Report all swarming and isolate fatal errors in a consistent way.

tests/isolate_smoke_test.py

 #!/usr/bin/env python
 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import cStringIO
 import hashlib
 import json
 import logging
 import os
@@ skipping 346 matching lines @@
     try:
       self._execute(mode, 'missing_trailing_slash.isolate', [], True)
       self.fail()
     except subprocess.CalledProcessError as e:
       self.assertEqual('', e.output)
       out = e.stderr
     self._expect_no_tree()
     self._expect_no_result()
     root = file_path.get_native_path_case(unicode(ROOT_DIR))
     expected = (
-      '\n'
-      'Error: Input directory %s must have a trailing slash\n' %
+      'Input directory %s must have a trailing slash' %
           os.path.join(root, 'tests', 'isolate', 'files1')
     )
-    self.assertEqual(expected, out)
+    self.assertIn(expected, out)
 
   def _test_non_existent(self, mode):
     try:
       self._execute(mode, 'non_existent.isolate', [], True)
       self.fail()
     except subprocess.CalledProcessError as e:
       self.assertEqual('', e.output)
       out = e.stderr
     self._expect_no_tree()
     self._expect_no_result()
     root = file_path.get_native_path_case(unicode(ROOT_DIR))
     expected = (
-      '\n'
-      'Error: Input file %s doesn\'t exist\n' %
+      'Input file %s doesn\'t exist' %
           os.path.join(root, 'tests', 'isolate', 'A_file_that_do_not_exist')
     )
-    self.assertEqual(expected, out)
+    self.assertIn(expected, out)
 
   def _test_all_items_invalid(self, mode):
     out = self._execute(mode, 'all_items_invalid.isolate',
                         ['--ignore_broken_item'], True)
     self._expect_results(['empty.py'], None, None, None)
 
     return out or ''
 
 
 class Isolate(unittest.TestCase):
@@ skipping 436 matching lines @@
 
   def test_no_run(self):
     try:
       self._execute('trace', 'no_run.isolate', [], True)
       self.fail()
     except subprocess.CalledProcessError, e:
       out = e.output
       err = e.stderr
     self._expect_no_tree()
     self._expect_no_result()
-    expected = '\nError: No command to run.\n'
+    expected = 'No command to run.'
     self.assertEqual('', out)
-    self.assertEqual(expected, err)
+    self.assertIn(expected, err)
 
   # TODO(csharp): Disabled until crbug.com/150823 is fixed.
   def do_not_test_touch_only(self):
     out = self._execute(
         'trace', 'touch_only.isolate', ['-V', 'FLAG', 'trace'], True)
     self.assertEqual('', out)
     self._expect_no_tree()
     empty = os.path.join('files1', 'test_file1.txt')
     self._expect_results(
         ['touch_only.py', 'trace'], None, {u'FLAG': u'trace'}, empty)
@@ skipping 310 matching lines @@
     self.assertEqual('Simply works.\n', stdout)
     self.assertEqual(0, proc.returncode)
 
 
 if __name__ == '__main__':
   VERBOSE = '-v' in sys.argv
   logging.basicConfig(level=logging.DEBUG if VERBOSE else logging.ERROR)
   if VERBOSE:
     unittest.TestCase.maxDiff = None
   unittest.main()