git-cherry-copy

#!/usr/bin/env bash
#
# git-cherry-copy
#
# License: MIT
# Copyright (c) 2012 Lennart C. L. Kats

set -e

STASH=
CURRENTBRANCH=`git-get-branch`
MASTER=origin/master
MAKENEWBRANCH=
MAKE_NEW=
NO_FETCH=
MOVE_BRANCH=
PULL_REQUEST=
ORIGINAL_COMMAND="`basename $0` $*"

while echo "$1" | grep -E "-" >/dev/null; do
  case "$1" in
    -b)
      MAKE_NEW=-b ;;
    -f)
      NO_FETCH=-f ;;
    -m)
      MOVE_BRANCH=-m ;;
    -p)
      PULL_REQUEST=-p ;;
    *)
      break ;;
  esac
  shift
done

if echo "$1" | grep origin/ >/dev/null; then
  MASTER=$1
  shift
fi

BRANCH=$1
shift

if [ "`git branch --list $BRANCH 2>/dev/null`" == "" ]; then
  if [ ! $MAKE_NEW ]; then
    echo Branch $BRANCH does not exist and option -b not specified. Aborting. >&2
    exit 1
  fi
elif [ $MAKE_NEW ]; then
  echo Branch $BRANCH already exists and option -b specified. Aborting. >&2
  exit 1
fi
if [ "$1" == "" ]; then
  echo "Error: no commits to cherry-pick specified" >&2
  if [ "`git status --porcelain | grep -Ev '\?+ '`" != "" ]; then
    echo "Tip: did you mean to move your uncommited changes? Try: $ORIGINAL_COMMAND LOCAL" >&2
  fi
  echo Aborting. >&2
  exit 1
fi

if [ "$BRANCH" == "" ] || [ "$BRANCH" == "--help" ]; then
  echo "Usage: `basename $0` [OPTIONS...] [<origin/BRANCH>] <BRANCH> <CHERRY.. | LOCAL>"
  echo '  -b              create a new branch BRANCH, rather than use an existing one'
  echo '  -f              disable fetch step'
  echo '  -p              make a pull request for the created branch'
  # echo '  -m`             move the commit(s), instead of copying it'
  echo '  origin/BRANCH   name for base branch'
  echo '  BRANCH          name for new branch'
  echo "  CHERRY          a commit, a branch to pick the head from, or a range of commits [default: $CURRENTBRANCH]"
  echo "  LOCAL           take uncommited changes instead of a range of commits"
  exit
fi

if [ "$1" == local ] || [ "$1" == LOCAL ]; then
  echo '$ git stash'
  RESULT=`git stash save "changes stashed by git-branch-from-cherry"`
  if echo "$RESULT" | grep -iE 'No local changes' >/dev/null; then
    echo -e "error: no local changes. Aborting.">&2
    exit 1
  fi
  echo
fi

# -m is very conservative and only supports a few cases
if [ "$MOVE_BRANCH" ]; then
  if [ "$*" == "local" ] || [ "$*" == LOCAL ]; then
    MOVE_BRANCH=
  elif echo "$*" | grep -Ei '^ (HEAD\^\^|HEAD~2) (HEAD\^|HEAD~1) HEAD$' >/dev/null; then
    MOVE_BRANCH="git reset --hard HEAD^^^"
  elif echo "$*" | grep -Ei '^(HEAD\^|HEAD~1) HEAD$' >/dev/null; then
    MOVE_BRANCH="git reset --hard HEAD^^"
  elif echo "$*" | grep -Ei '^HEAD$' >/dev/null || [ "`git rev-parse $*`" == "`git rev-parse HEAD`" ] ||
       [ "$*" == "" ]; then
    MOVE_BRANCH="git reset --hard HEAD^"
  else
    echo "error: cannot use -m with this cherry-pick pattern. Aborting." >&2
    exit 1
  fi
fi

if [ ! $NO_FETCH ] && [ $MAKE_NEW ]; then
  M=`echo $MASTER | perl -pe 's/^origin\/(.*)/$1/'`
  echo "$ git fetch origin $M"
  git fetch -q origin $M
  echo
fi

if [ "$1" == local ] || [ "$1" == LOCAL ]; then
  if [ $MAKE_NEW ]; then
    echo "$ git checkout $MASTER"
    git checkout -q $MASTER 
    echo
  fi
  echo "$ git checkout $MAKE_NEW $BRANCH"
  git checkout -q $MAKE_NEW $BRANCH
  echo
  echo "$ git stash pop"
  git stash pop -q
  echo
  echo "$ git status -s"
  git status -s
  exit
else
  CHERRY=`git rev-parse "$@"`
  if [ $# == 1 ]; then
    echo "$ git log --oneline --first-parent -1 $@"
    git --no-pager log --oneline --color=never --first-parent -1 `git rev-parse "$@"`
    echo
  #else
  #  echo "(can't show revision log for multiple revisions)"
  fi
fi

RESULT=`git stash save "changes stashed by git-branch-from-cherry"`
if ! echo "$RESULT" | grep -iE 'No local changes' >/dev/null; then
  echo '$ git stash'
  echo
  STASH=1
fi

if [ $MAKE_NEW ]; then
  echo "$ git checkout $MASTER"
  git checkout -q $MASTER
  echo
fi

if ! ls `pwd` &>/dev/null; then
  PREVPWD=`pwd`
  while [ ! -e .git ] && [ "`pwd`" != "/" ]; do
    cd ..
  done
  echo "$ git checkout $CURRENTBRANCH"
  git checkout -q $CURRENTBRANCH
  echo
  if [ $STASH ]; then
     echo '$ git stash pop'
     git stash pop -q
     echo
  fi
  echo "error: cannot execute this from directory `pwd` that only exists in the curent branch. Aborted."
  cd $PREVPWD
  exit 1
fi

echo "$ git checkout $BRANCH"
git checkout -q $MAKE_NEW $BRANCH
echo

echo "$ git cherry-pick $CHERRY"
git cherry-pick $CHERRY
echo

echo "$ git checkout $CURRENTBRANCH"
git checkout -q $CURRENTBRANCH
echo

if [ "$MOVE_BRANCH" ]; then
  echo "$ $MOVE_BRANCH"
  $MOVE_BRANCH
  echo
fi

if [ $STASH ]; then
  echo '$ git stash pop'
  git stash pop -q
  echo
fi

echo "Successfully cherry-picked to $BRANCH."
echo

if [ "$PULL_REQUEST" ]; then
  if [ $MAKE_NEW ]; then # already fetched
    NO_FETCH=-f
  fi
  echo "$ git-pull-request $BRANCH"
  git-pull-request $BRANCH
fi