git-cms-merge-topic

#!/bin/bash -e

case `uname` in
  Linux) ECHO="echo -e" ;;
  *) ECHO="echo" ;;
esac

usage() {
  $ECHO "git cms-merge-topic [options] <github-user>:<branch>"
  $ECHO "git cms-merge-topic [options] <official-cmssw-branch>"
  $ECHO "git cms-merge-topic [options] <pull-request-id>"
  $ECHO
  $ECHO "Options:"
  $ECHO "-d, --debug        \tenable debug output"
  $ECHO "    --https        \taccess GitHub over https (default)"
  $ECHO "    --ssh          \taccess GitHub over ssh"
  $ECHO "-q, --quiet        \tbe completely quiet"
  $ECHO "--no-commit        \tdo not do the final commit when merging"
  $ECHO "-s, --strategy     \tspecify strategy when merging"
  $ECHO "-X, --strategy-option     \tspecify strategy when merging"
  $ECHO "-u, --unsafe       \tdo not perform checkdeps at the end"
  $ECHO "-v, --verbose      \tshow verbose output"
  exit 1
}

# colors and formatting
RED='\033[31m'
NORMAL='\033[0m'

NORMAL_STREAM=/dev/stdout
VERBOSE_STREAM=/dev/stdout
DEBUG_STREAM=/dev/null
PROTOCOL=https

while [ $# -gt 0 ]; do
  case $1 in 
    -u|--unsafe)
      UNSAFE=true
      shift
      ;;
    -v|--verbose)
      NORMAL_STREAM=/dev/stdout
      VERBOSE_STREAM=/dev/stdout
      DEBUG_STREAM=/dev/null
      shift
      ;;
    -q|--quiet)
      NORMAL_STREAM=/dev/null
      VERBOSE_STREAM=/dev/null
      DEBUG_STREAM=/dev/null
      shift
      ;;
    -d|--debug)
      NORMAL_STREAM=/dev/stdout
      VERBOSE_STREAM=/dev/stdout
      DEBUG_STREAM=/dev/stdout
      DEBUG_OPT=-d
      set -x
      shift
      ;;
    --https )
      PROTOCOL=https
      shift
      ;;
    --ssh )
      PROTOCOL=ssh
      shift
      ;;
    --no-commit )
      NO_COMMIT=--no-commit 
      shift
      ;;
    -s | --strategy )
      MERGE_STRATEGY="-s $2"
      shift; shift
      ;;
    -X | --strategy-option )
      STRATEGY_OPTION="-X $2"
      shift; shift
      ;;
    -*)
      echo "Unknown option $1" ; exit 1 ;;
    *)
      if [ ! X$BRANCH = X ]; then
        echo "Unexpected extra argument $1" ; exit 1
      fi
      # Handle branch options:
      #
      # - Generic personal branch: `<user-name>:<branch-name>`
      # - Generic cms-sw branch: `<branch-name>`
      # - Pull request: `<pull-request-id>`
      GITHUB_USER=cms-sw ; 
      BRANCH=$1 ;
      case $1 in
        *:*)
          BRANCH=`echo $1 | cut -f2 -d:`
          GITHUB_USER=`echo $1 | cut -f1 -d:` ;;
        [0-9]*) 
          BRANCH=refs/pull/$1/head ;; 
      esac ;
      shift
    ;;
  esac
done
if [ X$BRANCH = X ]; then
  usage
fi

PULL_ID=$1

# initialize the local repository
if [ -z "$CMSSW_BASE" ]; then
  echo "CMSSW environment not setup, please run 'cmsenv' before 'git cms-merge-topic'."
  exit 1
fi
if ! [ -d $CMSSW_BASE/src/.git ]; then
  git cms-init $INITOPTIONS
fi

cd $CMSSW_BASE/src
git fetch . +HEAD:merge-attempt || { echo "You are on a failed merge branch. Do \"git branch\" and checkout the one you were on."; exit 1; }

if [ "$(git status --porcelain --untracked=no | grep '^[ACDMRU]')" ]; then
  $ECHO "${RED}Error:${NORMAL} there are staged but not committed changes on your working tree, please commit or stash them."
  exit 1
fi

if [ "$PROTOCOL" = "ssh" ]; then
  REPOSITORY=git@github.com:$GITHUB_USER/cmssw.git
else
  REPOSITORY=https://github.com/$GITHUB_USER/cmssw.git
fi

# check if the "branch" is actually an annotated tag, and dereference it
COMMIT=`git ls-remote -t $REPOSITORY $BRANCH^{} | cut -c -40`
if [ -z "$COMMIT" ]; then
  COMMIT=$BRANCH
fi

# Fetch the branch specified from github and replace merge-attempt with it. 
# The + is used to force the merge-attampt branch to be updated.
git fetch -n $REPOSITORY +$COMMIT:$GITHUB_USER/$BRANCH
# Save the name of the current branch.
CURRENT_BRANCH=`git rev-parse --abbrev-ref HEAD`
# Attempt a merge in a separate branch
git checkout merge-attempt >$DEBUG_STREAM 
MERGE_BASE=`git merge-base $GITHUB_USER/$BRANCH $CURRENT_BRANCH`
git cms-sparse-checkout $DEBUG_OPT $MERGE_BASE $GITHUB_USER/$BRANCH
git read-tree -mu HEAD
git merge $NO_COMMIT $MERGE_STRATEGY $STRATEGY_OPTION --no-ff -m "Merged $BRANCH from repository $GITHUB_USER" $GITHUB_USER/$BRANCH || { echo "Unable to merge branch $BRANCH from repository $GITHUB_USER." ; exit 1; }
if [ ! X$NO_COMMIT = X ]; then
  echo \"--no-commit\" specified: not committing and leaving you on the merge-attempt branch.\n Use git-status to check changes. ; exit 0
fi
git checkout $CURRENT_BRANCH 
# Add the missing files.
git read-tree -mu HEAD
# This should always be a FF commit.
git merge --ff merge-attempt >$DEBUG_STREAM 
# Delete the branch used for merge
git branch -D merge-attempt >$DEBUG_STREAM || true
# Do checkdeps unless not specified.
if [ ! "X$UNSAFE" = Xtrue ]; then
  git cms-checkdeps -a
fi