commit-msg

commit-msg

#!/bin/bash

BRANCH_PATH=$(git symbolic-ref -q HEAD) # Something like refs/heads/my-branch-name
BRANCH_NAME=${BRANCH_PATH##*/} # Get text behind the last / of the branch path
# Make sure we have an issue number in front before doing anything
if [[ $BRANCH_NAME =~ (^[0-9]{4}) ]] ;then
  ISSUE_NUMBER=${BASH_REMATCH[1]}
  FIRST_LINE=$(head -n1 $1)

  # make sure there isn't already a "fixes ISSUE_NUMBER" line in message (ex. if it's an amend)
  ISSUE_NUM_RE="[Ff]ixes #[0-9]{4}"
  if ! [[ "$(cat $1)" =~ $ISSUE_NUM_RE ]] ;then
    cat "$1" > /tmp/out && mv /tmp/out "$1"
    echo -ne "\nfixes #$ISSUE_NUMBER" >> "$1"
  fi

fi

ISSUE_NUM_RE needs to be a variable. Everything after # will be evaluated as a comment if that expression isn't surrounded by quotes, and newer bash versions handle quotes a bit strangely. See this SO answer.