Add job prefix to error messages.

Add job prefix to error messages.

BUG=235289
R=maruel@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=202236

[M-A Ruel, 2013-05-24 22:25:56]

https://codereview.chromium.org/15792004/diff/1/gclient_utils.py
File gclient_utils.py (right):

https://codereview.chromium.org/15792004/diff/1/gclient_utils.py#newcode28
gclient_utils.py:28: msg = '\n'.join(['%d>_____ %s' % (index, l) for l in
msg.splitlines()])
I like the idea but two things:
- A generator is sufficient, no need to construct an intermediary list.
- I'd prefer '%d> %s'

https://codereview.chromium.org/15792004/diff/1/gclient_utils.py#newcode29
gclient_utils.py:29: Exception.__init__(self, msg, *args, **kwargs)
I think super() works here. The old-style class problem is mostly an issue with
buildbot code.

[szager1, 2013-05-24 22:48:16]

https://codereview.chromium.org/15792004/diff/1/gclient_utils.py
File gclient_utils.py (right):

https://codereview.chromium.org/15792004/diff/1/gclient_utils.py#newcode28
gclient_utils.py:28: msg = '\n'.join(['%d>_____ %s' % (index, l) for l in
msg.splitlines()])
On 2013/05/24 22:25:56, Marc-Antoine Ruel wrote:
> I like the idea but two things:
> - A generator is sufficient, no need to construct an intermediary list.
> - I'd prefer '%d> %s'

I changed the format.  As for using a generator -- that's some pretty intense
pre-optimization at the expense of terseness, doncha think?  Is this what you
had in mind:

if index:
  new_msg = ''
  for l in msg.splitlines():
    new_msg += '%d> %s\n' % (index, l)
  msg = new_msg

?

https://codereview.chromium.org/15792004/diff/1/gclient_utils.py#newcode29
gclient_utils.py:29: Exception.__init__(self, msg, *args, **kwargs)
On 2013/05/24 22:25:56, Marc-Antoine Ruel wrote:
> I think super() works here. The old-style class problem is mostly an issue
with
> buildbot code.

Done.

[M-A Ruel, 2013-05-24 22:59:20]

https://codereview.chromium.org/15792004/diff/1/gclient_utils.py
File gclient_utils.py (right):

https://codereview.chromium.org/15792004/diff/1/gclient_utils.py#newcode28
gclient_utils.py:28: msg = '\n'.join(['%d>_____ %s' % (index, l) for l in
msg.splitlines()])
On 2013/05/24 22:48:16, szager1 wrote:
> On 2013/05/24 22:25:56, Marc-Antoine Ruel wrote:
> > I like the idea but two things:
> > - A generator is sufficient, no need to construct an intermediary list.
> I changed the format.  As for using a generator -- that's some pretty intense
> pre-optimization at the expense of terseness, doncha think?

You misunderstood. I meant removing the brackets, they are not needed. E.g.:
msg = '\n'.join('%d> %s' % (index, l) for l in msg.splitlines())

[szager1, 2013-05-24 23:01:54]

On 2013/05/24 22:59:20, Marc-Antoine Ruel wrote:

> You misunderstood. I meant removing the brackets, they are not needed. E.g.:
> msg = '\n'.join('%d> %s' % (index, l) for l in msg.splitlines())

Oh, that makes sense.

Done.

[M-A Ruel, 2013-05-24 23:15:51]

lgtm

The first example of pep 289 explains the rationale.
http://www.python.org/dev/peps/pep-0289/

[szager1, 2013-05-24 23:59:32]

Committed patchset #3 manually as r202236.