| // Copyright (c) 2015, 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 'package:async/async.dart'; |
| import 'package:test/test.dart'; |
| |
| main() { |
| AsyncMemoizer cache; |
| setUp(() => cache = new AsyncMemoizer()); |
| |
| test("runs the function only the first time runOnce() is called", () async { |
| var count = 0; |
| expect(await cache.runOnce(() => count++), equals(0)); |
| expect(count, equals(1)); |
| |
| expect(await cache.runOnce(() => count++), equals(0)); |
| expect(count, equals(1)); |
| }); |
| |
| test("forwards the return value from the function", () async { |
| expect(cache.future, completion(equals("value"))); |
| expect(cache.runOnce(() => "value"), completion(equals("value"))); |
| expect(cache.runOnce(() {}), completion(equals("value"))); |
| }); |
| |
| test("forwards the return value from an async function", () async { |
| expect(cache.future, completion(equals("value"))); |
| expect(cache.runOnce(() async => "value"), completion(equals("value"))); |
| expect(cache.runOnce(() {}), completion(equals("value"))); |
| }); |
| |
| test("forwards the error from an async function", () async { |
| expect(cache.future, throwsA("error")); |
| expect(cache.runOnce(() async => throw "error"), throwsA("error")); |
| expect(cache.runOnce(() {}), throwsA("error")); |
| }); |
| } |