pkg/matcher: reapply 36881,36896 working around Issue 19173

pkg/matcher/test/future_matchers_test.dart

Index: pkg/matcher/test/future_matchers_test.dart
diff --git a/pkg/matcher/test/future_matchers_test.dart b/pkg/matcher/test/future_matchers_test.dart
new file mode 100644
index 0000000000000000000000000000000000000000..6fac0de819f17d5d872d5aaa93097056ed3286fb
--- /dev/null
+++ b/pkg/matcher/test/future_matchers_test.dart
@@ -0,0 +1,76 @@
+// Copyright (c) 2012, 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.
+
+library matcher.future_matchers_test;
+
+import 'dart:async';
+
+import 'package:matcher/matcher.dart';
+import 'package:unittest/unittest.dart' show test, group;
+
+import 'test_utils.dart';
+
+void main() {
+  initUtils();
+
+  test('completes - unexpected error', () {
+    var completer = new Completer();
+    completer.completeError('X');
+    shouldFail(completer.future, completes,
+        contains('Expected future to complete successfully, '
+                 'but it failed with X'),
+        isAsync: true);
+  });
+
+  test('completes - successfully', () {
+    var completer = new Completer();
+    completer.complete('1');
+    shouldPass(completer.future, completes, isAsync: true);
+  });
+
+  test('throws - unexpected to see normal completion', () {
+    var completer = new Completer();
+    completer.complete('1');
+    shouldFail(completer.future, throws,
+      contains("Expected future to fail, but succeeded with '1'"),
+      isAsync: true);
+  });
+
+  test('throws - expected to see exception', () {
+    var completer = new Completer();
+    completer.completeError('X');
+    shouldPass(completer.future, throws, isAsync: true);
+  });
+
+  test('throws - expected to see exception thrown later on', () {
+    var completer = new Completer();
+    var chained = completer.future.then((_) { throw 'X'; });
+    shouldPass(chained, throws, isAsync: true);
+    completer.complete('1');
+  });
+
+  test('throwsA - unexpected normal completion', () {
+    var completer = new Completer();
+    completer.complete('1');
+    shouldFail(completer.future, throwsA(equals('X')),
+      contains("Expected future to fail, but succeeded with '1'"),
+      isAsync: true);
+  });
+
+  test('throwsA - correct error', () {
+    var completer = new Completer();
+    completer.completeError('X');
+    shouldPass(completer.future, throwsA(equals('X')), isAsync: true);
+  });
+
+  test('throwsA - wrong error', () {
+    var completer = new Completer();
+    completer.completeError('X');
+    shouldFail(completer.future, throwsA(equals('Y')),
+        "Expected: 'Y' Actual: 'X' "
+        "Which: is different. "
+        "Expected: Y Actual: X ^ Differ at offset 0",
+        isAsync: true);
+  });
+}