Add a LiveSuite class.

lib/src/runner/live_suite_controller.dart

Index: lib/src/runner/live_suite_controller.dart
diff --git a/lib/src/runner/live_suite_controller.dart b/lib/src/runner/live_suite_controller.dart
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index 0000000000000000000000000000000000000000..4cacf2b94518f28f4867ee33534c146cf948fb80
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+++ b/lib/src/runner/live_suite_controller.dart
@@ -0,0 +1,155 @@
+// 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.
+
+import 'dart:async';
+
+import 'package:async/async.dart' hide Result;
+import 'package:collection/collection.dart';
+
+import '../backend/state.dart';
+import '../backend/live_test.dart';
+import 'live_suite.dart';
+import 'runner_suite.dart';
+
+/// An implementation of [LiveSuite] that's controlled by a
+/// [LiveSuiteController].
+class _LiveSuite extends LiveSuite {
+  final LiveSuiteController _controller;
+
+  RunnerSuite get suite => _controller._suite;
+
+  bool get isComplete => _controller._isComplete;
+
+  Future get onComplete => _controller._onCompleteGroup.future;
+
+  bool get isClosed => _controller._onCloseCompleter.isCompleted;
+
+  Future get onClose => _controller._onCloseCompleter.future;
+
+  Stream<LiveTest> get onTestStarted =>
+      _controller._onTestStartedController.stream;
+
+  Set<LiveTest> get passed => new UnmodifiableSetView(_controller._passed);
+
+  Set<LiveTest> get skipped => new UnmodifiableSetView(_controller._skipped);
+
+  Set<LiveTest> get failed => new UnmodifiableSetView(_controller._failed);
+
+  LiveTest get active => _controller._active;
+
+  _LiveSuite(this._controller);
+}
+
+/// A controller that drives a [LiveSuite].
+///
+/// This is a utility class to make it easier for [Engine] to create the
+/// [LiveSuite]s exposed by various APIs. The [LiveSuite] is accessible through
+/// [LiveSuiteController.liveSuite]. When a live test is run, it should be
+/// passed to [reportLiveTest], and once tests are finished being run for this
+/// suite, [noMoreLiveTests] should be called. Once the suite should be torn
+/// down, [close] should be called.
+class LiveSuiteController {
+  /// The [LiveSuite] controlled by [this].
+  LiveSuite get liveSuite => _liveSuite;
+  LiveSuite _liveSuite;
+
+  /// The suite that's being run.
+  final RunnerSuite _suite;
+
+  /// The future group that backs [LiveSuite.onComplete].
+  ///
+  /// This contains all the futures from tests that are run in this suite.
+  final _onCompleteGroup = new FutureGroup();
+
+  /// Whether [_onCompleteGroup]'s future has fired.
+  var _isComplete = false;
+
+  /// The completer that backs [LiveSuite.onClose].
+  ///
+  /// This is completed when the live suite is closed.
+  final _onCloseCompleter = new Completer();
+
+  /// The controller for [LiveSuite.onTestStarted].
+  final _onTestStartedController =
+      new StreamController<LiveTest>.broadcast(sync: true);
+
+  /// The set that backs [LiveTest.passed].
+  final _passed = new Set<LiveTest>();
+
+  /// The set that backs [LiveTest.skipped].
+  final _skipped = new Set<LiveTest>();
+
+  /// The set that backs [LiveTest.failed].
+  final _failed = new Set<LiveTest>();
+
+  /// The test exposed through [LiveTest.active].
+  LiveTest _active;
+
+  /// Creates a controller for a live suite representing running the tests in
+  /// [suite].
+  ///
+  /// Once this is called, the controller assumes responsibility for closing the
+  /// suite. The caller should call [LiveSuiteController.close] rather than
+  /// calling [RunnerSuite.close] directly.
+  LiveSuiteController(this._suite) {
+    _liveSuite = new _LiveSuite(this);
+
+    _onCompleteGroup.future.then((_) {
+      _isComplete = true;
+    }, onError: (_) {});
+  }
+
+  /// Reports the status of [liveTest] through [liveSuite].
+  ///
+  /// The live test is assumed to be a member of this suite. If [countSuccess]
+  /// is `true` (the default), the test is put into [passed] if it succeeds.
+  /// Otherwise, it's removed from [liveTests] entirely.
+  ///
+  /// Throws a [StateError] if called after [noMoreLiveTests].
+  void reportLiveTest(LiveTest liveTest, {bool countSuccess: true}) {
+    if (_onTestStartedController.isClosed) {
+      throw new StateError("Can't call reportLiveTest() after noMoreTests().");
+    }
+
+    assert(liveTest.suite == _suite);
+    assert(_active == null);
+
+    _active = liveTest;
+
+    liveTest.onStateChange.listen((state) {
+      if (state.status != Status.complete) return;
+      _active = null;
+
+      if (state.result != Result.success) {
+        _passed.remove(liveTest);
+        _failed.add(liveTest);
+      } else if (liveTest.test.metadata.skip) {
+        _skipped.add(liveTest);
+      } else if (countSuccess) {
+        _passed.add(liveTest);
+      }
+    });
+
+    _onTestStartedController.add(liveTest);
+
+    _onCompleteGroup.add(liveTest.onComplete);
+  }
+
+  /// Indicates that all the live tests that are going to be provided for this
+  /// suite have already been provided.
+  void noMoreLiveTests() {
+    _onTestStartedController.close();
+    _onCompleteGroup.close();
+  }
+
+  /// Closes the underlying suite.
+  Future close() => _closeMemo.runOnce(() async {
+    try {
+      await _suite.close();
+    } finally {
+      _onCloseCompleter.complete();
+    }
+  });
+  final _closeMemo = new AsyncMemoizer();
+}