homepage

https://travis-ci.com/github/python/cpython/jobs/383579366
Warning, treated as error:
/home/travis/build/python/cpython/Doc/library/string.rst:311:duplicate token description of format_spec, other instance in reference/lexical_analysis

There are two format_spec definitions:
"format_spec ::= [[fill]align][sign][#][0][width][grouping_option][.precision][type]"
https://docs.python.org/dev/library/string.html#format-specification-mini-language
"format_spec ::= (literal_char | NULL | replacement_field)*"
https://docs.python.org/dev/reference/lexical_analysis.html#formatted-string-literals 

I failed to reproduce the issue locally. I tried:
cd Doc
make clean
make venv PYTHON=../python 
./venv/bin/python -m pip install sphinx==2.2.0 blurb python-docs-theme
make check suspicious html SPHINXOPTS="-q -W -j4"

Oh. It seems like the warning only occurs randomly!? It is gone on one of my PR.

>>> sphinx.__version__
'3.2.1
I can reproduce this issue consistantly on my local machine with this environment.

Two issues about Sphinx 3.2.1 failing with "duplicate token description"
(posted on both)
#41760 'sign', multiple people nosy, failed where?
#41762 'format_spec', on Travis, PR by Victor Stinner (2.2.0 okay)

I closed bpo-41760 as a duplicate of this issue.

> I closed bpo-41760 as a duplicate of this issue.
The error message was different but similar:
Warning, treated as error:
/<<PKGBUILDDIR>>/Doc/library/string.rst:311:duplicate token description of sign, other instance in library/functions

".. productionlist::" markup is related to "Grammar production displays":
https://www.sphinx-doc.org/en/master/usage/restructuredtext/directives.html#grammar-production-displays
We can try to pass a different unique name to each ".. productionlist::" markup:
"The productionGroup argument to productionlist serves to distinguish different sets of production lists that belong to different grammars. Multiple production lists with the same productionGroup thus define rules in the same scope."

New changeset 8af239eacfcf52e4e0e2b0223e7cea4672309483 by Victor Stinner in branch 'master':
bpo-41762: Fix usage of productionlist markup in the doc (GH-22281)
https://github.com/python/cpython/commit/8af239eacfcf52e4e0e2b0223e7cea4672309483

New changeset c053402927d36f9f26160ded24999bf5109ea5eb by Miss Islington (bot) in branch '3.9':
bpo-41762: Fix usage of productionlist markup in the doc (GH-22281)
https://github.com/python/cpython/commit/c053402927d36f9f26160ded24999bf5109ea5eb

New changeset c5cddc17b5c046bb22072c1cf58b898c7ab92e07 by Miss Islington (bot) in branch '3.8':
bpo-41762: Fix usage of productionlist markup in the doc (GH-22281) (GH-22300)
https://github.com/python/cpython/commit/c5cddc17b5c046bb22072c1cf58b898c7ab92e07

I fixed the issue.
See bpo-35293 for deprecation warnings.

New changeset e5cc5fd89cc8855ad644ce4ba5e7de766313e418 by Łukasz Langa (Miss Islington (bot)) in branch '3.9':
bpo-41762: Fix usage of productionlist markup in the doc (GH-22281)
https://github.com/python/cpython/commit/e5cc5fd89cc8855ad644ce4ba5e7de766313e418