Script to find Flutter earliest Flutter revision that contains an engine revision (#50948)
diff --git a/dev/tools/find_engine_commit.dart b/dev/tools/find_engine_commit.dart
new file mode 100644
index 0000000..8b87553
--- /dev/null
+++ b/dev/tools/find_engine_commit.dart
@@ -0,0 +1,130 @@
+// Copyright 2014 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'dart:io';
+
+void _validate(List<String> args) {
+ bool errors = false;
+ if (!File('bin/internal/engine.version').existsSync()) {
+ errors = true;
+ print('This program must be run from the root of your flutter repository.');
+ }
+ if (!File('../engine/src/flutter/DEPS').existsSync()) {
+ errors = true;
+ print('This program assumes the engine directory is a sibling to the flutter repository directory.');
+ }
+ if (args.length != 1) {
+ errors = true;
+ print('This program takes the engine revision as a single argument.');
+ }
+ if (errors) {
+ exit(-1);
+ }
+}
+
+const String engineRepo = '../engine/src/flutter';
+
+Future<void> main(List<String> args) async {
+ _validate(args);
+ await _fetchUpstream();
+ await _fetchUpstream(engineRepo);
+ String flutterRevision;
+ await for (final FlutterEngineRevision revision in _logEngineVersions()) {
+ if (!await containsRevision(args[0], revision.engineRevision)) {
+ if (flutterRevision == null) {
+ print('Revision not found.');
+ exit(-1);
+ }
+ print('earliest revision: $flutterRevision');
+ print('Tags that contain this engine revision:');
+ print(await _tagsForRevision(flutterRevision));
+ exit(0);
+ }
+ flutterRevision = revision.flutterRevision;
+ }
+}
+
+Future<void> _fetchUpstream([String workingDirectory = '.']) async {
+ print('Fetching remotes for "$workingDirectory" - you may be prompted for SSH credentials by git.');
+ final ProcessResult fetchResult = await Process.run(
+ 'git',
+ <String>[
+ 'fetch',
+ '--all',
+ ],
+ workingDirectory: workingDirectory,
+ );
+ if (fetchResult.exitCode != 0) {
+ throw Exception('Failed to fetch upstream in repository $workingDirectory');
+ }
+}
+
+Future<String> _tagsForRevision(String flutterRevision) async {
+ final ProcessResult tagResult = await Process.run(
+ 'git',
+ <String>[
+ 'tag',
+ '--contains',
+ flutterRevision,
+ ],
+ );
+ return tagResult.stdout as String;
+}
+
+Future<bool> containsRevision(String ancestorRevision, String revision) async {
+ final ProcessResult result = await Process.run(
+ 'git',
+ <String>[
+ 'merge-base',
+ '--is-ancestor',
+ ancestorRevision,
+ revision,
+ ],
+ workingDirectory: engineRepo,
+ );
+ return result.exitCode == 0;
+}
+
+Stream<FlutterEngineRevision> _logEngineVersions() async* {
+ final ProcessResult result = await Process.run(
+ 'git',
+ <String>[
+ 'log',
+ '--oneline',
+ '-p',
+ '--',
+ 'bin/internal/engine.version',
+ ],
+ );
+ if (result.exitCode != 0) {
+ print(result.stderr);
+ throw Exception('Failed to log bin/internal/engine.version');
+ }
+
+ final List<String> lines = (result.stdout as String).split('\n');
+ int index = 0;
+ while (index < lines.length - 1) {
+ final String flutterRevision = lines[index].split(' ').first;
+ index += 1;
+ while (!lines[index].startsWith('+') || lines[index].startsWith('+++')) {
+ index += 1;
+ }
+ if (index >= lines.length) {
+ break;
+ }
+ final String engineRevision = lines[index].substring(1);
+ yield FlutterEngineRevision(flutterRevision, engineRevision);
+ index += lines[index + 1].startsWith(r'\ ') ? 2 : 1;
+ }
+}
+
+class FlutterEngineRevision {
+ const FlutterEngineRevision(this.flutterRevision, this.engineRevision);
+
+ final String flutterRevision;
+ final String engineRevision;
+
+ @override
+ String toString() => '$flutterRevision: $engineRevision';
+}
