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packages/quiver/test/core/core_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.core_test;
+
+import 'package:quiver/core.dart';
+import 'package:test/test.dart';
+
+main() {
+  group('firstNonNull', () {
+    test("should return the first argument if it isn't null", () {
+      expect(firstNonNull(1, 2), 1);
+    });
+
+    test("should return the second argument if it isn't null", () {
+      expect(firstNonNull(null, 2), 2);
+    });
+
+    test("should return the third argument if it isn't null", () {
+      expect(firstNonNull(null, null, 3), 3);
+    });
+
+    test("should return the fourth argument if it isn't null", () {
+      expect(firstNonNull(null, null, null, 4), 4);
+    });
+
+    test("should throw if all argumentsare null", () {
+      expect(() => firstNonNull(null, null, null, null), throwsArgumentError);
+    });
+  });
+}