UserWarning: tag '0.0' no version found in a fresh Git repo when tag_regex is defined #804
Description
Trying to use setuptools_scm==7.1.0 on a brand new repository with no tags fails if tag_regex has been specified that does not match the default fallback version 0.0, like the example below:
^(?P<prefix>packagename[-_])(?P<version>[vV]?\d+(?:\.\d+){0,2}[^\+]*)(?:\+.*)?$After a little troubleshooting and inspecting the source code, the problem seems to be that if no tags are found in the parent git repo matching the provided regex, setuptools_scm.git._git_parse_inner attempts to fake a tag 0.0 to provide to setuptools_scm.version.meta as a default.
This later causes a panic when setuptools_scm.version.tag_to_version attempts to match 0.0 against the configured regular expression and returns None.
For context, I'm trying to introduce setuptools_scm to a pre-existing monorepo containing multiple Python projects that need to be individually versioned. As such, I can't use an optional prefix as tags without a prefix would have a chance to override the version of every package in the repository.