Add StreamSubscription.asFuture.

tests/lib/async/stream_subscription_as_future_test.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.
+
+// Test the Stream.single method.
+library stream_single_test;
+
+import "package:expect/expect.dart";
+import 'dart:async';
+import '../../../pkg/unittest/lib/unittest.dart';
+
+main() {
+  test("subscription.asStream success", () {
+    Stream stream = new Stream.fromIterable([1, 2, 3]);
+    var output = [];
+    var subscription = stream.listen((x) { output.add(x); });
+    subscription.asFuture(output).then(expectAsync1((o) {
+      Expect.listEquals([1, 2, 3], o);
+    }));
+  });
+
+  test("subscription.asStream success2", () {
+    StreamController controller = new StreamController();
+    [1, 2, 3].forEach(controller.add);
+    controller.close();
+    Stream stream = controller.stream;
+    var output = [];
+    var subscription = stream.listen((x) { output.add(x); });
+    subscription.asFuture(output).then(expectAsync1((o) {
+      Expect.listEquals([1, 2, 3], o);
+    }));
+  });
+
+  test("subscription.asStream success 3", () {
+    Stream stream = new Stream.fromIterable([1, 2, 3]).map((x) => x);
+    var output = [];
+    var subscription = stream.listen((x) { output.add(x); });
+    subscription.asFuture(output).then(expectAsync1((o) {
+      Expect.listEquals([1, 2, 3], o);
+    }));
+  });
+
+  test("subscription.asStream failure", () {
+    StreamController controller = new StreamController();
+    [1, 2, 3].forEach(controller.add);
+    controller.addError("foo");
+    controller.close();
+    Stream stream = controller.stream;
+    var output = [];
+    var subscription = stream.listen((x) { output.add(x); });
+    subscription.asFuture(output).catchError(expectAsync1((e) {
+      Expect.equals(e.error, "foo");
+    }));
+  });
+
+  test("subscription.asStream failure2", () {
+    Stream stream = new Stream.fromIterable([1, 2, 3, 4])
+      .map((x) {
+        if (x == 4) throw "foo";
+        return x;
+      });
+    var output = [];
+    var subscription = stream.listen((x) { output.add(x); });
+    subscription.asFuture(output).catchError(expectAsync1((e) {
+      Expect.equals(e.error, "foo");
+    }));
+  });
+}