bash script to generate changelog focused for Drupal modules

changelog.sh

#!/bin/bash
# Author: Luigi Guevara <@killua99>
#
# Use
# For a Simple Tag changelog
# ./changelog > CHANGELOG.txt
#
# For a current dev branch with the old tag log
# ./changelog 7.x-2.x > CHANGELOG.txt

MODULE_NAME=`grep -oP 'name\s*=\s*.*' *.info | grep -oP '[^name\s*=\s*].*'`
CURRENT_BRANCH=$1

echo "CHANGELOG: $MODULE_NAME"
echo -----------------------------
if [ $CURRENT_BRANCH ]; then
  echo
  echo "[$CURRENT_BRANCH xxxx-xx-xx] (Dev branch)"
  echo
  LOG=$(git log --no-merges --format=' - %w(75,0,3)%s' $CURRENT_BRANCH)
  echo "$LOG"
fi

git for-each-ref --shell --sort='-authordate' --format="tag=%(refname:short) date=%(authordate:short)" refs/tags | \
  while read ENTRY
  do
    eval $ENTRY
    LOG=$(git log --no-merges --format=" - %w(75,0,3)%s" $tag)
    echo
    echo "[$tag - $date]"
    echo
    echo "$LOG"
  done