AttributeError: module 'gast' has no attribute 'MatchStar', when gast < 0.5.4 installed

[tommilligan]

Found during a source build of an old version of scipy, which uses beniget transitively during the build process. Installed packages were:

======== Resolution Result ========
Stable pins:
              python None
               numpy 1.23.2
              cython 0.29.37
            pybind11 2.10.4
             pythran 0.12.2
        meson-python 0.16.0
               wheel 0.37.1
             beniget 0.4.2.post1
                gast 0.5.3
               meson 1.4.1
           packaging 24.1
                 ply 3.11
  pyproject-metadata 0.8.0

The traceback seen is:

  File "/tmp/pdm-build-env-hi55zv05-shared/lib/python3.11/site-packages/beniget/beniget.py", line 112, in name
    elif isinstance(self.node, (ast.MatchStar, ast.MatchAs)):
                                ^^^^^^^^^^^^^
AttributeError: module 'gast' has no attribute 'MatchStar'

gast looks to have added support for MatchStar in 0.5.4: serge-sans-paille/gast@0.5.3...0.5.4#diff-44b67094998a7df1e5ce843b5a2faa44950f5896ac9e07ab99d09e2b24c90143R328

However, beniget still only requires gast>0.5.0:

beniget/requirements.txt

Line 1 in 40d3954

gast >= 0.5.0

I think that either requirements.txt should be bumped to indicate a higher version of gast is required, or documentation should be added that a certain level of gast is required for newer python features like the match statement.

I worked around my specific case by upgrading other packages that were causing gast 0.5.3 to be installed, so we no longer hit this case.