[PATCH] mergetool-lib: add new merge tool TortoiseMerge

[Markus Heidelberg <markus.heidelberg@web.de>]

TortoiseMerge comes with TortoiseSVN or TortoiseGit for Windows. It can
only be used as a merge tool with an existing base file. It cannot be
used without a base nor as a diff tool.

The documentation only mentions the slash '/' as command line option
prefix, which refused to work, but the parser also accepts the dash '-'

See http://code.google.com/p/msysgit/issues/detail?id=226

Signed-off-by: Markus Heidelberg <markus.heidelberg@web.de>
---

This patch goes on top of the current difftool/mergetool patches from David.
This is 'da/difftool' in the current 'pu' and in addition:
[PATCH] mergetool-lib: refactor run_mergetool and check_unchanged
[PATCH] mergetool-lib: specialize opendiff options when in diff mode

I couldn't recognize a special order so I put tortoisemerge at the end
of the list.

 git-mergetool--lib.sh |   15 ++++++++++++++-
 1 files changed, 14 insertions(+), 1 deletions(-)

diff --git a/git-mergetool--lib.sh b/git-mergetool--lib.sh
index 6f0e8f7..4ad2cb5 100644
--- a/git-mergetool--lib.sh
+++ b/git-mergetool--lib.sh
@@ -51,10 +51,13 @@ check_unchanged () {
 
 valid_tool () {
 	case "$1" in
-	kdiff3 | kompare | tkdiff | xxdiff | meld | opendiff | emerge | vimdiff | gvimdiff | ecmerge | diffuse)
+	kdiff3 | kompare | tkdiff | xxdiff | meld | opendiff | emerge | vimdiff | gvimdiff | ecmerge | diffuse | tortoisemerge)
 		if test "$1" = "kompare" && ! diff_mode; then
 			return 1
 		fi
+		if test "$1" = "tortoisemerge" && ! merge_mode; then
+			return 1
+		fi
 		;; # happy
 	*)
 		if test -z "$(get_custom_cmd "$1")"; then
@@ -225,6 +228,16 @@ run_mergetool () {
 		fi
 		status=$?
 		;;
+	tortoisemerge)
+		if $base_present; then
+			touch "$BACKUP"
+			"$merge_tool_path" -base:"$BASE" -mine:"$LOCAL" -theirs:"$REMOTE" -merged:"$MERGED"
+			check_unchanged
+		else
+			echo "TortoiseMerge cannot be used without a base" 1>&2
+			status=1
+		fi
+		;;
 	*)
 		if test -n "$merge_tool_cmd"; then
 			if merge_mode &&
-- 
1.6.2.2.428.gea44ab