Build: q.Build}
+
+	if err := setPTAScope(&lconf, q.Scope); err != nil {
+		return err
+	}
+
+	// Load/parse/type-check the program.
+	lprog, err := lconf.Load()
+	if err != nil {
+		return err
+	}
+	q.Fset = lprog.Fset
+
+	qpos, err := parseQueryPos(lprog, q.Pos, false)
+	if err != nil {
+		return err
+	}
+
+	prog := ssautil.CreateProgram(lprog, 0)
+
+	ptaConfig, err := setupPTA(prog, lprog, q.PTALog, q.Reflection)
+	if err != nil {
+		return err
+	}
+
+	pkg := prog.Package(qpos.info.Pkg)
+	if pkg == nil {
+		return fmt.Errorf("no SSA package")
+	}
+	if !ssa.HasEnclosingFunction(pkg, qpos.path) {
+		return fmt.Errorf("this position is not inside a function")
+	}
+
+	// Defer SSA construction till after errors are reported.
+	prog.Build()
+
+	target := ssa.EnclosingFunction(pkg, qpos.path)
+	if target == nil {
+		return fmt.Errorf("no SSA function built for this location (dead code?)")
+	}
+
+	// TODO(adonovan): opt: if function is never address-taken, skip
+	// the pointer analysis.  Just look for direct calls.  This can
+	// be done in a single pass over the SSA.
+
+	// Run the pointer analysis, recording each
+	// call found to originate from target.
+	ptaConfig.BuildCallGraph = true
+	cg := ptrAnalysis(ptaConfig).CallGraph
+	cg.DeleteSyntheticNodes()
+	edges := cg.CreateNode(target).In
+	// TODO(adonovan): sort + dedup calls to ensure test determinism.
+
+	q.result = &callersResult{
+		target:    target,
+		callgraph: cg,
+		edges:     edges,
+	}
+	return nil
+}
+
+type callersResult struct {
+	target    *ssa.Function
+	callgraph *callgraph.Graph
+	edges     []*callgraph.Edge
+}
+
+func (r *callersResult) display(printf printfFunc) {
+	root := r.callgraph.Root
+	if r.edges == nil {
+		printf(r.target, "%s is not reachable in this program.", r.target)
+	} else {
+		printf(r.target, "%s is called from these %d sites:", r.target, len(r.edges))
+		for _, edge := range r.edges {
+			if edge.Caller == root {
+				printf(r.target, "the root of the call graph")
+			} else {
+				printf(edge, "\t%s from %s", edge.Description(), edge.Caller.Func)
+			}
+		}
+	}
+}
+
+func (r *callersResult) toSerial(res *serial.Result, fset *token.FileSet) {
+	var callers []serial.Caller
+	for _, edge := range r.edges {
+		callers = append(callers, serial.Caller{
+			Caller: edge.Caller.Func.String(),
+			Pos:    fset.Position(edge.Pos()).String(),
+			Desc:   edge.Description(),
+		})
+	}
+	res.Callers = callers
+}

vendor/github.com/visualfc/gotools/oracle/oracle/callstack.go

@@ -0,0 +1,126 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package oracle
+
+import (
+	"fmt"
+	"go/token"
+
+	"github.com/visualfc/gotools/oracle/oracle/serial"
+	"golang.org/x/tools/go/callgraph"
+	"golang.org/x/tools/go/loader"
+	"golang.org/x/tools/go/ssa"
+	"golang.org/x/tools/go/ssa/ssautil"
+)
+
+// Callstack displays an arbitrary path from a root of the callgraph
+// to the function at the current position.
+//
+// The information may be misleading in a context-insensitive
+// analysis. e.g. the call path X->Y->Z might be infeasible if Y never
+// calls Z when it is called from X.  TODO(adonovan): think about UI.
+//
+// TODO(adonovan): permit user to specify a starting point other than
+// the analysis root.
+//
+func callstack(q *Query) error {
+	fset := token.NewFileSet()
+	lconf := loader.Config{Fset: fset, Build: q.Build}
+
+	if err := setPTAScope(&lconf, q.Scope); err != nil {
+		return err
+	}
+
+	// Load/parse/type-check the program.
+	lprog, err := lconf.Load()
+	if err != nil {
+		return err
+	}
+
+	qpos, err := parseQueryPos(lprog, q.Pos, false)
+	if err != nil {
+		return err
+	}
+
+	prog := ssautil.CreateProgram(lprog, 0)
+
+	ptaConfig, err := setupPTA(prog, lprog, q.PTALog, q.Reflection)
+	if err != nil {
+		return err
+	}
+
+	pkg := prog.Package(qpos.info.Pkg)
+	if pkg == nil {
+		return fmt.Errorf("no SSA package")
+	}
+
+	if !ssa.HasEnclosingFunction(pkg, qpos.path) {
+		return fmt.Errorf("this position is not inside a function")
+	}
+
+	// Defer SSA construction till after errors are reported.
+	prog.Build()
+
+	target := ssa.EnclosingFunction(pkg, qpos.path)
+	if target == nil {
+		return fmt.Errorf("no SSA function built for this location (dead code?)")
+	}
+
+	// Run the pointer analysis and build the complete call graph.
+	ptaConfig.BuildCallGraph = true
+	cg := ptrAnalysis(ptaConfig).CallGraph
+	cg.DeleteSyntheticNodes()
+
+	// Search for an arbitrary path from a root to the target function.
+	isEnd := func(n *callgraph.Node) bool { return n.Func == target }
+	callpath := callgraph.PathSearch(cg.Root, isEnd)
+	if callpath != nil {
+		callpath = callpath[1:] // remove synthetic edge from <root>
+	}
+
+	q.Fset = fset
+	q.result = &callstackResult{
+		qpos:     qpos,
+		target:   target,
+		callpath: callpath,
+	}
+	return nil
+}
+
+type callstackResult struct {
+	qpos     *queryPos
+	target   *ssa.Function
+	callpath []*callgraph.Edge
+}
+
+func (r *callstackResult) display(printf printfFunc) {
+	if r.callpath != nil {
+		printf(r.qpos, "Found a call path from root to %s", r.target)
+		printf(r.target, "%s", r.target)
+		for i := len(r.callpath) - 1; i >= 0; i-- {
+			edge := r.callpath[i]
+			printf(edge, "%s from %s", edge.Description(), edge.Caller.Func)
+		}
+	} else {
+		printf(r.target, "%s is unreachable in this analysis scope", r.target)
+	}
+}
+
+func (r *callstackResult) toSerial(res *serial.Result, fset *token.FileSet) {
+	var callers []serial.Caller
+	for i := len(r.callpath) - 1; i >= 0; i-- { // (innermost first)
+		edge := r.callpath[i]
+		callers = append(callers, serial.Caller{
+			Pos:    fset.Position(edge.Pos()).String(),
+			Caller: edge.Caller.Func.String(),
+			Desc:   edge.Description(),
+		})
+	}
+	res.Callstack = &serial.CallStack{
+		Pos:     fset.Position(r.target.Pos()).String(),
+		Target:  r.target.String(),
+		Callers: callers,
+	}
+}

vendor/github.com/visualfc/gotools/oracle/oracle/definition.go

@@ -0,0 +1,78 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build go1.5
+
+package oracle
+
+import (
+	"fmt"
+	"go/ast"
+	"go/token"
+	"go/types"
+
+	"github.com/visualfc/gotools/oracle/oracle/serial"
+	"golang.org/x/tools/go/loader"
+)
+
+// definition reports the location of the definition of an identifier.
+//
+// TODO(adonovan): opt: for intra-file references, the parser's
+// resolution might be enough; we should start with that.
+//
+func definition(q *Query) error {
+	lconf := loader.Config{Build: q.Build}
+	allowErrors(&lconf)
+
+	if _, err := importQueryPackage(q.Pos, &lconf); err != nil {
+		return err
+	}
+
+	// Load/parse/type-check the program.
+	lprog, err := lconf.Load()
+	if err != nil {
+		return err
+	}
+	q.Fset = lprog.Fset
+
+	qpos, err := parseQueryPos(lprog, q.Pos, false)
+	if err != nil {
+		return err
+	}
+
+	id, _ := qpos.path[0].(*ast.Ident)
+	if id == nil {
+		return fmt.Errorf("no identifier here")
+	}
+
+	obj := qpos.info.ObjectOf(id)
+	if obj == nil {
+		// Happens for y in "switch y := x.(type)",
+		// and the package declaration,
+		// but I think that's all.
+		return fmt.Errorf("no object for identifier")
+	}
+
+	q.result = &definitionResult{qpos, obj}
+	return nil
+}
+
+type definitionResult struct {
+	qpos *queryPos
+	obj  types.Object // object it denotes
+}
+
+func (r *definitionResult) display(printf printfFunc) {
+	printf(r.obj, "defined here as %s", r.qpos.objectString(r.obj))
+}
+
+func (r *definitionResult) toSerial(res *serial.Result, fset *token.FileSet) {
+	definition := &serial.Definition{
+		Desc: r.obj.String(),
+	}
+	if pos := r.obj.Pos(); pos != token.NoPos { // Package objects have no Pos()
+		definition.ObjPos = fset.Position(pos).String()
+	}
+	res.Definition = definition
+}

vendor/github.com/visualfc/gotools/oracle/oracle/describe.go

@@ -0,0 +1,775 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build go1.6
+
+package oracle
+
+import (
+	"bytes"
+	"fmt"
+	"go/ast"
+	exact "go/constant"
+	"go/token"
+	"go/types"
+	"log"
+	"os"
+	"strings"
+
+	"github.com/visualfc/gotools/oracle/oracle/serial"
+	"golang.org/x/tools/go/ast/astutil"
+	"golang.org/x/tools/go/loader"
+	"golang.org/x/tools/go/types/typeutil"
+)
+
+// describe describes the syntax node denoted by the query position,
+// including:
+// - its syntactic category
+// - the definition of its referent (for identifiers) [now redundant]
+// - its type and method set (for an expression or type expression)
+//
+func describe(q *Query) error {
+	lconf := loader.Config{Build: q.Build}
+	allowErrors(&lconf)
+
+	if _, err := importQueryPackage(q.Pos, &lconf); err != nil {
+		return err
+	}
+
+	// Load/parse/type-check the program.
+	lprog, err := lconf.Load()
+	if err != nil {
+		return err
+	}
+	q.Fset = lprog.Fset
+
+	qpos, err := parseQueryPos(lprog, q.Pos, true) // (need exact pos)
+	if err != nil {
+		return err
+	}
+
+	if false { // debugging
+		fprintf(os.Stderr, lprog.Fset, qpos.path[0], "you selected: %s %s",
+			astutil.NodeDescription(qpos.path[0]), pathToString(qpos.path))
+	}
+
+	path, action := findInterestingNode(qpos.info, qpos.path)
+	switch action {
+	case actionExpr:
+		q.result, err = describeValue(qpos, path)
+
+	case actionType:
+		q.result, err = describeType(qpos, path)
+
+	case actionPackage:
+		q.result, err = describePackage(qpos, path)
+
+	case actionStmt:
+		q.result, err = describeStmt(qpos, path)
+
+	case actionUnknown:
+		q.result = &describeUnknownResult{path[0]}
+
+	default:
+		panic(action) // unreachable
+	}
+	return err
+}
+
+type describeUnknownResult struct {
+	node ast.Node
+}
+
+func (r *describeUnknownResult) display(printf printfFunc) {
+	// Nothing much to say about misc syntax.
+	printf(r.node, "%s", astutil.NodeDescription(r.node))
+}
+
+func (r *describeUnknownResult) toSerial(res *serial.Result, fset *token.FileSet) {
+	res.Describe = &serial.Describe{
+		Desc: astutil.NodeDescription(r.node),
+		Pos:  fset.Position(r.node.Pos()).String(),
+	}
+}
+
+type action int
+
+const (
+	actionUnknown action = iota // None of the below
+	actionExpr                  // FuncDecl, true Expr or Ident(types.{Const,Var})
+	actionType                  // type Expr or Ident(types.TypeName).
+	actionStmt                  // Stmt or Ident(types.Label)
+	actionPackage               // Ident(types.Package) or ImportSpec
+)
+
+// findInterestingNode classifies the syntax node denoted by path as one of:
+//    - an expression, part of an expression or a reference to a constant
+//      or variable;
+//    - a type, part of a type, or a reference to a named type;
+//    - a statement, part of a statement, or a label referring to a statement;
+//    - part of a package declaration or import spec.
+//    - none of the above.
+// and returns the most "interesting" associated node, which may be
+// the same node, an ancestor or a descendent.
+//
+func findInterestingNode(pkginfo *loader.PackageInfo, path []ast.Node) ([]ast.Node, action) {
+	// TODO(adonovan): integrate with go/types/stdlib_test.go and
+	// apply this to every AST node we can find to make sure it
+	// doesn't crash.
+
+	// TODO(adonovan): audit for ParenExpr safety, esp. since we
+	// traverse up and down.
+
+	// TODO(adonovan): if the users selects the "." in
+	// "fmt.Fprintf()", they'll get an ambiguous selection error;
+	// we won't even reach here.  Can we do better?
+
+	// TODO(adonovan): describing a field within 'type T struct {...}'
+	// describes the (anonymous) struct type and concludes "no methods".
+	// We should ascend to the enclosing type decl, if any.
+
+	for len(path) > 0 {
+		switch n := path[0].(type) {
+		case *ast.GenDecl:
+			if len(n.Specs) == 1 {
+				// Descend to sole {Import,Type,Value}Spec child.
+				path = append([]ast.Node{n.Specs[0]}, path...)
+				continue
+			}
+			return path, actionUnknown // uninteresting
+
+		case *ast.FuncDecl:
+			// Descend to function name.
+			path = append([]ast.Node{n.Name}, path...)
+			continue
+
+		case *ast.ImportSpec:
+			return path, actionPackage
+
+		case *ast.ValueSpec:
+			if len(n.Names) == 1 {
+				// Descend to sole Ident child.
+				path = append([]ast.Node{n.Names[0]}, path...)
+				continue
+			}
+			return path, actionUnknown // uninteresting
+
+		case *ast.TypeSpec:
+			// Descend to type name.
+			path = append([]ast.Node{n.Name}, path...)
+			continue
+
+		case ast.Stmt:
+			return path, actionStmt
+
+		case *ast.ArrayType,
+			*ast.StructType,
+			*ast.FuncType,
+			*ast.InterfaceType,
+			*ast.MapType,
+			*ast.ChanType:
+			return path, actionType
+
+		case *ast.Comment, *ast.CommentGroup, *ast.File, *ast.KeyValueExpr, *ast.CommClause:
+			return path, actionUnknown // uninteresting
+
+		case *ast.Ellipsis:
+			// Continue to enclosing node.
+			// e.g. [...]T in ArrayType
+			//      f(x...) in CallExpr
+			//      f(x...T) in FuncType
+
+		case *ast.Field:
+			// TODO(adonovan): this needs more thought,
+			// since fields can be so many things.
+			if len(n.Names) == 1 {
+				// Descend to sole Ident child.
+				path = append([]ast.Node{n.Names[0]}, path...)
+				continue
+			}
+			// Zero names (e.g. anon field in struct)
+			// or multiple field or param names:
+			// continue to enclosing field list.
+
+		case *ast.FieldList:
+			// Continue to enclosing node:
+			// {Struct,Func,Interface}Type or FuncDecl.
+
+		case *ast.BasicLit:
+			if _, ok := path[1].(*ast.ImportSpec); ok {
+				return path[1:], actionPackage
+			}
+			return path, actionExpr
+
+		case *ast.SelectorExpr:
+			// TODO(adonovan): use Selections info directly.
+			if pkginfo.Uses[n.Sel] == nil {
+				// TODO(adonovan): is this reachable?
+				return path, actionUnknown
+			}
+			// Descend to .Sel child.
+			path = append([]ast.Node{n.Sel}, path...)
+			continue
+
+		case *ast.Ident:
+			switch pkginfo.ObjectOf(n).(type) {
+			case *types.PkgName:
+				return path, actionPackage
+
+			case *types.Const:
+				return path, actionExpr
+
+			case *types.Label:
+				return path, actionStmt
+
+			case *types.TypeName:
+				return path, actionType
+
+			case *types.Var:
+				// For x in 'struct {x T}', return struct type, for now.
+				if _, ok := path[1].(*ast.Field); ok {
+					_ = path[2].(*ast.FieldList) // assertion
+					if _, ok := path[3].(*ast.StructType); ok {
+						return path[3:], actionType
+					}
+				}
+				return path, actionExpr
+
+			case *types.Func:
+				return path, actionExpr
+
+			case *types.Builtin:
+				// For reference to built-in function, return enclosing call.
+				path = path[1:] // ascend to enclosing function call
+				continue
+
+			case *types.Nil:
+				return path, actionExpr
+			}
+
+			// No object.
+			switch path[1].(type) {
+			case *ast.SelectorExpr:
+				// Return enclosing selector expression.
+				return path[1:], actionExpr
+
+			case *ast.Field:
+				// TODO(adonovan): test this.
+				// e.g. all f in:
+				//  struct { f, g int }
+				//  interface { f() }
+				//  func (f T) method(f, g int) (f, g bool)
+				//
+				// switch path[3].(type) {
+				// case *ast.FuncDecl:
+				// case *ast.StructType:
+				// case *ast.InterfaceType:
+				// }
+				//
+				// return path[1:], actionExpr
+				//
+				// Unclear what to do with these.
+				// Struct.Fields             -- field
+				// Interface.Methods         -- field
+				// FuncType.{Params.Results} -- actionExpr
+				// FuncDecl.Recv             -- actionExpr
+
+			case *ast.File:
+				// 'package foo'
+				return path, actionPackage
+
+			case *ast.ImportSpec:
+				// TODO(adonovan): fix: why no package object? go/types bug?
+				return path[1:], actionPackage
+
+			default:
+				// e.g. blank identifier
+				// or y in "switch y := x.(type)"
+				// or code in a _test.go file that's not part of the package.
+				log.Printf("unknown reference %s in %T\n", n, path[1])
+				return path, actionUnknown
+			}
+
+		case *ast.StarExpr:
+			if pkginfo.Types[n].IsType() {
+				return path, actionType
+			}
+			return path, actionExpr
+
+		case ast.Expr:
+			// All Expr but {BasicLit,Ident,StarExpr} are
+			// "true" expressions that evaluate to a value.
+			return path, actionExpr
+		}
+
+		// Ascend to parent.
+		path = path[1:]
+	}
+
+	return nil, actionUnknown // unreachable
+}
+
+func describeValue(qpos *queryPos, path []ast.Node) (*describeValueResult, error) {
+	var expr ast.Expr
+	var obj types.Object
+	switch n := path[0].(type) {
+	case *ast.ValueSpec:
+		// ambiguous ValueSpec containing multiple names
+		return nil, fmt.Errorf("multiple value specification")
+	case *ast.Ident:
+		obj = qpos.info.ObjectOf(n)
+		expr = n
+	case ast.Expr:
+		expr = n
+	default:
+		// TODO(adonovan): is this reachable?
+		return nil, fmt.Errorf("unexpected AST for expr: %T", n)
+	}
+
+	typ := qpos.info.TypeOf(expr)
+	constVal := qpos.info.Types[expr].Value
+
+	return &describeValueResult{
+		qpos:     qpos,
+		expr:     expr,
+		typ:      typ,
+		constVal: constVal,
+		obj:      obj,
+	}, nil
+}
+
+type describeValueResult struct {
+	qpos     *queryPos
+	expr     ast.Expr     // query node
+	typ      types.Type   // type of expression
+	constVal exact.Value  // value of expression, if constant
+	obj      types.Object // var/func/const object, if expr was Ident
+}
+
+func (r *describeValueResult) display(printf printfFunc) {
+	var prefix, suffix string
+	if r.constVal != nil {
+		suffix = fmt.Sprintf(" of constant value %s", r.constVal)
+	}
+	switch obj := r.obj.(type) {
+	case *types.Func:
+		if recv := obj.Type().(*types.Signature).Recv(); recv != nil {
+			if _, ok := recv.Type().Underlying().(*types.Interface); ok {
+				prefix = "interface method "
+			} else {
+				prefix = "method "
+			}
+		}
+	}
+
+	// Describe the expression.
+	if r.obj != nil {
+		if r.obj.Pos() == r.expr.Pos() {
+			// defining ident
+			printf(r.expr, "definition of %s%s%s", prefix, r.qpos.objectString(r.obj), suffix)
+		} else {
+			// referring ident
+			printf(r.expr, "reference to %s%s%s", prefix, r.qpos.objectString(r.obj), suffix)
+			if def := r.obj.Pos(); def != token.NoPos {
+				printf(def, "defined here")
+			}
+		}
+	} else {
+		desc := astutil.NodeDescription(r.expr)
+		if suffix != "" {
+			// constant expression
+			printf(r.expr, "%s%s", desc, suffix)
+		} else {
+			// non-constant expression
+			printf(r.expr, "%s of type %s", desc, r.qpos.typeString(r.typ))
+		}
+	}
+}
+
+func (r *describeValueResult) toSerial(res *serial.Result, fset *token.FileSet) {
+	var value, objpos string
+	if r.constVal != nil {
+		value = r.constVal.String()
+	}
+	if r.obj != nil {
+		objpos = fset.Position(r.obj.Pos()).String()
+	}
+
+	res.Describe = &serial.Describe{
+		Desc:   astutil.NodeDescription(r.expr),
+		Pos:    fset.Position(r.expr.Pos()).String(),
+		Detail: "value",
+		Value: &serial.DescribeValue{
+			Type:   r.qpos.typeString(r.typ),
+			Value:  value,
+			ObjPos: objpos,
+		},
+	}
+}
+
+// ---- TYPE ------------------------------------------------------------
+
+func describeType(qpos *queryPos, path []ast.Node) (*describeTypeResult, error) {
+	var description string
+	var t types.Type
+	switch n := path[0].(type) {
+	case *ast.Ident:
+		t = qpos.info.TypeOf(n)
+		switch t := t.(type) {
+		case *types.Basic:
+			description = "reference to built-in "
+
+		case *types.Named:
+			isDef := t.Obj().Pos() == n.Pos() // see caveats at isDef above
+			if isDef {
+				description = "definition of "
+			} else {
+				description = "reference to "
+			}
+		}
+
+	case ast.Expr:
+		t = qpos.info.TypeOf(n)
+
+	default:
+		// Unreachable?
+		return nil, fmt.Errorf("unexpected AST for type: %T", n)
+	}
+
+	description = description + "type " + qpos.typeString(t)
+
+	// Show sizes for structs and named types (it's fairly obvious for others).
+	switch t.(type) {
+	case *types.Named, *types.Struct:
+		szs := types.StdSizes{WordSize: 8, MaxAlign: 8} // assume amd64
+		description = fmt.Sprintf("%s (size %d, align %d)", description,
+			szs.Sizeof(t), szs.Alignof(t))
+	}
+
+	return &describeTypeResult{
+		qpos:        qpos,
+		node:        path[0],
+		description: description,
+		typ:         t,
+		methods:     accessibleMethods(t, qpos.info.Pkg),
+	}, nil
+}
+
+type describeTypeResult struct {
+	qpos        *queryPos
+	node        ast.Node
+	description string
+	typ         types.Type
+	methods     []*types.Selection
+}
+
+func (r *describeTypeResult) display(printf printfFunc) {
+	printf(r.node, "%s", r.description)
+
+	// Show the underlying type for a reference to a named type.
+	if nt, ok := r.typ.(*types.Named); ok && r.node.Pos() != nt.Obj().Pos() {
+		printf(nt.Obj(), "defined as %s", r.qpos.typeString(nt.Underlying()))
+	}
+
+	// Print the method set, if the type kind is capable of bearing methods.
+	switch r.typ.(type) {
+	case *types.Interface, *types.Struct, *types.Named:
+		if len(r.methods) > 0 {
+			printf(r.node, "Method set:")
+			for _, meth := range r.methods {
+				// TODO(adonovan): print these relative
+				// to the owning package, not the
+				// query package.
+				printf(meth.Obj(), "\t%s", r.qpos.selectionString(meth))
+			}
+		} else {
+			printf(r.node, "No methods.")
+		}
+	}
+}
+
+func (r *describeTypeResult) toSerial(res *serial.Result, fset *token.FileSet) {
+	var namePos, nameDef string
+	if nt, ok := r.typ.(*types.Named); ok {
+		namePos = fset.Position(nt.Obj().Pos()).String()
+		nameDef = nt.Underlying().String()
+	}
+	res.Describe = &serial.Describe{
+		Desc:   r.description,
+		Pos:    fset.Position(r.node.Pos()).String(),
+		Detail: "type",
+		Type: &serial.DescribeType{
+			Type:    r.qpos.typeString(r.typ),
+			NamePos: namePos,
+			NameDef: nameDef,
+			Methods: methodsToSerial(r.qpos.info.Pkg, r.methods, fset),
+		},
+	}
+}
+
+// ---- PACKAGE ------------------------------------------------------------
+
+func describePackage(qpos *queryPos, path []ast.Node) (*describePackageResult, error) {
+	var description string
+	var pkg *types.Package
+	switch n := path[0].(type) {
+	case *ast.ImportSpec:
+		var obj types.Object
+		if n.Name != nil {
+			obj = qpos.info.Defs[n.Name]
+		} else {
+			obj = qpos.info.Implicits[n]
+		}
+		pkgname, _ := obj.(*types.PkgName)
+		if pkgname == nil {
+			return nil, fmt.Errorf("can't import package %s", n.Path.Value)
+		}
+		pkg = pkgname.Imported()
+		description = fmt.Sprintf("import of package %q", pkg.Path())
+
+	case *ast.Ident:
+		if _, isDef := path[1].(*ast.File); isDef {
+			// e.g. package id
+			pkg = qpos.info.Pkg
+			description = fmt.Sprintf("definition of package %q", pkg.Path())
+		} else {
+			// e.g. import id "..."
+			//  or  id.F()
+			pkg = qpos.info.ObjectOf(n).(*types.PkgName).Imported()
+			description = fmt.Sprintf("reference to package %q", pkg.Path())
+		}
+
+	default:
+		// Unreachable?
+		return nil, fmt.Errorf("unexpected AST for package: %T", n)
+	}
+
+	var members []*describeMember
+	// NB: "unsafe" has no types.Package
+	if pkg != nil {
+		// Enumerate the accessible package members
+		// in lexicographic order.
+		for _, name := range pkg.Scope().Names() {
+			if pkg == qpos.info.Pkg || ast.IsExported(name) {
+				mem := pkg.Scope().Lookup(name)
+				var methods []*types.Selection
+				if mem, ok := mem.(*types.TypeName); ok {
+					methods = accessibleMethods(mem.Type(), qpos.info.Pkg)
+				}
+				members = append(members, &describeMember{
+					mem,
+					methods,
+				})
+
+			}
+		}
+	}
+
+	return &describePackageResult{qpos.fset, path[0], description, pkg, members}, nil
+}
+
+type describePackageResult struct {
+	fset        *token.FileSet
+	node        ast.Node
+	description string
+	pkg         *types.Package
+	members     []*describeMember // in lexicographic name order
+}
+
+type describeMember struct {
+	obj     types.Object
+	methods []*types.Selection // in types.MethodSet order
+}
+
+func (r *describePackageResult) display(printf printfFunc) {
+	printf(r.node, "%s", r.description)
+
+	// Compute max width of name "column".
+	maxname := 0
+	for _, mem := range r.members {
+		if l := len(mem.obj.Name()); l > maxname {
+			maxname = l
+		}
+	}
+
+	for _, mem := range r.members {
+		printf(mem.obj, "\t%s", formatMember(mem.obj, maxname))
+		for _, meth := range mem.methods {
+			printf(meth.Obj(), "\t\t%s", types.SelectionString(meth, types.RelativeTo(r.pkg)))
+		}
+	}
+}
+
+func formatMember(obj types.Object, maxname int) string {
+	qualifier := types.RelativeTo(obj.Pkg())
+	var buf bytes.Buffer
+	fmt.Fprintf(&buf, "%-5s %-*s", tokenOf(obj), maxname, obj.Name())
+	switch obj := obj.(type) {
+	case *types.Const:
+		fmt.Fprintf(&buf, " %s = %s", types.TypeString(obj.Type(), qualifier), obj.Val().String())
+
+	case *types.Func:
+		fmt.Fprintf(&buf, " %s", types.TypeString(obj.Type(), qualifier))
+
+	case *types.TypeName:
+		// Abbreviate long aggregate type names.
+		var abbrev string
+		switch t := obj.Type().Underlying().(type) {
+		case *types.Interface:
+			if t.NumMethods() > 1 {
+				abbrev = "interface{...}"
+			}
+		case *types.Struct:
+			if t.NumFields() > 1 {
+				abbrev = "struct{...}"
+			}
+		}
+		if abbrev == "" {
+			fmt.Fprintf(&buf, " %s", types.TypeString(obj.Type().Underlying(), qualifier))
+		} else {
+			fmt.Fprintf(&buf, " %s", abbrev)
+		}
+
+	case *types.Var:
+		fmt.Fprintf(&buf, " %s", types.TypeString(obj.Type(), qualifier))
+	}
+	return buf.String()
+}
+
+func (r *describePackageResult) toSerial(res *serial.Result, fset *token.FileSet) {
+	var members []*serial.DescribeMember
+	for _, mem := range r.members {
+		typ := mem.obj.Type()
+		var val string
+		switch mem := mem.obj.(type) {
+		case *types.Const:
+			val = mem.Val().String()
+		case *types.TypeName:
+			typ = typ.Underlying()
+		}
+		members = append(members, &serial.DescribeMember{
+			Name:    mem.obj.Name(),
+			Type:    typ.String(),
+			Value:   val,
+			Pos:     fset.Position(mem.obj.Pos()).String(),
+			Kind:    tokenOf(mem.obj),
+			Methods: methodsToSerial(r.pkg, mem.methods, fset),
+		})
+	}
+	res.Describe = &serial.Describe{
+		Desc:   r.description,
+		Pos:    fset.Position(r.node.Pos()).String(),
+		Detail: "package",
+		Package: &serial.DescribePackage{
+			Path:    r.pkg.Path(),
+			Members: members,
+		},
+	}
+}
+
+func tokenOf(o types.Object) string {
+	switch o.(type) {
+	case *types.Func:
+		return "func"
+	case *types.Var:
+		return "var"
+	case *types.TypeName:
+		return "type"
+	case *types.Const:
+		return "const"
+	case *types.PkgName:
+		return "package"
+	case *types.Builtin:
+		return "builtin" // e.g. when describing package "unsafe"
+	case *types.Nil:
+		return "nil"
+	case *types.Label:
+		return "label"
+	}
+	panic(o)
+}
+
+// ---- STATEMENT ------------------------------------------------------------
+
+func describeStmt(qpos *queryPos, path []ast.Node) (*describeStmtResult, error) {
+	var description string
+	switch n := path[0].(type) {
+	case *ast.Ident:
+		if qpos.info.Defs[n] != nil {
+			description = "labelled statement"
+		} else {
+			description = "reference to labelled statement"
+		}
+
+	default:
+		// Nothing much to say about statements.
+		description = astutil.NodeDescription(n)
+	}
+	return &describeStmtResult{qpos.fset, path[0], description}, nil
+}
+
+type describeStmtResult struct {
+	fset        *token.FileSet
+	node        ast.Node
+	description string
+}
+
+func (r *describeStmtResult) display(printf printfFunc) {
+	printf(r.node, "%s", r.description)
+}
+
+func (r *describeStmtResult) toSerial(res *serial.Result, fset *token.FileSet) {
+	res.Describe = &serial.Describe{
+		Desc:   r.description,
+		Pos:    fset.Position(r.node.Pos()).String(),
+		Detail: "unknown",
+	}
+}
+
+// ------------------- Utilities -------------------
+
+// pathToString returns a string containing the concrete types of the
+// nodes in path.
+func pathToString(path []ast.Node) string {
+	var buf bytes.Buffer
+	fmt.Fprint(&buf, "[")
+	for i, n := range path {
+		if i > 0 {
+			fmt.Fprint(&buf, " ")
+		}
+		fmt.Fprint(&buf, strings.TrimPrefix(fmt.Sprintf("%T", n), "*ast."))
+	}
+	fmt.Fprint(&buf, "]")
+	return buf.String()
+}
+
+func accessibleMethods(t types.Type, from *types.Package) []*types.Selection {
+	var methods []*types.Selection
+	for _, meth := range typeutil.IntuitiveMethodSet(t, nil) {
+		if isAccessibleFrom(meth.Obj(), from) {
+			methods = append(methods, meth)
+		}
+	}
+	return methods
+}
+
+func isAccessibleFrom(obj types.Object, pkg *types.Package) bool {
+	return ast.IsExported(obj.Name()) || obj.Pkg() == pkg
+}
+
+func methodsToSerial(this *types.Package, methods []*types.Selection, fset *token.FileSet) []serial.DescribeMethod {
+	qualifier := types.RelativeTo(this)
+	var jmethods []serial.DescribeMethod
+	for _, meth := range methods {
+		var ser serial.DescribeMethod
+		if meth != nil { // may contain nils when called by implements (on a method)
+			ser = serial.DescribeMethod{
+				Name: types.SelectionString(meth, qualifier),
+				Pos:  fset.Position(meth.Obj().Pos()).String(),
+			}
+		}
+		jmethods = append(jmethods, ser)
+	}
+	return jmethods
+}

vendor/github.com/visualfc/gotools/oracle/oracle/describe15.go

@@ -0,0 +1,786 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build go1.5,!go1.6
+
+package oracle
+
+import (
+	"bytes"
+	"fmt"
+	"go/ast"
+	exact "go/constant"
+	"go/token"
+	"go/types"
+	"log"
+	"os"
+	"strings"
+
+	"github.com/visualfc/gotools/oracle/oracle/serial"
+	"golang.org/x/tools/go/ast/astutil"
+	"golang.org/x/tools/go/loader"
+	"golang.org/x/tools/go/types/typeutil"
+)
+
+// describe describes the syntax node denoted by the query position,
+// including:
+// - its syntactic category
+// - the definition of its referent (for identifiers) [now redundant]
+// - its type and method set (for an expression or type expression)
+//
+func describe(q *Query) error {
+	lconf := loader.Config{Build: q.Build}
+	allowErrors(&lconf)
+
+	if _, err := importQueryPackage(q.Pos, &lconf); err != nil {
+		return err
+	}
+
+	// Load/parse/type-check the program.
+	lprog, err := lconf.Load()
+	if err != nil {
+		return err
+	}
+	q.Fset = lprog.Fset
+
+	qpos, err := parseQueryPos(lprog, q.Pos, true) // (need exact pos)
+	if err != nil {
+		return err
+	}
+
+	if false { // debugging
+		fprintf(os.Stderr, lprog.Fset, qpos.path[0], "you selected: %s %s",
+			astutil.NodeDescription(qpos.path[0]), pathToString(qpos.path))
+	}
+
+	path, action := findInterestingNode(qpos.info, qpos.path)
+	switch action {
+	case actionExpr:
+		q.result, err = describeValue(qpos, path)
+
+	case actionType:
+		q.result, err = describeType(qpos, path)
+
+	case actionPackage:
+		q.result, err = describePackage(qpos, path)
+
+	case actionStmt:
+		q.result, err = describeStmt(qpos, path)
+
+	case actionUnknown:
+		q.result = &describeUnknownResult{path[0]}
+
+	default:
+		panic(action) // unreachable
+	}
+	return err
+}
+
+type describeUnknownResult struct {
+	node ast.Node
+}
+
+func (r *describeUnknownResult) display(printf printfFunc) {
+	// Nothing much to say about misc syntax.
+	printf(r.node, "%s", astutil.NodeDescription(r.node))
+}
+
+func (r *describeUnknownResult) toSerial(res *serial.Result, fset *token.FileSet) {
+	res.Describe = &serial.Describe{
+		Desc: astutil.NodeDescription(r.node),
+		Pos:  fset.Position(r.node.Pos()).String(),
+	}
+}
+
+type action int
+
+const (
+	actionUnknown action = iota // None of the below
+	actionExpr                  // FuncDecl, true Expr or Ident(types.{Const,Var})
+	actionType                  // type Expr or Ident(types.TypeName).
+	actionStmt                  // Stmt or Ident(types.Label)
+	actionPackage               // Ident(types.Package) or ImportSpec
+)
+
+// findInterestingNode classifies the syntax node denoted by path as one of:
+//    - an expression, part of an expression or a reference to a constant
+//      or variable;
+//    - a type, part of a type, or a reference to a named type;
+//    - a statement, part of a statement, or a label referring to a statement;
+//    - part of a package declaration or import spec.
+//    - none of the above.
+// and returns the most "interesting" associated node, which may be
+// the same node, an ancestor or a descendent.
+//
+func findInterestingNode(pkginfo *loader.PackageInfo, path []ast.Node) ([]ast.Node, action) {
+	// TODO(adonovan): integrate with go/types/stdlib_test.go and
+	// apply this to every AST node we can find to make sure it
+	// doesn't crash.
+
+	// TODO(adonovan): audit for ParenExpr safety, esp. since we
+	// traverse up and down.
+
+	// TODO(adonovan): if the users selects the "." in
+	// "fmt.Fprintf()", they'll get an ambiguous selection error;
+	// we won't even reach here.  Can we do better?
+
+	// TODO(adonovan): describing a field within 'type T struct {...}'
+	// describes the (anonymous) struct type and concludes "no methods".
+	// We should ascend to the enclosing type decl, if any.
+
+	for len(path) > 0 {
+		switch n := path[0].(type) {
+		case *ast.GenDecl:
+			if len(n.Specs) == 1 {
+				// Descend to sole {Import,Type,Value}Spec child.
+				path = append([]ast.Node{n.Specs[0]}, path...)
+				continue
+			}
+			return path, actionUnknown // uninteresting
+
+		case *ast.FuncDecl:
+			// Descend to function name.
+			path = append([]ast.Node{n.Name}, path...)
+			continue
+
+		case *ast.ImportSpec:
+			return path, actionPackage
+
+		case *ast.ValueSpec:
+			if len(n.Names) == 1 {
+				// Descend to sole Ident child.
+				path = append([]ast.Node{n.Names[0]}, path...)
+				continue
+			}
+			return path, actionUnknown // uninteresting
+
+		case *ast.TypeSpec:
+			// Descend to type name.
+			path = append([]ast.Node{n.Name}, path...)
+			continue
+
+		case ast.Stmt:
+			return path, actionStmt
+
+		case *ast.ArrayType,
+			*ast.StructType,
+			*ast.FuncType,
+			*ast.InterfaceType,
+			*ast.MapType,
+			*ast.ChanType:
+			return path, actionType
+
+		case *ast.Comment, *ast.CommentGroup, *ast.File, *ast.KeyValueExpr, *ast.CommClause:
+			return path, actionUnknown // uninteresting
+
+		case *ast.Ellipsis:
+			// Continue to enclosing node.
+			// e.g. [...]T in ArrayType
+			//      f(x...) in CallExpr
+			//      f(x...T) in FuncType
+
+		case *ast.Field:
+			// TODO(adonovan): this needs more thought,
+			// since fields can be so many things.
+			if len(n.Names) == 1 {
+				// Descend to sole Ident child.
+				path = append([]ast.Node{n.Names[0]}, path...)
+				continue
+			}
+			// Zero names (e.g. anon field in struct)
+			// or multiple field or param names:
+			// continue to enclosing field list.
+
+		case *ast.FieldList:
+			// Continue to enclosing node:
+			// {Struct,Func,Interface}Type or FuncDecl.
+
+		case *ast.BasicLit:
+			if _, ok := path[1].(*ast.ImportSpec); ok {
+				return path[1:], actionPackage
+			}
+			return path, actionExpr
+
+		case *ast.SelectorExpr:
+			// TODO(adonovan): use Selections info directly.
+			if pkginfo.Uses[n.Sel] == nil {
+				// TODO(adonovan): is this reachable?
+				return path, actionUnknown
+			}
+			// Descend to .Sel child.
+			path = append([]ast.Node{n.Sel}, path...)
+			continue
+
+		case *ast.Ident:
+			switch pkginfo.ObjectOf(n).(type) {
+			case *types.PkgName:
+				return path, actionPackage
+
+			case *types.Const:
+				return path, actionExpr
+
+			case *types.Label:
+				return path, actionStmt
+
+			case *types.TypeName:
+				return path, actionType
+
+			case *types.Var:
+				// For x in 'struct {x T}', return struct type, for now.
+				if _, ok := path[1].(*ast.Field); ok {
+					_ = path[2].(*ast.FieldList) // assertion
+					if _, ok := path[3].(*ast.StructType); ok {
+						return path[3:], actionType
+					}
+				}
+				return path, actionExpr
+
+			case *types.Func:
+				return path, actionExpr
+
+			case *types.Builtin:
+				// For reference to built-in function, return enclosing call.
+				path = path[1:] // ascend to enclosing function call
+				continue
+
+			case *types.Nil:
+				return path, actionExpr
+			}
+
+			// No object.
+			switch path[1].(type) {
+			case *ast.SelectorExpr:
+				// Return enclosing selector expression.
+				return path[1:], actionExpr
+
+			case *ast.Field:
+				// TODO(adonovan): test this.
+				// e.g. all f in:
+				//  struct { f, g int }
+				//  interface { f() }
+				//  func (f T) method(f, g int) (f, g bool)
+				//
+				// switch path[3].(type) {
+				// case *ast.FuncDecl:
+				// case *ast.StructType:
+				// case *ast.InterfaceType:
+				// }
+				//
+				// return path[1:], actionExpr
+				//
+				// Unclear what to do with these.
+				// Struct.Fields             -- field
+				// Interface.Methods         -- field
+				// FuncType.{Params.Results} -- actionExpr
+				// FuncDecl.Recv             -- actionExpr
+
+			case *ast.File:
+				// 'package foo'
+				return path, actionPackage
+
+			case *ast.ImportSpec:
+				// TODO(adonovan): fix: why no package object? go/types bug?
+				return path[1:], actionPackage
+
+			default:
+				// e.g. blank identifier
+				// or y in "switch y := x.(type)"
+				// or code in a _test.go file that's not part of the package.
+				log.Printf("unknown reference %s in %T\n", n, path[1])
+				return path, actionUnknown
+			}
+
+		case *ast.StarExpr:
+			if pkginfo.Types[n].IsType() {
+				return path, actionType
+			}
+			return path, actionExpr
+
+		case ast.Expr:
+			// All Expr but {BasicLit,Ident,StarExpr} are
+			// "true" expressions that evaluate to a value.
+			return path, actionExpr
+		}
+
+		// Ascend to parent.
+		path = path[1:]
+	}
+
+	return nil, actionUnknown // unreachable
+}
+
+func describeValue(qpos *queryPos, path []ast.Node) (*describeValueResult, error) {
+	var expr ast.Expr
+	var obj types.Object
+	switch n := path[0].(type) {
+	case *ast.ValueSpec:
+		// ambiguous ValueSpec containing multiple names
+		return nil, fmt.Errorf("multiple value specification")
+	case *ast.Ident:
+		obj = qpos.info.ObjectOf(n)
+		expr = n
+	case ast.Expr:
+		expr = n
+	default:
+		// TODO(adonovan): is this reachable?
+		return nil, fmt.Errorf("unexpected AST for expr: %T", n)
+	}
+
+	typ := qpos.info.TypeOf(expr)
+	constVal := qpos.info.Types[expr].Value
+
+	return &describeValueResult{
+		qpos:     qpos,
+		expr:     expr,
+		typ:      typ,
+		constVal: constVal,
+		obj:      obj,
+	}, nil
+}
+
+type describeValueResult struct {
+	qpos     *queryPos
+	expr     ast.Expr     // query node
+	typ      types.Type   // type of expression
+	constVal exact.Value  // value of expression, if constant
+	obj      types.Object // var/func/const object, if expr was Ident
+}
+
+func (r *describeValueResult) display(printf printfFunc) {
+	var prefix, suffix string
+	if r.constVal != nil {
+		suffix = fmt.Sprintf(" of constant value %s", constValString(r.constVal))
+	}
+	switch obj := r.obj.(type) {
+	case *types.Func:
+		if recv := obj.Type().(*types.Signature).Recv(); recv != nil {
+			if _, ok := recv.Type().Underlying().(*types.Interface); ok {
+				prefix = "interface method "
+			} else {
+				prefix = "method "
+			}
+		}
+	}
+
+	// Describe the expression.
+	if r.obj != nil {
+		if r.obj.Pos() == r.expr.Pos() {
+			// defining ident
+			printf(r.expr, "definition of %s%s%s", prefix, r.qpos.objectString(r.obj), suffix)
+		} else {
+			// referring ident
+			printf(r.expr, "reference to %s%s%s", prefix, r.qpos.objectString(r.obj), suffix)
+			if def := r.obj.Pos(); def != token.NoPos {
+				printf(def, "defined here")
+			}
+		}
+	} else {
+		desc := astutil.NodeDescription(r.expr)
+		if suffix != "" {
+			// constant expression
+			printf(r.expr, "%s%s", desc, suffix)
+		} else {
+			// non-constant expression
+			printf(r.expr, "%s of type %s", desc, r.qpos.typeString(r.typ))
+		}
+	}
+}
+
+func (r *describeValueResult) toSerial(res *serial.Result, fset *token.FileSet) {
+	var value, objpos string
+	if r.constVal != nil {
+		value = r.constVal.String()
+	}
+	if r.obj != nil {
+		objpos = fset.Position(r.obj.Pos()).String()
+	}
+
+	res.Describe = &serial.Describe{
+		Desc:   astutil.NodeDescription(r.expr),
+		Pos:    fset.Position(r.expr.Pos()).String(),
+		Detail: "value",
+		Value: &serial.DescribeValue{
+			Type:   r.qpos.typeString(r.typ),
+			Value:  value,
+			ObjPos: objpos,
+		},
+	}
+}
+
+// ---- TYPE ------------------------------------------------------------
+
+func describeType(qpos *queryPos, path []ast.Node) (*describeTypeResult, error) {
+	var description string
+	var t types.Type
+	switch n := path[0].(type) {
+	case *ast.Ident:
+		t = qpos.info.TypeOf(n)
+		switch t := t.(type) {
+		case *types.Basic:
+			description = "reference to built-in "
+
+		case *types.Named:
+			isDef := t.Obj().Pos() == n.Pos() // see caveats at isDef above
+			if isDef {
+				description = "definition of "
+			} else {
+				description = "reference to "
+			}
+		}
+
+	case ast.Expr:
+		t = qpos.info.TypeOf(n)
+
+	default:
+		// Unreachable?
+		return nil, fmt.Errorf("unexpected AST for type: %T", n)
+	}
+
+	description = description + "type " + qpos.typeString(t)
+
+	// Show sizes for structs and named types (it's fairly obvious for others).
+	switch t.(type) {
+	case *types.Named, *types.Struct:
+		szs := types.StdSizes{8, 8} // assume amd64
+		description = fmt.Sprintf("%s (size %d, align %d)", description,
+			szs.Sizeof(t), szs.Alignof(t))
+	}
+
+	return &describeTypeResult{
+		qpos:        qpos,
+		node:        path[0],
+		description: description,
+		typ:         t,
+		methods:     accessibleMethods(t, qpos.info.Pkg),
+	}, nil
+}
+
+type describeTypeResult struct {
+	qpos        *queryPos
+	node        ast.Node
+	description string
+	typ         types.Type
+	methods     []*types.Selection
+}
+
+func (r *describeTypeResult) display(printf printfFunc) {
+	printf(r.node, "%s", r.description)
+
+	// Show the underlying type for a reference to a named type.
+	if nt, ok := r.typ.(*types.Named); ok && r.node.Pos() != nt.Obj().Pos() {
+		printf(nt.Obj(), "defined as %s", r.qpos.typeString(nt.Underlying()))
+	}
+
+	// Print the method set, if the type kind is capable of bearing methods.
+	switch r.typ.(type) {
+	case *types.Interface, *types.Struct, *types.Named:
+		if len(r.methods) > 0 {
+			printf(r.node, "Method set:")
+			for _, meth := range r.methods {
+				// TODO(adonovan): print these relative
+				// to the owning package, not the
+				// query package.
+				printf(meth.Obj(), "\t%s", r.qpos.selectionString(meth))
+			}
+		} else {
+			printf(r.node, "No methods.")
+		}
+	}
+}
+
+func (r *describeTypeResult) toSerial(res *serial.Result, fset *token.FileSet) {
+	var namePos, nameDef string
+	if nt, ok := r.typ.(*types.Named); ok {
+		namePos = fset.Position(nt.Obj().Pos()).String()
+		nameDef = nt.Underlying().String()
+	}
+	res.Describe = &serial.Describe{
+		Desc:   r.description,
+		Pos:    fset.Position(r.node.Pos()).String(),
+		Detail: "type",
+		Type: &serial.DescribeType{
+			Type:    r.qpos.typeString(r.typ),
+			NamePos: namePos,
+			NameDef: nameDef,
+			Methods: methodsToSerial(r.qpos.info.Pkg, r.methods, fset),
+		},
+	}
+}
+
+// ---- PACKAGE ------------------------------------------------------------
+
+func describePackage(qpos *queryPos, path []ast.Node) (*describePackageResult, error) {
+	var description string
+	var pkg *types.Package
+	switch n := path[0].(type) {
+	case *ast.ImportSpec:
+		var obj types.Object
+		if n.Name != nil {
+			obj = qpos.info.Defs[n.Name]
+		} else {
+			obj = qpos.info.Implicits[n]
+		}
+		pkgname, _ := obj.(*types.PkgName)
+		if pkgname == nil {
+			return nil, fmt.Errorf("can't import package %s", n.Path.Value)
+		}
+		pkg = pkgname.Imported()
+		description = fmt.Sprintf("import of package %q", pkg.Path())
+
+	case *ast.Ident:
+		if _, isDef := path[1].(*ast.File); isDef {
+			// e.g. package id
+			pkg = qpos.info.Pkg
+			description = fmt.Sprintf("definition of package %q", pkg.Path())
+		} else {
+			// e.g. import id "..."
+			//  or  id.F()
+			pkg = qpos.info.ObjectOf(n).(*types.PkgName).Imported()
+			description = fmt.Sprintf("reference to package %q", pkg.Path())
+		}
+
+	default:
+		// Unreachable?
+		return nil, fmt.Errorf("unexpected AST for package: %T", n)
+	}
+
+	var members []*describeMember
+	// NB: "unsafe" has no types.Package
+	if pkg != nil {
+		// Enumerate the accessible package members
+		// in lexicographic order.
+		for _, name := range pkg.Scope().Names() {
+			if pkg == qpos.info.Pkg || ast.IsExported(name) {
+				mem := pkg.Scope().Lookup(name)
+				var methods []*types.Selection
+				if mem, ok := mem.(*types.TypeName); ok {
+					methods = accessibleMethods(mem.Type(), qpos.info.Pkg)
+				}
+				members = append(members, &describeMember{
+					mem,
+					methods,
+				})
+
+			}
+		}
+	}
+
+	return &describePackageResult{qpos.fset, path[0], description, pkg, members}, nil
+}
+
+type describePackageResult struct {
+	fset        *token.FileSet
+	node        ast.Node
+	description string
+	pkg         *types.Package
+	members     []*describeMember // in lexicographic name order
+}
+
+type describeMember struct {
+	obj     types.Object
+	methods []*types.Selection // in types.MethodSet order
+}
+
+func (r *describePackageResult) display(printf printfFunc) {
+	printf(r.node, "%s", r.description)
+
+	// Compute max width of name "column".
+	maxname := 0
+	for _, mem := range r.members {
+		if l := len(mem.obj.Name()); l > maxname {
+			maxname = l
+		}
+	}
+
+	for _, mem := range r.members {
+		printf(mem.obj, "\t%s", formatMember(mem.obj, maxname))
+		for _, meth := range mem.methods {
+			printf(meth.Obj(), "\t\t%s", types.SelectionString(meth, types.RelativeTo(r.pkg)))
+		}
+	}
+}
+
+func formatMember(obj types.Object, maxname int) string {
+	qualifier := types.RelativeTo(obj.Pkg())
+	var buf bytes.Buffer
+	fmt.Fprintf(&buf, "%-5s %-*s", tokenOf(obj), maxname, obj.Name())
+	switch obj := obj.(type) {
+	case *types.Const:
+		fmt.Fprintf(&buf, " %s = %s", types.TypeString(obj.Type(), qualifier), constValString(obj.Val()))
+
+	case *types.Func:
+		fmt.Fprintf(&buf, " %s", types.TypeString(obj.Type(), qualifier))
+
+	case *types.TypeName:
+		// Abbreviate long aggregate type names.
+		var abbrev string
+		switch t := obj.Type().Underlying().(type) {
+		case *types.Interface:
+			if t.NumMethods() > 1 {
+				abbrev = "interface{...}"
+			}
+		case *types.Struct:
+			if t.NumFields() > 1 {
+				abbrev = "struct{...}"
+			}
+		}
+		if abbrev == "" {
+			fmt.Fprintf(&buf, " %s", types.TypeString(obj.Type().Underlying(), qualifier))
+		} else {
+			fmt.Fprintf(&buf, " %s", abbrev)
+		}
+
+	case *types.Var:
+		fmt.Fprintf(&buf, " %s", types.TypeString(obj.Type(), qualifier))
+	}
+	return buf.String()
+}
+
+func (r *describePackageResult) toSerial(res *serial.Result, fset *token.FileSet) {
+	var members []*serial.DescribeMember
+	for _, mem := range r.members {
+		typ := mem.obj.Type()
+		var val string
+		switch mem := mem.obj.(type) {
+		case *types.Const:
+			val = constValString(mem.Val())
+		case *types.TypeName:
+			typ = typ.Underlying()
+		}
+		members = append(members, &serial.DescribeMember{
+			Name:    mem.obj.Name(),
+			Type:    typ.String(),
+			Value:   val,
+			Pos:     fset.Position(mem.obj.Pos()).String(),
+			Kind:    tokenOf(mem.obj),
+			Methods: methodsToSerial(r.pkg, mem.methods, fset),
+		})
+	}
+	res.Describe = &serial.Describe{
+		Desc:   r.description,
+		Pos:    fset.Position(r.node.Pos()).String(),
+		Detail: "package",
+		Package: &serial.DescribePackage{
+			Path:    r.pkg.Path(),
+			Members: members,
+		},
+	}
+}
+
+func tokenOf(o types.Object) string {
+	switch o.(type) {
+	case *types.Func:
+		return "func"
+	case *types.Var:
+		return "var"
+	case *types.TypeName:
+		return "type"
+	case *types.Const:
+		return "const"
+	case *types.PkgName:
+		return "package"
+	case *types.Builtin:
+		return "builtin" // e.g. when describing package "unsafe"
+	case *types.Nil:
+		return "nil"
+	case *types.Label:
+		return "label"
+	}
+	panic(o)
+}
+
+// ---- STATEMENT ------------------------------------------------------------
+
+func describeStmt(qpos *queryPos, path []ast.Node) (*describeStmtResult, error) {
+	var description string
+	switch n := path[0].(type) {
+	case *ast.Ident:
+		if qpos.info.Defs[n] != nil {
+			description = "labelled statement"
+		} else {
+			description = "reference to labelled statement"
+		}
+
+	default:
+		// Nothing much to say about statements.
+		description = astutil.NodeDescription(n)
+	}
+	return &describeStmtResult{qpos.fset, path[0], description}, nil
+}
+
+type describeStmtResult struct {
+	fset        *token.FileSet
+	node        ast.Node
+	description string
+}
+
+func (r *describeStmtResult) display(printf printfFunc) {
+	printf(r.node, "%s", r.description)
+}
+
+func (r *describeStmtResult) toSerial(res *serial.Result, fset *token.FileSet) {
+	res.Describe = &serial.Describe{
+		Desc:   r.description,
+		Pos:    fset.Position(r.node.Pos()).String(),
+		Detail: "unknown",
+	}
+}
+
+// ------------------- Utilities -------------------
+
+// pathToString returns a string containing the concrete types of the
+// nodes in path.
+func pathToString(path []ast.Node) string {
+	var buf bytes.Buffer
+	fmt.Fprint(&buf, "[")
+	for i, n := range path {
+		if i > 0 {
+			fmt.Fprint(&buf, " ")
+		}
+		fmt.Fprint(&buf, strings.TrimPrefix(fmt.Sprintf("%T", n), "*ast."))
+	}
+	fmt.Fprint(&buf, "]")
+	return buf.String()
+}
+
+func accessibleMethods(t types.Type, from *types.Package) []*types.Selection {
+	var methods []*types.Selection
+	for _, meth := range typeutil.IntuitiveMethodSet(t, nil) {
+		if isAccessibleFrom(meth.Obj(), from) {
+			methods = append(methods, meth)
+		}
+	}
+	return methods
+}
+
+func isAccessibleFrom(obj types.Object, pkg *types.Package) bool {
+	return ast.IsExported(obj.Name()) || obj.Pkg() == pkg
+}
+
+func methodsToSerial(this *types.Package, methods []*types.Selection, fset *token.FileSet) []serial.DescribeMethod {
+	qualifier := types.RelativeTo(this)
+	var jmethods []serial.DescribeMethod
+	for _, meth := range methods {
+		var ser serial.DescribeMethod
+		if meth != nil { // may contain nils when called by implements (on a method)
+			ser = serial.DescribeMethod{
+				Name: types.SelectionString(meth, qualifier),
+				Pos:  fset.Position(meth.Obj().Pos()).String(),
+			}
+		}
+		jmethods = append(jmethods, ser)
+	}
+	return jmethods
+}
+
+// constValString emulates Go 1.6's go/constant.ExactString well enough
+// to make the tests pass.  This is just a stopgap until we throw away
+// all the *15.go files.
+func constValString(v exact.Value) string {
+	if v.Kind() == exact.Float {
+		f, _ := exact.Float64Val(v)
+		return fmt.Sprintf("%g", f)
+	}
+	return v.String()
+}

vendor/github.com/visualfc/gotools/oracle/oracle/freevars.go

@@ -0,0 +1,224 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build go1.5
+
+package oracle
+
+import (
+	"bytes"
+	"go/ast"
+	"go/printer"
+	"go/token"
+	"go/types"
+	"sort"
+
+	"github.com/visualfc/gotools/oracle/oracle/serial"
+	"golang.org/x/tools/go/loader"
+)
+
+// freevars displays the lexical (not package-level) free variables of
+// the selection.
+//
+// It treats A.B.C as a separate variable from A to reveal the parts
+// of an aggregate type that are actually needed.
+// This aids refactoring.
+//
+// TODO(adonovan): optionally display the free references to
+// file/package scope objects, and to objects from other packages.
+// Depending on where the resulting function abstraction will go,
+// these might be interesting.  Perhaps group the results into three
+// bands.
+//
+func freevars(q *Query) error {
+	lconf := loader.Config{Build: q.Build}
+	allowErrors(&lconf)
+
+	if _, err := importQueryPackage(q.Pos, &lconf); err != nil {
+		return err
+	}
+
+	// Load/parse/type-check the program.
+	lprog, err := lconf.Load()
+	if err != nil {
+		return err
+	}
+	q.Fset = lprog.Fset
+
+	qpos, err := parseQueryPos(lprog, q.Pos, false)
+	if err != nil {
+		return err
+	}
+
+	file := qpos.path[len(qpos.path)-1] // the enclosing file
+	fileScope := qpos.info.Scopes[file]
+	pkgScope := fileScope.Parent()
+
+	// The id and sel functions return non-nil if they denote an
+	// object o or selection o.x.y that is referenced by the
+	// selection but defined neither within the selection nor at
+	// file scope, i.e. it is in the lexical environment.
+	var id func(n *ast.Ident) types.Object
+	var sel func(n *ast.SelectorExpr) types.Object
+
+	sel = func(n *ast.SelectorExpr) types.Object {
+		switch x := unparen(n.X).(type) {
+		case *ast.SelectorExpr:
+			return sel(x)
+		case *ast.Ident:
+			return id(x)
+		}
+		return nil
+	}
+
+	id = func(n *ast.Ident) types.Object {
+		obj := qpos.info.Uses[n]
+		if obj == nil {
+			return nil // not a reference
+		}
+		if _, ok := obj.(*types.PkgName); ok {
+			return nil // imported package
+		}
+		if !(file.Pos() <= obj.Pos() && obj.Pos() <= file.End()) {
+			return nil // not defined in this file
+		}
+		scope := obj.Parent()
+		if scope == nil {
+			return nil // e.g. interface method, struct field
+		}
+		if scope == fileScope || scope == pkgScope {
+			return nil // defined at file or package scope
+		}
+		if qpos.start <= obj.Pos() && obj.Pos() <= qpos.end {
+			return nil // defined within selection => not free
+		}
+		return obj
+	}
+
+	// Maps each reference that is free in the selection
+	// to the object it refers to.
+	// The map de-duplicates repeated references.
+	refsMap := make(map[string]freevarsRef)
+
+	// Visit all the identifiers in the selected ASTs.
+	ast.Inspect(qpos.path[0], func(n ast.Node) bool {
+		if n == nil {
+			return true // popping DFS stack
+		}
+
+		// Is this node contained within the selection?
+		// (freevars permits inexact selections,
+		// like two stmts in a block.)
+		if qpos.start <= n.Pos() && n.End() <= qpos.end {
+			var obj types.Object
+			var prune bool
+			switch n := n.(type) {
+			case *ast.Ident:
+				obj = id(n)
+
+			case *ast.SelectorExpr:
+				obj = sel(n)
+				prune = true
+			}
+
+			if obj != nil {
+				var kind string
+				switch obj.(type) {
+				case *types.Var:
+					kind = "var"
+				case *types.Func:
+					kind = "func"
+				case *types.TypeName:
+					kind = "type"
+				case *types.Const:
+					kind = "const"
+				case *types.Label:
+					kind = "label"
+				default:
+					panic(obj)
+				}
+
+				typ := qpos.info.TypeOf(n.(ast.Expr))
+				ref := freevarsRef{kind, printNode(lprog.Fset, n), typ, obj}
+				refsMap[ref.ref] = ref
+
+				if prune {
+					return false // don't descend
+				}
+			}
+		}
+
+		return true // descend
+	})
+
+	refs := make([]freevarsRef, 0, len(refsMap))
+	for _, ref := range refsMap {
+		refs = append(refs, ref)
+	}
+	sort.Sort(byRef(refs))
+
+	q.result = &freevarsResult{
+		qpos: qpos,
+		refs: refs,
+	}
+	return nil
+}
+
+type freevarsResult struct {
+	qpos *queryPos
+	refs []freevarsRef
+}
+
+type freevarsRef struct {
+	kind string
+	ref  string
+	typ  types.Type
+	obj  types.Object
+}
+
+func (r *freevarsResult) display(printf printfFunc) {
+	if len(r.refs) == 0 {
+		printf(r.qpos, "No free identifiers.")
+	} else {
+		printf(r.qpos, "Free identifiers:")
+		qualifier := types.RelativeTo(r.qpos.info.Pkg)
+		for _, ref := range r.refs {
+			// Avoid printing "type T T".
+			var typstr string
+			if ref.kind != "type" {
+				typstr = " " + types.TypeString(ref.typ, qualifier)
+			}
+			printf(ref.obj, "%s %s%s", ref.kind, ref.ref, typstr)
+		}
+	}
+}
+
+func (r *freevarsResult) toSerial(res *serial.Result, fset *token.FileSet) {
+	var refs []*serial.FreeVar
+	for _, ref := range r.refs {
+		refs = append(refs,
+			&serial.FreeVar{
+				Pos:  fset.Position(ref.obj.Pos()).String(),
+				Kind: ref.kind,
+				Ref:  ref.ref,
+				Type: ref.typ.String(),
+			})
+	}
+	res.Freevars = refs
+}
+
+// -------- utils --------
+
+type byRef []freevarsRef
+
+func (p byRef) Len() int           { return len(p) }
+func (p byRef) Less(i, j int) bool { return p[i].ref < p[j].ref }
+func (p byRef) Swap(i, j int)      { p[i], p[j] = p[j], p[i] }
+
+// printNode returns the pretty-printed syntax of n.
+func printNode(fset *token.FileSet, n ast.Node) string {
+	var buf bytes.Buffer
+	printer.Fprint(&buf, fset, n)
+	return buf.String()
+}

vendor/github.com/visualfc/gotools/oracle/oracle/implements.go

@@ -0,0 +1,354 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build go1.5
+
+package oracle
+
+import (
+	"fmt"
+	"go/ast"
+	"go/token"
+	"go/types"
+	"reflect"
+	"sort"
+	"strings"
+
+	"github.com/visualfc/gotools/oracle/oracle/serial"
+	"golang.org/x/tools/go/loader"
+	"golang.org/x/tools/go/types/typeutil"
+	"golang.org/x/tools/refactor/importgraph"
+)
+
+// Implements displays the "implements" relation as it pertains to the
+// selected type.
+// If the selection is a method, 'implements' displays
+// the corresponding methods of the types that would have been reported
+// by an implements query on the receiver type.
+//
+func implements(q *Query) error {
+	lconf := loader.Config{Build: q.Build}
+	allowErrors(&lconf)
+
+	qpkg, err := importQueryPackage(q.Pos, &lconf)
+	if err != nil {
+		return err
+	}
+
+	// Set the packages to search.
+	if len(q.Scope) > 0 {
+		// Inspect all packages in the analysis scope, if specified.
+		if err := setPTAScope(&lconf, q.Scope); err != nil {
+			return err
+		}
+	} else {
+		// Otherwise inspect the forward and reverse
+		// transitive closure of the selected package.
+		// (In theory even this is incomplete.)
+		_, rev, _ := importgraph.Build(q.Build)
+		for path := range rev.Search(qpkg) {
+			lconf.ImportWithTests(path)
+		}
+
+		// TODO(adonovan): for completeness, we should also
+		// type-check and inspect function bodies in all
+		// imported packages.  This would be expensive, but we
+		// could optimize by skipping functions that do not
+		// contain type declarations.  This would require
+		// changing the loader's TypeCheckFuncBodies hook to
+		// provide the []*ast.File.
+	}
+
+	// Load/parse/type-check the program.
+	lprog, err := lconf.Load()
+	if err != nil {
+		return err
+	}
+	q.Fset = lprog.Fset
+
+	qpos, err := parseQueryPos(lprog, q.Pos, false)
+	if err != nil {
+		return err
+	}
+
+	// Find the selected type.
+	path, action := findInterestingNode(qpos.info, qpos.path)
+
+	var method *types.Func
+	var T types.Type // selected type (receiver if method != nil)
+
+	switch action {
+	case actionExpr:
+		// method?
+		if id, ok := path[0].(*ast.Ident); ok {
+			if obj, ok := qpos.info.ObjectOf(id).(*types.Func); ok {
+				recv := obj.Type().(*types.Signature).Recv()
+				if recv == nil {
+					return fmt.Errorf("this function is not a method")
+				}
+				method = obj
+				T = recv.Type()
+			}
+		}
+	case actionType:
+		T = qpos.info.TypeOf(path[0].(ast.Expr))
+	}
+	if T == nil {
+		return fmt.Errorf("no type or method here")
+	}
+
+	// Find all named types, even local types (which can have
+	// methods via promotion) and the built-in "error".
+	var allNamed []types.Type
+	for _, info := range lprog.AllPackages {
+		for _, obj := range info.Defs {
+			if obj, ok := obj.(*types.TypeName); ok {
+				allNamed = append(allNamed, obj.Type())
+			}
+		}
+	}
+	allNamed = append(allNamed, types.Universe.Lookup("error").Type())
+
+	var msets typeutil.MethodSetCache
+
+	// Test each named type.
+	var to, from, fromPtr []types.Type
+	for _, U := range allNamed {
+		if isInterface(T) {
+			if msets.MethodSet(T).Len() == 0 {
+				continue // empty interface
+			}
+			if isInterface(U) {
+				if msets.MethodSet(U).Len() == 0 {
+					continue // empty interface
+				}
+
+				// T interface, U interface
+				if !types.Identical(T, U) {
+					if types.AssignableTo(U, T) {
+						to = append(to, U)
+					}
+					if types.AssignableTo(T, U) {
+						from = append(from, U)
+					}
+				}
+			} else {
+				// T interface, U concrete
+				if types.AssignableTo(U, T) {
+					to = append(to, U)
+				} else if pU := types.NewPointer(U); types.AssignableTo(pU, T) {
+					to = append(to, pU)
+				}
+			}
+		} else if isInterface(U) {
+			if msets.MethodSet(U).Len() == 0 {
+				continue // empty interface
+			}
+
+			// T concrete, U interface
+			if types.AssignableTo(T, U) {
+				from = append(from, U)
+			} else if pT := types.NewPointer(T); types.AssignableTo(pT, U) {
+				fromPtr = append(fromPtr, U)
+			}
+		}
+	}
+
+	var pos interface{} = qpos
+	if nt, ok := deref(T).(*types.Named); ok {
+		pos = nt.Obj()
+	}
+
+	// Sort types (arbitrarily) to ensure test determinism.
+	sort.Sort(typesByString(to))
+	sort.Sort(typesByString(from))
+	sort.Sort(typesByString(fromPtr))
+
+	var toMethod, fromMethod, fromPtrMethod []*types.Selection // contain nils
+	if method != nil {
+		for _, t := range to {
+			toMethod = append(toMethod,
+				types.NewMethodSet(t).Lookup(method.Pkg(), method.Name()))
+		}
+		for _, t := range from {
+			fromMethod = append(fromMethod,
+				types.NewMethodSet(t).Lookup(method.Pkg(), method.Name()))
+		}
+		for _, t := range fromPtr {
+			fromPtrMethod = append(fromPtrMethod,
+				types.NewMethodSet(t).Lookup(method.Pkg(), method.Name()))
+		}
+	}
+
+	q.result = &implementsResult{
+		qpos, T, pos, to, from, fromPtr, method, toMethod, fromMethod, fromPtrMethod,
+	}
+	return nil
+}
+
+type implementsResult struct {
+	qpos *queryPos
+
+	t       types.Type   // queried type (not necessarily named)
+	pos     interface{}  // pos of t (*types.Name or *QueryPos)
+	to      []types.Type // named or ptr-to-named types assignable to interface T
+	from    []types.Type // named interfaces assignable from T
+	fromPtr []types.Type // named interfaces assignable only from *T
+
+	// if a method was queried:
+	method        *types.Func        // queried method
+	toMethod      []*types.Selection // method of type to[i], if any
+	fromMethod    []*types.Selection // method of type from[i], if any
+	fromPtrMethod []*types.Selection // method of type fromPtrMethod[i], if any
+}
+
+func (r *implementsResult) display(printf printfFunc) {
+	relation := "is implemented by"
+
+	meth := func(sel *types.Selection) {
+		if sel != nil {
+			printf(sel.Obj(), "\t%s method (%s).%s",
+				relation, r.qpos.typeString(sel.Recv()), sel.Obj().Name())
+		}
+	}
+
+	if isInterface(r.t) {
+		if types.NewMethodSet(r.t).Len() == 0 { // TODO(adonovan): cache mset
+			printf(r.pos, "empty interface type %s", r.qpos.typeString(r.t))
+			return
+		}
+
+		if r.method == nil {
+			printf(r.pos, "interface type %s", r.qpos.typeString(r.t))
+		} else {
+			printf(r.method, "abstract method %s", r.qpos.objectString(r.method))
+		}
+
+		// Show concrete types (or methods) first; use two passes.
+		for i, sub := range r.to {
+			if !isInterface(sub) {
+				if r.method == nil {
+					printf(deref(sub).(*types.Named).Obj(), "\t%s %s type %s",
+						relation, typeKind(sub), r.qpos.typeString(sub))
+				} else {
+					meth(r.toMethod[i])
+				}
+			}
+		}
+		for i, sub := range r.to {
+			if isInterface(sub) {
+				if r.method == nil {
+					printf(sub.(*types.Named).Obj(), "\t%s %s type %s",
+						relation, typeKind(sub), r.qpos.typeString(sub))
+				} else {
+					meth(r.toMethod[i])
+				}
+			}
+		}
+
+		relation = "implements"
+		for i, super := range r.from {
+			if r.method == nil {
+				printf(super.(*types.Named).Obj(), "\t%s %s",
+					relation, r.qpos.typeString(super))
+			} else {
+				meth(r.fromMethod[i])
+			}
+		}
+	} else {
+		relation = "implements"
+
+		if r.from != nil {
+			if r.method == nil {
+				printf(r.pos, "%s type %s",
+					typeKind(r.t), r.qpos.typeString(r.t))
+			} else {
+				printf(r.method, "concrete method %s",
+					r.qpos.objectString(r.method))
+			}
+			for i, super := range r.from {
+				if r.method == nil {
+					printf(super.(*types.Named).Obj(), "\t%s %s",
+						relation, r.qpos.typeString(super))
+				} else {
+					meth(r.fromMethod[i])
+				}
+			}
+		}
+		if r.fromPtr != nil {
+			if r.method == nil {
+				printf(r.pos, "pointer type *%s", r.qpos.typeString(r.t))
+			} else {
+				// TODO(adonovan): de-dup (C).f and (*C).f implementing (I).f.
+				printf(r.method, "concrete method %s",
+					r.qpos.objectString(r.method))
+			}
+
+			for i, psuper := range r.fromPtr {
+				if r.method == nil {
+					printf(psuper.(*types.Named).Obj(), "\t%s %s",
+						relation, r.qpos.typeString(psuper))
+				} else {
+					meth(r.fromPtrMethod[i])
+				}
+			}
+		} else if r.from == nil {
+			printf(r.pos, "%s type %s implements only interface{}",
+				typeKind(r.t), r.qpos.typeString(r.t))
+		}
+	}
+}
+
+func (r *implementsResult) toSerial(res *serial.Result, fset *token.FileSet) {
+	res.Implements = &serial.Implements{
+		T:                       makeImplementsType(r.t, fset),
+		AssignableTo:            makeImplementsTypes(r.to, fset),
+		AssignableFrom:          makeImplementsTypes(r.from, fset),
+		AssignableFromPtr:       makeImplementsTypes(r.fromPtr, fset),
+		AssignableToMethod:      methodsToSerial(r.qpos.info.Pkg, r.toMethod, fset),
+		AssignableFromMethod:    methodsToSerial(r.qpos.info.Pkg, r.fromMethod, fset),
+		AssignableFromPtrMethod: methodsToSerial(r.qpos.info.Pkg, r.fromPtrMethod, fset),
+	}
+	if r.method != nil {
+		res.Implements.Method = &serial.DescribeMethod{
+			Name: r.qpos.objectString(r.method),
+			Pos:  fset.Position(r.method.Pos()).String(),
+		}
+	}
+}
+
+func makeImplementsTypes(tt []types.Type, fset *token.FileSet) []serial.ImplementsType {
+	var r []serial.ImplementsType
+	for _, t := range tt {
+		r = append(r, makeImplementsType(t, fset))
+	}
+	return r
+}
+
+func makeImplementsType(T types.Type, fset *token.FileSet) serial.ImplementsType {
+	var pos token.Pos
+	if nt, ok := deref(T).(*types.Named); ok { // implementsResult.t may be non-named
+		pos = nt.Obj().Pos()
+	}
+	return serial.ImplementsType{
+		Name: T.String(),
+		Pos:  fset.Position(pos).String(),
+		Kind: typeKind(T),
+	}
+}
+
+// typeKind returns a string describing the underlying kind of type,
+// e.g. "slice", "array", "struct".
+func typeKind(T types.Type) string {
+	s := reflect.TypeOf(T.Underlying()).String()
+	return strings.ToLower(strings.TrimPrefix(s, "*types."))
+}
+
+func isInterface(T types.Type) bool { return types.IsInterface(T) }
+
+type typesByString []types.Type
+
+func (p typesByString) Len() int           { return len(p) }
+func (p typesByString) Less(i, j int) bool { return p[i].String() < p[j].String() }
+func (p typesByString) Swap(i, j int)      { p[i], p[j] = p[j], p[i] }

vendor/github.com/visualfc/gotools/oracle/oracle/oracle.go

@@ -0,0 +1,381 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build go1.5
+
+// Package oracle contains the implementation of the oracle tool whose
+// command-line is provided by golang.org/x/tools/cmd/oracle.
+//
+// http://golang.org/s/oracle-design
+// http://golang.org/s/oracle-user-manual
+//
+package oracle
+
+// This file defines oracle.Query, the entry point for the oracle tool.
+// The actual executable is defined in cmd/oracle.
+
+// TODO(adonovan): new queries
+// - show all statements that may update the selected lvalue
+//   (local, global, field, etc).
+// - show all places where an object of type T is created
+//   (&T{}, var t T, new(T), new(struct{array [3]T}), etc.
+
+import (
+	"fmt"
+	"go/ast"
+	"go/build"
+	"go/parser"
+	"go/token"
+	"go/types"
+	"io"
+	"path/filepath"
+
+	"github.com/visualfc/gotools/oracle/oracle/serial"
+	"golang.org/x/tools/go/ast/astutil"
+	"golang.org/x/tools/go/buildutil"
+	"golang.org/x/tools/go/loader"
+	"golang.org/x/tools/go/pointer"
+	"golang.org/x/tools/go/ssa"
+)
+
+type printfFunc func(pos interface{}, format string, args ...interface{})
+
+// queryResult is the interface of each query-specific result type.
+type queryResult interface {
+	toSerial(res *serial.Result, fset *token.FileSet)
+	display(printf printfFunc)
+}
+
+// A QueryPos represents the position provided as input to a query:
+// a textual extent in the program's source code, the AST node it
+// corresponds to, and the package to which it belongs.
+// Instances are created by parseQueryPos.
+type queryPos struct {
+	fset       *token.FileSet
+	start, end token.Pos           // source extent of query
+	path       []ast.Node          // AST path from query node to root of ast.File
+	exact      bool                // 2nd result of PathEnclosingInterval
+	info       *loader.PackageInfo // type info for the queried package (nil for fastQueryPos)
+}
+
+// TypeString prints type T relative to the query position.
+func (qpos *queryPos) typeString(T types.Type) string {
+	return types.TypeString(T, types.RelativeTo(qpos.info.Pkg))
+}
+
+// ObjectString prints object obj relative to the query position.
+func (qpos *queryPos) objectString(obj types.Object) string {
+	return types.ObjectString(obj, types.RelativeTo(qpos.info.Pkg))
+}
+
+// SelectionString prints selection sel relative to the query position.
+func (qpos *queryPos) selectionString(sel *types.Selection) string {
+	return types.SelectionString(sel, types.RelativeTo(qpos.info.Pkg))
+}
+
+// A Query specifies a single oracle query.
+type Query struct {
+	Mode  string         // query mode ("callers", etc)
+	Pos   string         // query position
+	Build *build.Context // package loading configuration
+
+	// pointer analysis options
+	Scope      []string  // main packages in (*loader.Config).FromArgs syntax
+	PTALog     io.Writer // (optional) pointer-analysis log file
+	Reflection bool      // model reflection soundly (currently slow).
+
+	// Populated during Run()
+	Fset   *token.FileSet
+	result queryResult
+}
+
+// Serial returns an instance of serial.Result, which implements the
+// {xml,json}.Marshaler interfaces so that query results can be
+// serialized as JSON or XML.
+//
+func (q *Query) Serial() *serial.Result {
+	resj := &serial.Result{Mode: q.Mode}
+	q.result.toSerial(resj, q.Fset)
+	return resj
+}
+
+// WriteTo writes the oracle query result res to out in a compiler diagnostic format.
+func (q *Query) WriteTo(out io.Writer) {
+	printf := func(pos interface{}, format string, args ...interface{}) {
+		fprintf(out, q.Fset, pos, format, args...)
+	}
+	q.result.display(printf)
+}
+
+// Run runs an oracle query and populates its Fset and Result.
+func Run(q *Query) error {
+	switch q.Mode {
+	case "callees":
+		return callees(q)
+	case "callers":
+		return callers(q)
+	case "callstack":
+		return callstack(q)
+	case "peers":
+		return peers(q)
+	case "pointsto":
+		return pointsto(q)
+	case "whicherrs":
+		return whicherrs(q)
+	case "definition":
+		return definition(q)
+	case "describe":
+		return describe(q)
+	case "freevars":
+		return freevars(q)
+	case "implements":
+		return implements(q)
+	case "referrers":
+		return referrers(q)
+	case "what":
+		return what(q)
+	default:
+		return fmt.Errorf("invalid mode: %q", q.Mode)
+	}
+}
+
+func setPTAScope(lconf *loader.Config, scope []string) error {
+	pkgs := buildutil.ExpandPatterns(lconf.Build, scope)
+	if len(pkgs) == 0 {
+		return fmt.Errorf("no packages specified for pointer analysis scope")
+	}
+	// The value of each entry in pkgs is true,
+	// giving ImportWithTests (not Import) semantics.
+	lconf.ImportPkgs = pkgs
+	return nil
+}
+
+//func setPTAScope(lconf *loader.Config, scope []string) error {
+//	if len(scope) == 0 {
+//		return fmt.Errorf("no packages specified for pointer analysis scope")
+//	}
+
+//	// Determine initial packages for PTA.
+//	args, err := lconf.FromArgs(scope, true)
+//	if err != nil {
+//		return err
+//	}
+//	if len(args) > 0 {
+//		return fmt.Errorf("surplus arguments: %q", args)
+//	}
+//	return nil
+//}
+
+// Create a pointer.Config whose scope is the initial packages of lprog
+// and their dependencies.
+func setupPTA(prog *ssa.Program, lprog *loader.Program, ptaLog io.Writer, reflection bool) (*pointer.Config, error) {
+	// TODO(adonovan): the body of this function is essentially
+	// duplicated in all go/pointer clients.  Refactor.
+
+	// For each initial package (specified on the command line),
+	// if it has a main function, analyze that,
+	// otherwise analyze its tests, if any.
+	var testPkgs, mains []*ssa.Package
+	for _, info := range lprog.InitialPackages() {
+		initialPkg := prog.Package(info.Pkg)
+
+		// Add package to the pointer analysis scope.
+		if initialPkg.Func("main") != nil {
+			mains = append(mains, initialPkg)
+		} else {
+			testPkgs = append(testPkgs, initialPkg)
+		}
+	}
+	if testPkgs != nil {
+		for _, testPkg := range testPkgs {
+			if p := prog.CreateTestMainPackage(testPkg); p != nil {
+				mains = append(mains, p)
+			}
+		}
+	}
+	if mains == nil {
+		return nil, fmt.Errorf("analysis scope has no main and no tests")
+	}
+	return &pointer.Config{
+		Log:        ptaLog,
+		Reflection: reflection,
+		Mains:      mains,
+	}, nil
+}
+
+// importQueryPackage finds the package P containing the
+// query position and tells conf to import it.
+// It returns the package's path.
+func importQueryPackage(pos string, conf *loader.Config) (string, error) {
+	fqpos, err := fastQueryPos(pos)
+	if err != nil {
+		return "", err // bad query
+	}
+	filename := fqpos.fset.File(fqpos.start).Name()
+
+	// This will not work for ad-hoc packages
+	// such as $GOROOT/src/net/http/triv.go.
+	// TODO(adonovan): ensure we report a clear error.
+	_, importPath, err := guessImportPath(filename, conf.Build)
+	if err != nil {
+		return "", err // can't find GOPATH dir
+	}
+	if importPath == "" {
+		return "", fmt.Errorf("can't guess import path from %s", filename)
+	}
+
+	// Check that it's possible to load the queried package.
+	// (e.g. oracle tests contain different 'package' decls in same dir.)
+	// Keep consistent with logic in loader/util.go!
+	cfg2 := *conf.Build
+	cfg2.CgoEnabled = false
+	bp, err := cfg2.Import(importPath, "", 0)
+	if err != nil {
+		return "", err // no files for package
+	}
+
+	switch pkgContainsFile(bp, filename) {
+	case 'T':
+		conf.ImportWithTests(importPath)
+	case 'X':
+		conf.ImportWithTests(importPath)
+		importPath += "_test" // for TypeCheckFuncBodies
+	case 'G':
+		conf.Import(importPath)
+	default:
+		return "", fmt.Errorf("package %q doesn't contain file %s",
+			importPath, filename)
+	}
+
+	conf.TypeCheckFuncBodies = func(p string) bool { return p == importPath }
+
+	return importPath, nil
+}
+
+// pkgContainsFile reports whether file was among the packages Go
+// files, Test files, eXternal test files, or not found.
+func pkgContainsFile(bp *build.Package, filename string) byte {
+	for i, files := range [][]string{bp.GoFiles, bp.TestGoFiles, bp.XTestGoFiles} {
+		for _, file := range files {
+			if sameFile(filepath.Join(bp.Dir, file), filename) {
+				return "GTX"[i]
+			}
+		}
+	}
+	return 0 // not found
+}
+
+// ParseQueryPos parses the source query position pos and returns the
+// AST node of the loaded program lprog that it identifies.
+// If needExact, it must identify a single AST subtree;
+// this is appropriate for queries that allow fairly arbitrary syntax,
+// e.g. "describe".
+//
+func parseQueryPos(lprog *loader.Program, posFlag string, needExact bool) (*queryPos, error) {
+	filename, startOffset, endOffset, err := parsePosFlag(posFlag)
+	if err != nil {
+		return nil, err
+	}
+	start, end, err := findQueryPos(lprog.Fset, filename, startOffset, endOffset)
+	if err != nil {
+		return nil, err
+	}
+	info, path, exact := lprog.PathEnclosingInterval(start, end)
+	if path == nil {
+		return nil, fmt.Errorf("no syntax here")
+	}
+	if needExact && !exact {
+		return nil, fmt.Errorf("ambiguous selection within %s", astutil.NodeDescription(path[0]))
+	}
+	return &queryPos{lprog.Fset, start, end, path, exact, info}, nil
+}
+
+// ---------- Utilities ----------
+
+// allowErrors causes type errors to be silently ignored.
+// (Not suitable if SSA construction follows.)
+func allowErrors(lconf *loader.Config) {
+	ctxt := *lconf.Build // copy
+	ctxt.CgoEnabled = false
+	lconf.Build = &ctxt
+	lconf.AllowErrors = true
+	// AllErrors makes the parser always return an AST instead of
+	// bailing out after 10 errors and returning an empty ast.File.
+	lconf.ParserMode = parser.AllErrors
+	lconf.TypeChecker.Error = func(err error) {}
+}
+
+// ptrAnalysis runs the pointer analysis and returns its result.
+func ptrAnalysis(conf *pointer.Config) *pointer.Result {
+	result, err := pointer.Analyze(conf)
+	if err != nil {
+		panic(err) // pointer analysis internal error
+	}
+	return result
+}
+
+func unparen(e ast.Expr) ast.Expr { return astutil.Unparen(e) }
+
+// deref returns a pointer's element type; otherwise it returns typ.
+func deref(typ types.Type) types.Type {
+	if p, ok := typ.Underlying().(*types.Pointer); ok {
+		return p.Elem()
+	}
+	return typ
+}
+
+// fprintf prints to w a message of the form "location: message\n"
+// where location is derived from pos.
+//
+// pos must be one of:
+//    - a token.Pos, denoting a position
+//    - an ast.Node, denoting an interval
+//    - anything with a Pos() method:
+//         ssa.Member, ssa.Value, ssa.Instruction, types.Object, pointer.Label, etc.
+//    - a QueryPos, denoting the extent of the user's query.
+//    - nil, meaning no position at all.
+//
+// The output format is is compatible with the 'gnu'
+// compilation-error-regexp in Emacs' compilation mode.
+// TODO(adonovan): support other editors.
+//
+func fprintf(w io.Writer, fset *token.FileSet, pos interface{}, format string, args ...interface{}) {
+	var start, end token.Pos
+	switch pos := pos.(type) {
+	case ast.Node:
+		start = pos.Pos()
+		end = pos.End()
+	case token.Pos:
+		start = pos
+		end = start
+	case interface {
+		Pos() token.Pos
+	}:
+		start = pos.Pos()
+		end = start
+	case *queryPos:
+		start = pos.start
+		end = pos.end
+	case nil:
+		// no-op
+	default:
+		panic(fmt.Sprintf("invalid pos: %T", pos))
+	}
+
+	if sp := fset.Position(start); start == end {
+		// (prints "-: " for token.NoPos)
+		fmt.Fprintf(w, "%s: ", sp)
+	} else {
+		ep := fset.Position(end)
+		// The -1 below is a concession to Emacs's broken use of
+		// inclusive (not half-open) intervals.
+		// Other editors may not want it.
+		// TODO(adonovan): add an -editor=vim|emacs|acme|auto
+		// flag; auto uses EMACS=t / VIM=... / etc env vars.
+		fmt.Fprintf(w, "%s:%d.%d-%d.%d: ",
+			sp.Filename, sp.Line, sp.Column, ep.Line, ep.Column-1)
+	}
+	fmt.Fprintf(w, format, args...)
+	io.WriteString(w, "\n")
+}

vendor/github.com/visualfc/gotools/oracle/oracle/peers.go

@@ -0,0 +1,254 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build go1.5
+
+package oracle
+
+import (
+	"fmt"
+	"go/ast"
+	"go/token"
+	"go/types"
+	"sort"
+
+	"github.com/visualfc/gotools/oracle/oracle/serial"
+	"golang.org/x/tools/go/loader"
+	"golang.org/x/tools/go/ssa"
+	"golang.org/x/tools/go/ssa/ssautil"
+)
+
+// peers enumerates, for a given channel send (or receive) operation,
+// the set of possible receives (or sends) that correspond to it.
+//
+// TODO(adonovan): support reflect.{Select,Recv,Send,Close}.
+// TODO(adonovan): permit the user to query based on a MakeChan (not send/recv),
+// or the implicit receive in "for v := range ch".
+func peers(q *Query) error {
+	lconf := loader.Config{Build: q.Build}
+
+	if err := setPTAScope(&lconf, q.Scope); err != nil {
+		return err
+	}
+
+	// Load/parse/type-check the program.
+	lprog, err := lconf.Load()
+	if err != nil {
+		return err
+	}
+	q.Fset = lprog.Fset
+
+	qpos, err := parseQueryPos(lprog, q.Pos, false)
+	if err != nil {
+		return err
+	}
+
+	prog := ssautil.CreateProgram(lprog, ssa.GlobalDebug)
+
+	ptaConfig, err := setupPTA(prog, lprog, q.PTALog, q.Reflection)
+	if err != nil {
+		return err
+	}
+
+	opPos := findOp(qpos)
+	if opPos == token.NoPos {
+		return fmt.Errorf("there is no channel operation here")
+	}
+
+	// Defer SSA construction till after errors are reported.
+	prog.Build()
+
+	var queryOp chanOp // the originating send or receive operation
+	var ops []chanOp   // all sends/receives of opposite direction
+
+	// Look at all channel operations in the whole ssa.Program.
+	// Build a list of those of same type as the query.
+	allFuncs := ssautil.AllFunctions(prog)
+	for fn := range allFuncs {
+		for _, b := range fn.Blocks {
+			for _, instr := range b.Instrs {
+				for _, op := range chanOps(instr) {
+					ops = append(ops, op)
+					if op.pos == opPos {
+						queryOp = op // we found the query op
+					}
+				}
+			}
+		}
+	}
+	if queryOp.ch == nil {
+		return fmt.Errorf("ssa.Instruction for send/receive not found")
+	}
+
+	// Discard operations of wrong channel element type.
+	// Build set of channel ssa.Values as query to pointer analysis.
+	// We compare channels by element types, not channel types, to
+	// ignore both directionality and type names.
+	queryType := queryOp.ch.Type()
+	queryElemType := queryType.Underlying().(*types.Chan).Elem()
+	ptaConfig.AddQuery(queryOp.ch)
+	i := 0
+	for _, op := range ops {
+		if types.Identical(op.ch.Type().Underlying().(*types.Chan).Elem(), queryElemType) {
+			ptaConfig.AddQuery(op.ch)
+			ops[i] = op
+			i++
+		}
+	}
+	ops = ops[:i]
+
+	// Run the pointer analysis.
+	ptares := ptrAnalysis(ptaConfig)
+
+	// Find the points-to set.
+	queryChanPtr := ptares.Queries[queryOp.ch]
+
+	// Ascertain which make(chan) labels the query's channel can alias.
+	var makes []token.Pos
+	for _, label := range queryChanPtr.PointsTo().Labels() {
+		makes = append(makes, label.Pos())
+	}
+	sort.Sort(byPos(makes))
+
+	// Ascertain which channel operations can alias the same make(chan) labels.
+	var sends, receives, closes []token.Pos
+	for _, op := range ops {
+		if ptr, ok := ptares.Queries[op.ch]; ok && ptr.MayAlias(queryChanPtr) {
+			switch op.dir {
+			case types.SendOnly:
+				sends = append(sends, op.pos)
+			case types.RecvOnly:
+				receives = append(receives, op.pos)
+			case types.SendRecv:
+				closes = append(closes, op.pos)
+			}
+		}
+	}
+	sort.Sort(byPos(sends))
+	sort.Sort(byPos(receives))
+	sort.Sort(byPos(closes))
+
+	q.result = &peersResult{
+		queryPos:  opPos,
+		queryType: queryType,
+		makes:     makes,
+		sends:     sends,
+		receives:  receives,
+		closes:    closes,
+	}
+	return nil
+}
+
+// findOp returns the position of the enclosing send/receive/close op.
+// For send and receive operations, this is the position of the <- token;
+// for close operations, it's the Lparen of the function call.
+//
+// TODO(adonovan): handle implicit receive operations from 'for...range chan' statements.
+func findOp(qpos *queryPos) token.Pos {
+	for _, n := range qpos.path {
+		switch n := n.(type) {
+		case *ast.UnaryExpr:
+			if n.Op == token.ARROW {
+				return n.OpPos
+			}
+		case *ast.SendStmt:
+			return n.Arrow
+		case *ast.CallExpr:
+			// close function call can only exist as a direct identifier
+			if close, ok := unparen(n.Fun).(*ast.Ident); ok {
+				if b, ok := qpos.info.Info.Uses[close].(*types.Builtin); ok && b.Name() == "close" {
+					return n.Lparen
+				}
+			}
+		}
+	}
+	return token.NoPos
+}
+
+// chanOp abstracts an ssa.Send, ssa.Unop(ARROW), or a SelectState.
+type chanOp struct {
+	ch  ssa.Value
+	dir types.ChanDir // SendOnly=send, RecvOnly=recv, SendRecv=close
+	pos token.Pos
+}
+
+// chanOps returns a slice of all the channel operations in the instruction.
+func chanOps(instr ssa.Instruction) []chanOp {
+	// TODO(adonovan): handle calls to reflect.{Select,Recv,Send,Close} too.
+	var ops []chanOp
+	switch instr := instr.(type) {
+	case *ssa.UnOp:
+		if instr.Op == token.ARROW {
+			ops = append(ops, chanOp{instr.X, types.RecvOnly, instr.Pos()})
+		}
+	case *ssa.Send:
+		ops = append(ops, chanOp{instr.Chan, types.SendOnly, instr.Pos()})
+	case *ssa.Select:
+		for _, st := range instr.States {
+			ops = append(ops, chanOp{st.Chan, st.Dir, st.Pos})
+		}
+	case ssa.CallInstruction:
+		cc := instr.Common()
+		if b, ok := cc.Value.(*ssa.Builtin); ok && b.Name() == "close" {
+			ops = append(ops, chanOp{cc.Args[0], types.SendRecv, cc.Pos()})
+		}
+	}
+	return ops
+}
+
+type peersResult struct {
+	queryPos                       token.Pos   // of queried channel op
+	queryType                      types.Type  // type of queried channel
+	makes, sends, receives, closes []token.Pos // positions of aliased makechan/send/receive/close instrs
+}
+
+func (r *peersResult) display(printf printfFunc) {
+	if len(r.makes) == 0 {
+		printf(r.queryPos, "This channel can't point to anything.")
+		return
+	}
+	printf(r.queryPos, "This channel of type %s may be:", r.queryType)
+	for _, alloc := range r.makes {
+		printf(alloc, "\tallocated here")
+	}
+	for _, send := range r.sends {
+		printf(send, "\tsent to, here")
+	}
+	for _, receive := range r.receives {
+		printf(receive, "\treceived from, here")
+	}
+	for _, clos := range r.closes {
+		printf(clos, "\tclosed, here")
+	}
+}
+
+func (r *peersResult) toSerial(res *serial.Result, fset *token.FileSet) {
+	peers := &serial.Peers{
+		Pos:  fset.Position(r.queryPos).String(),
+		Type: r.queryType.String(),
+	}
+	for _, alloc := range r.makes {
+		peers.Allocs = append(peers.Allocs, fset.Position(alloc).String())
+	}
+	for _, send := range r.sends {
+		peers.Sends = append(peers.Sends, fset.Position(send).String())
+	}
+	for _, receive := range r.receives {
+		peers.Receives = append(peers.Receives, fset.Position(receive).String())
+	}
+	for _, clos := range r.closes {
+		peers.Closes = append(peers.Closes, fset.Position(clos).String())
+	}
+	res.Peers = peers
+}
+
+// -------- utils --------
+
+// NB: byPos is not deterministic across packages since it depends on load order.
+// Use lessPos if the tests need it.
+type byPos []token.Pos
+
+func (p byPos) Len() int           { return len(p) }
+func (p byPos) Less(i, j int) bool { return p[i] < p[j] }
+func (p byPos) Swap(i, j int)      { p[i], p[j] = p[j], p[i] }

vendor/github.com/visualfc/gotools/oracle/oracle/pointsto.go

@@ -0,0 +1,293 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build go1.5
+
+package oracle
+
+import (
+	"fmt"
+	"go/ast"
+	"go/token"
+	"go/types"
+	"sort"
+
+	"github.com/visualfc/gotools/oracle/oracle/serial"
+	"golang.org/x/tools/go/ast/astutil"
+	"golang.org/x/tools/go/loader"
+	"golang.org/x/tools/go/pointer"
+	"golang.org/x/tools/go/ssa"
+	"golang.org/x/tools/go/ssa/ssautil"
+)
+
+// pointsto runs the pointer analysis on the selected expression,
+// and reports its points-to set (for a pointer-like expression)
+// or its dynamic types (for an interface, reflect.Value, or
+// reflect.Type expression) and their points-to sets.
+//
+// All printed sets are sorted to ensure determinism.
+//
+func pointsto(q *Query) error {
+	lconf := loader.Config{Build: q.Build}
+
+	if err := setPTAScope(&lconf, q.Scope); err != nil {
+		return err
+	}
+
+	// Load/parse/type-check the program.
+	lprog, err := lconf.Load()
+	if err != nil {
+		return err
+	}
+	q.Fset = lprog.Fset
+
+	qpos, err := parseQueryPos(lprog, q.Pos, true) // needs exact pos
+	if err != nil {
+		return err
+	}
+
+	prog := ssautil.CreateProgram(lprog, ssa.GlobalDebug)
+
+	ptaConfig, err := setupPTA(prog, lprog, q.PTALog, q.Reflection)
+	if err != nil {
+		return err
+	}
+
+	path, action := findInterestingNode(qpos.info, qpos.path)
+	if action != actionExpr {
+		return fmt.Errorf("pointer analysis wants an expression; got %s",
+			astutil.NodeDescription(qpos.path[0]))
+	}
+
+	var expr ast.Expr
+	var obj types.Object
+	switch n := path[0].(type) {
+	case *ast.ValueSpec:
+		// ambiguous ValueSpec containing multiple names
+		return fmt.Errorf("multiple value specification")
+	case *ast.Ident:
+		obj = qpos.info.ObjectOf(n)
+		expr = n
+	case ast.Expr:
+		expr = n
+	default:
+		// TODO(adonovan): is this reachable?
+		return fmt.Errorf("unexpected AST for expr: %T", n)
+	}
+
+	// Reject non-pointerlike types (includes all constants---except nil).
+	// TODO(adonovan): reject nil too.
+	typ := qpos.info.TypeOf(expr)
+	if !pointer.CanPoint(typ) {
+		return fmt.Errorf("pointer analysis wants an expression of reference type; got %s", typ)
+	}
+
+	// Determine the ssa.Value for the expression.
+	var value ssa.Value
+	var isAddr bool
+	if obj != nil {
+		// def/ref of func/var object
+		value, isAddr, err = ssaValueForIdent(prog, qpos.info, obj, path)
+	} else {
+		value, isAddr, err = ssaValueForExpr(prog, qpos.info, path)
+	}
+	if err != nil {
+		return err // e.g. trivially dead code
+	}
+
+	// Defer SSA construction till after errors are reported.
+	prog.Build()
+
+	// Run the pointer analysis.
+	ptrs, err := runPTA(ptaConfig, value, isAddr)
+	if err != nil {
+		return err // e.g. analytically unreachable
+	}
+
+	q.result = &pointstoResult{
+		qpos: qpos,
+		typ:  typ,
+		ptrs: ptrs,
+	}
+	return nil
+}
+
+// ssaValueForIdent returns the ssa.Value for the ast.Ident whose path
+// to the root of the AST is path.  isAddr reports whether the
+// ssa.Value is the address denoted by the ast.Ident, not its value.
+//
+func ssaValueForIdent(prog *ssa.Program, qinfo *loader.PackageInfo, obj types.Object, path []ast.Node) (value ssa.Value, isAddr bool, err error) {
+	switch obj := obj.(type) {
+	case *types.Var:
+		pkg := prog.Package(qinfo.Pkg)
+		pkg.Build()
+		if v, addr := prog.VarValue(obj, pkg, path); v != nil {
+			return v, addr, nil
+		}
+		return nil, false, fmt.Errorf("can't locate SSA Value for var %s", obj.Name())
+
+	case *types.Func:
+		fn := prog.FuncValue(obj)
+		if fn == nil {
+			return nil, false, fmt.Errorf("%s is an interface method", obj)
+		}
+		// TODO(adonovan): there's no point running PTA on a *Func ident.
+		// Eliminate this feature.
+		return fn, false, nil
+	}
+	panic(obj)
+}
+
+// ssaValueForExpr returns the ssa.Value of the non-ast.Ident
+// expression whose path to the root of the AST is path.
+//
+func ssaValueForExpr(prog *ssa.Program, qinfo *loader.PackageInfo, path []ast.Node) (value ssa.Value, isAddr bool, err error) {
+	pkg := prog.Package(qinfo.Pkg)
+	pkg.SetDebugMode(true)
+	pkg.Build()
+
+	fn := ssa.EnclosingFunction(pkg, path)
+	if fn == nil {
+		return nil, false, fmt.Errorf("no SSA function built for this location (dead code?)")
+	}
+
+	if v, addr := fn.ValueForExpr(path[0].(ast.Expr)); v != nil {
+		return v, addr, nil
+	}
+
+	return nil, false, fmt.Errorf("can't locate SSA Value for expression in %s", fn)
+}
+
+// runPTA runs the pointer analysis of the selected SSA value or address.
+func runPTA(conf *pointer.Config, v ssa.Value, isAddr bool) (ptrs []pointerResult, err error) {
+	T := v.Type()
+	if isAddr {
+		conf.AddIndirectQuery(v)
+		T = deref(T)
+	} else {
+		conf.AddQuery(v)
+	}
+	ptares := ptrAnalysis(conf)
+
+	var ptr pointer.Pointer
+	if isAddr {
+		ptr = ptares.IndirectQueries[v]
+	} else {
+		ptr = ptares.Queries[v]
+	}
+	if ptr == (pointer.Pointer{}) {
+		return nil, fmt.Errorf("pointer analysis did not find expression (dead code?)")
+	}
+	pts := ptr.PointsTo()
+
+	if pointer.CanHaveDynamicTypes(T) {
+		// Show concrete types for interface/reflect.Value expression.
+		if concs := pts.DynamicTypes(); concs.Len() > 0 {
+			concs.Iterate(func(conc types.Type, pta interface{}) {
+				labels := pta.(pointer.PointsToSet).Labels()
+				sort.Sort(byPosAndString(labels)) // to ensure determinism
+				ptrs = append(ptrs, pointerResult{conc, labels})
+			})
+		}
+	} else {
+		// Show labels for other expressions.
+		labels := pts.Labels()
+		sort.Sort(byPosAndString(labels)) // to ensure determinism
+		ptrs = append(ptrs, pointerResult{T, labels})
+	}
+	sort.Sort(byTypeString(ptrs)) // to ensure determinism
+	return ptrs, nil
+}
+
+type pointerResult struct {
+	typ    types.Type       // type of the pointer (always concrete)
+	labels []*pointer.Label // set of labels
+}
+
+type pointstoResult struct {
+	qpos *queryPos
+	typ  types.Type      // type of expression
+	ptrs []pointerResult // pointer info (typ is concrete => len==1)
+}
+
+func (r *pointstoResult) display(printf printfFunc) {
+	if pointer.CanHaveDynamicTypes(r.typ) {
+		// Show concrete types for interface, reflect.Type or
+		// reflect.Value expression.
+
+		if len(r.ptrs) > 0 {
+			printf(r.qpos, "this %s may contain these dynamic types:", r.qpos.typeString(r.typ))
+			for _, ptr := range r.ptrs {
+				var obj types.Object
+				if nt, ok := deref(ptr.typ).(*types.Named); ok {
+					obj = nt.Obj()
+				}
+				if len(ptr.labels) > 0 {
+					printf(obj, "\t%s, may point to:", r.qpos.typeString(ptr.typ))
+					printLabels(printf, ptr.labels, "\t\t")
+				} else {
+					printf(obj, "\t%s", r.qpos.typeString(ptr.typ))
+				}
+			}
+		} else {
+			printf(r.qpos, "this %s cannot contain any dynamic types.", r.typ)
+		}
+	} else {
+		// Show labels for other expressions.
+		if ptr := r.ptrs[0]; len(ptr.labels) > 0 {
+			printf(r.qpos, "this %s may point to these objects:",
+				r.qpos.typeString(r.typ))
+			printLabels(printf, ptr.labels, "\t")
+		} else {
+			printf(r.qpos, "this %s may not point to anything.",
+				r.qpos.typeString(r.typ))
+		}
+	}
+}
+
+func (r *pointstoResult) toSerial(res *serial.Result, fset *token.FileSet) {
+	var pts []serial.PointsTo
+	for _, ptr := range r.ptrs {
+		var namePos string
+		if nt, ok := deref(ptr.typ).(*types.Named); ok {
+			namePos = fset.Position(nt.Obj().Pos()).String()
+		}
+		var labels []serial.PointsToLabel
+		for _, l := range ptr.labels {
+			labels = append(labels, serial.PointsToLabel{
+				Pos:  fset.Position(l.Pos()).String(),
+				Desc: l.String(),
+			})
+		}
+		pts = append(pts, serial.PointsTo{
+			Type:    r.qpos.typeString(ptr.typ),
+			NamePos: namePos,
+			Labels:  labels,
+		})
+	}
+	res.PointsTo = pts
+}
+
+type byTypeString []pointerResult
+
+func (a byTypeString) Len() int           { return len(a) }
+func (a byTypeString) Less(i, j int) bool { return a[i].typ.String() < a[j].typ.String() }
+func (a byTypeString) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }
+
+type byPosAndString []*pointer.Label
+
+func (a byPosAndString) Len() int { return len(a) }
+func (a byPosAndString) Less(i, j int) bool {
+	cmp := a[i].Pos() - a[j].Pos()
+	return cmp < 0 || (cmp == 0 && a[i].String() < a[j].String())
+}
+func (a byPosAndString) Swap(i, j int) { a[i], a[j] = a[j], a[i] }
+
+func printLabels(printf printfFunc, labels []*pointer.Label, prefix string) {
+	// TODO(adonovan): due to context-sensitivity, many of these
+	// labels may differ only by context, which isn't apparent.
+	for _, label := range labels {
+		printf(label, "%s%s", prefix, label)
+	}
+}

vendor/github.com/visualfc/gotools/oracle/oracle/pos.go

@@ -0,0 +1,143 @@
+package oracle
+
+// This file defines utilities for working with file positions.
+
+import (
+	"fmt"
+	"go/parser"
+	"go/token"
+	"os"
+	"path/filepath"
+	"strconv"
+	"strings"
+
+	"golang.org/x/tools/go/ast/astutil"
+)
+
+// parseOctothorpDecimal returns the numeric value if s matches "#%d",
+// otherwise -1.
+func parseOctothorpDecimal(s string) int {
+	if s != "" && s[0] == '#' {
+		if s, err := strconv.ParseInt(s[1:], 10, 32); err == nil {
+			return int(s)
+		}
+	}
+	return -1
+}
+
+// parsePosFlag parses a string of the form "file:pos" or
+// file:start,end" where pos, start, end match #%d and represent byte
+// offsets, and returns its components.
+//
+// (Numbers without a '#' prefix are reserved for future use,
+// e.g. to indicate line/column positions.)
+//
+func parsePosFlag(posFlag string) (filename string, startOffset, endOffset int, err error) {
+	if posFlag == "" {
+		err = fmt.Errorf("no source position specified (-pos flag)")
+		return
+	}
+
+	colon := strings.LastIndex(posFlag, ":")
+	if colon < 0 {
+		err = fmt.Errorf("invalid source position -pos=%q", posFlag)
+		return
+	}
+	filename, offset := posFlag[:colon], posFlag[colon+1:]
+	startOffset = -1
+	endOffset = -1
+	if hyphen := strings.Index(offset, ","); hyphen < 0 {
+		// e.g. "foo.go:#123"
+		startOffset = parseOctothorpDecimal(offset)
+		endOffset = startOffset
+	} else {
+		// e.g. "foo.go:#123,#456"
+		startOffset = parseOctothorpDecimal(offset[:hyphen])
+		endOffset = parseOctothorpDecimal(offset[hyphen+1:])
+	}
+	if startOffset < 0 || endOffset < 0 {
+		err = fmt.Errorf("invalid -pos offset %q", offset)
+		return
+	}
+	return
+}
+
+// findQueryPos searches fset for filename and translates the
+// specified file-relative byte offsets into token.Pos form.  It
+// returns an error if the file was not found or the offsets were out
+// of bounds.
+//
+func findQueryPos(fset *token.FileSet, filename string, startOffset, endOffset int) (start, end token.Pos, err error) {
+	var file *token.File
+	fset.Iterate(func(f *token.File) bool {
+		if sameFile(filename, f.Name()) {
+			// (f.Name() is absolute)
+			file = f
+			return false // done
+		}
+		return true // continue
+	})
+	if file == nil {
+		err = fmt.Errorf("couldn't find file containing position")
+		return
+	}
+
+	// Range check [start..end], inclusive of both end-points.
+
+	if 0 <= startOffset && startOffset <= file.Size() {
+		start = file.Pos(int(startOffset))
+	} else {
+		err = fmt.Errorf("start position is beyond end of file")
+		return
+	}
+
+	if 0 <= endOffset && endOffset <= file.Size() {
+		end = file.Pos(int(endOffset))
+	} else {
+		err = fmt.Errorf("end position is beyond end of file")
+		return
+	}
+
+	return
+}
+
+// sameFile returns true if x and y have the same basename and denote
+// the same file.
+//
+func sameFile(x, y string) bool {
+	if filepath.Base(x) == filepath.Base(y) { // (optimisation)
+		if xi, err := os.Stat(x); err == nil {
+			if yi, err := os.Stat(y); err == nil {
+				return os.SameFile(xi, yi)
+			}
+		}
+	}
+	return false
+}
+
+// fastQueryPos parses the -pos flag and returns a QueryPos.
+// It parses only a single file, and does not run the type checker.
+func fastQueryPos(posFlag string) (*queryPos, error) {
+	filename, startOffset, endOffset, err := parsePosFlag(posFlag)
+	if err != nil {
+		return nil, err
+	}
+
+	fset := token.NewFileSet()
+	f, err := parser.ParseFile(fset, filename, nil, 0)
+	if err != nil {
+		return nil, err
+	}
+
+	start, end, err := findQueryPos(fset, filename, startOffset, endOffset)
+	if err != nil {
+		return nil, err
+	}
+
+	path, exact := astutil.PathEnclosingInterval(f, start, end)
+	if path == nil {
+		return nil, fmt.Errorf("no syntax here")
+	}
+
+	return &queryPos{fset, start, end, path, exact, nil}, nil
+}

vendor/github.com/visualfc/gotools/oracle/oracle/referrers.go

@@ -0,0 +1,243 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build go1.5
+
+package oracle
+
+import (
+	"bytes"
+	"fmt"
+	"go/ast"
+	"go/token"
+	"go/types"
+	"io/ioutil"
+	"sort"
+
+	"github.com/visualfc/gotools/oracle/oracle/serial"
+	"golang.org/x/tools/go/loader"
+	"golang.org/x/tools/refactor/importgraph"
+)
+
+// Referrers reports all identifiers that resolve to the same object
+// as the queried identifier, within any package in the analysis scope.
+func referrers(q *Query) error {
+	lconf := loader.Config{Build: q.Build}
+	allowErrors(&lconf)
+
+	if _, err := importQueryPackage(q.Pos, &lconf); err != nil {
+		return err
+	}
+
+	var id *ast.Ident
+	var obj types.Object
+	var lprog *loader.Program
+	var pass2 bool
+	var qpos *queryPos
+	for {
+		// Load/parse/type-check the program.
+		var err error
+		lprog, err = lconf.Load()
+		if err != nil {
+			return err
+		}
+		q.Fset = lprog.Fset
+
+		qpos, err = parseQueryPos(lprog, q.Pos, false)
+		if err != nil {
+			return err
+		}
+
+		id, _ = qpos.path[0].(*ast.Ident)
+		if id == nil {
+			return fmt.Errorf("no identifier here")
+		}
+
+		obj = qpos.info.ObjectOf(id)
+		if obj == nil {
+			// Happens for y in "switch y := x.(type)",
+			// the package declaration,
+			// and unresolved identifiers.
+			if _, ok := qpos.path[1].(*ast.File); ok { // package decl?
+				pkg := qpos.info.Pkg
+				obj = types.NewPkgName(id.Pos(), pkg, pkg.Name(), pkg)
+			} else {
+				return fmt.Errorf("no object for identifier: %T", qpos.path[1])
+			}
+		}
+
+		if pass2 {
+			break
+		}
+
+		// If the identifier is exported, we must load all packages that
+		// depend transitively upon the package that defines it.
+		// Treat PkgNames as exported, even though they're lowercase.
+		if _, isPkg := obj.(*types.PkgName); !(isPkg || obj.Exported()) {
+			break // not exported
+		}
+
+		// Scan the workspace and build the import graph.
+		// Ignore broken packages.
+		_, rev, _ := importgraph.Build(q.Build)
+
+		// Re-load the larger program.
+		// Create a new file set so that ...
+		// External test packages are never imported,
+		// so they will never appear in the graph.
+		// (We must reset the Config here, not just reset the Fset field.)
+		lconf = loader.Config{
+			Fset:  token.NewFileSet(),
+			Build: q.Build,
+		}
+		allowErrors(&lconf)
+		for path := range rev.Search(obj.Pkg().Path()) {
+			lconf.ImportWithTests(path)
+		}
+		pass2 = true
+	}
+
+	// Iterate over all go/types' Uses facts for the entire program.
+	var refs []*ast.Ident
+	for _, info := range lprog.AllPackages {
+		for id2, obj2 := range info.Uses {
+			if sameObj(obj, obj2) {
+				refs = append(refs, id2)
+			}
+		}
+	}
+	sort.Sort(byNamePos{q.Fset, refs})
+
+	q.result = &referrersResult{
+		qpos:  qpos,
+		query: id,
+		obj:   obj,
+		refs:  refs,
+	}
+	return nil
+}
+
+// same reports whether x and y are identical, or both are PkgNames
+// that import the same Package.
+//
+func sameObj(x, y types.Object) bool {
+	if x == y {
+		return true
+	}
+	if x, ok := x.(*types.PkgName); ok {
+		if y, ok := y.(*types.PkgName); ok {
+			return x.Imported() == y.Imported()
+		}
+	}
+	return false
+}
+
+// -------- utils --------
+
+// An deterministic ordering for token.Pos that doesn't
+// depend on the order in which packages were loaded.
+func lessPos(fset *token.FileSet, x, y token.Pos) bool {
+	fx := fset.File(x)
+	fy := fset.File(y)
+	if fx != fy {
+		return fx.Name() < fy.Name()
+	}
+	return x < y
+}
+
+type byNamePos struct {
+	fset *token.FileSet
+	ids  []*ast.Ident
+}
+
+func (p byNamePos) Len() int      { return len(p.ids) }
+func (p byNamePos) Swap(i, j int) { p.ids[i], p.ids[j] = p.ids[j], p.ids[i] }
+func (p byNamePos) Less(i, j int) bool {
+	return lessPos(p.fset, p.ids[i].NamePos, p.ids[j].NamePos)
+}
+
+type referrersResult struct {
+	qpos  *queryPos
+	query *ast.Ident   // identifier of query
+	obj   types.Object // object it denotes
+	refs  []*ast.Ident // set of all other references to it
+}
+
+func (r *referrersResult) display(printf printfFunc) {
+	printf(r.obj, "%d references to %s", len(r.refs), r.qpos.objectString(r.obj))
+
+	// Show referring lines, like grep.
+	type fileinfo struct {
+		refs     []*ast.Ident
+		linenums []int            // line number of refs[i]
+		data     chan interface{} // file contents or error
+	}
+	var fileinfos []*fileinfo
+	fileinfosByName := make(map[string]*fileinfo)
+
+	// First pass: start the file reads concurrently.
+	sema := make(chan struct{}, 20) // counting semaphore to limit I/O concurrency
+	for _, ref := range r.refs {
+		posn := r.qpos.fset.Position(ref.Pos())
+		fi := fileinfosByName[posn.Filename]
+		if fi == nil {
+			fi = &fileinfo{data: make(chan interface{})}
+			fileinfosByName[posn.Filename] = fi
+			fileinfos = append(fileinfos, fi)
+
+			// First request for this file:
+			// start asynchronous read.
+			go func() {
+				sema <- struct{}{} // acquire token
+				content, err := ioutil.ReadFile(posn.Filename)
+				<-sema // release token
+				if err != nil {
+					fi.data <- err
+				} else {
+					fi.data <- content
+				}
+			}()
+		}
+		fi.refs = append(fi.refs, ref)
+		fi.linenums = append(fi.linenums, posn.Line)
+	}
+
+	// Second pass: print refs in original order.
+	// One line may have several refs at different columns.
+	for _, fi := range fileinfos {
+		v := <-fi.data // wait for I/O completion
+
+		// Print one item for all refs in a file that could not
+		// be loaded (perhaps due to //line directives).
+		if err, ok := v.(error); ok {
+			var suffix string
+			if more := len(fi.refs) - 1; more > 0 {
+				suffix = fmt.Sprintf(" (+ %d more refs in this file)", more)
+			}
+			printf(fi.refs[0], "%v%s", err, suffix)
+			continue
+		}
+
+		lines := bytes.Split(v.([]byte), []byte("\n"))
+		for i, ref := range fi.refs {
+			printf(ref, "%s", lines[fi.linenums[i]-1])
+		}
+	}
+}
+
+// TODO(adonovan): encode extent, not just Pos info, in Serial form.
+
+func (r *referrersResult) toSerial(res *serial.Result, fset *token.FileSet) {
+	referrers := &serial.Referrers{
+		Pos:  fset.Position(r.query.Pos()).String(),
+		Desc: r.obj.String(),
+	}
+	if pos := r.obj.Pos(); pos != token.NoPos { // Package objects have no Pos()
+		referrers.ObjPos = fset.Position(pos).String()
+	}
+	for _, ref := range r.refs {
+		referrers.Refs = append(referrers.Refs, fset.Position(ref.NamePos).String())
+	}
+	res.Referrers = referrers
+}

vendor/github.com/visualfc/gotools/oracle/oracle/serial/serial.go

@@ -0,0 +1,258 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package serial defines the oracle's schema for structured data
+// serialization using JSON, XML, etc.
+package serial
+
+// All 'pos' strings are of the form "file:line:col".
+// TODO(adonovan): improve performance by sharing filename strings.
+// TODO(adonovan): improve precision by providing the start/end
+// interval when available.
+//
+// TODO(adonovan): consider richer encodings of types, functions,
+// methods, etc.
+
+// A Peers is the result of a 'peers' query.
+// If Allocs is empty, the selected channel can't point to anything.
+type Peers struct {
+	Pos      string   `json:"pos"`                // location of the selected channel op (<-)
+	Type     string   `json:"type"`               // type of the selected channel
+	Allocs   []string `json:"allocs,omitempty"`   // locations of aliased make(chan) ops
+	Sends    []string `json:"sends,omitempty"`    // locations of aliased ch<-x ops
+	Receives []string `json:"receives,omitempty"` // locations of aliased <-ch ops
+	Closes   []string `json:"closes,omitempty"`   // locations of aliased close(ch) ops
+}
+
+// A Referrers is the result of a 'referrers' query.
+type Referrers struct {
+	Pos    string   `json:"pos"`              // location of the query reference
+	ObjPos string   `json:"objpos,omitempty"` // location of the definition
+	Desc   string   `json:"desc"`             // description of the denoted object
+	Refs   []string `json:"refs,omitempty"`   // locations of all references
+}
+
+// A Definition is the result of a 'definition' query.
+type Definition struct {
+	ObjPos string `json:"objpos,omitempty"` // location of the definition
+	Desc   string `json:"desc"`             // description of the denoted object
+}
+
+type CalleesItem struct {
+	Name string `json:"name"` // full name of called function
+	Pos  string `json:"pos"`  // location of called function
+}
+
+// A Callees is the result of a 'callees' query.
+//
+// Callees is nonempty unless the call was a dynamic call on a
+// provably nil func or interface value.
+type Callees struct {
+	Pos     string         `json:"pos"`               // location of selected call site
+	Desc    string         `json:"desc"`              // description of call site
+	Callees []*CalleesItem `json:"callees,omitempty"` // set of possible call targets
+}
+
+// A Caller is one element of the slice returned by a 'callers' query.
+// (Callstack also contains a similar slice.)
+//
+// The root of the callgraph has an unspecified "Caller" string.
+type Caller struct {
+	Pos    string `json:"pos,omitempty"` // location of the calling function
+	Desc   string `json:"desc"`          // description of call site
+	Caller string `json:"caller"`        // full name of calling function
+}
+
+// A CallStack is the result of a 'callstack' query.
+// It indicates an arbitrary path from the root of the callgraph to
+// the query function.
+//
+// If the Callers slice is empty, the function was unreachable in this
+// analysis scope.
+type CallStack struct {
+	Pos     string   `json:"pos"`     // location of the selected function
+	Target  string   `json:"target"`  // the selected function
+	Callers []Caller `json:"callers"` // enclosing calls, innermost first.
+}
+
+// A FreeVar is one element of the slice returned by a 'freevars'
+// query.  Each one identifies an expression referencing a local
+// identifier defined outside the selected region.
+type FreeVar struct {
+	Pos  string `json:"pos"`  // location of the identifier's definition
+	Kind string `json:"kind"` // one of {var,func,type,const,label}
+	Ref  string `json:"ref"`  // referring expression (e.g. "x" or "x.y.z")
+	Type string `json:"type"` // type of the expression
+}
+
+// An Implements contains the result of an 'implements' query.
+// It describes the queried type, the set of named non-empty interface
+// types to which it is assignable, and the set of named/*named types
+// (concrete or non-empty interface) which may be assigned to it.
+//
+type Implements struct {
+	T                 ImplementsType   `json:"type,omitempty"`    // the queried type
+	AssignableTo      []ImplementsType `json:"to,omitempty"`      // types assignable to T
+	AssignableFrom    []ImplementsType `json:"from,omitempty"`    // interface types assignable from T
+	AssignableFromPtr []ImplementsType `json:"fromptr,omitempty"` // interface types assignable only from *T
+
+	// The following fields are set only if the query was a method.
+	// Assignable{To,From,FromPtr}Method[i] is the corresponding
+	// method of type Assignable{To,From,FromPtr}[i], or blank
+	// {"",""} if that type lacks the method.
+	Method                  *DescribeMethod  `json:"method,omitempty"` //  the queried method
+	AssignableToMethod      []DescribeMethod `json:"to_method,omitempty"`
+	AssignableFromMethod    []DescribeMethod `json:"from_method,omitempty"`
+	AssignableFromPtrMethod []DescribeMethod `json:"fromptr_method,omitempty"`
+}
+
+// An ImplementsType describes a single type as part of an 'implements' query.
+type ImplementsType struct {
+	Name string `json:"name"` // full name of the type
+	Pos  string `json:"pos"`  // location of its definition
+	Kind string `json:"kind"` // "basic", "array", etc
+}
+
+// A SyntaxNode is one element of a stack of enclosing syntax nodes in
+// a "what" query.
+type SyntaxNode struct {
+	Description string `json:"desc"`  // description of syntax tree
+	Start       int    `json:"start"` // start byte offset, 0-based
+	End         int    `json:"end"`   // end byte offset
+}
+
+// A What is the result of the "what" query, which quickly identifies
+// the selection, parsing only a single file.  It is intended for use
+// in low-latency GUIs.
+type What struct {
+	Enclosing  []SyntaxNode `json:"enclosing"`            // enclosing nodes of syntax tree
+	Modes      []string     `json:"modes"`                // query modes enabled for this selection.
+	SrcDir     string       `json:"srcdir,omitempty"`     // $GOROOT src directory containing queried package
+	ImportPath string       `json:"importpath,omitempty"` // import path of queried package
+}
+
+// A PointsToLabel describes a pointer analysis label.
+//
+// A "label" is an object that may be pointed to by a pointer, map,
+// channel, 'func', slice or interface.  Labels include:
+//    - functions
+//    - globals
+//    - arrays created by literals (e.g. []byte("foo")) and conversions ([]byte(s))
+//    - stack- and heap-allocated variables (including composite literals)
+//    - arrays allocated by append()
+//    - channels, maps and arrays created by make()
+//    - and their subelements, e.g. "alloc.y[*].z"
+//
+type PointsToLabel struct {
+	Pos  string `json:"pos"`  // location of syntax that allocated the object
+	Desc string `json:"desc"` // description of the label
+}
+
+// A PointsTo is one element of the result of a 'pointsto' query on an
+// expression.  It describes a single pointer: its type and the set of
+// "labels" it points to.
+//
+// If the pointer is of interface type, it will have one PTS entry
+// describing each concrete type that it may contain.  For each
+// concrete type that is a pointer, the PTS entry describes the labels
+// it may point to.  The same is true for reflect.Values, except the
+// dynamic types needn't be concrete.
+//
+type PointsTo struct {
+	Type    string          `json:"type"`              // (concrete) type of the pointer
+	NamePos string          `json:"namepos,omitempty"` // location of type defn, if Named
+	Labels  []PointsToLabel `json:"labels,omitempty"`  // pointed-to objects
+}
+
+// A DescribeValue is the additional result of a 'describe' query
+// if the selection indicates a value or expression.
+type DescribeValue struct {
+	Type   string `json:"type"`             // type of the expression
+	Value  string `json:"value,omitempty"`  // value of the expression, if constant
+	ObjPos string `json:"objpos,omitempty"` // location of the definition, if an Ident
+}
+
+type DescribeMethod struct {
+	Name string `json:"name"` // method name, as defined by types.Selection.String()
+	Pos  string `json:"pos"`  // location of the method's definition
+}
+
+// A DescribeType is the additional result of a 'describe' query
+// if the selection indicates a type.
+type DescribeType struct {
+	Type    string           `json:"type"`              // the string form of the type
+	NamePos string           `json:"namepos,omitempty"` // location of definition of type, if named
+	NameDef string           `json:"namedef,omitempty"` // underlying definition of type, if named
+	Methods []DescribeMethod `json:"methods,omitempty"` // methods of the type
+}
+
+type DescribeMember struct {
+	Name    string           `json:"name"`              // name of member
+	Type    string           `json:"type,omitempty"`    // type of member (underlying, if 'type')
+	Value   string           `json:"value,omitempty"`   // value of member (if 'const')
+	Pos     string           `json:"pos"`               // location of definition of member
+	Kind    string           `json:"kind"`              // one of {var,const,func,type}
+	Methods []DescribeMethod `json:"methods,omitempty"` // methods (if member is a type)
+}
+
+// A DescribePackage is the additional result of a 'describe' if
+// the selection indicates a package.
+type DescribePackage struct {
+	Path    string            `json:"path"`              // import path of the package
+	Members []*DescribeMember `json:"members,omitempty"` // accessible members of the package
+}
+
+// A Describe is the result of a 'describe' query.
+// It may contain an element describing the selected semantic entity
+// in detail.
+type Describe struct {
+	Desc   string `json:"desc"`             // description of the selected syntax node
+	Pos    string `json:"pos"`              // location of the selected syntax node
+	Detail string `json:"detail,omitempty"` // one of {package, type, value}, or "".
+
+	// At most one of the following fields is populated:
+	// the one specified by 'detail'.
+	Package *DescribePackage `json:"package,omitempty"`
+	Type    *DescribeType    `json:"type,omitempty"`
+	Value   *DescribeValue   `json:"value,omitempty"`
+}
+
+// A WhichErrs is the result of a 'whicherrs' query.
+// It contains the position of the queried error and the possible globals,
+// constants, and types it may point to.
+type WhichErrs struct {
+	ErrPos    string          `json:"errpos,omitempty"`    // location of queried error
+	Globals   []string        `json:"globals,omitempty"`   // locations of globals
+	Constants []string        `json:"constants,omitempty"` // locations of constants
+	Types     []WhichErrsType `json:"types,omitempty"`     // Types
+}
+
+type WhichErrsType struct {
+	Type     string `json:"type,omitempty"`
+	Position string `json:"position,omitempty"`
+}
+
+// A Result is the common result of any oracle query.
+// It contains a query-specific result element.
+//
+// TODO(adonovan): perhaps include other info such as: analysis scope,
+// raw query position, stack of ast nodes, query package, etc.
+type Result struct {
+	Mode string `json:"mode"` // mode of the query
+
+	// Exactly one of the following fields is populated:
+	// the one specified by 'mode'.
+	Callees    *Callees    `json:"callees,omitempty"`
+	Callers    []Caller    `json:"callers,omitempty"`
+	Callstack  *CallStack  `json:"callstack,omitempty"`
+	Definition *Definition `json:"definition,omitempty"`
+	Describe   *Describe   `json:"describe,omitempty"`
+	Freevars   []*FreeVar  `json:"freevars,omitempty"`
+	Implements *Implements `json:"implements,omitempty"`
+	Peers      *Peers      `json:"peers,omitempty"`
+	PointsTo   []PointsTo  `json:"pointsto,omitempty"`
+	Referrers  *Referrers  `json:"referrers,omitempty"`
+	What       *What       `json:"what,omitempty"`
+	WhichErrs  *WhichErrs  `json:"whicherrs,omitempty"`
+}

vendor/github.com/visualfc/gotools/oracle/oracle/what.go

@@ -0,0 +1,210 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package oracle
+
+import (
+	"fmt"
+	"go/ast"
+	"go/build"
+	"go/token"
+	"os"
+	"path/filepath"
+	"sort"
+	"strings"
+
+	"github.com/visualfc/gotools/oracle/oracle/serial"
+	"golang.org/x/tools/go/ast/astutil"
+)
+
+// what reports all the information about the query selection that can be
+// obtained from parsing only its containing source file.
+// It is intended to be a very low-latency query callable from GUI
+// tools, e.g. to populate a menu of options of slower queries about
+// the selected location.
+//
+func what(q *Query) error {
+	qpos, err := fastQueryPos(q.Pos)
+	if err != nil {
+		return err
+	}
+	q.Fset = qpos.fset
+
+	// (ignore errors)
+	srcdir, importPath, _ := guessImportPath(q.Fset.File(qpos.start).Name(), q.Build)
+
+	// Determine which query modes are applicable to the selection.
+	enable := map[string]bool{
+		"describe": true, // any syntax; always enabled
+	}
+
+	if qpos.end > qpos.start {
+		enable["freevars"] = true // nonempty selection?
+	}
+
+	for _, n := range qpos.path {
+		switch n := n.(type) {
+		case *ast.Ident:
+			enable["definition"] = true
+			enable["referrers"] = true
+			enable["implements"] = true
+		case *ast.CallExpr:
+			enable["callees"] = true
+		case *ast.FuncDecl:
+			enable["callers"] = true
+			enable["callstack"] = true
+		case *ast.SendStmt:
+			enable["peers"] = true
+		case *ast.UnaryExpr:
+			if n.Op == token.ARROW {
+				enable["peers"] = true
+			}
+		}
+
+		// For implements, we approximate findInterestingNode.
+		if _, ok := enable["implements"]; !ok {
+			switch n.(type) {
+			case *ast.ArrayType,
+				*ast.StructType,
+				*ast.FuncType,
+				*ast.InterfaceType,
+				*ast.MapType,
+				*ast.ChanType:
+				enable["implements"] = true
+			}
+		}
+
+		// For pointsto, we approximate findInterestingNode.
+		if _, ok := enable["pointsto"]; !ok {
+			switch n.(type) {
+			case ast.Stmt,
+				*ast.ArrayType,
+				*ast.StructType,
+				*ast.FuncType,
+				*ast.InterfaceType,
+				*ast.MapType,
+				*ast.ChanType:
+				enable["pointsto"] = false // not an expr
+
+			case ast.Expr, ast.Decl, *ast.ValueSpec:
+				enable["pointsto"] = true // an expr, maybe
+
+			default:
+				// Comment, Field, KeyValueExpr, etc: ascend.
+			}
+		}
+	}
+
+	// If we don't have an exact selection, disable modes that need one.
+	if !qpos.exact {
+		enable["callees"] = false
+		enable["pointsto"] = false
+		enable["whicherrs"] = false
+		enable["describe"] = false
+	}
+
+	var modes []string
+	for mode := range enable {
+		modes = append(modes, mode)
+	}
+	sort.Strings(modes)
+
+	q.result = &whatResult{
+		path:       qpos.path,
+		srcdir:     srcdir,
+		importPath: importPath,
+		modes:      modes,
+	}
+	return nil
+}
+
+// guessImportPath finds the package containing filename, and returns
+// its source directory (an element of $GOPATH) and its import path
+// relative to it.
+//
+// TODO(adonovan): what about _test.go files that are not part of the
+// package?
+//
+func guessImportPath(filename string, buildContext *build.Context) (srcdir, importPath string, err error) {
+	absFile, err := filepath.Abs(filename)
+	if err != nil {
+		err = fmt.Errorf("can't form absolute path of %s", filename)
+		return
+	}
+	absFileDir := segments(filepath.Dir(absFile))
+
+	// Find the innermost directory in $GOPATH that encloses filename.
+	minD := 1024
+	for _, gopathDir := range buildContext.SrcDirs() {
+		absDir, err := filepath.Abs(gopathDir)
+		if err != nil {
+			continue // e.g. non-existent dir on $GOPATH
+		}
+		d := prefixLen(segments(absDir), absFileDir)
+		// If there are multiple matches,
+		// prefer the innermost enclosing directory
+		// (smallest d).
+		if d >= 0 && d < minD {
+			minD = d
+			srcdir = gopathDir
+			importPath = strings.Join(absFileDir[len(absFileDir)-minD:], string(os.PathSeparator))
+		}
+	}
+	if srcdir == "" {
+		err = fmt.Errorf("directory %s is not beneath any of these GOROOT/GOPATH directories: %s",
+			filepath.Dir(absFile), strings.Join(buildContext.SrcDirs(), ", "))
+	}
+	return
+}
+
+func segments(path string) []string {
+	return strings.Split(path, string(os.PathSeparator))
+}
+
+// prefixLen returns the length of the remainder of y if x is a prefix
+// of y, a negative number otherwise.
+func prefixLen(x, y []string) int {
+	d := len(y) - len(x)
+	if d >= 0 {
+		for i := range x {
+			if y[i] != x[i] {
+				return -1 // not a prefix
+			}
+		}
+	}
+	return d
+}
+
+type whatResult struct {
+	path       []ast.Node
+	modes      []string
+	srcdir     string
+	importPath string
+}
+
+func (r *whatResult) display(printf printfFunc) {
+	for _, n := range r.path {
+		printf(n, "%s", astutil.NodeDescription(n))
+	}
+	printf(nil, "modes: %s", r.modes)
+	printf(nil, "srcdir: %s", r.srcdir)
+	printf(nil, "import path: %s", r.importPath)
+}
+
+func (r *whatResult) toSerial(res *serial.Result, fset *token.FileSet) {
+	var enclosing []serial.SyntaxNode
+	for _, n := range r.path {
+		enclosing = append(enclosing, serial.SyntaxNode{
+			Description: astutil.NodeDescription(n),
+			Start:       fset.Position(n.Pos()).Offset,
+			End:         fset.Position(n.End()).Offset,
+		})
+	}
+	res.What = &serial.What{
+		Modes:      r.modes,
+		SrcDir:     r.srcdir,
+		ImportPath: r.importPath,
+		Enclosing:  enclosing,
+	}
+}

vendor/github.com/visualfc/gotools/oracle/oracle/whicherrs.go

@@ -0,0 +1,328 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build go1.5
+
+package oracle
+
+import (
+	"fmt"
+	"go/ast"
+	"go/token"
+	"go/types"
+	"sort"
+
+	"github.com/visualfc/gotools/oracle/oracle/serial"
+	"golang.org/x/tools/go/ast/astutil"
+	"golang.org/x/tools/go/loader"
+	"golang.org/x/tools/go/ssa"
+	"golang.org/x/tools/go/ssa/ssautil"
+)
+
+var builtinErrorType = types.Universe.Lookup("error").Type()
+
+// whicherrs takes an position to an error and tries to find all types, constants
+// and global value which a given error can point to and which can be checked from the
+// scope where the error lives.
+// In short, it returns a list of things that can be checked against in order to handle
+// an error properly.
+//
+// TODO(dmorsing): figure out if fields in errors like *os.PathError.Err
+// can be queried recursively somehow.
+func whicherrs(q *Query) error {
+	lconf := loader.Config{Build: q.Build}
+
+	if err := setPTAScope(&lconf, q.Scope); err != nil {
+		return err
+	}
+
+	// Load/parse/type-check the program.
+	lprog, err := lconf.Load()
+	if err != nil {
+		return err
+	}
+	q.Fset = lprog.Fset
+
+	qpos, err := parseQueryPos(lprog, q.Pos, true) // needs exact pos
+	if err != nil {
+		return err
+	}
+
+	prog := ssautil.CreateProgram(lprog, ssa.GlobalDebug)
+
+	ptaConfig, err := setupPTA(prog, lprog, q.PTALog, q.Reflection)
+	if err != nil {
+		return err
+	}
+
+	path, action := findInterestingNode(qpos.info, qpos.path)
+	if action != actionExpr {
+		return fmt.Errorf("whicherrs wants an expression; got %s",
+			astutil.NodeDescription(qpos.path[0]))
+	}
+	var expr ast.Expr
+	var obj types.Object
+	switch n := path[0].(type) {
+	case *ast.ValueSpec:
+		// ambiguous ValueSpec containing multiple names
+		return fmt.Errorf("multiple value specification")
+	case *ast.Ident:
+		obj = qpos.info.ObjectOf(n)
+		expr = n
+	case ast.Expr:
+		expr = n
+	default:
+		return fmt.Errorf("unexpected AST for expr: %T", n)
+	}
+
+	typ := qpos.info.TypeOf(expr)
+	if !types.Identical(typ, builtinErrorType) {
+		return fmt.Errorf("selection is not an expression of type 'error'")
+	}
+	// Determine the ssa.Value for the expression.
+	var value ssa.Value
+	if obj != nil {
+		// def/ref of func/var object
+		value, _, err = ssaValueForIdent(prog, qpos.info, obj, path)
+	} else {
+		value, _, err = ssaValueForExpr(prog, qpos.info, path)
+	}
+	if err != nil {
+		return err // e.g. trivially dead code
+	}
+
+	// Defer SSA construction till after errors are reported.
+	prog.Build()
+
+	globals := findVisibleErrs(prog, qpos)
+	constants := findVisibleConsts(prog, qpos)
+
+	res := &whicherrsResult{
+		qpos:   qpos,
+		errpos: expr.Pos(),
+	}
+
+	// TODO(adonovan): the following code is heavily duplicated
+	// w.r.t.  "pointsto".  Refactor?
+
+	// Find the instruction which initialized the
+	// global error. If more than one instruction has stored to the global
+	// remove the global from the set of values that we want to query.
+	allFuncs := ssautil.AllFunctions(prog)
+	for fn := range allFuncs {
+		for _, b := range fn.Blocks {
+			for _, instr := range b.Instrs {
+				store, ok := instr.(*ssa.Store)
+				if !ok {
+					continue
+				}
+				gval, ok := store.Addr.(*ssa.Global)
+				if !ok {
+					continue
+				}
+				gbl, ok := globals[gval]
+				if !ok {
+					continue
+				}
+				// we already found a store to this global
+				// The normal error define is just one store in the init
+				// so we just remove this global from the set we want to query
+				if gbl != nil {
+					delete(globals, gval)
+				}
+				globals[gval] = store.Val
+			}
+		}
+	}
+
+	ptaConfig.AddQuery(value)
+	for _, v := range globals {
+		ptaConfig.AddQuery(v)
+	}
+
+	ptares := ptrAnalysis(ptaConfig)
+	valueptr := ptares.Queries[value]
+	for g, v := range globals {
+		ptr, ok := ptares.Queries[v]
+		if !ok {
+			continue
+		}
+		if !ptr.MayAlias(valueptr) {
+			continue
+		}
+		res.globals = append(res.globals, g)
+	}
+	pts := valueptr.PointsTo()
+	dedup := make(map[*ssa.NamedConst]bool)
+	for _, label := range pts.Labels() {
+		// These values are either MakeInterfaces or reflect
+		// generated interfaces. For the purposes of this
+		// analysis, we don't care about reflect generated ones
+		makeiface, ok := label.Value().(*ssa.MakeInterface)
+		if !ok {
+			continue
+		}
+		constval, ok := makeiface.X.(*ssa.Const)
+		if !ok {
+			continue
+		}
+		c := constants[*constval]
+		if c != nil && !dedup[c] {
+			dedup[c] = true
+			res.consts = append(res.consts, c)
+		}
+	}
+	concs := pts.DynamicTypes()
+	concs.Iterate(func(conc types.Type, _ interface{}) {
+		// go/types is a bit annoying here.
+		// We want to find all the types that we can
+		// typeswitch or assert to. This means finding out
+		// if the type pointed to can be seen by us.
+		//
+		// For the purposes of this analysis, the type is always
+		// either a Named type or a pointer to one.
+		// There are cases where error can be implemented
+		// by unnamed types, but in that case, we can't assert to
+		// it, so we don't care about it for this analysis.
+		var name *types.TypeName
+		switch t := conc.(type) {
+		case *types.Pointer:
+			named, ok := t.Elem().(*types.Named)
+			if !ok {
+				return
+			}
+			name = named.Obj()
+		case *types.Named:
+			name = t.Obj()
+		default:
+			return
+		}
+		if !isAccessibleFrom(name, qpos.info.Pkg) {
+			return
+		}
+		res.types = append(res.types, &errorType{conc, name})
+	})
+	sort.Sort(membersByPosAndString(res.globals))
+	sort.Sort(membersByPosAndString(res.consts))
+	sort.Sort(sorterrorType(res.types))
+
+	q.result = res
+	return nil
+}
+
+// findVisibleErrs returns a mapping from each package-level variable of type "error" to nil.
+func findVisibleErrs(prog *ssa.Program, qpos *queryPos) map[*ssa.Global]ssa.Value {
+	globals := make(map[*ssa.Global]ssa.Value)
+	for _, pkg := range prog.AllPackages() {
+		for _, mem := range pkg.Members {
+			gbl, ok := mem.(*ssa.Global)
+			if !ok {
+				continue
+			}
+			gbltype := gbl.Type()
+			// globals are always pointers
+			if !types.Identical(deref(gbltype), builtinErrorType) {
+				continue
+			}
+			if !isAccessibleFrom(gbl.Object(), qpos.info.Pkg) {
+				continue
+			}
+			globals[gbl] = nil
+		}
+	}
+	return globals
+}
+
+// findVisibleConsts returns a mapping from each package-level constant assignable to type "error", to nil.
+func findVisibleConsts(prog *ssa.Program, qpos *queryPos) map[ssa.Const]*ssa.NamedConst {
+	constants := make(map[ssa.Const]*ssa.NamedConst)
+	for _, pkg := range prog.AllPackages() {
+		for _, mem := range pkg.Members {
+			obj, ok := mem.(*ssa.NamedConst)
+			if !ok {
+				continue
+			}
+			consttype := obj.Type()
+			if !types.AssignableTo(consttype, builtinErrorType) {
+				continue
+			}
+			if !isAccessibleFrom(obj.Object(), qpos.info.Pkg) {
+				continue
+			}
+			constants[*obj.Value] = obj
+		}
+	}
+
+	return constants
+}
+
+type membersByPosAndString []ssa.Member
+
+func (a membersByPosAndString) Len() int { return len(a) }
+func (a membersByPosAndString) Less(i, j int) bool {
+	cmp := a[i].Pos() - a[j].Pos()
+	return cmp < 0 || cmp == 0 && a[i].String() < a[j].String()
+}
+func (a membersByPosAndString) Swap(i, j int) { a[i], a[j] = a[j], a[i] }
+
+type sorterrorType []*errorType
+
+func (a sorterrorType) Len() int { return len(a) }
+func (a sorterrorType) Less(i, j int) bool {
+	cmp := a[i].obj.Pos() - a[j].obj.Pos()
+	return cmp < 0 || cmp == 0 && a[i].typ.String() < a[j].typ.String()
+}
+func (a sorterrorType) Swap(i, j int) { a[i], a[j] = a[j], a[i] }
+
+type errorType struct {
+	typ types.Type      // concrete type N or *N that implements error
+	obj *types.TypeName // the named type N
+}
+
+type whicherrsResult struct {
+	qpos    *queryPos
+	errpos  token.Pos
+	globals []ssa.Member
+	consts  []ssa.Member
+	types   []*errorType
+}
+
+func (r *whicherrsResult) display(printf printfFunc) {
+	if len(r.globals) > 0 {
+		printf(r.qpos, "this error may point to these globals:")
+		for _, g := range r.globals {
+			printf(g.Pos(), "\t%s", g.RelString(r.qpos.info.Pkg))
+		}
+	}
+	if len(r.consts) > 0 {
+		printf(r.qpos, "this error may contain these constants:")
+		for _, c := range r.consts {
+			printf(c.Pos(), "\t%s", c.RelString(r.qpos.info.Pkg))
+		}
+	}
+	if len(r.types) > 0 {
+		printf(r.qpos, "this error may contain these dynamic types:")
+		for _, t := range r.types {
+			printf(t.obj.Pos(), "\t%s", r.qpos.typeString(t.typ))
+		}
+	}
+}
+
+func (r *whicherrsResult) toSerial(res *serial.Result, fset *token.FileSet) {
+	we := &serial.WhichErrs{}
+	we.ErrPos = fset.Position(r.errpos).String()
+	for _, g := range r.globals {
+		we.Globals = append(we.Globals, fset.Position(g.Pos()).String())
+	}
+	for _, c := range r.consts {
+		we.Constants = append(we.Constants, fset.Position(c.Pos()).String())
+	}
+	for _, t := range r.types {
+		var et serial.WhichErrsType
+		et.Type = r.qpos.typeString(t.typ)
+		et.Position = fset.Position(t.obj.Pos()).String()
+		we.Types = append(we.Types, et)
+	}
+	res.WhichErrs = we
+}

vendor/github.com/visualfc/gotools/pkgs/pkgs.go

@@ -21,9 +21,9 @@ import (
 
 var Command = &command.Command{
 	Run:       runPkgs,
-	UsageLine: "pkgs",
+	UsageLine: "pkgs [-list|-json] [-std]",
-	Short:     "print liteide_stub version",
+	Short:     "print go package",
-	Long:      `Version prints the liteide_stub version.`,
+	Long:      `print go package.`,
 }
 
 var (

vendor/github.com/visualfc/gotools/pkgutil/pkgutil.go

@@ -0,0 +1,233 @@
+package pkgutil
+
+import (
+	"go/build"
+	"io/ioutil"
+	"log"
+	"os"
+	"path/filepath"
+	"regexp"
+	"strings"
+)
+
+//var go15VendorExperiment = os.Getenv("GO15VENDOREXPERIMENT") == "1"
+
+func IsVendorExperiment() bool {
+	return true
+}
+
+// matchPattern(pattern)(name) reports whether
+// name matches pattern.  Pattern is a limited glob
+// pattern in which '...' means 'any string' and there
+// is no other special syntax.
+func matchPattern(pattern string) func(name string) bool {
+	re := regexp.QuoteMeta(pattern)
+	re = strings.Replace(re, `\.\.\.`, `.*`, -1)
+	// Special case: foo/... matches foo too.
+	if strings.HasSuffix(re, `/.*`) {
+		re = re[:len(re)-len(`/.*`)] + `(/.*)?`
+	}
+	reg := regexp.MustCompile(`^` + re + `$`)
+	return func(name string) bool {
+		return reg.MatchString(name)
+	}
+}
+
+// hasPathPrefix reports whether the path s begins with the
+// elements in prefix.
+func hasPathPrefix(s, prefix string) bool {
+	switch {
+	default:
+		return false
+	case len(s) == len(prefix):
+		return s == prefix
+	case len(s) > len(prefix):
+		if prefix != "" && prefix[len(prefix)-1] == '/' {
+			return strings.HasPrefix(s, prefix)
+		}
+		return s[len(prefix)] == '/' && s[:len(prefix)] == prefix
+	}
+}
+
+// hasFilePathPrefix reports whether the filesystem path s begins with the
+// elements in prefix.
+func hasFilePathPrefix(s, prefix string) bool {
+	sv := strings.ToUpper(filepath.VolumeName(s))
+	pv := strings.ToUpper(filepath.VolumeName(prefix))
+	s = s[len(sv):]
+	prefix = prefix[len(pv):]
+	switch {
+	default:
+		return false
+	case sv != pv:
+		return false
+	case len(s) == len(prefix):
+		return s == prefix
+	case len(s) > len(prefix):
+		if prefix != "" && prefix[len(prefix)-1] == filepath.Separator {
+			return strings.HasPrefix(s, prefix)
+		}
+		return s[len(prefix)] == filepath.Separator && s[:len(prefix)] == prefix
+	}
+}
+
+// treeCanMatchPattern(pattern)(name) reports whether
+// name or children of name can possibly match pattern.
+// Pattern is the same limited glob accepted by matchPattern.
+func treeCanMatchPattern(pattern string) func(name string) bool {
+	wildCard := false
+	if i := strings.Index(pattern, "..."); i >= 0 {
+		wildCard = true
+		pattern = pattern[:i]
+	}
+	return func(name string) bool {
+		return len(name) <= len(pattern) && hasPathPrefix(pattern, name) ||
+			wildCard && strings.HasPrefix(name, pattern)
+	}
+}
+
+var isDirCache = map[string]bool{}
+
+func isDir(path string) bool {
+	result, ok := isDirCache[path]
+	if ok {
+		return result
+	}
+
+	fi, err := os.Stat(path)
+	result = err == nil && fi.IsDir()
+	isDirCache[path] = result
+	return result
+}
+
+type Package struct {
+	Root       string
+	Dir        string
+	ImportPath string
+}
+
+func ImportFile(fileName string) *Package {
+	return ImportDir(filepath.Dir(fileName))
+}
+
+func ImportDir(dir string) *Package {
+	pkg, err := build.ImportDir(dir, build.FindOnly)
+	if err != nil {
+		return &Package{"", dir, ""}
+	}
+	return &Package{pkg.Root, pkg.Dir, pkg.ImportPath}
+}
+
+// expandPath returns the symlink-expanded form of path.
+func expandPath(p string) string {
+	x, err := filepath.EvalSymlinks(p)
+	if err == nil {
+		return x
+	}
+	return p
+}
+
+// vendoredImportPath returns the expansion of path when it appears in parent.
+// If parent is x/y/z, then path might expand to x/y/z/vendor/path, x/y/vendor/path,
+// x/vendor/path, vendor/path, or else stay path if none of those exist.
+// vendoredImportPath returns the expanded path or, if no expansion is found, the original.
+func VendoredImportPath(parent *Package, path string) (found string) {
+	if parent == nil || parent.Root == "" {
+		return path
+	}
+
+	dir := filepath.Clean(parent.Dir)
+	root := filepath.Join(parent.Root, "src")
+	if !hasFilePathPrefix(dir, root) {
+		// Look for symlinks before reporting error.
+		dir = expandPath(dir)
+		root = expandPath(root)
+	}
+	if !hasFilePathPrefix(dir, root) || len(dir) <= len(root) || dir[len(root)] != filepath.Separator {
+		log.Println("invalid vendoredImportPath: dir=%q root=%q separator=%q", dir, root, string(filepath.Separator))
+		return ""
+	}
+
+	vpath := "vendor/" + path
+	for i := len(dir); i >= len(root); i-- {
+		if i < len(dir) && dir[i] != filepath.Separator {
+			continue
+		}
+		// Note: checking for the vendor directory before checking
+		// for the vendor/path directory helps us hit the
+		// isDir cache more often. It also helps us prepare a more useful
+		// list of places we looked, to report when an import is not found.
+		if !isDir(filepath.Join(dir[:i], "vendor")) {
+			continue
+		}
+		targ := filepath.Join(dir[:i], vpath)
+		if isDir(targ) && hasGoFiles(targ) {
+			importPath := parent.ImportPath
+			if importPath == "command-line-arguments" {
+				// If parent.ImportPath is 'command-line-arguments'.
+				// set to relative directory to root (also chopped root directory)
+				importPath = dir[len(root)+1:]
+			}
+			// We started with parent's dir c:\gopath\src\foo\bar\baz\quux\xyzzy.
+			// We know the import path for parent's dir.
+			// We chopped off some number of path elements and
+			// added vendor\path to produce c:\gopath\src\foo\bar\baz\vendor\path.
+			// Now we want to know the import path for that directory.
+			// Construct it by chopping the same number of path elements
+			// (actually the same number of bytes) from parent's import path
+			// and then append /vendor/path.
+			chopped := len(dir) - i
+			if chopped == len(importPath)+1 {
+				// We walked up from c:\gopath\src\foo\bar
+				// and found c:\gopath\src\vendor\path.
+				// We chopped \foo\bar (length 8) but the import path is "foo/bar" (length 7).
+				// Use "vendor/path" without any prefix.
+				return vpath
+			}
+			return importPath[:len(importPath)-chopped] + "/" + vpath
+		}
+	}
+	return path
+}
+
+// hasGoFiles reports whether dir contains any files with names ending in .go.
+// For a vendor check we must exclude directories that contain no .go files.
+// Otherwise it is not possible to vendor just a/b/c and still import the
+// non-vendored a/b. See golang.org/issue/13832.
+func hasGoFiles(dir string) bool {
+	fis, _ := ioutil.ReadDir(dir)
+	for _, fi := range fis {
+		if !fi.IsDir() && strings.HasSuffix(fi.Name(), ".go") {
+			return true
+		}
+	}
+	return false
+}
+
+// findVendor looks for the last non-terminating "vendor" path element in the given import path.
+// If there isn't one, findVendor returns ok=false.
+// Otherwise, findVendor returns ok=true and the index of the "vendor".
+//
+// Note that terminating "vendor" elements don't count: "x/vendor" is its own package,
+// not the vendored copy of an import "" (the empty import path).
+// This will allow people to have packages or commands named vendor.
+// This may help reduce breakage, or it may just be confusing. We'll see.
+func findVendor(path string) (index int, ok bool) {
+	// Two cases, depending on internal at start of string or not.
+	// The order matters: we must return the index of the final element,
+	// because the final one is where the effective import path starts.
+	switch {
+	case strings.Contains(path, "/vendor/"):
+		return strings.LastIndex(path, "/vendor/") + 1, true
+	case strings.HasPrefix(path, "vendor/"):
+		return 0, true
+	}
+	return 0, false
+}
+
+func VendorPathToImportPath(path string) string {
+	if i, ok := findVendor(path); ok {
+		return path[i+len("vendor/"):]
+	}
+	return path
+}

vendor/github.com/visualfc/gotools/stdlib/mkpkglist.go

@@ -8,11 +8,6 @@ import (
 )
 
 var pkgList = `
-cmd/cgo
-cmd/fix
-cmd/go
-cmd/gofmt
-cmd/yacc
 archive/tar
 archive/zip
 bufio
@@ -25,6 +20,7 @@ compress/zlib
 container/heap
 container/list
 container/ring
+context
 crypto
 crypto/aes
 crypto/cipher
@@ -51,6 +47,7 @@ debug/elf
 debug/gosym
 debug/macho
 debug/pe
+debug/plan9obj
 encoding
 encoding/ascii85
 encoding/asn1
@@ -69,12 +66,15 @@ flag
 fmt
 go/ast
 go/build
+go/constant
 go/doc
 go/format
+go/importer
 go/parser
 go/printer
 go/scanner
 go/token
+go/types
 hash
 hash/adler32
 hash/crc32
@@ -96,16 +96,19 @@ log
 log/syslog
 math
 math/big
+math/bits
 math/cmplx
 math/rand
 mime
 mime/multipart
+mime/quotedprintable
 net
 net/http
 net/http/cgi
 net/http/cookiejar
 net/http/fcgi
 net/http/httptest
+net/http/httptrace
 net/http/httputil
 net/http/pprof
 net/mail
@@ -120,6 +123,7 @@ os/signal
 os/user
 path
 path/filepath
+plugin
 reflect
 regexp
 regexp/syntax
@@ -128,6 +132,7 @@ runtime/cgo
 runtime/debug
 runtime/pprof
 runtime/race
+runtime/trace
 sort
 strconv
 strings

vendor/github.com/visualfc/gotools/stdlib/mkstdlib.go

@@ -11,6 +11,7 @@ import (
 	"fmt"
 	"go/format"
 	"io"
+	"io/ioutil"
 	"log"
 	"os"
 	"path"
@@ -40,13 +41,19 @@ func main() {
 		fmt.Fprintf(&buf, format, args...)
 	}
 	outf("// AUTO-GENERATED BY mkstdlib.go\n\n")
-	outf("package imports\n")
+	outf("package stdlib\n")
-	outf("var stdlib = map[string]string{\n")
+	outf("var Symbols = map[string]string{\n")
 	f := io.MultiReader(
 		mustOpen(api("go1.txt")),
 		mustOpen(api("go1.1.txt")),
 		mustOpen(api("go1.2.txt")),
 		mustOpen(api("go1.3.txt")),
+		mustOpen(api("go1.4.txt")),
+		mustOpen(api("go1.5.txt")),
+		mustOpen(api("go1.6.txt")),
+		mustOpen(api("go1.7.txt")),
+		mustOpen(api("go1.8.txt")),
+		mustOpen(api("go1.9.txt")),
 	)
 	sc := bufio.NewScanner(f)
 	fullImport := map[string]string{} // "zip.NewReader" => "archive/zip"
@@ -87,5 +94,6 @@ func main() {
 	if err != nil {
 		log.Fatal(err)
 	}
-	os.Stdout.Write(fmtbuf)
+	//os.Stdout.Write(fmtbuf)
+	ioutil.WriteFile("./zstdlib.go", fmtbuf, 0777)
 }

vendor/github.com/visualfc/gotools/stdlib/pkglist.go

@@ -1,41 +1,42 @@
 package stdlib
 
 var Packages = []string{
-	"cmd/cgo", "cmd/fix", "cmd/go", "cmd/gofmt",
+	"archive/tar", "archive/zip", "bufio", "bytes",
-	"cmd/yacc", "archive/tar", "archive/zip", "bufio",
+	"compress/bzip2", "compress/flate", "compress/gzip", "compress/lzw",
-	"bytes", "compress/bzip2", "compress/flate", "compress/gzip",
+	"compress/zlib", "container/heap", "container/list", "container/ring",
-	"compress/lzw", "compress/zlib", "container/heap", "container/list",
+	"context", "crypto", "crypto/aes", "crypto/cipher",
-	"container/ring", "crypto", "crypto/aes", "crypto/cipher",
 	"crypto/des", "crypto/dsa", "crypto/ecdsa", "crypto/elliptic",
 	"crypto/hmac", "crypto/md5", "crypto/rand", "crypto/rc4",
 	"crypto/rsa", "crypto/sha1", "crypto/sha256", "crypto/sha512",
 	"crypto/subtle", "crypto/tls", "crypto/x509", "crypto/x509/pkix",
 	"database/sql", "database/sql/driver", "debug/dwarf", "debug/elf",
-	"debug/gosym", "debug/macho", "debug/pe", "encoding",
+	"debug/gosym", "debug/macho", "debug/pe", "debug/plan9obj",
-	"encoding/ascii85", "encoding/asn1", "encoding/base32", "encoding/base64",
+	"encoding", "encoding/ascii85", "encoding/asn1", "encoding/base32",
-	"encoding/binary", "encoding/csv", "encoding/gob", "encoding/hex",
+	"encoding/base64", "encoding/binary", "encoding/csv", "encoding/gob",
-	"encoding/json", "encoding/pem", "encoding/xml", "errors",
+	"encoding/hex", "encoding/json", "encoding/pem", "encoding/xml",
-	"expvar", "flag", "fmt", "go/ast",
+	"errors", "expvar", "flag", "fmt",
-	"go/build", "go/doc", "go/format", "go/parser",
+	"go/ast", "go/build", "go/constant", "go/doc",
-	"go/printer", "go/scanner", "go/token", "hash",
+	"go/format", "go/importer", "go/parser", "go/printer",
+	"go/scanner", "go/token", "go/types", "hash",
 	"hash/adler32", "hash/crc32", "hash/crc64", "hash/fnv",
 	"html", "html/template", "image", "image/color",
 	"image/color/palette", "image/draw", "image/gif", "image/jpeg",
 	"image/png", "index/suffixarray", "io", "io/ioutil",
 	"log", "log/syslog", "math", "math/big",
-	"math/cmplx", "math/rand", "mime", "mime/multipart",
+	"math/bits", "math/cmplx", "math/rand", "mime",
-	"net", "net/http", "net/http/cgi", "net/http/cookiejar",
+	"mime/multipart", "mime/quotedprintable", "net", "net/http",
-	"net/http/fcgi", "net/http/httptest", "net/http/httputil", "net/http/pprof",
+	"net/http/cgi", "net/http/cookiejar", "net/http/fcgi", "net/http/httptest",
-	"net/mail", "net/rpc", "net/rpc/jsonrpc", "net/smtp",
+	"net/http/httptrace", "net/http/httputil", "net/http/pprof", "net/mail",
-	"net/textproto", "net/url", "os", "os/exec",
+	"net/rpc", "net/rpc/jsonrpc", "net/smtp", "net/textproto",
-	"os/signal", "os/user", "path", "path/filepath",
+	"net/url", "os", "os/exec", "os/signal",
+	"os/user", "path", "path/filepath", "plugin",
 	"reflect", "regexp", "regexp/syntax", "runtime",
 	"runtime/cgo", "runtime/debug", "runtime/pprof", "runtime/race",
-	"sort", "strconv", "strings", "sync",
+	"runtime/trace", "sort", "strconv", "strings",
-	"sync/atomic", "syscall", "testing", "testing/iotest",
+	"sync", "sync/atomic", "syscall", "testing",
-	"testing/quick", "text/scanner", "text/tabwriter", "text/template",
+	"testing/iotest", "testing/quick", "text/scanner", "text/tabwriter",
-	"text/template/parse", "time", "unicode", "unicode/utf16",
+	"text/template", "text/template/parse", "time", "unicode",
-	"unicode/utf8", "unsafe",
+	"unicode/utf16", "unicode/utf8", "unsafe",
 }
 
 func IsStdPkg(pkg string) bool {

vendor/github.com/visualfc/gotools/types/types.go

@@ -9,9 +9,11 @@ import (
 	"fmt"
 	"go/ast"
 	"go/build"
+	"go/importer"
 	"go/parser"
 	"go/printer"
 	"go/token"
+	"go/types"
 	"io/ioutil"
 	"log"
 	"os"
@@ -23,10 +25,9 @@ import (
 	"time"
 
 	"github.com/visualfc/gotools/command"
+	"github.com/visualfc/gotools/pkgutil"
 	"github.com/visualfc/gotools/stdlib"
 	"golang.org/x/tools/go/buildutil"
-	"golang.org/x/tools/go/gcimporter"
-	"golang.org/x/tools/go/types"
 )
 
 var Command = &command.Command{
@@ -46,6 +47,8 @@ var (
 	typesFindUseAll  bool
 	typesFindInfo    bool
 	typesFindDoc     bool
+	typesTags        string
+	typesTagList     = []string{} // exploded version of tags flag; set in main
 )
 
 //func init
@@ -59,6 +62,7 @@ func init() {
 	Command.Flag.BoolVar(&typesFindUse, "use", false, "find cursor usages")
 	Command.Flag.BoolVar(&typesFindUseAll, "all", false, "find cursor all usages in GOPATH")
 	Command.Flag.BoolVar(&typesFindDoc, "doc", false, "find cursor def doc")
+	Command.Flag.StringVar(&typesTags, "tags", "", "space-separated list of build tags to apply when parsing")
 }
 
 type ObjKind int
@@ -77,13 +81,17 @@ const (
 	ObjLabel
 	ObjBuiltin
 	ObjNil
+	ObjImplicit
+	ObjUnknown
+	ObjComment
 )
 
 var ObjKindName = []string{"none", "package",
 	"type", "interface", "struct",
 	"const", "var", "field",
 	"func", "method",
-	"label", "builtin", "nil"}
+	"label", "builtin", "nil",
+	"implicit", "unknown", "comment"}
 
 func (k ObjKind) String() string {
 	if k >= 0 && int(k) < len(ObjKindName) {
@@ -93,22 +101,25 @@ func (k ObjKind) String() string {
 }
 
 var builtinInfoMap = map[string]string{
-	"append":  "func append(slice []Type, elems ...Type) []Type",
+	"append":   "func append(slice []Type, elems ...Type) []Type",
-	"copy":    "func copy(dst, src []Type) int",
+	"copy":     "func copy(dst, src []Type) int",
-	"delete":  "func delete(m map[Type]Type1, key Type)",
+	"delete":   "func delete(m map[Type]Type1, key Type)",
-	"len":     "func len(v Type) int",
+	"len":      "func len(v Type) int",
-	"cap":     "func cap(v Type) int",
+	"cap":      "func cap(v Type) int",
-	"make":    "func make(Type, size IntegerType) Type",
+	"make":     "func make(Type, size IntegerType) Type",
-	"new":     "func new(Type) *Type",
+	"new":      "func new(Type) *Type",
-	"complex": "func complex(r, i FloatType) ComplexType",
+	"complex":  "func complex(r, i FloatType) ComplexType",
-	"real":    "func real(c ComplexType) FloatType",
+	"real":     "func real(c ComplexType) FloatType",
-	"imag":    "func imag(c ComplexType) FloatType",
+	"imag":     "func imag(c ComplexType) FloatType",
-	"close":   "func close(c chan<- Type)",
+	"close":    "func close(c chan<- Type)",
-	"panic":   "func panic(v interface{})",
+	"panic":    "func panic(v interface{})",
-	"recover": "func recover() interface{}",
+	"recover":  "func recover() interface{}",
-	"print":   "func print(args ...Type)",
+	"print":    "func print(args ...Type)",
-	"println": "func println(args ...Type)",
+	"println":  "func println(args ...Type)",
-	"error":   "type error interface {Error() string}",
+	"error":    "type error interface {Error() string}",
+	"Sizeof":   "func unsafe.Sizeof(any) uintptr",
+	"Offsetof": "func unsafe.Offsetof(any) uintptr",
+	"Alignof":  "func unsafe.Alignof(any) uintptr",
 }
 
 func builtinInfo(id string) string {
@@ -119,10 +130,14 @@ func builtinInfo(id string) string {
 }
 
 func simpleObjInfo(obj types.Object) string {
+	s := obj.String()
 	pkg := obj.Pkg()
-	s := simpleType(obj.String())
+	if pkg != nil {
-	if pkg != nil && pkg.Name() == "main" {
+		s = strings.Replace(s, pkg.Path(), pkg.Name(), -1)
-		return strings.Replace(s, simpleType(pkg.Path())+".", "", -1)
+		s = simpleType(s)
+		if pkg.Name() == "main" {
+			s = strings.Replace(s, "main.", "", -1)
+		}
 	}
 	return s
 }
@@ -152,7 +167,11 @@ func runTypes(cmd *command.Command, args []string) error {
 			log.Println("time", time.Now().Sub(now))
 		}()
 	}
-	w := NewPkgWalker(&build.Default)
+	typesTagList = strings.Split(typesTags, " ")
+	context := build.Default
+	context.BuildTags = append(typesTagList, context.BuildTags...)
+
+	w := NewPkgWalker(&context)
 	var cursor *FileCursor
 	if typesFilePos != "" {
 		var cursorInfo FileCursor
@@ -171,6 +190,7 @@ func runTypes(cmd *command.Command, args []string) error {
 		}
 		cursor = &cursorInfo
 	}
+	w.cursor = cursor
 	for _, pkgName := range args {
 		if pkgName == "." {
 			pkgPath, err := os.Getwd()
@@ -181,6 +201,7 @@ func runTypes(cmd *command.Command, args []string) error {
 		}
 		conf := &PkgConfig{IgnoreFuncBodies: true, AllowBinary: true, WithTestFiles: true}
 		if cursor != nil {
+			cursor.pkgName = pkgName
 			conf.Cursor = cursor
 			conf.IgnoreFuncBodies = false
 			conf.Info = &types.Info{
@@ -209,7 +230,7 @@ func runTypes(cmd *command.Command, args []string) error {
 }
 
 type FileCursor struct {
-	pkg       string
+	pkgName   string
 	fileName  string
 	fileDir   string
 	cursorPos int
@@ -228,7 +249,6 @@ type PkgConfig struct {
 	Info             *types.Info
 	XInfo            *types.Info
 	Files            map[string]*ast.File
-	TestFiles        map[string]*ast.File
 	XTestFiles       map[string]*ast.File
 }
 
@@ -237,8 +257,9 @@ func NewPkgWalker(context *build.Context) *PkgWalker {
 		context:         context,
 		fset:            token.NewFileSet(),
 		parsedFileCache: map[string]*ast.File{},
+		importingName:   map[string]bool{},
 		imported:        map[string]*types.Package{"unsafe": types.Unsafe},
-		gcimporter:      map[string]*types.Package{"unsafe": types.Unsafe},
+		gcimported:      importer.Default(),
 	}
 }
 
@@ -246,10 +267,12 @@ type PkgWalker struct {
 	fset            *token.FileSet
 	context         *build.Context
 	current         *types.Package
-	importing       types.Package
+	importingName   map[string]bool
 	parsedFileCache map[string]*ast.File
 	imported        map[string]*types.Package // packages already imported
-	gcimporter      map[string]*types.Package
+	gcimported      types.Importer
+	cursor          *FileCursor
+	//importing       types.Package
 }
 
 func contains(list []string, s string) bool {
@@ -283,19 +306,25 @@ func (w *PkgWalker) Import(parentDir string, name string, conf *PkgConfig) (pkg
 		}
 	}()
 
-	if strings.HasPrefix(name, ".") && parentDir != "" {
+	if parentDir != "" {
-		name = filepath.Join(parentDir, name)
+		if strings.HasPrefix(name, ".") {
+			name = filepath.Join(parentDir, name)
+		} else if pkgutil.IsVendorExperiment() {
+			parentPkg := pkgutil.ImportDir(parentDir)
+			name = pkgutil.VendoredImportPath(parentPkg, name)
+		}
 	}
+
 	pkg = w.imported[name]
 	if pkg != nil {
-		if pkg == &w.importing {
+		//		if pkg == &w.importing {
-			return nil, fmt.Errorf("cycle importing package %q", name)
+		//			return nil, fmt.Errorf("cycle importing package %q", name)
-		}
+		//		}
 		return pkg, nil
 	}
 
 	if typesVerbose {
-		log.Println("parser pkg", name)
+		log.Println("parser pkg", parentDir, name)
 	}
 
 	bp, err := w.importPath(name, 0)
@@ -311,33 +340,70 @@ func (w *PkgWalker) Import(parentDir string, name string, conf *PkgConfig) (pkg
 		checkName = bp.ImportPath
 	}
 
-	if err != nil {
+	if w.importingName[checkName] {
-		return nil, err
+		return nil, fmt.Errorf("cycle importing package %q", name)
-		//if _, nogo := err.(*build.NoGoError); nogo {
-		//	return
-		//}
-		//return
-		//log.Fatalf("pkg %q, dir %q: ScanDir: %v", name, info.Dir, err)
 	}
 
-	filenames := append(append([]string{}, bp.GoFiles...), bp.CgoFiles...)
+	w.importingName[checkName] = true
+
+	//	if err != nil {
+	//		return nil, err
+	//		//if _, nogo := err.(*build.NoGoError); nogo {
+	//		//	return
+	//		//}
+	//		//return
+	//		//log.Fatalf("pkg %q, dir %q: ScanDir: %v", name, info.Dir, err)
+	//	}
+
+	GoFiles := append(append([]string{}, bp.GoFiles...), bp.CgoFiles...)
+	XTestFiles := append([]string{}, bp.XTestGoFiles...)
+
 	if conf.WithTestFiles {
-		filenames = append(filenames, bp.TestGoFiles...)
+		GoFiles = append(GoFiles, bp.TestGoFiles...)
 	}
 
 	if name == "runtime" {
 		n := fmt.Sprintf("zgoos_%s.go", w.context.GOOS)
-		if !contains(filenames, n) {
+		if !contains(GoFiles, n) {
-			filenames = append(filenames, n)
+			GoFiles = append(GoFiles, n)
 		}
 
 		n = fmt.Sprintf("zgoarch_%s.go", w.context.GOARCH)
-		if !contains(filenames, n) {
+		if !contains(GoFiles, n) {
-			filenames = append(filenames, n)
+			GoFiles = append(GoFiles, n)
 		}
 	}
 
-	parserFiles := func(filenames []string, cursor *FileCursor, xtest bool) (files []*ast.File) {
+	if conf.Cursor != nil && conf.Cursor.fileName != "" {
+		cursor := conf.Cursor
+		f, _ := w.parseFileEx(bp.Dir, cursor.fileName, cursor.src, true)
+		if f != nil {
+			cursor.pos = token.Pos(w.fset.File(f.Pos()).Base()) + token.Pos(cursor.cursorPos)
+			cursor.fileDir = bp.Dir
+			isTest := strings.HasSuffix(cursor.fileName, "_test.go")
+			isXTest := false
+			if isTest && strings.HasSuffix(f.Name.Name, "_test") {
+				isXTest = true
+			}
+			cursor.xtest = isXTest
+			checkAppend := func(filenames []string, file string) []string {
+				for _, f := range filenames {
+					if f == file {
+						return filenames
+					}
+				}
+				return append(filenames, file)
+			}
+			if isXTest {
+				XTestFiles = checkAppend(XTestFiles, cursor.fileName)
+			} else {
+				GoFiles = checkAppend(GoFiles, cursor.fileName)
+			}
+		}
+	}
+
+	parserFiles := func(filenames []string, cursor *FileCursor, xtest bool) (files []*ast.File, fileMap map[string]*ast.File) {
+		fileMap = make(map[string]*ast.File)
 		for _, file := range filenames {
 			var f *ast.File
 			if cursor != nil && cursor.fileName == file {
@@ -352,33 +418,19 @@ func (w *PkgWalker) Import(parentDir string, name string, conf *PkgConfig) (pkg
 				log.Printf("error parsing package %s: %s\n", name, err)
 			}
 			files = append(files, f)
+			fileMap[file] = f
 		}
 		return
 	}
-	files := parserFiles(filenames, conf.Cursor, false)
+	var files []*ast.File
-	xfiles := parserFiles(bp.XTestGoFiles, conf.Cursor, true)
+	var xfiles []*ast.File
+	files, conf.Files = parserFiles(GoFiles, conf.Cursor, false)
+	xfiles, conf.XTestFiles = parserFiles(bp.XTestGoFiles, conf.Cursor, true)
 
 	typesConf := types.Config{
 		IgnoreFuncBodies: conf.IgnoreFuncBodies,
 		FakeImportC:      true,
-		Packages:         w.gcimporter,
+		Importer:         &Importer{w, conf, bp.Dir},
-		Import: func(imports map[string]*types.Package, name string) (pkg *types.Package, err error) {
-			if pkg != nil {
-				return pkg, nil
-			}
-			if conf.AllowBinary && w.isBinaryPkg(name) {
-				pkg = w.gcimporter[name]
-				if pkg != nil && pkg.Complete() {
-					return
-				}
-				pkg, err = gcimporter.Import(imports, name)
-				if pkg != nil && pkg.Complete() {
-					w.gcimporter[name] = pkg
-					return
-				}
-			}
-			return w.Import(bp.Dir, name, &PkgConfig{IgnoreFuncBodies: true, AllowBinary: true, WithTestFiles: false})
-		},
 		Error: func(err error) {
 			if typesVerbose {
 				log.Println(err)
@@ -389,6 +441,7 @@ func (w *PkgWalker) Import(parentDir string, name string, conf *PkgConfig) (pkg
 		pkg, err = typesConf.Check(checkName, w.fset, files, conf.Info)
 		conf.Pkg = pkg
 	}
+	w.importingName[checkName] = false
 	w.imported[name] = pkg
 
 	if len(xfiles) > 0 {
@@ -399,7 +452,36 @@ func (w *PkgWalker) Import(parentDir string, name string, conf *PkgConfig) (pkg
 	return
 }
 
+type Importer struct {
+	w    *PkgWalker
+	conf *PkgConfig
+	dir  string
+}
+
+func (im *Importer) Import(name string) (pkg *types.Package, err error) {
+	if im.conf.AllowBinary && im.w.isBinaryPkg(name) {
+		pkg, err = im.w.gcimported.Import(name)
+		if pkg != nil && pkg.Complete() {
+			return
+		}
+		//		pkg = im.w.gcimporter[name]
+		//		if pkg != nil && pkg.Complete() {
+		//			return
+		//		}
+		//		pkg, err = importer.Default().Import(name)
+		//		if pkg != nil && pkg.Complete() {
+		//			im.w.gcimporter[name] = pkg
+		//			return
+		//		}
+	}
+	return im.w.Import(im.dir, name, &PkgConfig{IgnoreFuncBodies: true, AllowBinary: true, WithTestFiles: false})
+}
+
 func (w *PkgWalker) parseFile(dir, file string, src interface{}) (*ast.File, error) {
+	return w.parseFileEx(dir, file, src, typesFindDoc)
+}
+
+func (w *PkgWalker) parseFileEx(dir, file string, src interface{}, findDoc bool) (*ast.File, error) {
 	filename := filepath.Join(dir, file)
 	f, _ := w.parsedFileCache[filename]
 	if f != nil {
@@ -427,7 +509,7 @@ func (w *PkgWalker) parseFile(dir, file string, src interface{}) (*ast.File, err
 
 	if f == nil {
 		flag := parser.AllErrors
-		if typesFindDoc {
+		if findDoc {
 			flag |= parser.ParseComments
 		}
 		f, err = parser.ParseFile(w.fset, filename, src, flag)
@@ -441,8 +523,9 @@ func (w *PkgWalker) parseFile(dir, file string, src interface{}) (*ast.File, err
 }
 
 func (w *PkgWalker) LookupCursor(pkg *types.Package, conf *PkgConfig, cursor *FileCursor) {
-	is := w.CheckIsImport(cursor)
+	if nm := w.CheckIsName(cursor); nm != nil {
-	if is != nil {
+		w.LookupName(pkg, conf, cursor, nm)
+	} else if is := w.CheckIsImport(cursor); is != nil {
 		if cursor.xtest {
 			w.LookupImport(conf.XPkg, conf.XInfo, cursor, is)
 		} else {
@@ -453,6 +536,44 @@ func (w *PkgWalker) LookupCursor(pkg *types.Package, conf *PkgConfig, cursor *Fi
 	}
 }
 
+func (w *PkgWalker) LookupName(pkg *types.Package, conf *PkgConfig, cursor *FileCursor, nm *ast.Ident) {
+	if typesFindDef {
+		fmt.Println(w.fset.Position(nm.Pos()))
+	}
+	if typesFindInfo {
+		if cursor.xtest {
+			fmt.Printf("package %s (%q)\n", pkg.Name()+"_test", pkg.Path())
+		} else {
+			if pkg.Path() == pkg.Name() {
+				fmt.Printf("package %s\n", pkg.Name())
+			} else {
+				fmt.Printf("package %s (%q)\n", pkg.Name(), pkg.Path())
+			}
+		}
+	}
+
+	if !typesFindUse {
+		return
+	}
+	var usages []int
+	findUsage := func(fileMap map[string]*ast.File) {
+		for _, f := range fileMap {
+			if f != nil && f.Name != nil && f.Name.Name == nm.Name {
+				usages = append(usages, int(f.Name.Pos()))
+			}
+		}
+	}
+	if cursor.xtest {
+		findUsage(conf.XTestFiles)
+	} else {
+		findUsage(conf.Files)
+	}
+	(sort.IntSlice(usages)).Sort()
+	for _, pos := range usages {
+		fmt.Println(w.fset.Position(token.Pos(pos)))
+	}
+}
+
 func (w *PkgWalker) LookupImport(pkg *types.Package, pkgInfo *types.Info, cursor *FileCursor, is *ast.ImportSpec) {
 	fpath, err := strconv.Unquote(is.Path.Value)
 	if err != nil {
@@ -480,7 +601,7 @@ func (w *PkgWalker) LookupImport(pkg *types.Package, pkgInfo *types.Info, cursor
 		if fname == fpath {
 			fmt.Printf("package %s\n", fname)
 		} else {
-			fmt.Printf("package %s (\"%s\")\n", fname, fpath)
+			fmt.Printf("package %s (%q)\n", fname, fpath)
 		}
 	}
 
@@ -489,10 +610,13 @@ func (w *PkgWalker) LookupImport(pkg *types.Package, pkgInfo *types.Info, cursor
 	}
 
 	fid := pkg.Path() + "." + fname
+
 	var usages []int
 	for id, obj := range pkgInfo.Uses {
 		if obj != nil && obj.Id() == fid { //!= nil && cursorObj.Pos() == obj.Pos() {
-			usages = append(usages, int(id.Pos()))
+			if _, ok := obj.(*types.PkgName); ok {
+				usages = append(usages, int(id.Pos()))
+			}
 		}
 	}
 	(sort.IntSlice(usages)).Sort()
@@ -501,6 +625,14 @@ func (w *PkgWalker) LookupImport(pkg *types.Package, pkgInfo *types.Info, cursor
 	}
 }
 
+func testObjKind(obj types.Object, kind ObjKind) bool {
+	k, err := parserObjKind(obj)
+	if err != nil {
+		return false
+	}
+	return k == kind
+}
+
 func parserObjKind(obj types.Object) (ObjKind, error) {
 	var kind ObjKind
 	switch t := obj.(type) {
@@ -662,6 +794,14 @@ func IsSameObject(a, b types.Object) bool {
 	if a.Id() != b.Id() {
 		return false
 	}
+	if a.Type().String() != b.Type().String() {
+		return false
+	}
+	t1, ok1 := a.(*types.TypeName)
+	t2, ok2 := b.(*types.TypeName)
+	if ok1 && ok2 {
+		return t1.Type().String() == t2.Type().String()
+	}
 	return a.String() == b.String()
 }
 
@@ -698,10 +838,12 @@ func (w *PkgWalker) LookupObjects(conf *PkgConfig, cursor *FileCursor) {
 			}
 		}
 	}
+	var cursorId *ast.Ident
 	if cursorObj == nil {
 		for id, obj := range pkgInfo.Defs {
 			if cursor.pos >= id.Pos() && cursor.pos <= id.End() {
 				cursorObj = obj
+				cursorId = id
 				cursorObjIsDef = true
 				break
 			}
@@ -716,13 +858,19 @@ func (w *PkgWalker) LookupObjects(conf *PkgConfig, cursor *FileCursor) {
 			}
 		}
 	}
-	if cursorObj == nil {
+
+	var kind ObjKind
+	if cursorObj != nil {
+		var err error
+		kind, err = parserObjKind(cursorObj)
+		if err != nil {
+			log.Fatalln(err)
+		}
+	} else if cursorId != nil {
+		kind = ObjImplicit
+	} else {
 		return
 	}
-	kind, err := parserObjKind(cursorObj)
-	if err != nil {
-		log.Fatalln(err)
-	}
 
 	if kind == ObjField {
 		if cursorObj.(*types.Var).Anonymous() {
@@ -732,8 +880,18 @@ func (w *PkgWalker) LookupObjects(conf *PkgConfig, cursor *FileCursor) {
 			}
 		}
 	}
-	cursorPkg := cursorObj.Pkg()
+
-	cursorPos := cursorObj.Pos()
+	var cursorPkg *types.Package
+	var cursorPos token.Pos
+
+	if cursorObj != nil {
+		cursorPkg = cursorObj.Pkg()
+		cursorPos = cursorObj.Pos()
+	} else {
+		cursorPkg = pkg
+		cursorPos = cursorId.Pos()
+	}
+
 	//var fieldTypeInfo *types.Info
 	var fieldTypeObj types.Object
 	//	if cursorPkg == pkg {
@@ -741,6 +899,8 @@ func (w *PkgWalker) LookupObjects(conf *PkgConfig, cursor *FileCursor) {
 	//	}
 	cursorIsInterfaceMethod := false
 	var cursorInterfaceTypeName string
+	var cursorInterfaceTypeNamed *types.Named
+
 	if kind == ObjMethod && cursorSelection != nil && cursorSelection.Recv() != nil {
 		sig := cursorObj.(*types.Func).Type().Underlying().(*types.Signature)
 		if _, ok := sig.Recv().Type().Underlying().(*types.Interface); ok {
@@ -754,6 +914,7 @@ func (w *PkgWalker) LookupObjects(conf *PkgConfig, cursor *FileCursor) {
 					cursorInterfaceTypeName = typ.Obj().Name()
 				}
 				cursorIsInterfaceMethod = true
+				cursorInterfaceTypeNamed = named
 			}
 		}
 	} else if kind == ObjField && cursorSelection != nil {
@@ -770,6 +931,9 @@ func (w *PkgWalker) LookupObjects(conf *PkgConfig, cursor *FileCursor) {
 			}
 		}
 	}
+	if typesVerbose {
+		log.Println("parser", cursorObj, kind, cursorIsInterfaceMethod)
+	}
 	if cursorPkg != nil && cursorPkg != pkg &&
 		kind != ObjPkgName && w.isBinaryPkg(cursorPkg.Path()) {
 		conf := &PkgConfig{
@@ -783,23 +947,41 @@ func (w *PkgWalker) LookupObjects(conf *PkgConfig, cursor *FileCursor) {
 		pkg, _ := w.Import("", cursorPkg.Path(), conf)
 		if pkg != nil {
 			if cursorIsInterfaceMethod {
-				for _, obj := range conf.Info.Defs {
+				for k, v := range conf.Info.Defs {
-					if obj == nil {
+					if k != nil && v != nil && IsSameObject(v, cursorInterfaceTypeNamed.Obj()) {
-						continue
+						named := v.Type().(*types.Named)
-					}
+						obj, typ := w.lookupNamedMethod(named, cursorObj.Name())
-					if fn, ok := obj.(*types.Func); ok {
+						if obj != nil {
-						if fn.Name() == cursorObj.Name() {
+							cursorObj = obj
-							if sig, ok := fn.Type().Underlying().(*types.Signature); ok {
+							cursorPos = obj.Pos()
-								if named, ok := sig.Recv().Type().(*types.Named); ok {
-									if named.Obj() != nil && named.Obj().Name() == cursorInterfaceTypeName {
-										cursorPos = obj.Pos()
-										break
-									}
-								}
-							}
 						}
+						if obj != nil {
+							cursorObj = obj
+						}
+						if typ != nil {
+							cursorPkg = typ.Obj().Pkg()
+							cursorInterfaceTypeName = typ.Obj().Name()
+						}
+						break
 					}
 				}
+				//				for _, obj := range conf.Info.Defs {
+				//					if obj == nil {
+				//						continue
+				//					}
+				//					if fn, ok := obj.(*types.Func); ok {
+				//						if fn.Name() == cursorObj.Name() {
+				//							if sig, ok := fn.Type().Underlying().(*types.Signature); ok {
+				//								if named, ok := sig.Recv().Type().(*types.Named); ok {
+				//									if named.Obj() != nil && named.Obj().Name() == cursorInterfaceTypeName {
+				//										cursorPos = obj.Pos()
+				//										break
+				//									}
+				//								}
+				//							}
+				//						}
+				//					}
+				//				}
 			} else if kind == ObjField && fieldTypeObj != nil {
 				for _, obj := range conf.Info.Defs {
 					if obj == nil {
@@ -839,16 +1021,19 @@ func (w *PkgWalker) LookupObjects(conf *PkgConfig, cursor *FileCursor) {
 		fmt.Println(w.fset.Position(cursorPos))
 	}
 	if typesFindInfo {
-		if kind == ObjField && fieldTypeObj != nil {
+		/*if kind == ObjField && fieldTypeObj != nil {
 			typeName := fieldTypeObj.Name()
 			if fieldTypeObj.Pkg() != nil && fieldTypeObj.Pkg() != pkg {
 				typeName = fieldTypeObj.Pkg().Name() + "." + fieldTypeObj.Name()
 			}
 			fmt.Println(typeName, simpleObjInfo(cursorObj))
-		} else if kind == ObjBuiltin {
+		} else */
+		if kind == ObjBuiltin {
 			fmt.Println(builtinInfo(cursorObj.Name()))
 		} else if kind == ObjPkgName {
 			fmt.Println(cursorObj.String())
+		} else if kind == ObjImplicit {
+			fmt.Printf("%s is implicit\n", cursorId.Name)
 		} else if cursorIsInterfaceMethod {
 			fmt.Println(strings.Replace(simpleObjInfo(cursorObj), "(interface)", cursorPkg.Name()+"."+cursorInterfaceTypeName, 1))
 		} else {
@@ -883,7 +1068,9 @@ func (w *PkgWalker) LookupObjects(conf *PkgConfig, cursor *FileCursor) {
 	if kind == ObjPkgName {
 		for id, obj := range pkgInfo.Uses {
 			if obj != nil && obj.Id() == cursorObj.Id() { //!= nil && cursorObj.Pos() == obj.Pos() {
-				usages = append(usages, int(id.Pos()))
+				if _, ok := obj.(*types.PkgName); ok {
+					usages = append(usages, int(id.Pos()))
+				}
 			}
 		}
 	} else {
@@ -892,9 +1079,17 @@ func (w *PkgWalker) LookupObjects(conf *PkgConfig, cursor *FileCursor) {
 		//				usages = append(usages, int(id.Pos()))
 		//			}
 		//		}
-		for id, obj := range pkgInfo.Uses {
+		if cursorObj != nil {
-			if obj == cursorObj { //!= nil && cursorObj.Pos() == obj.Pos() {
+			for id, obj := range pkgInfo.Uses {
-				usages = append(usages, int(id.Pos()))
+				if obj == cursorObj { //!= nil && cursorObj.Pos() == obj.Pos() {
+					usages = append(usages, int(id.Pos()))
+				}
+			}
+		} else {
+			for id, obj := range pkgInfo.Uses {
+				if obj != nil && obj.Pos() == cursorPos { //!= nil && cursorObj.Pos() == obj.Pos() {
+					usages = append(usages, int(id.Pos()))
+				}
 			}
 		}
 	}
@@ -907,8 +1102,9 @@ func (w *PkgWalker) LookupObjects(conf *PkgConfig, cursor *FileCursor) {
 		xpkg_path = conf.XPkg.Path()
 	}
 
-	if cursorPkg != nil && (cursorPkg.Path() == pkg_path ||
+	if cursorPkg != nil &&
-		cursorPkg.Path() == xpkg_path) {
+		(cursorPkg.Path() == pkg_path || cursorPkg.Path() == xpkg_path) &&
+		kind != ObjPkgName {
 		usages = append(usages, int(cursorPos))
 	}
 
@@ -957,7 +1153,12 @@ func (w *PkgWalker) LookupObjects(conf *PkgConfig, cursor *FileCursor) {
 		uses_paths = append(uses_paths, cursorPkg.Path())
 	}
 
-	buildutil.ForEachPackage(&build.Default, func(importPath string, err error) {
+	cursorPkgPath := cursorObj.Pkg().Path()
+	if pkgutil.IsVendorExperiment() {
+		cursorPkgPath = pkgutil.VendorPathToImportPath(cursorPkgPath)
+	}
+
+	buildutil.ForEachPackage(w.context, func(importPath string, err error) {
 		if err != nil {
 			return
 		}
@@ -973,7 +1174,7 @@ func (w *PkgWalker) LookupObjects(conf *PkgConfig, cursor *FileCursor) {
 			find = true
 		} else {
 			for _, v := range bp.Imports {
-				if v == cursorObj.Pkg().Path() {
+				if v == cursorPkgPath {
 					find = true
 					break
 				}
@@ -1031,6 +1232,20 @@ func (w *PkgWalker) LookupObjects(conf *PkgConfig, cursor *FileCursor) {
 	}
 }
 
+func (w *PkgWalker) CheckIsName(cursor *FileCursor) *ast.Ident {
+	if cursor.fileDir == "" {
+		return nil
+	}
+	file, _ := w.parseFile(cursor.fileDir, cursor.fileName, cursor.src)
+	if file == nil {
+		return nil
+	}
+	if inRange(file.Name, cursor.pos) {
+		return file.Name
+	}
+	return nil
+}
+
 func (w *PkgWalker) CheckIsImport(cursor *FileCursor) *ast.ImportSpec {
 	if cursor.fileDir == "" {
 		return nil

vendor/vendor.json

@@ -5,8 +5,8 @@
 		{
 			"checksumSHA1": "ZesPb1w0u5/uv/fdVc+G6wOee30=",
 			"path": "github.com/b3log/wide",
-			"revision": "0a51a03f35a3fa9edbfa790698aa615f4dd49783",
+			"revision": "0b8da631759171441b7c46b78151fbf6345d5bb8",
-			"revisionTime": "2018-03-13T05:05:45Z"
+			"revisionTime": "2018-03-13T05:11:10Z"
 		},
 		{
 			"checksumSHA1": "83iEp3SqOoIkZUYyR7BOVP4vaGE=",
@@ -71,10 +71,10 @@
 			"revisionTime": "2018-02-17T01:27:43Z"
 		},
 		{
-			"checksumSHA1": "QBwzyczN2ftqO2Vxag5TS79q32E=",
+			"checksumSHA1": "h9/MfYdq0vlJ5n/MszzARxhAY88=",
 			"path": "github.com/visualfc/gotools/astview",
-			"revision": "b8348693492ca3791bccfa028f3c19634c11c5b5",
+			"revision": "a74583d2ad8773983f273657291df981033308a4",
-			"revisionTime": "2015-04-09T14:25:36Z"
+			"revisionTime": "2018-02-17T01:27:43Z"
 		},
 		{
 			"checksumSHA1": "02f7N5GTTddWpIDhsRthRKZs4nI=",
@@ -85,8 +85,8 @@
 		{
 			"checksumSHA1": "sA2FN414rFhNEgac/a0IyUR8dMA=",
 			"path": "github.com/visualfc/gotools/docview",
-			"revision": "b8348693492ca3791bccfa028f3c19634c11c5b5",
+			"revision": "a74583d2ad8773983f273657291df981033308a4",
-			"revisionTime": "2015-04-09T14:25:36Z"
+			"revisionTime": "2018-02-17T01:27:43Z"
 		},
 		{
 			"checksumSHA1": "5sCU5oJIkeXHHhzNyzusSH+de/8=",
@@ -95,16 +95,16 @@
 			"revisionTime": "2018-02-17T01:27:43Z"
 		},
 		{
-			"checksumSHA1": "LvxdwB9kJ77cFS4qiRAh9ts2nz4=",
+			"checksumSHA1": "HmZqKNWLGAznshKi6RaoNCfUiX4=",
 			"path": "github.com/visualfc/gotools/finddoc",
-			"revision": "b8348693492ca3791bccfa028f3c19634c11c5b5",
+			"revision": "a74583d2ad8773983f273657291df981033308a4",
-			"revisionTime": "2015-04-09T14:25:36Z"
+			"revisionTime": "2018-02-17T01:27:43Z"
 		},
 		{
 			"checksumSHA1": "Sxih6vWVTlJNBdVNeyCkxI213yI=",
 			"path": "github.com/visualfc/gotools/goapi",
-			"revision": "b8348693492ca3791bccfa028f3c19634c11c5b5",
+			"revision": "a74583d2ad8773983f273657291df981033308a4",
-			"revisionTime": "2015-04-09T14:25:36Z"
+			"revisionTime": "2018-02-17T01:27:43Z"
 		},
 		{
 			"checksumSHA1": "o0usAkdrTaqufvGTZu++Cc/DVMM=",
@@ -127,8 +127,8 @@
 		{
 			"checksumSHA1": "R6+qmg1mEs4XhihZd5ujddVI+FI=",
 			"path": "github.com/visualfc/gotools/gopresent",
-			"revision": "b8348693492ca3791bccfa028f3c19634c11c5b5",
+			"revision": "a74583d2ad8773983f273657291df981033308a4",
-			"revisionTime": "2015-04-09T14:25:36Z"
+			"revisionTime": "2018-02-17T01:27:43Z"
 		},
 		{
 			"checksumSHA1": "f8zd5auG22z/GqXqW9giRDYEw6A=",
@@ -139,32 +139,50 @@
 		{
 			"checksumSHA1": "kyKBo2ux+HflucDj/qzoko5YoMA=",
 			"path": "github.com/visualfc/gotools/jsonfmt",
-			"revision": "b8348693492ca3791bccfa028f3c19634c11c5b5",
+			"revision": "a74583d2ad8773983f273657291df981033308a4",
-			"revisionTime": "2015-04-09T14:25:36Z"
+			"revisionTime": "2018-02-17T01:27:43Z"
 		},
 		{
-			"checksumSHA1": "QldbuEtO8CONs3q/5mkva+CVeNg=",
+			"checksumSHA1": "1B56213xrQhxQG1+ZILXNK6cuoo=",
 			"path": "github.com/visualfc/gotools/oracle",
-			"revision": "b8348693492ca3791bccfa028f3c19634c11c5b5",
+			"revision": "a74583d2ad8773983f273657291df981033308a4",
-			"revisionTime": "2015-04-09T14:25:36Z"
+			"revisionTime": "2018-02-17T01:27:43Z"
 		},
 		{
-			"checksumSHA1": "zG4ar8LbudIKQvsfvAgkBSS0k3Q=",
+			"checksumSHA1": "YwA6y+SSXb/JiRGCNowOTrxzP5c=",
+			"path": "github.com/visualfc/gotools/oracle/oracle",
+			"revision": "a74583d2ad8773983f273657291df981033308a4",
+			"revisionTime": "2018-02-17T01:27:43Z"
+		},
+		{
+			"checksumSHA1": "QlJ4yti//o5hoD6w8J6UgLeWjHI=",
+			"path": "github.com/visualfc/gotools/oracle/oracle/serial",
+			"revision": "a74583d2ad8773983f273657291df981033308a4",
+			"revisionTime": "2018-02-17T01:27:43Z"
+		},
+		{
+			"checksumSHA1": "rPh1Qefw9BjwxY/jcpXWePPwYCU=",
 			"path": "github.com/visualfc/gotools/pkgs",
-			"revision": "b8348693492ca3791bccfa028f3c19634c11c5b5",
+			"revision": "a74583d2ad8773983f273657291df981033308a4",
-			"revisionTime": "2015-04-09T14:25:36Z"
+			"revisionTime": "2018-02-17T01:27:43Z"
+		},
+		{
+			"checksumSHA1": "dnnib3Gp6gDR8f1HSd4q2DENHiM=",
+			"path": "github.com/visualfc/gotools/pkgutil",
+			"revision": "a74583d2ad8773983f273657291df981033308a4",
+			"revisionTime": "2018-02-17T01:27:43Z"
 		},
 		{
 			"checksumSHA1": "RQoGIbxntMsUZvi4Js0WQqDBDYM=",
 			"path": "github.com/visualfc/gotools/runcmd",
-			"revision": "b8348693492ca3791bccfa028f3c19634c11c5b5",
+			"revision": "a74583d2ad8773983f273657291df981033308a4",
-			"revisionTime": "2015-04-09T14:25:36Z"
+			"revisionTime": "2018-02-17T01:27:43Z"
 		},
 		{
-			"checksumSHA1": "q/EpLJHMTcnbxjLGogryQ6IA7kc=",
+			"checksumSHA1": "nQZTp19L2U+0vVarHKt+3PcsrJM=",
 			"path": "github.com/visualfc/gotools/stdlib",
-			"revision": "b8348693492ca3791bccfa028f3c19634c11c5b5",
+			"revision": "a74583d2ad8773983f273657291df981033308a4",
-			"revisionTime": "2015-04-09T14:25:36Z"
+			"revisionTime": "2018-02-17T01:27:43Z"
 		},
 		{
 			"checksumSHA1": "6CSw3Gtu+hJ6QTfhJ+985cualxs=",
@@ -173,10 +191,10 @@
 			"revisionTime": "2018-02-17T01:27:43Z"
 		},
 		{
-			"checksumSHA1": "qlJsyinWZ07PaOyTYyxXOmhDN/I=",
+			"checksumSHA1": "7NOVBr5xAnJIiAGOnIPCvTSxKO4=",
 			"path": "github.com/visualfc/gotools/types",
-			"revision": "b8348693492ca3791bccfa028f3c19634c11c5b5",
+			"revision": "a74583d2ad8773983f273657291df981033308a4",
-			"revisionTime": "2015-04-09T14:25:36Z"
+			"revisionTime": "2018-02-17T01:27:43Z"
 		},
 		{
 			"checksumSHA1": "xe5hMqClV1HmKZ4GVg4bmSsVRE8=",