Git Auto Increment tag

README.md

Source: https://whatthepatch.blogspot.com/2017/06/git-auto-increment-tag.html

gittag.sh

#!/bin/bash

IS_MAJOR=$(git log -n 1 | grep -i break || true)
IS_MINOR=$(git log -n 1 | grep -i minor || true)

if [[ -n "$IS_MINOR" ]]; then
  echo "found minor in commit message. will increment minor version"
  BUMP_MODE="minor"
elif [[ -n "$IS_MAJOR" ]]; then
  echo "found breaking in the commit message. will increment major version"
  BUMP_MODE="major"
else
  echo "no version mode specified, defaulting to patch"
  BUMP_MODE="patch"
fi

# Get the latest tag
VERSION=$(git describe --match "v[0-9]*" --abbrev=0 --tags)
# If no tag, give VERSION a default value of 0
VERSION=${VERSION:-'v0.0.0'}

# Remove the prefix "v"
CLEANED_VERSION=(${VERSION//v/})

MAJOR="${CLEANED_VERSION%%.*}"
CLEANED_VERSION="${CLEANED_VERSION#*.}"
MINOR="${CLEANED_VERSION%%.*}"
CLEANED_VERSION="${CLEANED_VERSION#*.}"
PATCH="${CLEANED_VERSION%%.*}"
CLEANED_VERSION="${CLEANED_VERSION#*.}"

case $BUMP_MODE in
"major")
  MAJOR=$((MAJOR + 1))
  MINOR=0
  PATCH=0
  ;;
"minor")
  MINOR=$((MINOR + 1))
  PATCH=0
  ;;
"patch")
  PATCH=$((PATCH + 1))
  ;;
esac

# Create new tag
NEW_TAG="v$MAJOR.$MINOR.$PATCH"
echo "Last tag version $VERSION New tag will be $NEW_TAG"

# Get current hash and see if it already has a tag
GIT_COMMIT=$(git rev-parse HEAD)
NEEDS_TAG=$(git describe --contains "$GIT_COMMIT" 2>/dev/null)

echo "###############################################################"
# Only tag if no tag already (would be better if the git describe command above could have a silent option)
if [[ -z "$NEEDS_TAG" ]]; then
  echo "Tagged with $NEW_TAG (Ignoring fatal:cannot describe - this means commit is untagged) "
  git tag -a $NEW_TAG -m "auto bump $BUMP_MODE version 🚀"
  git push origin --tags
else
  echo "Current commit already has a tag $VERSION"
fi
echo "###############################################################"