Update conductor to write engine.version file (#163350)

This adds a new phase to the conductor after applying cherrypicks, to
update the engine.version file with the revision from the previous
commit. Note, this will produce a different PR, because it has to be in
a different commit after squash & merge.

Automates https://github.com/flutter/flutter/issues/162265

dev/conductor/core/lib/src/next.dart

@@ -150,6 +150,51 @@ class NextContext extends Context {
           }
         }
 
+        await pushWorkingBranch(framework, state.framework);
+      case pb.ReleasePhase.UPDATE_ENGINE_VERSION:
+        final Remote upstream = Remote.upstream(state.framework.upstream.url);
+        final FrameworkRepository framework = FrameworkRepository(
+          checkouts,
+          initialRef: state.framework.workingBranch,
+          upstreamRemote: upstream,
+          previousCheckoutLocation: state.framework.checkoutPath,
+        );
+        final String rev = await framework.reverseParse('HEAD');
+        final File engineVersionFile = (await framework.checkoutDirectory)
+            .childDirectory('bin')
+            .childDirectory('internal')
+            .childFile('engine.version');
+
+        engineVersionFile.writeAsStringSync(rev);
+
+        // Must force add since it is gitignored
+        await framework.git.run(
+          const <String>['add', 'bin/internal/engine.version', '--force'],
+          'adding engine.version file',
+          workingDirectory: (await framework.checkoutDirectory).path,
+        );
+        final String revision = await framework.commit(
+          'Create engine.version file pointing to $rev',
+        );
+        // append to list of cherrypicks so we know a PR is required
+        state.framework.cherrypicks.add(
+          pb.Cherrypick.create()
+            ..appliedRevision = revision
+            ..state = pb.CherrypickState.COMPLETED,
+        );
+
+        if (!autoAccept) {
+          final bool response = await prompt(
+            'Are you ready to push your framework branch to the repository '
+            '${state.framework.mirror.url}?',
+          );
+          if (!response) {
+            stdio.printError('Aborting command.');
+            updateState(state, stdio.logs);
+            return;
+          }
+        }
+
         await pushWorkingBranch(framework, state.framework);
       case pb.ReleasePhase.PUBLISH_VERSION:
         final String command = '''

dev/conductor/core/lib/src/proto/conductor_state.pbenum.dart

@@ -20,15 +20,18 @@ import 'package:protobuf/protobuf.dart' as $pb;
 class ReleasePhase extends $pb.ProtobufEnum {
   static const ReleasePhase APPLY_FRAMEWORK_CHERRYPICKS =
       ReleasePhase._(0, _omitEnumNames ? '' : 'APPLY_FRAMEWORK_CHERRYPICKS');
+  static const ReleasePhase UPDATE_ENGINE_VERSION =
+      ReleasePhase._(1, _omitEnumNames ? '' : 'UPDATE_ENGINE_VERSION');
   static const ReleasePhase PUBLISH_VERSION =
-      ReleasePhase._(1, _omitEnumNames ? '' : 'PUBLISH_VERSION');
+      ReleasePhase._(2, _omitEnumNames ? '' : 'PUBLISH_VERSION');
   static const ReleasePhase VERIFY_RELEASE =
-      ReleasePhase._(2, _omitEnumNames ? '' : 'VERIFY_RELEASE');
+      ReleasePhase._(3, _omitEnumNames ? '' : 'VERIFY_RELEASE');
   static const ReleasePhase RELEASE_COMPLETED =
-      ReleasePhase._(3, _omitEnumNames ? '' : 'RELEASE_COMPLETED');
+      ReleasePhase._(4, _omitEnumNames ? '' : 'RELEASE_COMPLETED');
 
   static const $core.List<ReleasePhase> values = <ReleasePhase>[
     APPLY_FRAMEWORK_CHERRYPICKS,
+    UPDATE_ENGINE_VERSION,
     PUBLISH_VERSION,
     VERIFY_RELEASE,
     RELEASE_COMPLETED,

dev/conductor/core/lib/src/proto/conductor_state.pbjson.dart

@@ -22,16 +22,18 @@ const ReleasePhase$json = {
   '1': 'ReleasePhase',
   '2': [
     {'1': 'APPLY_FRAMEWORK_CHERRYPICKS', '2': 0},
-    {'1': 'PUBLISH_VERSION', '2': 1},
+    {'1': 'UPDATE_ENGINE_VERSION', '2': 1},
-    {'1': 'VERIFY_RELEASE', '2': 2},
+    {'1': 'PUBLISH_VERSION', '2': 2},
-    {'1': 'RELEASE_COMPLETED', '2': 3},
+    {'1': 'VERIFY_RELEASE', '2': 3},
+    {'1': 'RELEASE_COMPLETED', '2': 4},
   ],
 };
 
 /// Descriptor for `ReleasePhase`. Decode as a `google.protobuf.EnumDescriptorProto`.
 final $typed_data.Uint8List releasePhaseDescriptor = $convert
-    .base64Decode('CgxSZWxlYXNlUGhhc2USHwobQVBQTFlfRlJBTUVXT1JLX0NIRVJSWVBJQ0tTEAASEwoPUFVCTE'
+    .base64Decode('CgxSZWxlYXNlUGhhc2USHwobQVBQTFlfRlJBTUVXT1JLX0NIRVJSWVBJQ0tTEAASGQoVVVBEQV'
-        'lTSF9WRVJTSU9OEAESEgoOVkVSSUZZX1JFTEVBU0UQAhIVChFSRUxFQVNFX0NPTVBMRVRFRBAD');
+        'RFX0VOR0lORV9WRVJTSU9OEAESEwoPUFVCTElTSF9WRVJTSU9OEAISEgoOVkVSSUZZX1JFTEVB'
+        'U0UQAxIVChFSRUxFQVNFX0NPTVBMRVRFRBAE');
 
 @$core.Deprecated('Use cherrypickStateDescriptor instead')
 const CherrypickState$json = {

dev/conductor/core/lib/src/proto/conductor_state.proto

@@ -11,14 +11,16 @@ message Remote {
 enum ReleasePhase {
   APPLY_FRAMEWORK_CHERRYPICKS = 0;
 
+  UPDATE_ENGINE_VERSION = 1;
+
   // Git tag applied to framework RC branch HEAD and pushed upstream.
-  PUBLISH_VERSION = 1;
+  PUBLISH_VERSION = 2;
 
   // Package artifacts verified to exist on cloud storage.
-  VERIFY_RELEASE = 2;
+  VERIFY_RELEASE = 3;
 
   // There is no further work to be done.
-  RELEASE_COMPLETED = 3;
+  RELEASE_COMPLETED = 4;
 }
 
 enum CherrypickState {

dev/conductor/core/lib/src/repository.dart

@@ -411,16 +411,18 @@ abstract class Repository {
   }
 
   Future<String> commit(String message, {bool addFirst = false, String? author}) async {
-    final bool hasChanges =
-        (await git.getOutput(
-          <String>['status', '--porcelain'],
-          'check for uncommitted changes',
-          workingDirectory: (await checkoutDirectory).path,
-        )).trim().isNotEmpty;
-    if (!hasChanges) {
-      throw ConductorException('Tried to commit with message $message but no changes were present');
-    }
     if (addFirst) {
+      final bool hasChanges =
+          (await git.getOutput(
+            <String>['status', '--porcelain'],
+            'check for uncommitted changes',
+            workingDirectory: (await checkoutDirectory).path,
+          )).trim().isNotEmpty;
+      if (!hasChanges) {
+        throw ConductorException(
+          'Tried to commit with message $message but no changes were present',
+        );
+      }
       await git.run(
         <String>['add', '--all'],
         'add all changes to the index',

dev/conductor/core/lib/src/state.dart

@@ -156,6 +156,8 @@ String phaseInstructions(pb.ConductorState state) {
       return <String>[
         'Either all cherrypicks have been auto-applied or there were none.',
       ].join('\n');
+    case ReleasePhase.UPDATE_ENGINE_VERSION:
+      return 'The conductor will now update the engine.version file to point at the previous commit.';
     case ReleasePhase.PUBLISH_VERSION:
       if (!requiresFrameworkPR(state)) {
         return 'Since there are no code changes in this release, no Framework '
@@ -223,18 +225,11 @@ String githubAccount(String remoteUrl) {
 /// Will throw a [ConductorException] if [ReleasePhase.RELEASE_COMPLETED] is
 /// passed as an argument, as there is no next phase.
 ReleasePhase getNextPhase(ReleasePhase currentPhase) {
-  switch (currentPhase) {
+  final ReleasePhase? nextPhase = ReleasePhase.valueOf(currentPhase.value + 1);
-    case ReleasePhase.PUBLISH_VERSION:
+  if (nextPhase != null) {
-      return ReleasePhase.VERIFY_RELEASE;
+    return nextPhase;
-    case ReleasePhase.APPLY_FRAMEWORK_CHERRYPICKS:
-    case ReleasePhase.VERIFY_RELEASE:
-    case ReleasePhase.RELEASE_COMPLETED:
-      final ReleasePhase? nextPhase = ReleasePhase.valueOf(currentPhase.value + 1);
-      if (nextPhase != null) {
-        return nextPhase;
-      }
   }
-  throw globals.ConductorException('There is no next ReleasePhase!');
+  throw globals.ConductorException('There is no next ReleasePhase after $currentPhase!');
 }
 
 // Indent two spaces.

dev/conductor/core/test/next_test.dart

@@ -23,7 +23,7 @@ void main() {
   const String candidateBranch = 'flutter-1.2-candidate.3';
   const String workingBranch = 'cherrypicks-$candidateBranch';
   const String revision1 = 'd3af60d18e01fcb36e0c0fa06c8502e4935ed095';
-  const String revision3 = 'ffffffffffffffffffffffffffffffffffffffff';
+  const String revision2 = 'ffffffffffffffffffffffffffffffffffffffff';
   const String releaseVersion = '1.2.0-3.0.pre';
   const String releaseChannel = 'beta';
   const String stateFile = '/state-file.json';
@@ -70,7 +70,7 @@ void main() {
         );
       });
 
-      group('APPLY_FRAMEWORK_CHERRYPICKS to PUBLISH_VERSION', () {
+      group('APPLY_FRAMEWORK_CHERRYPICKS to UPDATE_ENGINE_VERSION', () {
         const String mirrorRemoteUrl = 'https://github.com/org/repo.git';
         const String upstreamRemoteUrl = 'https://github.com/mirror/repo.git';
         const String engineUpstreamRemoteUrl = 'https://github.com/mirror/engine.git';
@@ -154,7 +154,7 @@ void main() {
                 'Create candidate branch version $candidateBranch for $releaseChannel',
               ],
             ),
-            const FakeCommand(command: <String>['git', 'rev-parse', 'HEAD'], stdout: revision3),
+            const FakeCommand(command: <String>['git', 'rev-parse', 'HEAD'], stdout: revision2),
           ]);
           writeStateToFile(fileSystem.file(stateFile), state, <String>[]);
           final Checkouts checkouts = Checkouts(
@@ -207,7 +207,7 @@ void main() {
                 'Create candidate branch version $candidateBranch for $releaseChannel',
               ],
             ),
-            const FakeCommand(command: <String>['git', 'rev-parse', 'HEAD'], stdout: revision3),
+            const FakeCommand(command: <String>['git', 'rev-parse', 'HEAD'], stdout: revision2),
             const FakeCommand(
               command: <String>['git', 'push', 'mirror', 'HEAD:refs/heads/$workingBranch'],
             ),
@@ -226,7 +226,7 @@ void main() {
 
           final pb.ConductorState finalState = readStateFromFile(fileSystem.file(stateFile));
 
-          expect(finalState.currentPhase, ReleasePhase.PUBLISH_VERSION);
+          expect(finalState.currentPhase, ReleasePhase.UPDATE_ENGINE_VERSION);
           expect(stdio.stdout, contains('There was 1 cherrypick that was not auto-applied'));
           expect(
             stdio.stdout,
@@ -241,6 +241,117 @@ void main() {
           expect(stdio.error, isEmpty);
         });
       });
+      group('UPDATE_ENGINE_VERSION to PUBLISH_VERSION', () {
+        const String mirrorRemoteUrl = 'https://github.com/org/repo.git';
+        const String upstreamRemoteUrl = 'https://github.com/mirror/repo.git';
+        const String engineUpstreamRemoteUrl = 'https://github.com/mirror/engine.git';
+        const String frameworkCheckoutPath = '$checkoutsParentDirectory/framework';
+        const String engineCheckoutPath = '$checkoutsParentDirectory/engine';
+        const String oldEngineVersion = '000000001';
+
+        late FakeProcessManager processManager;
+        late FakePlatform platform;
+        late pb.ConductorState state;
+
+        setUp(() {
+          processManager = FakeProcessManager.empty();
+          platform = FakePlatform(
+            environment: <String, String>{
+              'HOME': <String>['path', 'to', 'home'].join(localPathSeparator),
+            },
+            operatingSystem: localOperatingSystem,
+            pathSeparator: localPathSeparator,
+          );
+          state =
+              (pb.ConductorState.create()
+                ..releaseChannel = releaseChannel
+                ..releaseVersion = releaseVersion
+                ..framework =
+                    (pb.Repository.create()
+                      ..candidateBranch = candidateBranch
+                      ..checkoutPath = frameworkCheckoutPath
+                      ..mirror =
+                          (pb.Remote.create()
+                            ..name = 'mirror'
+                            ..url = mirrorRemoteUrl)
+                      ..upstream =
+                          (pb.Remote.create()
+                            ..name = 'upstream'
+                            ..url = upstreamRemoteUrl)
+                      ..workingBranch = workingBranch)
+                ..engine =
+                    (pb.Repository.create()
+                      ..candidateBranch = candidateBranch
+                      ..checkoutPath = engineCheckoutPath
+                      ..dartRevision = 'cdef0123'
+                      ..workingBranch = workingBranch
+                      ..upstream =
+                          (pb.Remote.create()
+                            ..name = 'upstream'
+                            ..url = engineUpstreamRemoteUrl))
+                ..currentPhase = ReleasePhase.UPDATE_ENGINE_VERSION);
+          // create engine repo
+          fileSystem.directory(engineCheckoutPath).createSync(recursive: true);
+          // create framework repo
+          final Directory frameworkDir = fileSystem.directory(frameworkCheckoutPath);
+          final File engineRevisionFile = frameworkDir
+              .childDirectory('bin')
+              .childDirectory('internal')
+              .childFile('engine.version');
+          engineRevisionFile.createSync(recursive: true);
+          engineRevisionFile.writeAsStringSync(oldEngineVersion, flush: true);
+        });
+
+        test('creates a PR with an updated engine.version file', () async {
+          // Respond "yes" to the prompt to push branch
+          stdio.stdin.add('y');
+          processManager.addCommands(const <FakeCommand>[
+            FakeCommand(command: <String>['git', 'fetch', 'upstream']),
+            FakeCommand(command: <String>['git', 'checkout', 'cherrypicks-$candidateBranch']),
+            FakeCommand(command: <String>['git', 'rev-parse', 'HEAD'], stdout: revision1),
+            FakeCommand(command: <String>['git', 'add', 'bin/internal/engine.version', '--force']),
+            FakeCommand(
+              command: <String>[
+                'git',
+                'commit',
+                '--message',
+                'Create engine.version file pointing to $revision1',
+              ],
+            ),
+            FakeCommand(command: <String>['git', 'rev-parse', 'HEAD'], stdout: revision2),
+            FakeCommand(
+              command: <String>[
+                'git',
+                'push',
+                'mirror',
+                'HEAD:refs/heads/cherrypicks-$candidateBranch',
+              ],
+            ),
+          ]);
+          writeStateToFile(fileSystem.file(stateFile), state, <String>[]);
+          final Checkouts checkouts = Checkouts(
+            fileSystem: fileSystem,
+            parentDirectory: fileSystem.directory(checkoutsParentDirectory)
+              ..createSync(recursive: true),
+            platform: platform,
+            processManager: processManager,
+            stdio: stdio,
+          );
+
+          final CommandRunner<void> runner = createRunner(checkouts: checkouts);
+          await runner.run(<String>['next', '--$kStateOption', stateFile]);
+
+          final pb.ConductorState finalState = readStateFromFile(fileSystem.file(stateFile));
+
+          expect(finalState.currentPhase, ReleasePhase.PUBLISH_VERSION);
+          expect(
+            fileSystem
+                .file('$frameworkCheckoutPath/bin/internal/engine.version')
+                .readAsStringSync(),
+            revision1,
+          );
+        });
+      });
 
       group('PUBLISH_VERSION to VERIFY_RELEASE', () {
         const String releaseVersion = '1.2.0-3.0.pre';

dev/conductor/core/test/repository_test.dart

@@ -73,7 +73,7 @@ vars = {
       );
     });
 
-    test('commit() throws if there are no local changes to commit', () {
+    test('commit() throws if there are no local changes to commit and addFirst = true', () {
       const String commit1 = 'abc123';
       const String commit2 = 'def456';
       const String message = 'This is a commit message.';
@@ -106,7 +106,7 @@ vars = {
 
       final FrameworkRepository repo = FrameworkRepository(checkouts);
       expect(
-        () async => repo.commit(message),
+        () async => repo.commit(message, addFirst: true),
         throwsExceptionWith('Tried to commit with message $message but no changes were present'),
       );
     });
@@ -129,10 +129,6 @@ vars = {
         ),
         const FakeCommand(command: <String>['git', 'checkout', FrameworkRepository.defaultBranch]),
         const FakeCommand(command: <String>['git', 'rev-parse', 'HEAD'], stdout: commit1),
-        const FakeCommand(
-          command: <String>['git', 'status', '--porcelain'],
-          stdout: 'MM path/to/file.txt',
-        ),
         const FakeCommand(command: <String>['git', 'commit', '--message', message]),
         const FakeCommand(command: <String>['git', 'rev-parse', 'HEAD'], stdout: commit2),
       ]);