github-format-pull-request

#!/bin/bash

set -e

usage() {
  cat >&2 <<EOF
usage: $0 RANGE

Use this script to generate GitHub-pastable pull request descrition
from your last commits. Example:

### This is commit title number 1

This is commit description.

---

### Update README

---

### Replace deprecated sysctl() by write to /proc/sys

As the manual says: "Do not use this system call"
EOF
  exit 1
}

if [ $# -lt 1 ]; then
  # Find the "master" branch (usually master)
  git rev-parse --verify master &>/dev/null && branch=master ||
    { git rev-parse --verify devel &>/dev/null && branch=devel; } ||
      usage
  range="$(git merge-base $branch HEAD)..HEAD"
elif [ $# -eq 1 ] && [ ! -z "${1##*[!0-9]*}" ]; then
  # show N last commits
  range="HEAD~$1..HEAD"
elif [ $# -eq 1 ] && git log "$1" &>/dev/null; then
  # show RANGE, e.g. f7e2b61..2ad187f
  range="$1"
else
  usage
fi

git log --reverse "$range" \
  | sed 's/^commit .*$/---/' \
  | sed '/^[^ \-]/d' \
  | sed 's/^    //' \
  | sed ':a;N;$!ba;s/---\n\n/---\n\n### /g' \
  | tail -n +3