Make Stream.where, etc., be documented as inheriting broadcast state.

tests/lib/async/stream_transformation_broadcast_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 that transformations like `map` and `where` preserve broadcast flag.
+library stream_join_test;
+
+import 'dart:async';
+import 'event_helper.dart';
+import 'package:unittest/unittest.dart';
+import "package:expect/expect.dart";
+
+void testStream(String name,
+                StreamController create(),
+                Stream getStream(controller)) {
+  test("$name-map", () {
+    var c = create();
+    var s = getStream(c);
+    Stream newStream = s.map((x) => x + 1);
+    Expect.equals(s.isBroadcast, newStream.isBroadcast);
+    newStream.single.then(expectAsync((v) {
+      Expect.equals(43, v);
+    }));
+    c.add(42);
+    c.close();
+  });
+  test("$name-where", () {
+    var c = create();
+    var s = getStream(c);
+    Stream newStream = s.where((x) => x.isEven);
+    Expect.equals(s.isBroadcast, newStream.isBroadcast);
+    newStream.single.then(expectAsync((v) {
+      Expect.equals(42, v);
+    }));
+    c.add(37);
+    c.add(42);
+    c.add(87);
+    c.close();
+  });
+  test("$name-handleError", () {
+    var c = create();
+    var s = getStream(c);
+    Stream newStream = s.handleError((x, s) {});
+    Expect.equals(s.isBroadcast, newStream.isBroadcast);
+    newStream.single.then(expectAsync((v) {
+      Expect.equals(42, v);
+    }));
+    c.addError("BAD1");
+    c.add(42);
+    c.addError("BAD2");
+    c.close();
+  });
+  test("$name-expand", () {
+    var c = create();
+    var s = getStream(c);
+    Stream newStream = s.expand((x) => x.isEven ? [x] : []);
+    Expect.equals(s.isBroadcast, newStream.isBroadcast);
+    newStream.single.then(expectAsync((v) {
+      Expect.equals(42, v);
+    }));
+    c.add(37);
+    c.add(42);
+    c.add(87);
+    c.close();
+  });
+  test("$name-transform", () {
+    var c = create();
+    var s = getStream(c);
+    // TODO: find name of default transformer
+    var t = new StreamTransformer.fromHandlers(
+        handleData: (value, EventSink sink) { sink.add(value); }
+    );
+    Stream newStream = s.transform(t);
+    Expect.equals(s.isBroadcast, newStream.isBroadcast);
+    newStream.single.then(expectAsync((v) {
+      Expect.equals(42, v);
+    }));
+    c.add(42);
+    c.close();
+  });
+  test("$name-take", () {
+    var c = create();
+    var s = getStream(c);
+    Stream newStream = s.take(1);
+    Expect.equals(s.isBroadcast, newStream.isBroadcast);
+    newStream.single.then(expectAsync((v) {
+      Expect.equals(42, v);
+    }));
+    c.add(42);
+    c.add(37);
+    c.close();
+  });
+  test("$name-takeWhile", () {
+    var c = create();
+    var s = getStream(c);
+    Stream newStream = s.takeWhile((x) => x.isEven);
+    Expect.equals(s.isBroadcast, newStream.isBroadcast);
+    newStream.single.then(expectAsync((v) {
+      Expect.equals(42, v);
+    }));
+    c.add(42);
+    c.add(37);
+    c.close();
+  });
+  test("$name-skip", () {
+    var c = create();
+    var s = getStream(c);
+    Stream newStream = s.skip(1);
+    Expect.equals(s.isBroadcast, newStream.isBroadcast);
+    newStream.single.then(expectAsync((v) {
+      Expect.equals(42, v);
+    }));
+    c.add(37);
+    c.add(42);
+    c.close();
+  });
+  test("$name-skipWhile", () {
+    var c = create();
+    var s = getStream(c);
+    Stream newStream = s.skipWhile((x) => x.isOdd);
+    Expect.equals(s.isBroadcast, newStream.isBroadcast);
+    newStream.single.then(expectAsync((v) {
+      Expect.equals(42, v);
+    }));
+    c.add(37);
+    c.add(42);
+    c.close();
+  });
+  test("$name-distinct", () {
+    var c = create();
+    var s = getStream(c);
+    Stream newStream = s.distinct();
+    Expect.equals(s.isBroadcast, newStream.isBroadcast);
+    newStream.single.then(expectAsync((v) {
+      Expect.equals(42, v);
+    }));
+    c.add(42);
+    c.add(42);
+    c.close();
+  });
+  test("$name-timeout", () {
+    var c = create();
+    var s = getStream(c);
+    Stream newStream = s.timeout(const Duration(seconds: 1));
+    Expect.equals(s.isBroadcast, newStream.isBroadcast);
+    newStream.single.then(expectAsync((v) {
+      Expect.equals(42, v);
+    }));
+    c.add(42);
+    c.close();
+  });
+  test("$name-asyncMap", () {
+    var c = create();
+    var s = getStream(c);
+    Stream newStream = s.asyncMap((x) => new Future.value(x + 1));
+    Expect.equals(s.isBroadcast, newStream.isBroadcast);
+    newStream.single.then(expectAsync((v) {
+      Expect.equals(43, v);
+    }));
+    c.add(42);
+    c.close();
+  });
+  test("$name-asyncExpand", () {
+    var c = create();
+    var s = getStream(c);
+    Stream newStream = s.asyncExpand((x) => new Stream.fromIterable([x + 1]));
+    Expect.equals(s.isBroadcast, newStream.isBroadcast);
+    newStream.single.then(expectAsync((v) {
+      Expect.equals(43, v);
+    }));
+    c.add(42);
+    c.close();
+  });
+}
+
+main() {
+  testStream("singlesub", () => new StreamController(), (c) => c.stream);
+  testStream("broadcast", () => new StreamController.broadcast(),
+                          (c) => c.stream);
+  testStream("asBroadcast", () => new StreamController(),
+                            (c) => c.stream.asBroadcastStream());
+  testStream("broadcast.asBroadcast", () => new StreamController.broadcast(),
+                                      (c) => c.stream.asBroadcastStream());
+}