Add pretty-printing to unittest and more thoroughly print values.

pkg/unittest/test/unittest_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.
 
 // TODO(gram):
 // Unfortunately I can't seem to test anything that involves timeouts, e.g.
 // insufficient callbacks, because the timeout is controlled externally
 // (test.dart?), and we would need to use a shorter timeout for the inner tests
 // so the outer timeout doesn't fire. So I removed all such tests.
 // I'd like to revisit this at some point.
@@ skipping 387 matching lines @@
         expect(s.toString(), "EGHIHJHKHL");
       });
     }
   });
 }
 
 main() {
   var tests = {
     'single correct test': buildStatusString(1, 0, 0, 'single correct test'),
     'single failing test': buildStatusString(0, 1, 0, 'single failing test',
-        message: 'Expected: <5> but: was <4>.'),
+        message: 'Expected: <5> But: was <4>.'),
     'exception test': buildStatusString(0, 1, 0, 'exception test',
         message: 'Caught Exception: Fail.'),
     'group name test': buildStatusString(2, 0, 0, 'a a::a b b'),
     'setup test': buildStatusString(1, 0, 0, 'a setup test',
         count: 0, setup: 'setup'),
     'teardown test': buildStatusString(1, 0, 0, 'a teardown test',
         count: 0, setup: '', teardown: 'teardown'),
     'setup and teardown test': buildStatusString(1, 0, 0,
         'a setup and teardown test', count: 0, setup: 'setup',
         teardown: 'teardown'),
     'correct callback test': buildStatusString(1, 0, 0, 'correct callback test',
         count: 1),
     'excess callback test': buildStatusString(0, 1, 0, 'excess callback test',
         count: 1, message: 'Callback called more times than expected (1).'),
     'completion test': buildStatusString(1, 0, 0, 'completion test', count: 10),
     'async exception test': buildStatusString(0, 1, 0, 'async exception test',
         message: 'Caught error!'),
     'late exception test': buildStatusString(1, 0, 1, 'testOne',
         message: 'Callback called (2) after test case testOne has already '
                  'been marked as pass.:testTwo:'),
     'middle exception test': buildStatusString(2, 1, 0,
-        'testOne::testTwo:Expected: false but: was <true>.:testThree'),
+        'testOne::testTwo:Expected: false But: was <true>.:testThree'),
     'async setup/teardown test': buildStatusString(2, 0, 3,
         'good setup/good teardown foo1::'
         'good setup/bad teardown foo2:good setup/bad teardown '
         'foo2: Test teardown failed: Failed to complete tearDown:'
         'bad setup/good teardown foo3:bad setup/good teardown '
         'foo3: Test setup failed: Failed to complete setUp:'
         'bad setup/bad teardown foo4:bad setup/bad teardown '
         'foo4: Test teardown failed: Failed to complete tearDown:'
         'post groups'),
     'test returning future': buildStatusString(2, 4, 0,
         'successful::'
         'error1:Callback called more times than expected (1).:'
-        'fail1:Expected: <false> but: was <true>.:'
+        'fail1:Expected: <false> But: was <true>.:'
         'error2:Callback called more times than expected (1).:'
         'fail2:failure:'
         'foo5'),
     'test returning future using runAsync': buildStatusString(2, 4, 0,
         'successful::'
-        'fail1:Expected: <false> but: was <true>.:'
+        'fail1:Expected: <false> But: was <true>.:'
         'error1:Callback called more times than expected (1).:'
         'fail2:failure:'
         'error2:Callback called more times than expected (1).:'
         'foo6'),
     'testCases immutable':
         buildStatusString(1, 0, 0, 'testCases immutable'),
     'runTests without tests': buildStatusString(0, 0, 0, null),
     'nested groups setup/teardown':
         buildStatusString(2, 0, 0,
             'level 1 level 2 level 3 level 4 level 5 level 6 inner::'
@@ skipping 10 matching lines @@
             'final')
   };
 
   tests.forEach((String name, String expected) {
     test(name, () => spawnFunction(runTest)
         .call(name)
         .then((String msg) => expect(msg.trim(), equals(expected))));
     });
 }