blob: 93a832eb0e291055e77dd38c01f078646c09f6dd [file] [log] [blame]
// Copyright 2013 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 'package:file/file.dart';
import 'package:git/git.dart';
import 'package:path/path.dart' as p;
import 'package:platform/platform.dart';
import 'package:pub_semver/pub_semver.dart';
import 'common/core.dart';
import 'common/file_utils.dart';
import 'common/git_version_finder.dart';
import 'common/package_looping_command.dart';
import 'common/plugin_utils.dart';
import 'common/process_runner.dart';
import 'common/repository_package.dart';
/// A command to check that PRs don't violate repository best practices that
/// have been established to avoid breakages that building and testing won't
/// catch.
class FederationSafetyCheckCommand extends PackageLoopingCommand {
/// Creates an instance of the safety check command.
Directory packagesDir, {
ProcessRunner processRunner = const ProcessRunner(),
Platform platform = const LocalPlatform(),
GitDir? gitDir,
}) : super(
processRunner: processRunner,
platform: platform,
gitDir: gitDir,
// A map of package name (as defined by the directory name of the package)
// to a list of changed Dart files in that package, as Posix paths relative to
// the package root.
// This only considers top-level packages, not subpackages such as example/.
final Map<String, List<String>> _changedDartFiles = <String, List<String>>{};
// The set of *_platform_interface packages that will have public code changes
// published.
final Set<String> _modifiedAndPublishedPlatformInterfacePackages = <String>{};
// The set of conceptual plugins (not packages) that have changes.
final Set<String> _changedPlugins = <String>{};
static const String _platformInterfaceSuffix = '_platform_interface';
final String name = 'federation-safety-check';
final String description =
'Checks that the change does not violate repository rules around changes '
'to federated plugin packages.';
bool get hasLongOutput => false;
Future<void> initializeRun() async {
final GitVersionFinder gitVersionFinder = await retrieveVersionFinder();
final String baseSha = await gitVersionFinder.getBaseSha();
print('Validating changes relative to "$baseSha"\n');
for (final String path in await gitVersionFinder.getChangedFiles()) {
// Git output always uses Posix paths.
final List<String> allComponents = p.posix.split(path);
final int packageIndex = allComponents.indexOf('packages');
if (packageIndex == -1) {
final List<String> relativeComponents =
allComponents.sublist(packageIndex + 1);
// The package name is either the directory directly under packages/, or
// the directory under that in the case of a federated plugin.
String packageName = relativeComponents.removeAt(0);
// Count the top-level plugin as changed.
if (relativeComponents[0] == packageName ||
(relativeComponents.length > 1 &&
relativeComponents[0].startsWith('${packageName}_'))) {
packageName = relativeComponents.removeAt(0);
if (relativeComponents.last.endsWith('.dart')) {
_changedDartFiles[packageName] ??= <String>[];
if (packageName.endsWith(_platformInterfaceSuffix) &&
relativeComponents.first == 'pubspec.yaml' &&
await _packageWillBePublished(path)) {
Future<PackageResult> runForPackage(RepositoryPackage package) async {
if (!isFlutterPlugin(package)) {
return PackageResult.skip('Not a plugin.');
if (!package.isFederated) {
return PackageResult.skip('Not a federated plugin.');
if (package.isPlatformInterface) {
// As the leaf nodes in the graph, a published package interface change is
// assumed to be correct, and other changes are validated against that.
return PackageResult.skip(
'Platform interface changes are not validated.');
// Uses basename to match _changedPackageFiles.
final String basePackageName =;
final String platformInterfacePackageName =
final List<String> changedPlatformInterfaceFiles =
_changedDartFiles[platformInterfacePackageName] ?? <String>[];
if (!_modifiedAndPublishedPlatformInterfacePackages
.contains(platformInterfacePackageName)) {
print('No published changes for $platformInterfacePackageName.');
return PackageResult.success();
if (!changedPlatformInterfaceFiles
.any((String path) => path.startsWith('lib/'))) {
print('No public code changes for $platformInterfacePackageName.');
return PackageResult.success();
final List<String> changedPackageFiles =
_changedDartFiles[] ?? <String>[];
if (changedPackageFiles.isEmpty) {
print('No Dart changes.');
return PackageResult.success();
// If the change would be flagged, but it appears to be a mass change
// rather than a plugin-specific change, allow it with a warning.
// This is a tradeoff between safety and convenience; forcing mass changes
// to be split apart is not ideal, and the assumption is that reviewers are
// unlikely to accidentally approve a PR that is supposed to be changing a
// single plugin, but touches other plugins (vs accidentally approving a
// PR that changes multiple parts of a single plugin, which is a relatively
// easy mistake to make).
// 3 is chosen to minimize the chances of accidentally letting something
// through (vs 2, which could be a single-plugin change with one stray
// change to another file accidentally included), while not setting too
// high a bar for detecting mass changes. This can be tuned if there are
// issues with false positives or false negatives.
const int massChangePluginThreshold = 3;
if (_changedPlugins.length >= massChangePluginThreshold) {
logWarning('Ignoring potentially dangerous change, as this appears '
'to be a mass change.');
return PackageResult.success();
printError('Dart changes are not allowed to other packages in '
'$basePackageName in the same PR as changes to public Dart code in '
'$platformInterfacePackageName, as this can cause accidental breaking '
'changes to be missed by automated checks. Please split the changes to '
'these two packages into separate PRs.\n\n'
'If you believe that this is a false positive, please file a bug.');
<String>['$platformInterfacePackageName changed.']);
Future<bool> _packageWillBePublished(
String pubspecRepoRelativePosixPath) async {
final File pubspecFile = childFileWithSubcomponents(
packagesDir.parent, p.posix.split(pubspecRepoRelativePosixPath));
if (!pubspecFile.existsSync()) {
// If the package was deleted, nothing will be published.
return false;
final Pubspec pubspec = Pubspec.parse(pubspecFile.readAsStringSync());
if (pubspec.publishTo == 'none') {
return false;
final GitVersionFinder gitVersionFinder = await retrieveVersionFinder();
final Version? previousVersion =
await gitVersionFinder.getPackageVersion(pubspecRepoRelativePosixPath);
if (previousVersion == null) {
// The plugin is new, so it will be published.
return true;
return pubspec.version != previousVersion;