Arch Linux

pacman 4.2.0-6

As described in "VCS package guidelines",
https://wiki.archlinux.org/index.php/VCS_package_guidelines

there are very specific recommendations for automatic versioning, covering Git, Subversion, Mercurial, Bazaar, and a fallback, based upon date. To establish a uniform versioning scheme for VCS packages, these recommendations should be incorporated into pacman, to be applied automatically, as defaults, based upon the VCS type. People could still over-ride these defaults with an explicit pkgver() function in the PKGBUILD, but otherwise, there is no reason to engage in "busywork", copying these pkgver() recommendations from the "VCS package guidelines".