[MacPorts] #64045: py-pyzstd: tests fail from clean state because glob is used in global part of portfile

[MacPorts]

#64045: py-pyzstd: tests fail from clean state because glob is used in global part
of portfile
------------------------+-----------------------
 Reporter:  ryandesign  |      Owner:  catap
     Type:  defect      |     Status:  assigned
 Priority:  Normal      |  Milestone:
Component:  ports       |    Version:
 Keywords:              |       Port:  py-pyzstd
------------------------+-----------------------
 py-pyzstd does:

 {{{
     test.env        PYTHONPATH=[glob -nocomplain
 ${worksrcpath}/build/lib*]
 }}}

 This won't work if the port is in a clean state at the time the portfile
 is parsed because ${worksrcpath} and its contents don't exist yet.

 For example: `sudo port clean py39-pyzstd && sudo port test py39-pyzstd`
 fails:

 {{{
 :info:test test_zstd (unittest.loader._FailedTest) ... ERROR
 :info:test
 ======================================================================
 :info:test ERROR: test_zstd (unittest.loader._FailedTest)
 :info:test
 ----------------------------------------------------------------------
 :info:test ImportError: Failed to import test module: test_zstd
 :info:test Traceback (most recent call last):
 :info:test   File
 "/opt/local/Library/Frameworks/Python.framework/Versions/3.9/lib/python3.9/unittest/loader.py",
 line 154, in loadTestsFromName
 :info:test     module = __import__(module_name)
 :info:test   File "/opt/local/var/macports/build
 /_Users_rschmidt_macports_macports-ports-ryandesign-fork_python_py-
 pyzstd/py39-pyzstd/work/pyzstd-0.15.0/tests/test_zstd.py", line 20, in
 <module>
 :info:test     import pyzstd
 :info:test ModuleNotFoundError: No module named 'pyzstd'
 :info:test
 ----------------------------------------------------------------------
 }}}

 A subsequent `sudo port test py39-pyzstd` without cleaning first succeeds.

 To avoid this problem, if you need to `glob` or otherwise inspect the
 contents of ${worksrcpath}, you can't do it in the global part of the
 portfile. You have to defer it to a time when ${worksrcpath} exists. In
 this case, you should enclose at least the `test.env` line in a `pre-test`
 block.

-- 
Ticket URL: <https://trac.macports.org/ticket/64045>
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