How to automatically prepend git commit with a branch name

prepare-commit-msg.sh

#!/bin/bash

# JIRA branch name - JIRAPRJ-777-short-desc
# Prepended commit message - JIRAPRJ-777:<space>

# This way you can customize which branches should be skipped when
# prepending commit message. 
if [ -z "$BRANCHES_TO_SKIP" ]; then
  BRANCHES_TO_SKIP=(master develop test)
fi

BRANCH_NAME=$(git symbolic-ref --short HEAD)
BRANCH_NAME="${BRANCH_NAME##*/}"
BRANCH_NAME=$(echo $BRANCH_NAME | cut -d'-' -f1,2)

BRANCH_EXCLUDED=$(printf "%s\n" "${BRANCHES_TO_SKIP[@]}" | grep -c "^$BRANCH_NAME$")
BRANCH_IN_COMMIT=$(grep -c "$BRANCH_NAME\:" $1)

if [ -n "$BRANCH_NAME" ] && ! [[ $BRANCH_EXCLUDED -eq 1 ]] && ! [[ $BRANCH_IN_COMMIT -ge 1 ]]; then 
  sed -i.bak -e "1s/^/$BRANCH_NAME: /" $1
fi

Rename .git/hooks/prepare-commit-msg.sample to prepare-commit-msg, paste the script and make the file executable.

For instance with branch ARQ-653
$ git commit -m"Fixed bug"
will result with commit "ARQ-653: Fixed bug"