bump the semver tag of a git repo (using go 1.12+ style v4.1.3 tags)

git-bump

#!/bin/bash

bump=$1

if [ -z $bump ]; then
	echo "need to provide an action"
	exit 1
fi

tag=($(git describe --abbrev=0 --tags | perl -pe 's/^v?(\d+)\.(\d+)\.(\d+)$/\1 \2 \3/g'))

major=${tag[0]}
minor=${tag[1]}
patch=${tag[2]}

if [[ $bump == "major" ]]; then
	major=$((major+1))
	newtag="v$major.0.0"
elif [[ $bump == "minor" ]]; then
	minor=$((minor+1))
	newtag="v$major.$minor.0"
elif [[ $bump == "patch" ]]; then
	patch=$((patch+1))
	newtag="v$major.$minor.$patch"
else
	echo "unknown action '$bump'; must be one of major, minor, patch"
	exit 1
fi

git tag $newtag
git push --tags