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packages/unittest/test/test_utils.dart

+// 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 unittest.matcher.test_utils;
+
+import 'dart:async';
+
+import 'package:unittest/unittest.dart';
+
+int _errorCount;
+String _errorString;
+FailureHandler _testHandler = null;
+
+class MyFailureHandler extends DefaultFailureHandler {
+  void fail(String reason) {
+    ++_errorCount;
+    _errorString = reason;
+  }
+}
+
+void initUtils() {
+  if (_testHandler == null) {
+    _testHandler = new MyFailureHandler();
+  }
+}
+
+void shouldFail(value, Matcher matcher, expected, {bool isAsync: false}) {
+  configureExpectFailureHandler(_testHandler);
+  _errorCount = 0;
+  _errorString = '';
+  expect(value, matcher);
+  afterTest() {
+    configureExpectFailureHandler(null);
+    expect(_errorCount, equals(1));
+    if (expected is String) {
+      expect(_errorString, equalsIgnoringWhitespace(expected));
+    } else {
+      expect(_errorString.replaceAll('\n', ''), expected);
+    }
+  }
+
+  if (isAsync) {
+    Timer.run(expectAsync(afterTest));
+  } else {
+    afterTest();
+  }
+}
+
+void shouldPass(value, Matcher matcher, {bool isAsync: false}) {
+  configureExpectFailureHandler(_testHandler);
+  _errorCount = 0;
+  _errorString = '';
+  expect(value, matcher);
+  afterTest() {
+    configureExpectFailureHandler(null);
+    expect(_errorCount, equals(0));
+  }
+  if (isAsync) {
+    Timer.run(expectAsync(afterTest));
+  } else {
+    afterTest();
+  }
+}
+
+doesNotThrow() {}
+doesThrow() {
+  throw 'X';
+}
+
+class PrefixMatcher extends Matcher {
+  final String _prefix;
+  const PrefixMatcher(this._prefix);
+  bool matches(item, Map matchState) {
+    return item is String &&
+        (collapseWhitespace(item)).startsWith(collapseWhitespace(_prefix));
+  }
+
+  Description describe(Description description) => description
+      .add('a string starting with ')
+      .addDescriptionOf(collapseWhitespace(_prefix))
+      .add(' ignoring whitespace');
+}