pkg/testing/lib/src/discover.dart

// Copyright (c) 2016, 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.

library;

import 'dart:io' show Directory, FileSystemEntity, Platform, Process;

import 'dart:async' show Future, Stream, StreamController, StreamSubscription;

import '../testing.dart' show FileBasedTestDescription;

final Uri packageConfig = computePackageConfig();

/// Common arguments when running a dart program. Returns a copy that can
/// safely be modified by caller.
List<String> get dartArguments => <String>[
  "-c",
  "--packages=${packageConfig.toFilePath()}",
];

Stream<FileBasedTestDescription> listTests(
  List<Uri> testRoots, {
  Pattern? pattern,
}) {
  StreamController<FileBasedTestDescription> controller =
      StreamController<FileBasedTestDescription>();
  Map<Uri, StreamSubscription?> subscriptions = <Uri, StreamSubscription>{};
  for (Uri testRootUri in testRoots) {
    subscriptions[testRootUri] = null;
    Directory testRoot = Directory.fromUri(testRootUri);
    testRoot.exists().then((bool exists) {
      if (exists) {
        Stream<FileSystemEntity> stream = testRoot.list(
          recursive: true,
          followLinks: false,
        );
        var subscription = stream.listen(
          (FileSystemEntity entity) {
            FileBasedTestDescription? description =
                FileBasedTestDescription.from(
                  testRootUri,
                  entity,
                  pattern: pattern,
                );
            if (description != null) {
              controller.add(description);
            }
          },
          onError: (error, StackTrace trace) {
            controller.addError(error, trace);
          },
          onDone: () {
            subscriptions.remove(testRootUri);
            if (subscriptions.isEmpty) {
              controller.close(); // TODO(ahe): catchError???
            }
          },
        );
        subscriptions[testRootUri] = subscription;
      } else {
        controller.addError("$testRootUri isn't a directory");
        subscriptions.remove(testRootUri);
      }
      if (subscriptions.isEmpty) {
        controller.close(); // TODO(ahe): catchError???
      }
    });
  }
  return controller.stream;
}

Uri computePackageConfig() {
  String? path = Platform.packageConfig;
  if (path != null) return Uri.base.resolve(path);
  return Uri.base.resolve(".dart_tool/package_config.json");
}

Future<Process> startDart(
  Uri program, [
  List<String>? arguments,
  List<String>? vmArguments,
]) {
  List<String> allArguments = <String>[];
  allArguments.addAll(vmArguments ?? dartArguments);
  allArguments.add(program.toFilePath());
  if (arguments != null) {
    allArguments.addAll(arguments);
  }
  return Process.start(Platform.resolvedExecutable, allArguments);
}