rebaseline.py: error out early if --expectations-root not pointing at gm-expected dir

rebaseline.py: error out early if --expectations-root not pointing at gm-expected dir
BUG=https://code.google.com/p/skia/issues/detail?id=1403
R=senorblanco@chromium.org

Committed: https://code.google.com/p/skia/source/detail?r=9961

[epoger, 2013-07-10 16:24:03]

https://codereview.chromium.org/18416005/diff/1/tools/rebaseline.py
File tools/rebaseline.py (left):

https://codereview.chromium.org/18416005/diff/1/tools/rebaseline.py#oldcode192
tools/rebaseline.py:192: print ('Skipped these tests due to test/config filters:
%s' %
I deleted this output while I was at it... it seemed like it was unnecessarily
verbose.

[epoger, 2013-07-10 16:28:39]

Ready for review at patchset 2.

https://codereview.chromium.org/18416005/diff/3001/tools/tests/rebaseline/out...
File tools/tests/rebaseline/output/exercise-bug1403/output-expected/stdout
(right):

https://codereview.chromium.org/18416005/diff/3001/tools/tests/rebaseline/out...
tools/tests/rebaseline/output/exercise-bug1403/output-expected/stdout:6:
Exception: Could not find "base-android-galaxy-nexus" subdir within
expectations_root "tools/tests/rebaseline/input".  Are you sure
--expectations-root is pointing at a valid gm-expected directory?
Since this test case sets --expecations-root to a directory without the expected
platform subdirs, it fails right away with a helpful error message.

[Stephen White, 2013-07-10 16:47:36]

LGTM

https://codereview.chromium.org/18416005/diff/3001/tools/tests/rebaseline/out...
File tools/tests/rebaseline/output/exercise-bug1403/output-expected/stdout
(right):

https://codereview.chromium.org/18416005/diff/3001/tools/tests/rebaseline/out...
tools/tests/rebaseline/output/exercise-bug1403/output-expected/stdout:6:
Exception: Could not find "base-android-galaxy-nexus" subdir within
expectations_root "tools/tests/rebaseline/input".  Are you sure
--expectations-root is pointing at a valid gm-expected directory?
On 2013/07/10 16:28:39, epoger wrote:
> Since this test case sets --expecations-root to a directory without the
expected
> platform subdirs, it fails right away with a helpful error message.

More a design question, but should we actually be providing tracebacks in this
case, or just catching the exception at the top level and printing an error
message?

[epoger, 2013-07-10 16:53:33]

https://codereview.chromium.org/18416005/diff/3001/tools/tests/rebaseline/out...
File tools/tests/rebaseline/output/exercise-bug1403/output-expected/stdout
(right):

https://codereview.chromium.org/18416005/diff/3001/tools/tests/rebaseline/out...
tools/tests/rebaseline/output/exercise-bug1403/output-expected/stdout:6:
Exception: Could not find "base-android-galaxy-nexus" subdir within
expectations_root "tools/tests/rebaseline/input".  Are you sure
--expectations-root is pointing at a valid gm-expected directory?
On 2013/07/10 16:47:36, Stephen White wrote:
> On 2013/07/10 16:28:39, epoger wrote:
> > Since this test case sets --expecations-root to a directory without the
> expected
> > platform subdirs, it fails right away with a helpful error message.
> 
> More a design question, but should we actually be providing tracebacks in this
> case, or just catching the exception at the top level and printing an error
> message?

Advantages of printing the stack trace:
- gives you more info

Disadvantages:
- would be confusing to mortals (but woe be to mortals running rebaseline.py)
- more output that changes in the tool self-tests

I think I'll leave it as-is for now, but I wouldn't be opposed to changing it.

[epoger, 2013-07-10 16:54:14]

Committed patchset #2 manually as r9961 (presubmit successful).

[epoger, 2013-07-10 17:14:27]

https://codereview.chromium.org/18416005/diff/3001/tools/tests/rebaseline/out...
File tools/tests/rebaseline/output/exercise-bug1403/output-expected/stdout
(right):

https://codereview.chromium.org/18416005/diff/3001/tools/tests/rebaseline/out...
tools/tests/rebaseline/output/exercise-bug1403/output-expected/stdout:6:
Exception: Could not find "base-android-galaxy-nexus" subdir within
expectations_root "tools/tests/rebaseline/input".  Are you sure
--expectations-root is pointing at a valid gm-expected directory?
On 2013/07/10 16:53:34, epoger wrote:
> On 2013/07/10 16:47:36, Stephen White wrote:
> > On 2013/07/10 16:28:39, epoger wrote:
> > > Since this test case sets --expecations-root to a directory without the
> > expected
> > > platform subdirs, it fails right away with a helpful error message.
> > 
> > More a design question, but should we actually be providing tracebacks in
this
> > case, or just catching the exception at the top level and printing an error
> > message?
> 
> Advantages of printing the stack trace:
> - gives you more info
> 
> Disadvantages:
> - would be confusing to mortals (but woe be to mortals running rebaseline.py)
> - more output that changes in the tool self-tests
> 
> I think I'll leave it as-is for now, but I wouldn't be opposed to changing it.

Disadvantage of printing the stack trace: the stack trace shows up differently
on the bot, so this CL broke the Housekeeper-PerCommit build.

http://108.170.217.252:10117/builders/Housekeeper-PerCommit/builds/752/steps/...

I'll change it to just print out the error message, not the whole stack trace.
:-)

[epoger, 2013-07-10 17:24:26]

On 2013/07/10 17:14:27, epoger wrote:
>
https://codereview.chromium.org/18416005/diff/3001/tools/tests/rebaseline/out...
> File tools/tests/rebaseline/output/exercise-bug1403/output-expected/stdout
> (right):
> 
>
https://codereview.chromium.org/18416005/diff/3001/tools/tests/rebaseline/out...
> tools/tests/rebaseline/output/exercise-bug1403/output-expected/stdout:6:
> Exception: Could not find "base-android-galaxy-nexus" subdir within
> expectations_root "tools/tests/rebaseline/input".  Are you sure
> --expectations-root is pointing at a valid gm-expected directory?
> On 2013/07/10 16:53:34, epoger wrote:
> > On 2013/07/10 16:47:36, Stephen White wrote:
> > > On 2013/07/10 16:28:39, epoger wrote:
> > > > Since this test case sets --expecations-root to a directory without the
> > > expected
> > > > platform subdirs, it fails right away with a helpful error message.
> > > 
> > > More a design question, but should we actually be providing tracebacks in
> this
> > > case, or just catching the exception at the top level and printing an
error
> > > message?
> > 
> > Advantages of printing the stack trace:
> > - gives you more info
> > 
> > Disadvantages:
> > - would be confusing to mortals (but woe be to mortals running
rebaseline.py)
> > - more output that changes in the tool self-tests
> > 
> > I think I'll leave it as-is for now, but I wouldn't be opposed to changing
it.
> 
> Disadvantage of printing the stack trace: the stack trace shows up differently
> on the bot, so this CL broke the Housekeeper-PerCommit build.
> 
>
http://108.170.217.252:10117/builders/Housekeeper-PerCommit/builds/752/steps/...
> 
> I'll change it to just print out the error message, not the whole stack trace.
> :-)

Fixed in https://code.google.com/p/skia/source/detail?r=9965