Add Future.any and Stream.fromFutures.

tests/lib/async/stream_from_futures_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.
+
+import "dart:async";
+import "package:expect/expect.dart";
+import 'package:async_helper/async_helper.dart';
+
+main() {
+  asyncStart();
+
+  testValues();
+  testErrors();
+  testMixed();
+  testOrdering();
+  testEmpty();
+  testPrecompleted();
+
+  asyncEnd();
+}
+
+void testValues() {
+  asyncStart();
+  var cs = new List.generate(3, (_) => new Completer());
+  var stream = new Stream.fromFutures(cs.map((x) => x.future));
+  var result = stream.toList();
+
+  result.then((list) {
+    Expect.listEquals([1, 2, 3], list);
+    asyncEnd();
+  });
+
+  cs[1].complete(1);
+  cs[2].complete(2);
+  cs[0].complete(3);
+}
+
+void testErrors() {
+  asyncStart();
+  var cs = new List.generate(3, (_) => new Completer());
+  var stream = new Stream.fromFutures(cs.map((x) => x.future));
+
+  int counter = 0;
+  stream.listen((_) {
+    Expect.fail("unexpected value");
+  }, onError: (e) {
+    Expect.equals(++counter, e);
+  }, onDone: () {
+    Expect.equals(3, counter);
+    asyncEnd();
+  });
+
+  cs[1].completeError(1);
+  cs[2].completeError(2);
+  cs[0].completeError(3);
+}
+
+void testMixed() {
+  asyncStart();
+  var cs = new List.generate(3, (_) => new Completer());
+  var stream = new Stream.fromFutures(cs.map((x) => x.future));
+
+  int counter = 0;
+  stream.listen((v) {
+    Expect.isTrue(counter == 0 || counter == 2);
+    Expect.equals(++counter, v);
+  }, onError: (e) {
+    Expect.equals(++counter, 2);
+    Expect.equals(2, e);
+  }, onDone: () {
+    Expect.equals(3, counter);
+    asyncEnd();
+  });
+
+  cs[1].complete(1);
+  cs[2].completeError(2);
+  cs[0].complete(3);
+}
+
+void testOrdering() {
+  // The output is in completion order, not affected by the input future order.
+  test(n1, n2, n3) {
+    asyncStart();
+    var cs = new List.generate(3, (_) => new Completer());
+    var stream = new Stream.fromFutures(cs.map((x) => x.future));
+    var result = stream.toList();
+
+    result.then((list) {
+      Expect.listEquals([1, 2, 3], list);
+      asyncEnd();
+    });
+
+    cs[n1].complete(1);
+    cs[n2].complete(2);
+    cs[n3].complete(3);
+  }
+  test(0, 1, 2);
+  test(0, 2, 1);
+  test(1, 0, 2);
+  test(1, 2, 0);
+  test(2, 0, 1);
+  test(2, 1, 0);
+}
+
+void testEmpty() {
+  asyncStart();
+  var stream = new Stream.fromFutures([]);
+
+  stream.listen((_) {
+    Expect.fail("unexpected value");
+  }, onError: (e) {
+    Expect.fail("unexpected error");
+  }, onDone: () {
+    asyncEnd();
+  });
+}
+
+void testPrecompleted() {
+  asyncStart();
+  var stream = new Stream.fromFutures(
+      new Iterable.generate(3, (v) => new Future.value(v + 1)));
+  var expected = new Set.from([1, 2, 3]);
+  stream.listen((v) {
+    Expect.isTrue(expected.contains(v));
+    expected.remove(v);
+  }, onDone: () {
+    Expect.isTrue(expected.isEmpty);
+    asyncEnd();
+  });
+}