rebaseline.py: add bug-filing URL to error message

tools/rebaseline.py

 #!/usr/bin/python
 
 '''
 Copyright 2012 Google Inc.
 
 Use of this source code is governed by a BSD-style license that can be
 found in the LICENSE file.
 '''
 
 '''
@@ skipping 103 matching lines @@
     going, or exit the program right away."""
     # Get traceback information about the most recently raised exception.
     exc_info = sys.exc_info()
 
     if self._keep_going_on_failure:
       print >> sys.stderr, ('WARNING: swallowing exception %s' %
                             repr(exc_info[1]))
       self._failures_encountered.append(exc_info)
     else:
       print >> sys.stderr, (
-          'Halting at first exception; to keep going, re-run ' +
-          'with the --keep-going-on-failure option set.')
+          '\nHalting at first exception.\n' +

[epoger, 2013/09/04 20:05:56]

Here's the before-and-after error message.  Any further adjustments to suggest?

BEFORE:

$ tools/rebaseline.py --actuals-base-url BADURL
Halting at first exception; to keep going, re-run with the
--keep-going-on-failure option set.
Traceback (most recent call last):
  File "tools/rebaseline.py", line 418, in <module>
    exception_handler.RaiseExceptionOrContinue()
  File "tools/rebaseline.py", line 416, in <module>
    rebaseliner.RebaselineSubdir(builder=builder)
  File "tools/rebaseline.py", line 264, in RebaselineSubdir
    sections=sections)
  File "tools/rebaseline.py", line 228, in _GetActualResults
    json_contents = self._GetFileContents(json_url)
  File "tools/rebaseline.py", line 204, in _GetFileContents
    return open(filepath, 'r').read()
IOError: [Errno 2] No such file or directory:
'BADURL/Test-Android-GalaxyNexus-SGX540-Arm7-Debug/actual-results.json'


AFTER:

$ tools/rebaseline.py --actuals-base-url BADURL

Halting at first exception.
Please file a bug, containing the following stack trace, at
https://code.google.com/p/skia/issues/entry .

Afterwards, you can re-run with the --keep-going-on-failure option set.

Traceback (most recent call last):
  File "tools/rebaseline.py", line 421, in <module>
    exception_handler.RaiseExceptionOrContinue()
  File "tools/rebaseline.py", line 419, in <module>
    rebaseliner.RebaselineSubdir(builder=builder)
  File "tools/rebaseline.py", line 267, in RebaselineSubdir
    sections=sections)
  File "tools/rebaseline.py", line 231, in _GetActualResults
    json_contents = self._GetFileContents(json_url)
  File "tools/rebaseline.py", line 207, in _GetFileContents
    return open(filepath, 'r').read()
IOError: [Errno 2] No such file or directory:
'BADURL/Test-Android-GalaxyNexus-SGX540-Arm7-Debug/actual-results.json'

[epoger, 2013/09/04 20:08:48]

Updated the message in patchset 2.

+          'Please file a bug, containing the following stack trace, ' +
+          'at https://code.google.com/p/skia/issues/entry .\n\n' +
+          'Afterwards, you can re-run with the --keep-going-on-failure ' +
+          'option set.\n')
       raise exc_info[1], None, exc_info[2]
 
   def ReportAllFailures(self):
     if self._failures_encountered:
       print >> sys.stderr, ('Encountered %d failures (see above).' %
                             len(self._failures_encountered))
       sys.exit(1)
 
 
 # Object that rebaselines a JSON expectations file (not individual image files).
@@ skipping 221 matching lines @@
 parser.add_argument('--expectations-filename-output',
                     help=('filename (under EXPECTATIONS_ROOT) to write '
                           'updated expectations into; by default, overwrites '
                           'the input file (EXPECTATIONS_FILENAME)'),
                     default='')
 parser.add_argument('--expectations-root',
                     help=('root of expectations directory to update-- should '
                           'contain one or more builder subdirectories. '
                           'Defaults to %(default)s'),
                     default=os.path.join('expectations', 'gm'))
 parser.add_argument('--keep-going-on-failure', action='store_true',

[epoger, 2013/09/04 20:05:56]

For now, I'm going to keep the default as "halt immediately", because I think
most of the failures have been resolved now that we have expectations committed
for all platforms.

As we discussed... if we are still seeing errors much of the time, I will change
the default setting, at least temporarily.

                     help=('instead of halting at the first error encountered, '
                           'keep going and rebaseline as many tests as '
                           'possible, and then report the full set of errors '
                           'at the end'))
 parser.add_argument('--notes',
                     help=('free-form text notes to add to all updated '
                           'expectations'))
 # TODO(epoger): Add test that exercises --tests argument.
 parser.add_argument('--tests', metavar='TEST', nargs='+',
                     help=('which tests to rebaseline, e.g. '
@@ skipping 39 matching lines @@
     except:
       exception_handler.RaiseExceptionOrContinue()
   else:
     try:
       raise _InternalException('expectations_json_file %s not found' %
                                expectations_json_file)
     except:
       exception_handler.RaiseExceptionOrContinue()
 
 exception_handler.ReportAllFailures()