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Bug 1959007 - python-libcst fails to build with Python 3.10: AST changes make tests fail [built without tests]
Summary: python-libcst fails to build with Python 3.10: AST changes make tests fail [b...
Status: NEW
Alias: None
Product: Fedora
Classification: Fedora
Component: python-libcst
Version: rawhide
Hardware: Unspecified
OS: Unspecified
Target Milestone: ---
Assignee: Davide Cavalca
QA Contact:
Depends On:
Blocks: PYTHON3.10 1969002
TreeView+ depends on / blocked
Reported: 2021-05-10 14:50 UTC by Miro Hrončok
Modified: 2021-06-14 10:23 UTC (History)
3 users (show)

Fixed In Version:
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Clone Of:
Last Closed:
Type: Bug

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Description Miro Hrončok 2021-05-10 14:50:47 UTC
python-libcst fails to build with Python 3.10.0b1.

FAILED libcst/_nodes/tests/ - Asserti...
FAILED libcst/tests/ - Asse...
FAILED libcst/tests/ - ...
FAILED libcst/tests/
FAILED libcst/tests/

The failures seem like differences in AST.

For the build logs, see:

For all our attempts to build python-libcst with Python 3.10, see:

Testing and mass rebuild of packages is happening in copr. You can follow these instructions to test locally in mock if your package builds with Python 3.10:

Let us know here if you have any questions.

Python 3.10 will be included in Fedora 35. To make that update smoother, we're building Fedora packages with early pre-releases of Python 3.10.
A build failure prevents us from testing all dependent packages (transitive [Build]Requires), so if this package is required a lot, it's important for us to get it fixed soon.
We'd appreciate help from the people who know this package best, but if you don't want to work on this now, let us know so we can try to work around it on our side.

Comment 1 Miro Hrončok 2021-06-04 20:12:54 UTC
This is a mass-posted update. Sorry if it is not 100% accurate to this bugzilla.

The Python 3.10 rebuild is in progress in a Koji side tag. If you manage to fix the problem, please commit the fix in the rawhide branch, but don't build the package in regular rawhide.

You can either build the package in the side tag, with:

    $ fedpkg build --target=f35-python

Or you can the build and we will eventually build it for you.

Note that the rebuild is still in progress, so not all (build) dependencies of this package might be available right away.


See also

If you have general questions about the rebuild, please use this mailing list thread:

Comment 2 Miro Hrončok 2021-06-07 22:57:52 UTC
The f35-python side tag has been merged to Rawhide. From now on, build as you would normally build.

Comment 3 Davide Cavalca 2021-06-08 21:24:03 UTC
Put up to see if the new version works any better

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