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packages/quiver/test/iterables/generating_iterable_test.dart

+// Copyright 2014 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.iterables.property_iterable_test;
+
+import 'package:test/test.dart';
+import 'package:quiver/iterables.dart';
+
+main() {
+  group('GeneratingIterable', () {
+    test("should create an empty iterable for a null start object", () {
+      var iterable = new GeneratingIterable(() => null, (n) => null);
+      expect(iterable, []);
+    });
+
+    test("should create one-item empty iterable when next returns null", () {
+      var iterable = new GeneratingIterable(() => "Hello", (n) => null);
+      expect(iterable, ["Hello"]);
+    });
+
+    test("should add items until next returns null", () {
+      var parent = new Node();
+      var node = new Node()..parent = parent;
+      var iterable = new GeneratingIterable<Node>(() => node, (n) => n.parent);
+      expect(iterable, [node, parent]);
+    });
+  });
+}
+
+class Node {
+  Node parent;
+}