Merge branch 'development'

CHANGELOG.md

@@ -13,7 +13,7 @@ GRDB adheres to [Semantic Versioning](https://semver.org/), with one exception:
 
 #### 4.x Releases
 
-- `4.12.x` Releases - [4.12.0](#4120)
+- `4.12.x` Releases - [4.12.0](#4120) | [4.12.1](#4121)
 - `4.11.x` Releases - [4.11.0](#4110)
 - `4.10.x` Releases - [4.10.0](#4100)
 - `4.9.x` Releases - [4.9.0](#490)
@@ -69,6 +69,15 @@ GRDB adheres to [Semantic Versioning](https://semver.org/), with one exception:
 ## Next Release
 -->
 
+## 4.12.1
+
+Released March 29, 2020 • [diff](https://github.com/groue/GRDB.swift/compare/v4.12.0...v4.12.1)
+
+**Fixed**
+
+- [#744](https://github.com/groue/GRDB.swift/pull/744): Fix DatabaseMigrator deadlock with serial target queues
+
+
 ## 4.12.0
 
 Released March 21, 2020 • [diff](https://github.com/groue/GRDB.swift/compare/v4.11.0...v4.12.0)

GRDB.swift.podspec

@@ -1,6 +1,6 @@
 Pod::Spec.new do |s|
   s.name     = 'GRDB.swift'
-  s.version  = '4.12.0'
+  s.version  = '4.12.1'
 
   s.license  = { :type => 'MIT', :file => 'LICENSE' }
   s.summary  = 'A toolkit for SQLite databases, with a focus on application development.'

GRDB/Migration/DatabaseMigrator.swift

@@ -160,7 +160,9 @@ public struct DatabaseMigrator {
                         //
                         // Create a temporary witness database (on disk, just in case
                         // migrations would involve a lot of data).
-                        let witness = try DatabaseQueue(path: "", configuration: writer.configuration)
+                        var witnessConfiguration = writer.configuration
+                        witnessConfiguration.targetQueue = nil // Avoid deadlocks
+                        let witness = try DatabaseQueue(path: "", configuration: witnessConfiguration)
 
                         // Grab schema of migrated witness database
                         let witnessSchema: SchemaInfo = try witness.writeWithoutTransaction { db in

Makefile

@@ -466,8 +466,8 @@ ifdef JAZZY
 	  --author 'Gwendal Roué' \
 	  --author_url https://github.com/groue \
 	  --github_url https://github.com/groue/GRDB.swift \
-	  --github-file-prefix https://github.com/groue/GRDB.swift/tree/v4.12.0 \
-	  --module-version 4.12.0 \
+	  --github-file-prefix https://github.com/groue/GRDB.swift/tree/v4.12.1 \
+	  --module-version 4.12.1 \
 	  --module GRDB \
 	  --root-url http://groue.github.io/GRDB.swift/docs/4.12/ \
 	  --output Documentation/Reference \

README.md

@@ -12,14 +12,14 @@
 
 ---
 
-**Latest release**: March 21, 2020 • version 4.12.0 • [CHANGELOG](CHANGELOG.md) • [Migrating From GRDB 3 to GRDB 4](Documentation/GRDB3MigrationGuide.md)
+**Latest release**: March 29, 2020 • version 4.12.1 • [CHANGELOG](CHANGELOG.md) • [Migrating From GRDB 3 to GRDB 4](Documentation/GRDB3MigrationGuide.md)
 
 **Requirements**: iOS 9.0+ / macOS 10.9+ / tvOS 9.0+ / watchOS 2.0+ • Swift 4.2+ / Xcode 10.0+
 
 | Swift version | GRDB version                                                |
 | ------------- | ----------------------------------------------------------- |
-| **Swift 5**   | **v4.12.0**                                                  |
-| **Swift 4.2** | **v4.12.0**                                                  |
+| **Swift 5**   | **v4.12.1**                                                  |
+| **Swift 4.2** | **v4.12.1**                                                  |
 | Swift 4.1     | [v3.7.0](https://github.com/groue/GRDB.swift/tree/v3.7.0)   |
 | Swift 4       | [v2.10.0](https://github.com/groue/GRDB.swift/tree/v2.10.0) |
 | Swift 3.2     | [v1.3.0](https://github.com/groue/GRDB.swift/tree/v1.3.0)   |

Support/Info.plist

@@ -15,7 +15,7 @@
 	<key>CFBundlePackageType</key>
 	<string>FMWK</string>
 	<key>CFBundleShortVersionString</key>
-	<string>4.12.0</string>
+	<string>4.12.1</string>
 	<key>CFBundleSignature</key>
 	<string>????</string>
 	<key>CFBundleVersion</key>

Tests/GRDBTests/DatabaseMigratorTests.swift

@@ -553,6 +553,20 @@ class DatabaseMigratorTests : GRDBTestCase {
         try XCTAssertTrue(dbQueue.read(newMigrator.hasCompletedMigrations))
     }
 
+    // Regression test for https://github.com/groue/GRDB.swift/issues/741
+    func testEraseDatabaseOnSchemaChangeDoesNotDeadLock() throws {
+        dbConfiguration.targetQueue = DispatchQueue(label: "target")
+        let dbQueue = try makeDatabaseQueue()
+
+        var migrator = DatabaseMigrator()
+        migrator.eraseDatabaseOnSchemaChange = true
+        migrator.registerMigration("1", migrate: { _ in })
+        try migrator.migrate(dbQueue)
+
+        migrator.registerMigration("2", migrate: { _ in })
+        try migrator.migrate(dbQueue)
+    }
+
     func testEraseDatabaseOnSchemaChange() throws {
         // 1st version of the migrator
         var migrator1 = DatabaseMigrator()