If the cloned repo is shallow (e.g. like the default github actions
settings), the git describe command won't actually be able to fetch any
tags and will instead just get a hash. The resulting binary version
string will end up being that git hash. While it does tell you the exact
commit, it's not exactly helpful when wanting to know the general
version at a glance. For the case where we do have a git directory but
no available tags, build a version string using the mpv version + the
commit hash.
Fixes#15789.
After second thought version.py does not do anything useful. Meson has
built-in function vcs_tag that mostly replicate what version.py did. For
the build time we can just use __DATE__ and __TIME__. Of course this
changes time string format a little, but in my opinion it looks nicer in
fact.
Also it will use local time, instead UTC. But I would argue that date
string is only informative for users to check how old the specific mpv
build is. It doesn't have to be precise, it weren't for years anyway
before recent change.
Kacper Michajłow