filter-branch: provide the convenience functions also for commit filters

Move the convenience functions to the top of git-filter-branch.sh, and
return from the script when the environment variable SOURCE_FUNCTIONS is
set.

By sourcing git-filter-branch with that variable set automatically, all
commit filters may access the convenience functions like "map".

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 15 insertions, 10 deletions

diff --git a/git-filter-branch.sh b/git-filter-branch.sh
index c166c978e..3b041d81e 100755
--- a/git-filter-branch.sh
+++ b/git-filter-branch.sh
@@ -8,15 +8,6 @@
 # a new branch. You can specify a number of filters to modify the commits,
 # files and trees.
 
-USAGE="[--env-filter <command>] [--tree-filter <command>] \
-[--index-filter <command>] [--parent-filter <command>] \
-[--msg-filter <command>] [--commit-filter <command>] \
-[--tag-name-filter <command>] [--subdirectory-filter <directory>] \
-[--original <namespace>] [-d <directory>] [-f | --force] \
-[<rev-list options>...]"
-
-. git-sh-setup
-
 warn () {
         echo "$*" >&2
 }
@@ -75,6 +66,20 @@ set_ident () {
 	echo "[ -n \"\$GIT_${uid}_NAME\" ] || export GIT_${uid}_NAME=\"\${GIT_${uid}_EMAIL%%@*}\""
 }
 
+# This script can be sourced by the commit filter to get the functions
+test "a$SOURCE_FUNCTIONS" = a1 && return
+this_script="$(cd "$(dirname "$0")"; pwd)"/$(basename "$0")
+export this_script
+
+USAGE="[--env-filter <command>] [--tree-filter <command>] \
+[--index-filter <command>] [--parent-filter <command>] \
+[--msg-filter <command>] [--commit-filter <command>] \
+[--tag-name-filter <command>] [--subdirectory-filter <directory>] \
+[--original <namespace>] [-d <directory>] [-f | --force] \
+[<rev-list options>...]"
+
+. git-sh-setup
+
 tempdir=.git-rewrite
 filter_env=
 filter_tree=
@@ -131,7 +136,7 @@ do
 		filter_msg="$OPTARG"
 		;;
 	--commit-filter)
-		filter_commit="$OPTARG"
+		filter_commit='SOURCE_FUNCTIONS=1 . "$this_script";'" $OPTARG"
 		;;
 	--tag-name-filter)
 		filter_tag_name="$OPTARG"