git-cms-fetch-pr

#! /bin/bash

function usage() {
  cat <<@EOF
Usage: git cms-fetch-pr <pull request> [<local branch>]

Description:
  Fetch a pull request from https://github.com/cms-sw/cmssw.git into the local branch 
  pull/<pull request> , or <local branch> if specified.
@EOF
  exit $1
}

PULL=
BRANCH=

while [ "$#" != 0 ]; do
  case "$1" in
    -*)
      echo Unknown option $1
      usage 1
      ;;
    *)
      if [ "$PULL" == "" ]; then
        PULL=$1
      elif [ "$BRANCH" == "" ]; then
        BRANCH=$1
      else
        echo Unexpected argument $1
        usage 1
      fi
      shift
      ;;
  esac
done

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

if [[ $PULL =~ .*:.* ]]; then
  USER=$(echo "$PULL" | cut -d: -f1)
  PULL=$(echo "$PULL" | cut -d: -f2)
else
  USER="cms-sw"
fi

REMOTE="git@github.com:$USER/cmssw.git"

if [ -z "$BRANCH"]; then
    BRANCH="pull/$PULL"
fi

cd $CMSSW_BASE/src
git fetch -n $REMOTE refs/pull/$PULL/head:$BRANCH