"no such group" error in buglink plugin

[klibby]

Rust, rustfmt, and servo have all thrown the following error (eg https://jenkins-dxr.mozilla.org/job/servo/9/console):

15:21:29 A worker failed while indexing /builds/dxr-build-env/src/servo/servo/tests/wpt/css-tests/css21_dev/html4/border-bottom-applies-to-009.htm:
15:21:29 Traceback (most recent call last):
15:21:29 File "/builds/dxr-build-env/dxr/dxr/build.py", line 572, in index_chunk
15:21:29 index_file(tree, tree_indexers, path, es, index)
15:21:29 File "/builds/dxr-build-env/dxr/dxr/build.py", line 542, in index_file
15:21:29 for chunk in bulk_chunks(docs(), docs_per_chunk=300, bytes_per_chunk=10000):
15:21:29 File "/builds/dxr-build-env/venv/local/lib/python2.7/site-packages/pyelasticsearch/utils.py", line 31, in bulk_chunks
15:21:29 for action in actions:
15:21:29 File "/builds/dxr-build-env/dxr/dxr/build.py", line 514, in docs
15:21:29 chain.from_iterable(regionses)))):
15:21:29 File "/builds/dxr-build-env/dxr/dxr/lines.py", line 472, in finished_tags
15:21:29 key=nesting_order)
15:21:29 File "/builds/dxr-build-env/dxr/dxr/lines.py", line 338, in tag_boundaries
15:21:29 for start, end, data in tags:
15:21:29 File "/builds/dxr-build-env/dxr/dxr/plugins/buglink/init.py", line 15, in refs
15:21:29 bug = m.group(1)
15:21:29 IndexError: no such group

[erikrose]

Hmm, my initial guess is that configobj is reading #([0-9]+) as a comment, so the regex is empty, so it has no capturing groups.

[pelmers]

d'oh, that behavior was really puzzling me...

[erikrose]

Yep, confirmed.

[erikrose]

Put double quotes around it, and the problem goes away.

[erikrose]

Better still, use triple-double quotes to avoid DiffSK/configobj#97, which kicks in in some situations:

"""#([0-9]+)"""

[erikrose]

Looks like I did document this way back when: https://dxr.readthedocs.io/en/latest/configuration.html#syntax. Too bad configobj development has stalled.