Delete a bunch of packages that are now on GitHub.

pkg/scheduled_test/lib/src/task.dart

-// Copyright (c) 2013, 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 task;
-
-import 'dart:async';
-import 'dart:collection';
-
-import 'package:stack_trace/stack_trace.dart';
-
-import 'future_group.dart';
-import 'schedule.dart';
-import 'utils.dart';
-
-typedef Future TaskBody();
-
-/// A single task to be run as part of a [TaskQueue].
-///
-/// There are two levels of tasks. **Top-level tasks** are created by calling
-/// [TaskQueue.schedule] before the queue in question is running. They're run in
-/// sequence as part of that [TaskQueue]. **Nested tasks** are created by
-/// calling [TaskQueue.schedule] once the queue is already running, and are run
-/// in parallel as part of a top-level task.
-class Task {
-  /// The queue to which this [Task] belongs.
-  final TaskQueue queue;
-
-  /// Child tasks that have been spawned while running this task. This will be
-  /// empty if this task is a nested task.
-  List<Task> get children => new UnmodifiableListView(_children);
-  final _children = new Queue<Task>();
-
-  /// A [FutureGroup] that will complete once all current child tasks are
-  /// finished running. This will be null if no child tasks are currently
-  /// running.
-  FutureGroup _childGroup;
-
-  /// A description of this task. Used for debugging. May be `null`.
-  final String description;
-
-  /// The parent task, if this is a nested task that was started while another
-  /// task was running. This will be `null` for top-level tasks.
-  final Task parent;
-
-  /// The body of the task.
-  TaskBody fn;
-
-  /// The current state of [this].
-  TaskState get state => _state;
-  var _state = TaskState.WAITING;
-
-  /// The identifier of the task. For top-level tasks, this is the index of the
-  /// task within [queue]; for nested tasks, this is the index within
-  /// [parent.children]. It's used for debugging when [description] isn't
-  /// provided.
-  int _id;
-
-  /// A Future that will complete to the return value of [fn] once this task
-  /// finishes running.
-  Future get result => _resultCompleter.future;
-  final _resultCompleter = new Completer();
-
-  final Chain stackChain;
-
-  Task(fn(), String description, TaskQueue queue)
-      : this._(fn, description, queue, null, queue.contents.length);
-
-  Task._child(fn(), String description, Task parent)
-      : this._(fn, description, parent.queue, parent, parent.children.length);
-
-  Task._(fn(), this.description, TaskQueue queue, this.parent, this._id)
-      : queue = queue,
-        stackChain = new Chain.current() {
-    this.fn = () {
-      if (state != TaskState.WAITING) {
-        throw new StateError("Can't run $state task '$this'.");
-      }
-
-      _state = TaskState.RUNNING;
-      var future = new Future.value().then((_) => fn())
-          .whenComplete(() {
-        if (_childGroup == null || _childGroup.completed) return null;
-        return _childGroup.future;
-      });
-      chainToCompleter(future, _resultCompleter);
-      return future;
-    };
-
-    // If the parent queue experiences an error before this task has started
-    // running, pipe that error out through [result]. This ensures that we don't
-    // get deadlocked by something like `expect(schedule(...), completes)`.
-    queue.onTasksComplete.catchError((e) {
-      if (state == TaskState.WAITING) _resultCompleter.completeError(e);
-    });
-
-    // catchError makes sure any error thrown by fn isn't top-leveled by virtue
-    // of being passed to the result future.
-    result.then((_) {
-      _state = TaskState.SUCCESS;
-    }).catchError((e) {
-      _state = TaskState.ERROR;
-      throw e;
-    }).catchError((_) {});
-  }
-
-  /// Run [fn] as a child of this task. Returns a Future that will complete with
-  /// the result of the child task. This task will not complete until [fn] has
-  /// finished.
-  Future runChild(fn(), String description) {
-    var task = new Task._child(fn, description, this);
-    _children.add(task);
-    if (_childGroup == null || _childGroup.completed) {
-      _childGroup = new FutureGroup();
-    }
-    // Ignore errors in the FutureGroup; they'll get picked up via wrapFuture,
-    // and we don't want them to short-circuit the other Futures.
-    _childGroup.add(task.result.catchError((_) {}));
-    task.fn();
-    return task.result;
-  }
-
-  String toString() => description == null ? "#$_id" : description;
-
-  String toStringWithStackTrace() {
-    var stackString = prefixLines(terseTraceString(stackChain));
-    return "$this\n\nStack chain:\n$stackString";
-  }
-
-  /// Returns a detailed representation of [queue] with this task highlighted.
-  String generateTree() => queue.generateTree(this);
-}
-
-/// An enum of states for a [Task].
-class TaskState {
-  /// The task is waiting to be run.
-  static const WAITING = const TaskState._("WAITING");
-
-  /// The task is currently running.
-  static const RUNNING = const TaskState._("RUNNING");
-
-  /// The task has finished running successfully.
-  static const SUCCESS = const TaskState._("SUCCESS");
-
-  /// The task has finished running with an error.
-  static const ERROR = const TaskState._("ERROR");
-
-  /// The name of the state.
-  final String name;
-
-  /// Whether the state indicates that the task has finished running. This is
-  /// true for both the [SUCCESS] and [ERROR] states.
-  bool get isDone => this == SUCCESS || this == ERROR;
-
-  const TaskState._(this.name);
-
-  String toString() => name;
-}