A small shell script for exporting Firefox patches from git repositories to hg ones.

export-patches

#!/bin/bash

BUG=$(git branch | fgrep '*' | awk '{print $2}')
HG_REPO=
BUGZILLA_BUG=
TRY_PUSH=false
COMMIT_INBOUND=false
PRINT_TO_STDOUT=false
DONTBUILD_BECAUSE_NPOTB=false
REVIEWERS=
APPROVERS=
CLOSED_TREE=false

EMAIL_FIXUP="perl -p -e s/gmail.com/mozilla.com/"
PATCH_CONVERT=~/src/patch-converter/git-patch-to-hg-export.py
DEFAULT_TRY_OPTS='-b do -p all -u all -t none -n'

while getopts ":a:b:fh:r:t:cno" opt
do
    case $opt in
	a)
	    APPROVERS=$OPTARG
	    ;;
	b)
            if echo $OPTARG | grep -q ':' 2>/dev/null; then
                BUGZILLA_BUG=($(echo $OPTARG | tr ':' ' '))
            else
	        BUGZILLA_BUG=($OPTARG)
            fi
	    ;;
        f)
            CLOSED_TREE=true
            ;;
	h)
	    if [ ! -d $OPTARG ]; then
		echo "$OPTARG is not a directory"
		exit 1
	    fi
	    HG_REPO=$OPTARG
	    ;;
	r)
	    if echo $OPTARG | grep -q ':' 2>/dev/null; then
		REVIEWERS=($(echo "$OPTARG" | tr ':' ' '))
	    else
		REVIEWERS=("$OPTARG")
	    fi
	    ;;
	t)
	    TRY_OPTS="$OPTARG"
	    TRY_PUSH=true
	    ;;
	c)
	    COMMIT_INBOUND=true
	    ;;
        n)
            DONTBUILD_BECAUSE_NPOTB=true
            ;;
	o)
	    PRINT_TO_STDOUT=true
	    ;;
	?)
	    case $OPTARG in
		t)
		    TRY_OPTS="$DEFAULT_TRY_OPTS"
		    TRY_PUSH=true
		    ;;
		*)
		    echo "no argument provided for $OPTARG"
		    exit 1
		    ;;
	    esac
	    ;;
	*)
	    echo "Invalid option '${opt}'"
	    exit 1
	    ;;
    esac
done

shift $(($OPTIND - 1))

if [ $# -ne 1 ]; then
    echo "need a revision or a revision range"
    exit 1
fi

REVISION_SPEC=$1

if git rev-parse --verify --quiet ${REVISION_SPEC} >/dev/null; then
    REVISION_SPEC="${REVISION_SPEC}^..${REVISION_SPEC}"
fi

if [ -n "${HG_REPO}" -a \! -d "${HG_REPO}/.hg" ]; then
    echo "directory ${HG_REPO} is not a mercurial repository"
    exit 1
fi

if $TRY_PUSH; then
    if [ -z "${HG_REPO}" ]; then
	echo "must specify hg repo for automatic try pushes"
	exit 1
    fi
    if ! (cd ${HG_REPO} && hg paths default|grep -q central 2>/dev/null); then
	echo "must push to try from a mozilla-central repository"
	exit 1
    fi
fi

if $COMMIT_INBOUND; then
    if [ -z "${HG_REPO}" ]; then
	echo "must specify hg repo for automatic inbound pushes"
	exit 1
    fi
    if ! (cd ${HG_REPO} && hg paths default|grep -q inbound 2>/dev/null); then
	echo "must push to inbound from a mozilla-inbound repository"
	exit 1
    fi
    if [ -z "${BUGZILLA_BUG}" ]; then
	echo "must specify bug number for automatic inbound pushes"
	exit 1
    fi
fi

if $COMMIT_INBOUND && $TRY_PUSH; then
    echo "cannot push to inbound and try simultaneously"
    exit 1
fi

if $PRINT_TO_STDOUT; then
    git format-patch -k --stdout ${REVISION_SPEC}
    exit 0
fi

COMMIT_IDS="git log --format=oneline ${REVISION_SPEC}"
N_COMMITS=$(${COMMIT_IDS} | awk '{print $1}' | wc -l)

if [ "${#REVIEWERS[*]}" -ne 1 -a "${#REVIEWERS[*]}" -ne $N_COMMITS ]; then
    echo number of reviewers "${#REVIEWERS[*]}" does not match number of commits $N_COMMITS
    exit 0
fi

if [ "${#BUGZILLA_BUG[*]}" -ne 1 -a "${#BUGZILLA_BUG[*]}" -ne $N_COMMITS ]; then
    echo number of bugs "${#BUGZILLA_BUG[*]}" does not match number of commits $N_COMMITS
    exit 0
fi

LAST_PATCH=

ALL_PATCHES=

i=$((N_COMMITS-1))
for id in $(${COMMIT_IDS} | awk '{print $1}')
do
  logmsg=$(git show --format=oneline $id | head -n 1 | cut -d ' ' -f 2-)
  patch_name=${BUG}-${id}-${i}.patch
  ALL_PATCHES="${ALL_PATCHES} ${patch_name}"
  GIT_EMAIL="git show --unified=3 --binary $id"
  if [ -z "${LAST_PATCH}" ]; then
      LAST_PATCH=${patch_name}
  fi
  FORMAT="format:From %H %cd%nFrom: %aN <%aE>%nDate: %aD%n"
  subject=""
  if git show --format=%s ${id}|head -n 1|egrep -q '^Bug' 2>/dev/null; then
      subject="%s"
  else
      if [ ${#BUGZILLA_BUG[*]} -eq 1 ]; then
          bug="${BUGZILLA_BUG[0]}"
      else
          bug="${BUGZILLA_BUG[${i}]}"
      fi
      subject="Bug ${bug} - %s"
  fi
  if [ -n "${REVIEWERS}" ]; then
      if [ ${#REVIEWERS[*]} -eq 1 ]; then
	  reviewer="${REVIEWERS[0]}"
      else
	  reviewer="${REVIEWERS[${i}]}"
      fi
      subject="${subject}; r=${reviewer}"
  fi
  if [ -n "${APPROVERS}" ]; then
      subject="${subject}; a=${APPROVERS}"
  fi
  FORMAT="${FORMAT}Subject: [PATCH] ${subject}%n%n%b"
  if $DONTBUILD_BECAUSE_NPOTB && [ $i -eq $((N_COMMITS-1)) ]; then
      FORMAT="${FORMAT}%nDONTBUILD because NPOTB"
  fi
  if $CLOSED_TREE && [ $i -eq $((N_COMMITS-1)) ]; then
      FORMAT="${FORMAT}%nLanding this on a CLOSED TREE"
  fi
  if [ -n "${HG_REPO}" ]; then
      # Useless Use of cat (instead of --no-pager) to make output look right
      # in emacs's shell mode.
      git log -n 1 --format="${subject}" $id | cat
      ${GIT_EMAIL} --format="${FORMAT}" |${EMAIL_FIXUP} | ${PATCH_CONVERT} \
	  | $(cd $HG_REPO && hg qimport -f --name ${patch_name} -)
  else
      patch_file=~/src/${patch_name}
      echo "exporting '$FORMAT' to ${patch_file}"
      ${GIT_EMAIL} --format="${FORMAT}"|${EMAIL_FIXUP} | ${PATCH_CONVERT} > ${patch_file}
  fi
  i=$((i-1))
done

if $TRY_PUSH; then
    (cd "$HG_REPO";
     if hg qpush "$LAST_PATCH"; then
         hg qref -m "Bug ${BUG} try: ${TRY_OPTS}";
         hg pushtry
     fi;
     # Whatever happened, we want to pop patches and remove them.
     hg qpop -a && hg qrm $ALL_PATCHES)
fi

if $COMMIT_INBOUND; then
    (cd "$HG_REPO" && hg pull -u;
     if hg qpush "$LAST_PATCH"; then
         hg qfinish -a && hg push inbound
     else
         hg qpop -a && hg qrm $ALL_PATCHES
     fi)
fi