Allow a commit message to be specified to merge-to-branch.sh

R=jkummerow@chromium.org

Review URL: https://chromiumcodereview.appspot.com/9844015

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11181 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

tools/common-includes.sh

@@ -77,20 +77,27 @@ delete_branch() {
 persist() {
   local VARNAME=$1
   local FILE="$PERSISTFILE_BASENAME-$VARNAME"
-  echo "${!VARNAME}" > $FILE
+  local VALUE="${!VARNAME}"
+  if [ -z "$VALUE" ] ; then
+    VALUE="__EMPTY__"
+  fi
+  echo "$VALUE" > $FILE
 }
 
 restore() {
   local VARNAME=$1
   local FILE="$PERSISTFILE_BASENAME-$VARNAME"
   local VALUE="$(cat $FILE)"
+  [[ -z "$VALUE" ]] && die "Variable '$VARNAME' could not be restored."
+  if [ "$VALUE" == "__EMPTY__" ] ; then
+    VALUE=""
+  fi
   eval "$VARNAME=\"$VALUE\""
 }
 
 restore_if_unset() {
   local VARNAME=$1
   [[ -z "${!VARNAME}" ]] && restore "$VARNAME"
-  [[ -z "${!VARNAME}" ]] && die "Variable '$VARNAME' could not be restored."
 }
 
 initial_environment_checks() {

tools/merge-to-branch.sh

@@ -49,6 +49,7 @@ OPTIONS:
   -h    Show this message
   -s    Specify the step where to start work. Default: 0.
   -p    Specify a patch file to apply as part of the merge
+  -m    Specify a commit message for the patch
   -r    Reverse specified patches
 EOF
 }
@@ -69,7 +70,7 @@ restore_patch_commit_hashes_if_unset() {
 
 ########## Option parsing
 
-while getopts ":hs:fp:r" OPTION ; do
+while getopts ":hs:fp:rm:" OPTION ; do
   case $OPTION in
     h)  usage
         exit 0
@@ -80,6 +81,8 @@ while getopts ":hs:fp:r" OPTION ; do
         ;;
     r)  REVERSE_PATCH="--reverse"
         ;;
+    m)  NEW_COMMIT_MSG=$OPTARG
+        ;;
     s)  START_STEP=$OPTARG
         ;;
     ?)  echo "Illegal option: -$OPTARG"
@@ -101,8 +104,13 @@ touch "$ALREADY_MERGING_SENTINEL_FILE"
 initial_environment_checks
 
 if [ $START_STEP -le $CURRENT_STEP ] ; then
-  if [ ${#@} -lt 2 ] && [ -z "$EXTRA_PATCH" ] ; then
-    die "Either a patch file or revision numbers must be specified"
+  if [ ${#@} -lt 2 ] ; then
+    if [ -z "$EXTRA_PATCH" ] ; then
+      die "Either a patch file or revision numbers must be specified"
+    fi
+    if [ -z "$NEW_COMMIT_MSG" ] ; then
+      die "You must specify a merge comment if no patches are specified"
+    fi
   fi
   echo ">>> Step $CURRENT_STEP: Preparation"
   MERGE_TO_BRANCH=$1
@@ -134,9 +142,7 @@ revisions associated with the patches."
     REVISION_LIST="$REVISION_LIST r$REVISION"
     let current+=1
   done
-  if [ -z "$REVISION_LIST" ] ; then
-    NEW_COMMIT_MSG="Applied patch to $MERGE_TO_BRANCH branch."
-  else
+  if [ -n "$REVISION_LIST" ] ; then
     if [ -n "$REVERSE_PATCH" ] ; then
       NEW_COMMIT_MSG="Rollback of$REVISION_LIST in $MERGE_TO_BRANCH branch."
     else