Improved error messages from unittest.

pkg/unittest/test/matchers_minified_test.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.
 
 // This file is for matcher tests that rely on the names of various Dart types.
 // These tests normally fail when run in minified dart2js, since the names will
 // be mangled. This version of the file is modified to expect minified names.
 
 import 'package:unittest/unittest.dart';
 
 import 'test_common.dart';
 import 'test_utils.dart';
 
 // A regexp fragment matching a minified name.
 final _minifiedName = r"[A-Za-z0-9]{1,3}";
 
 void main() {
   initUtils();
 
   group('Core matchers', () {
     test('throwsFormatException', () {
       shouldPass(() { throw new FormatException(''); },
           throwsFormatException);
       shouldFail(() { throw new Exception(); },
           throwsFormatException,
           matches(
-              r"Expected: throws an exception which matches FormatException +"
-              r"But:  exception " + _minifiedName + r":<Exception> "
-                  r"does not match FormatException\."
-              r"Actual: <Closure>"));
+              r"Expected: throws FormatException +"
+              r"Actual: <Closure(: \(dynamic\) => dynamic)?> +"
+              r"Which: threw " + _minifiedName + r":<Exception>"));
     });
 
     test('throwsArgumentError', () {
       shouldPass(() { throw new ArgumentError(''); },
           throwsArgumentError);
       shouldFail(() { throw new Exception(); },
           throwsArgumentError,
           matches(
-              r"Expected: throws an exception which matches ArgumentError +"
-              r"But:  exception " + _minifiedName + r":<Exception> "
-                  r"does not match ArgumentError\."
-              r"Actual: <Closure>"));
+              r"Expected: throws ArgumentError +"
+              r"Actual: <Closure(: \(dynamic\) => dynamic)?> +"
+              r"Which: threw " + _minifiedName + r":<Exception>"));
     });
 
     test('throwsRangeError', () {
       shouldPass(() { throw new RangeError(0); },
           throwsRangeError);
       shouldFail(() { throw new Exception(); },
           throwsRangeError,
           matches(
-              r"Expected: throws an exception which matches RangeError +"
-              r"But:  exception " + _minifiedName + r":<Exception> "
-                  r"does not match RangeError\."
-              r"Actual: <Closure(: \(dynamic\) => dynamic)?>"));
+              r"Expected: throws RangeError +"
+              r"Actual: <Closure(: \(dynamic\) => dynamic)?> +"
+              r"Which: threw " + _minifiedName + r":<Exception>"));
     });
 
     test('throwsNoSuchMethodError', () {
       shouldPass(() { throw new NoSuchMethodError(null, '', null, null); },
           throwsNoSuchMethodError);
       shouldFail(() { throw new Exception(); },
           throwsNoSuchMethodError,
           matches(
-              r"Expected: throws an exception which matches NoSuchMethodError +"
-              r"But:  exception " + _minifiedName + r":<Exception> "
-                  r"does not match NoSuchMethodError\."
-              r"Actual: <Closure(: \(dynamic\) => dynamic)?>"));
+              r"Expected: throws NoSuchMethodError +"
+              r"Actual: <Closure(: \(dynamic\) => dynamic)?> +"
+              r"Which: threw " + _minifiedName + r":<Exception>"));
     });
 
     test('throwsUnimplementedError', () {
       shouldPass(() { throw new UnimplementedError(''); },
           throwsUnimplementedError);
       shouldFail(() { throw new Exception(); },
           throwsUnimplementedError,
           matches(
-              r"Expected: throws an exception which matches "
-                  r"UnimplementedError +"
-              r"But:  exception " + _minifiedName + r":<Exception> "
-                  r"does not match UnimplementedError\."
-              r"Actual: <Closure(: \(dynamic\) => dynamic)?>"));
+              r"Expected: throws UnimplementedError +"
+              r"Actual: <Closure(: \(dynamic\) => dynamic)?> +"
+              r"Which: threw " + _minifiedName + r":<Exception>"));
     });
 
     test('throwsUnsupportedError', () {
       shouldPass(() { throw new UnsupportedError(''); },
           throwsUnsupportedError);
       shouldFail(() { throw new Exception(); },
           throwsUnsupportedError,
           matches(
-              r"Expected: throws an exception which matches UnsupportedError +"
-              r"But:  exception " + _minifiedName + r":<Exception> "
-                  r"does not match UnsupportedError\."
-              r"Actual: <Closure(: \(dynamic\) => dynamic)?>"));
+              r"Expected: throws UnsupportedError +"
+              r"Actual: <Closure(: \(dynamic\) => dynamic)?> +"
+              r"Which: threw " + _minifiedName + r":<Exception>"));
     });
 
     test('throwsStateError', () {
       shouldPass(() { throw new StateError(''); },
           throwsStateError);
       shouldFail(() { throw new Exception(); },
           throwsStateError,
           matches(
-              r"Expected: throws an exception which matches StateError +"
-              r"But:  exception " + _minifiedName + r":<Exception> "
-                  r"does not match StateError\."
-              r"Actual: <Closure(: \(dynamic\) => dynamic)?>"));
+              r"Expected: throws StateError +"
+              r"Actual: <Closure(: \(dynamic\) => dynamic)?> +"
+              r"Which: threw " + _minifiedName + r":<Exception>"));
     });
   });
 
   group('Iterable Matchers', () {
     test('isEmpty', () {
       var d = new SimpleIterable(0);
       var e = new SimpleIterable(1);
       shouldPass(d, isEmpty);
       shouldFail(e, isEmpty,
-          matches(r"Expected: empty +But: was " + _minifiedName + r":\[1\]\."));
+          matches(r"Expected: empty +Actual: " + _minifiedName + r":\[1\]"));
     });
 
     test('contains', () {
       var d = new SimpleIterable(3);
       shouldPass(d, contains(2));
       shouldFail(d, contains(5),
           matches(
               r"Expected: contains <5> +"
-              r"But: was " + _minifiedName + r":\[3, 2, 1\]\."));
+              r"Actual: " + _minifiedName + r":\[3, 2, 1\]"));
     });
   });
 
   group('Feature Matchers', () {
     test("Feature Matcher", () {
       var w = new Widget();
       w.price = 10;
       shouldPass(w, new HasPrice(10));
       shouldPass(w, new HasPrice(greaterThan(0)));
       shouldFail(w, new HasPrice(greaterThan(10)),
           matches(
               r"Expected: Widget with a price that is a value greater than "
                   r"<10> +"
-              r"But: price was <10>\."
-              r"Actual: <Instance of '" + _minifiedName + r"'>"));
+              r"Actual: <Instance of '" + _minifiedName + r"'> +"
+              r"Which: has price with value <10> which is not "
+              r"a value greater than <10>"));
     });
   });
 }