Automatically prepend the JIRA issue-key to the commit message

prepare-commit-msg

#!/bin/sh

# Automatically prepend the JIRA issue-key to the commit message
readonly COMMIT_MESSAGE_PATH="$1"
readonly COMMIT_TYPE="$2"
readonly GIT_BRANCH=$(git branch --show-current)
# Pick the last issue key in a branch name or return empty result.
# - "feature/AB-123-is-not/the/AB-987-last" will yield "AB-987"
# - "main" will yield ""
readonly ISSUE_KEY=$(node -e 'console.log(process.argv.pop().split("/").reduce(((e,o)=>(o=/^[A-Z]{2,}-\d+/.exec(o)?.pop())?o:e),""))' "${GIT_BRANCH}")

# Don't change merge-commit messages
if [ "$COMMIT_TYPE" = "merge" ]; then
  exit
fi

if [ -z "$ISSUE_KEY" ]; then
  echo "$(tput setaf 3)warning$(tput sgr0) No issue key found in branch name $(tput bold)${GIT_BRANCH}$(tput sgr0)"
  exit
fi

# Issue key already prepended
if grep -q "^${ISSUE_KEY}\b" "$COMMIT_MESSAGE_PATH"; then
  exit
fi

# Issue key required; prepend to commit message
echo "$(tput setaf 4)info$(tput sgr0) Prepending commit message with issue key $(tput bold)${ISSUE_KEY}$(tput sgr0)"
sed -i -e "1s/^/${ISSUE_KEY}: /" "$COMMIT_MESSAGE_PATH"