packages/flutter_tools/test/integration.shard/flutter_run_with_error_test.dart

// 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:async';

import 'package:file/file.dart';
import 'package:flutter_tools/src/base/io.dart';
import 'package:vm_service/vm_service.dart';
import 'package:vm_service/vm_service_io.dart';

import '../src/common.dart';
import 'test_data/project_with_early_error.dart';
import 'test_driver.dart';
import 'test_utils.dart';

void main() {
  late Directory tempDir;
  final ProjectWithEarlyError project = ProjectWithEarlyError();
  const String exceptionStart = '══╡ EXCEPTION CAUGHT BY WIDGETS LIBRARY ╞══════════════════';
  late FlutterRunTestDriver flutter;

  setUp(() async {
    tempDir = createResolvedTempDirectorySync('run_test.');
    await project.setUpIn(tempDir);
    flutter = FlutterRunTestDriver(tempDir);
  });

  tearDown(() async {
    tryToDelete(tempDir);
  });

  testWithoutContext('flutter run in non-machine mode reports an early error in an application', () async {
    final String flutterBin = fileSystem.path.join(
      getFlutterRoot(),
      'bin',
      'flutter',
    );

    final StringBuffer stdout = StringBuffer();

    final Process process = await processManager.start(<String>[
      flutterBin,
      'run',
      '--disable-service-auth-codes',
      '--show-test-device',
      '-dflutter-tester',
      '--start-paused',
      '--dart-define=flutter.inspector.structuredErrors=true',
    ], workingDirectory: tempDir.path);

    transformToLines(process.stdout).listen((String line) async {
      stdout.writeln(line);

      if (line.startsWith('An Observatory debugger')) {
        final RegExp exp = RegExp(r'http://127.0.0.1:(\d+)/');
        final RegExpMatch match = exp.firstMatch(line)!;
        final String port = match.group(1)!;
        if (port != null) {
          final VmService vmService =
              await vmServiceConnectUri('ws://localhost:$port/ws');
          final VM vm = await vmService.getVM();
          for (final IsolateRef isolate in vm.isolates!) {
            await vmService.resume(isolate.id!);
          }
        }
      }

      if (line.startsWith('Another exception was thrown')) {
        process.kill();
      }
    });

    await process.exitCode;

    expect(stdout.toString(), contains(exceptionStart));
  });

  testWithoutContext('flutter run in machine mode does not print an error', () async {
    final StringBuffer stdout = StringBuffer();

    await flutter.run(
      startPaused: true,
      withDebugger: true,
      structuredErrors: true,
    );
    await flutter.resume();

    final Completer<void> completer = Completer<void>();

    await Future<void>(() async {
      flutter.stdout.listen((String line) {
        stdout.writeln(line);
      });
      await completer.future;
    }).timeout(const Duration(seconds: 5), onTimeout: () {
      // We don't expect to see any output but want to write to stdout anyway.
      completer.complete();
    });
    await flutter.stop();

    expect(stdout.toString(), isNot(contains(exceptionStart)));
  });
}