pkg/front_end/tool/trim.dart

#!/usr/bin/env dart
// Copyright (c) 2025, the Dart project authors.  Please see the AUTHORS file
// for details. 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';

import 'package:args/args.dart';
import 'package:front_end/src/util/trim.dart';
import 'package:kernel/target/targets.dart';
import 'package:vm/modular/target/flutter.dart';

/// Helper script to invoke [createTrimmedCopy] as a command-line tool given a
/// `dynamic_interface.yaml` input file.
Future<void> main(List<String> args) async {
  ArgResults argResults;
  try {
    argResults = _argParser.parse(args);
  } on ArgParserException catch (e) {
    print(e.message);
    print(_argParser.usage);
    exit(1);
  }

  if (args.length < 2) {
    print(_argParser.usage);
    exit(1);
  }
  String? dynamicInterfacePath = argResults['dynamic-interface'] as String?;
  File? dynamicInterface =
      dynamicInterfacePath != null ? File(dynamicInterfacePath) : null;
  await createTrimmedCopy(TrimOptions(
      inputAppPath: argResults['input'] as String,
      inputPlatformPath: argResults['platform'] as String,
      outputAppPath: argResults['output'] as String,
      outputPlatformPath: argResults['output-platform'] as String?,
      dynamicInterfaceUri: dynamicInterface?.uri,
      dynamicInterfaceContents: dynamicInterface?.readAsStringSync(),
      requiredUserLibraries:
          (argResults['required-user-libraries'] as List<String>).toSet(),
      requiredDartLibraries:
          FlutterTarget(TargetFlags()).extraRequiredLibraries.toSet(),
      librariesToClear:
          (argResults['clear-dart-library-body'] as List<String>).toSet()));
}

final ArgParser _argParser = ArgParser()
  ..addOption('input',
      help: 'Input application dill file path', mandatory: true)
  ..addOption('platform',
      help: 'Input platform dill file path', mandatory: true)
  ..addOption('output',
      help: 'Output application dill file path', mandatory: true)
  ..addOption('output-platform', help: 'Output platform dill file path')
  ..addOption('dynamic-interface',
      help: 'Path to the dynamic_interface.yaml file')
  ..addMultiOption('clear-dart-library-body',
      abbr: 'c',
      help: 'List of `dart:` that, even though are required, can be cleared '
          'internally since they are only included for compatibility with '
          '"extraRequiredLibraries", but are not needed for compilation',
      defaultsTo: defaultNonProductionLibraries)
  ..addMultiOption('required-user-libraries',
      abbr: 'u',
      help: 'Alternative to providing a dynamic_interface.yaml input. '
          'Specifies the list of necessary user written '
          'libraries. Can be a full `package:` URI or a prefix pattern, '
          'like `package:foo/*`.',
      defaultsTo: const []);

/// Libraries that are not needed for production builds and that should
/// be possible to clear when trimming .dill files.
const List<String> defaultNonProductionLibraries = [
  'dart:mirrors',
  'dart:developer',
  'dart:ffi',
  'dart:vmservice_io',
  'dart:isolate ',
  'dart:_vmservice',
  'dart:cli',
];