blob: 78bba644f5bb1010b61ee3be67235258fb9bc0b6 [file] [log] [blame]
// 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:convert';
import 'dart:io';
import 'package:args/args.dart';
import 'package:file/file.dart';
import 'package:file/local.dart';
import 'package:package_config/package_config.dart';
import 'package:path/path.dart' as path;
import 'package:vm_snapshot_analysis/program_info.dart';
import 'package:vm_snapshot_analysis/v8_profile.dart';
const FileSystem fs = LocalFileSystem();
Future<void> main(List<String> args) async {
final Options options = Options.fromArgs(args);
final String json = options.snapshot.readAsStringSync();
final Snapshot snapshot = Snapshot.fromJson(jsonDecode(json) as Map<String, dynamic>);
final ProgramInfo programInfo = toProgramInfo(snapshot);
final List<String> foundForbiddenTypes = <String>[];
bool fail = false;
for (final String forbiddenType in options.forbiddenTypes) {
final int slash = forbiddenType.indexOf('/');
final int doubleColons = forbiddenType.indexOf('::');
if (slash == -1 || doubleColons < 2) {
print('Invalid forbidden type "$forbiddenType". The format must be <package_uri>::<type_name>, e.g. package:flutter/src/widgets/framework.dart::Widget');
fail = true;
if (!await validateType(forbiddenType, options.packageConfig)) {
foundForbiddenTypes.add('Forbidden type "$forbiddenType" does not seem to exist.');
final List<String> lookupPath = <String>[
forbiddenType.substring(0, slash),
forbiddenType.substring(0, doubleColons),
forbiddenType.substring(doubleColons + 2),
if (programInfo.lookup(lookupPath) != null) {
if (fail) {
print('Invalid forbidden type formats. Exiting.');
if (foundForbiddenTypes.isNotEmpty) {
print('The output contained the following forbidden types:');
print('No forbidden types found.');
Future<bool> validateType(String forbiddenType, File packageConfigFile) async {
if (!forbiddenType.startsWith('package:')) {
print('Warning: Unable to validate $forbiddenType. Continuing.');
return true;
final Uri packageUri = Uri.parse(forbiddenType.substring(0, forbiddenType.indexOf('::')));
final String typeName = forbiddenType.substring(forbiddenType.indexOf('::') + 2);
final PackageConfig packageConfig = PackageConfig.parseString(
final Uri? packageFileUri = packageConfig.resolve(packageUri);
final File packageFile = fs.file(packageFileUri);
if (!packageFile.existsSync()) {
print('File $packageFile does not exist - forbidden type has moved or been removed.');
return false;
// This logic is imperfect. It will not detect mixed in types the way that
// the snapshot has them, e.g. TypeName&MixedIn&Whatever. It also assumes
// there is at least one space before and after the type name, which is not
// strictly required by the language.
final List<String> contents = packageFile.readAsStringSync().split('\n');
for (final String line in contents) {
// Ignore comments.
// This will fail for multi- and intra-line comments (i.e. /* */).
if (line.trim().startsWith('//')) {
if (line.contains(' $typeName ')) {
return true;
return false;
class Options {
const Options({
required this.snapshot,
required this.packageConfig,
required this.forbiddenTypes,
factory Options.fromArgs(List<String> args) {
final ArgParser argParser = ArgParser();
help: 'The path V8 snapshot file.',
valueHelp: '/tmp/snapshot.arm64-v8a.json',
help: 'Dart package_config.json file generated by `pub get`.',
valueHelp: path.join(r'$FLUTTER_ROOT', 'examples', 'hello_world', '.dart_tool', 'package_config.json'),
defaultsTo: path.join(fs.currentDirectory.path, 'examples', 'hello_world', '.dart_tool', 'package_config.json'),
help: 'Type name(s) to forbid from release compilation, e.g. "package:flutter/src/widgets/framework.dart::Widget".',
valueHelp: '<package_uri>::<type_name>',
argParser.addFlag('help', help: 'Prints usage.', negatable: false);
final ArgResults argResults = argParser.parse(args);
if (argResults['help'] == true) {
return Options(
snapshot: _getFileArg(argResults, 'snapshot'),
packageConfig: _getFileArg(argResults, 'package-config'),
forbiddenTypes: Set<String>.from(argResults['forbidden-type'] as List<String>),
final File snapshot;
final File packageConfig;
final Set<String> forbiddenTypes;
static File _getFileArg(ArgResults argResults, String argName) {
final File result = fs.file(argResults[argName] as String);
if (!result.existsSync()) {
print('The $argName file at $result could not be found.');
return result;