From 891de38080f27011cb050301c7948b52e3141470 Mon Sep 17 00:00:00 2001
From: Joas Schilling <coding@schilljs.com>
Date: Thu, 19 Jul 2018 15:32:36 +0200
Subject: [PATCH] Only create the schema when moving between databases

Signed-off-by: Joas Schilling <coding@schilljs.com>
---
 core/Command/Db/ConvertType.php     |  2 +-
 lib/private/DB/MigrationService.php | 24 +++++++++++++++---------
 2 files changed, 16 insertions(+), 10 deletions(-)

diff --git a/core/Command/Db/ConvertType.php b/core/Command/Db/ConvertType.php
index 7fdf1f39b8..b6c2c66b3d 100644
--- a/core/Command/Db/ConvertType.php
+++ b/core/Command/Db/ConvertType.php
@@ -245,7 +245,7 @@ class ConvertType extends Command implements CompletionAwareInterface {
 				$currentMigration = $fromMS->getMigration('current');
 				if ($currentMigration !== '0') {
 					$toMS = new MigrationService($app, $toDB);
-					$toMS->migrate($currentMigration);
+					$toMS->migrate($currentMigration, true);
 				}
 			}
 		}
diff --git a/lib/private/DB/MigrationService.php b/lib/private/DB/MigrationService.php
index cc2889dae0..6f5a74103a 100644
--- a/lib/private/DB/MigrationService.php
+++ b/lib/private/DB/MigrationService.php
@@ -376,13 +376,14 @@ class MigrationService {
 	 * Applies all not yet applied versions up to $to
 	 *
 	 * @param string $to
+	 * @param bool $schemaOnly
 	 * @throws \InvalidArgumentException
 	 */
-	public function migrate($to = 'latest') {
+	public function migrate($to = 'latest', $schemaOnly = false) {
 		// read known migrations
 		$toBeExecuted = $this->getMigrationsToExecute($to);
 		foreach ($toBeExecuted as $version) {
-			$this->executeStep($version);
+			$this->executeStep($version, $schemaOnly);
 		}
 	}
 
@@ -432,14 +433,17 @@ class MigrationService {
 	 * Executes one explicit version
 	 *
 	 * @param string $version
+	 * @param bool $schemaOnly
 	 * @throws \InvalidArgumentException
 	 */
-	public function executeStep($version) {
+	public function executeStep($version, $schemaOnly = false) {
 		$instance = $this->createInstance($version);
 
-		$instance->preSchemaChange($this->output, function() {
-			return new SchemaWrapper($this->connection);
-		}, ['tablePrefix' => $this->connection->getPrefix()]);
+		if (!$schemaOnly) {
+			$instance->preSchemaChange($this->output, function() {
+				return new SchemaWrapper($this->connection);
+			}, ['tablePrefix' => $this->connection->getPrefix()]);
+		}
 
 		$toSchema = $instance->changeSchema($this->output, function() {
 			return new SchemaWrapper($this->connection);
@@ -450,9 +454,11 @@ class MigrationService {
 			$toSchema->performDropTableCalls();
 		}
 
-		$instance->postSchemaChange($this->output, function() {
-			return new SchemaWrapper($this->connection);
-		}, ['tablePrefix' => $this->connection->getPrefix()]);
+		if (!$schemaOnly) {
+			$instance->postSchemaChange($this->output, function() {
+				return new SchemaWrapper($this->connection);
+			}, ['tablePrefix' => $this->connection->getPrefix()]);
+		}
 
 		$this->markAsExecuted($version);
 	}