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packages/quiver/test/async/future_group_test.dart

+// Copyright 2013 Google Inc. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+library quiver.async.future_group_test;
+
+import 'dart:async';
+
+import 'package:test/test.dart';
+import 'package:quiver/async.dart';
+
+main() {
+  group('FutureGroup', () {
+    test('should complete when all added futures are complete', () {
+      var group = new FutureGroup();
+      var completer1 = new Completer();
+      var completer2 = new Completer();
+      bool completed = false;
+
+      group.add(completer1.future);
+
+      scheduleMicrotask(() {
+        expect(completed, false);
+        group.add(completer2.future);
+        completer1.complete(1);
+        scheduleMicrotask(() {
+          expect(completed, false);
+          completer2.complete(2);
+          expect(completed, false);
+        });
+      });
+
+      return group.future.then((results) {
+        completed = true;
+        expect(results, [1, 2]);
+      });
+    });
+
+    test('should throw if adding a future after the group is completed', () {
+      var group = new FutureGroup();
+      var completer1 = new Completer();
+      var completer2 = new Completer();
+
+      group.add(completer1.future);
+      completer1.complete(1);
+      return new Future(() {
+        expect(() => group.add(completer2.future), throws);
+      });
+    });
+  });
+}