Sphinx can't find asdl.py when not started from the Doc/ directory

[JulienPalard]

BPO	41331
Nosy	@JulienPalard, @isidentical
PRs	bpo-41331: Doc: fix import of asdl.py when called from outside Doc/. #21529

^{Note: these values reflect the state of the issue at the time it was migrated and might not reflect the current state.}

Show more details

GitHub fields:

assignee = 'https://github.com/JulienPalard'
closed_at = <Date 2020-07-21.05:54:50.195>
created_at = <Date 2020-07-18.08:26:35.805>
labels = ['3.9', '3.10', 'docs']
title = "Sphinx can't find asdl.py when not started from the Doc/ directory"
updated_at = <Date 2020-07-21.05:54:50.194>
user = 'https://github.com/JulienPalard'

bugs.python.org fields:

activity = <Date 2020-07-21.05:54:50.194>
actor = 'mdk'
assignee = 'mdk'
closed = True
closed_date = <Date 2020-07-21.05:54:50.195>
closer = 'mdk'
components = ['Documentation']
creation = <Date 2020-07-18.08:26:35.805>
creator = 'mdk'
dependencies = []
files = []
hgrepos = []
issue_num = 41331
keywords = ['patch']
message_count = 1.0
messages = ['373888']
nosy_count = 2.0
nosy_names = ['mdk', 'BTaskaya']
pr_nums = ['21529']
priority = 'normal'
resolution = 'fixed'
stage = 'resolved'
status = 'closed'
superseder = None
type = None
url = 'https://bugs.python.org/issue41331'
versions = ['Python 3.9', 'Python 3.10']

[JulienPalard]

When running the following command from the Doc/ directory:

./venv/bin/sphinx-build -Q -b gettext -D gettext_compact=0 . ../pot/

everything goes right, but when running the following from cpython direcory:

./Doc/venv/bin/sphinx-build -Q -b gettext -D gettext_compact=0 Doc pot

we get:

Extension error:
Could not import extension asdl_highlight (exception: No module named 'asdl')

This is because sys.path.append(os.path.abspath("../Parser/")) starts from the current directory, cpython/../Parser don't exists while Doc/../Parser exists.

It could be fixed by starting with a Path(file).resolve(), will PR it.