setuptools scm workaround doesnt work for packages with dashes in the name

[RonnyPfannschmidt]

the fix of #68 doesn't notify the user that it uses pretend_version,, and incorrectly puts in a bad version number

this triggers pypa/setuptools_scm#630

as https://github.com/zobayer1/logging-extras has in fact a extra dash

its ABSOLUTELY necessary to inform the users if something like SETUPTOOLS_SCM_PRETEND_VERSION is set
additionally its not safe to use for build processes that actually install dependencies (as any pulled sdist that wants setuptools_scm may get misinformed about their versions

check-manifest/check_manifest.py

Lines 877 to 882 in 7c4403a

	def extract_version_from_filename(filename):
	"""Extract version number from sdist filename."""
	filename = os.path.splitext(os.path.basename(filename))[0]
	if filename.endswith('.tar'):
	filename = os.path.splitext(filename)[0]
	return filename.partition('-')[2]

incorrctly extract

and then

check-manifest/check_manifest.py

Line 977 in 7c4403a

os.environ['SETUPTOOLS_SCM_PRETEND_VERSION'] = version

always replaces without a warning (so people cant even fix it with a env var)

[zobayer1]

I faced pypa/setuptools_scm#630 only recently. However, @RonnyPfannschmidt made a quick investigation that led me here. I am not sure whether a dash should or should not be part of a source distribution name, but it seems to be a fairly common practice to use dashes in the name. In fact, the same is done in check-manifest itself.

check-manifest/setup.py

Line 29 in 7c4403a

name='check-manifest',

As pointed out above, the code here assumes that there would not be any dashes in the file name.

check-manifest/check_manifest.py

Line 882 in 7c4403a

return filename.partition('-')[2]

Knowing that setuptools version strings do not contain extra dashes, this could be replaced with the following

    return filename.split('-')[-1]

I have tested a build containing this change with my setup, and the tests provided with this repo. It is working as expected now.

Was there a specific reason or motivation to use the partition method there? Were there any special cases that split would not be able to handle?

[mgedmin]

Should be fixed by #146.

[mgedmin]

Fix released in check-manifest 0.47.