如何解决 git describe --match 限制

Question

I'm using git describe --long --tags to automatically generate version strings from repo tags. So that if I have 1.20 tag I get 1.20-5-g27ba6e8 version string in my code.

Now I'm only interested in tags which in regexish look like ^\\d+\\.\\d+$ (I don't want describe to see any other descriptive tags).

git describe has --match switch which would have been exactly what I need if not for the fact that the match is done using glob patterns.

How can I limit a glob pattern only to two numbers (which can have any number of digits!) delimited with a dot?

Answer 1

How can I limit a glob pattern only to two numbers (which can have any number of digits!) delimited with a dot?

You can't. The biggest problem is that glob patterns can't repreat last pattern one or more times, there is no + operator like in regex. The closest you can do is:

[0-9]*.[0-9]*

Sadly the * matches any characters. bash shell solves that issue by introducing extended glob, in the form of +([0-9]).+([0-9]) . But you can specify --match multiple times and generate patterns for all possible combinations (puff):

# generated with:
# p="[0-9] [0-9][0-9] [0-9][0-9][0-9]"; for i in $p; do for j in $p; do echo "--match \"$i.$j\""; done; done | paste -sd' '
# should handle up numbers up to 3 digits
git describe --long --tags --match "[0-9].[0-9]" --match "[0-9].[0-9][0-9]" --match "[0-9].[0-9][0-9][0-9]" --match "[0-9][0-9].[0-9]" --match "[0-9][0-9].[0-9][0-9]" --match "[0-9][0-9].[0-9][0-9][0-9]" --match "[0-9][0-9][0-9].[0-9]" --match "[0-9][0-9][0-9].[0-9][0-9]" --match "[0-9][0-9][0-9].[0-9][0-9][0-9]"

I also recommend to contribute to open source and implement something along --regexmatch to git describe . The other way round is to do the filtering by yourself and pass the tag back to git-describe to describe it. In POSIX shell that could be something along:

git tag --sort=committerdate | grep '^[0-9]\+\.[0-9]\+$' | tail -n1 | xargs git describe --long --tags --exact-match --match