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packages/quiver/test/cache/map_cache_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.cache.map_cache_test;
+
+import 'dart:async';
+import 'package:test/test.dart';
+import 'package:quiver/cache.dart';
+
+main() {
+  group('MapCache', () {
+    MapCache cache;
+
+    setUp(() {
+      cache = new MapCache();
+    });
+
+    test("should return null for a non-existent key", () {
+      return cache.get('foo').then((value) {
+        expect(value, isNull);
+      });
+    });
+
+    test("should return a previously set key/value pair", () {
+      return cache
+          .set('foo', 'bar')
+          .then((_) => cache.get('foo'))
+          .then((value) {
+        expect(value, 'bar');
+      });
+    });
+
+    test("should invalidate a key", () {
+      return cache
+          .set('foo', 'bar')
+          .then((_) => cache.invalidate('foo'))
+          .then((_) => cache.get('foo'))
+          .then((value) {
+        expect(value, null);
+      });
+    });
+
+    test("should load a value given a synchronous loader", () {
+      return cache.get('foo', ifAbsent: (k) => k + k).then((value) {
+        expect(value, 'foofoo');
+      });
+    });
+
+    test("should load a value given an asynchronous loader", () {
+      return cache
+          .get('foo', ifAbsent: (k) => new Future.value(k + k))
+          .then((value) {
+        expect(value, 'foofoo');
+      });
+    });
+  });
+}