Release script (Create a release branch, build, merge it and automatically tag to a new version)

release.sh

#!/bin/zsh

LAST_VERSION=$(git tag -l | sort -t. -k 1,1n -k 2,2n -k 3,3n -k 4,4n | tail -n 1)
NEXT_VERSION=$(echo $LAST_VERSION | awk -F. -v OFS=. 'NF==1{print ++$NF}; NF>1{if(length($NF+1)>length($NF))$(NF-1)++; $NF=sprintf("%0*d", length($NF), ($NF+1)%(10^length($NF))); print}')
VERSION=${1-${NEXT_VERSION}}
DEFAULT_MESSAGE="Release"
MESSAGE=${2-${DEFAULT_MESSAGE}}
RELEASE_BRANCH="release/$VERSION"

git add .
git commit -am $MESSAGE
git push

# Create release branch
git checkout -b $RELEASE_BRANCH develop
gulp build
git add .
git commit -am "Build $NEXT_VERSION"
git push origin $RELEASE_BRANCH

# Merge release branch in master
git checkout master
git merge $RELEASE_BRANCH

# Merge release branch in develop
git checkout develop
git merge $RELEASE_BRANCH
git push origin develop

# Tag and push master
git checkout master
git tag $VERSION
git push origin master --tags

# Remove release branch
git branch -d $RELEASE_BRANCH

# Return to develop
git checkout develop