difftool: remove the backup file feature

Most users find the backup file feature annoying and there's no
need for it since diff is supposed to be a read-only operation.

Signed-off-by: David Aguilar <davvid@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/contrib/difftool/git-difftool-helper b/contrib/difftool/git-difftool-helper
index ef684b6f68e8376fb20761b8936bef6d9dbee2e3..e74a2747b64fdedb36ae14cdf2fa4285a2237388 100755 (executable)
--- a/contrib/difftool/git-difftool-helper
+++ b/contrib/difftool/git-difftool-helper
@@ -9,31 +9,7 @@
 
 # Set GIT_DIFFTOOL_NO_PROMPT to bypass the per-file prompt.
 should_prompt () {
-       ! test -n "$GIT_DIFFTOOL_NO_PROMPT"
-}
-
-# Should we keep the backup .orig file?
-keep_backup_mode="$(git config --bool merge.keepBackup || echo true)"
-keep_backup () {
-       test "$keep_backup_mode" = "true"
-}
-
-# This function manages the backup .orig file.
-# A backup $MERGED.orig file is created if changes are detected.
-cleanup_temp_files () {
-       if test -n "$MERGED"; then
-               if keep_backup && test "$MERGED" -nt "$BACKUP"; then
-                       test -f "$BACKUP" && mv -- "$BACKUP" "$MERGED.orig"
-               else
-                       rm -f -- "$BACKUP"
-               fi
-       fi
-}
-
-# This is called when users Ctrl-C out of git-difftool-helper
-sigint_handler () {
-       cleanup_temp_files
-       exit 1
+       test -z "$GIT_DIFFTOOL_NO_PROMPT"
 }
 
 # This function prepares temporary files and launches the appropriate
@@ -47,12 +23,6 @@ launch_merge_tool () {
        LOCAL="$2"
        REMOTE="$3"
        BASE="$1"
-       ext="$$$(expr "$MERGED" : '.*\(\.[^/]*\)$')"
-       BACKUP="$MERGED.BACKUP.$ext"
-
-       # Create and ensure that we clean up $BACKUP
-       test -f "$MERGED" && cp -- "$MERGED" "$BACKUP"
-       trap sigint_handler INT
 
        # $LOCAL and $REMOTE are temporary files so prompt
        # the user with the real $MERGED name before launching $merge_tool.
@@ -120,8 +90,6 @@ launch_merge_tool () {
                fi
                ;;
        esac
-
-       cleanup_temp_files
 }
 
 # Verifies that (difftool|mergetool).<tool>.cmd exists