[PATCH 1/2] filter-branch: provide the convenience functions also for commit filters

[Johannes Schindelin <Johannes.Schindelin@gmx.de>]

By sourcing git-filter-branch and stopping after the function definitions,
the commit filter can now access the convenience functions like "map".

This is done automatically if you specify a commit filter.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 git-filter-branch.sh |   12 ++++++++----
 1 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/git-filter-branch.sh b/git-filter-branch.sh
index 0d000ed..b574612 100755
--- a/git-filter-branch.sh
+++ b/git-filter-branch.sh
@@ -8,9 +8,6 @@
 # a new branch. You can specify a number of filters to modify the commits,
 # files and trees.
 
-USAGE="git-filter-branch [-d TEMPDIR] [FILTERS] DESTBRANCH [REV-RANGE]"
-. git-sh-setup
-
 warn () {
         echo "$*" >&2
 }
@@ -69,6 +66,13 @@ set_ident () {
 	echo "[ -n \"\$GIT_${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 "$0")
+
+USAGE="git-filter-branch [-d TEMPDIR] [FILTERS] DESTBRANCH [REV-RANGE]"
+. git-sh-setup
+
 tempdir=.git-rewrite
 filter_env=
 filter_tree=
@@ -118,7 +122,7 @@ do
 		filter_msg="$OPTARG"
 		;;
 	--commit-filter)
-		filter_commit="$OPTARG"
+		filter_commit="SOURCE_FUNCTIONS=1 . \"$this_script\"; $OPTARG"
 		;;
 	--tag-name-filter)
 		filter_tag_name="$OPTARG"
-- 
1.5.3.rc1.16.g9d6f-dirty