mergetool-lib: call vim in readonly mode for diffs

When [g]vimdiff is called for files which are opened already, the editor
complains about the existing swap file. But we do not want to write
anything when called from difftool. So, make difftool use "-R" for the
vim family. This

- prevents the use of a swap file and
- marks the buffers readonly.

Signed-off-by: Michael J Gruber <git@drmicha.warpmail.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/git-mergetool--lib.sh b/git-mergetool--lib.sh
index 77d4aee..78ce49e 100644 (file)
--- a/git-mergetool--lib.sh
+++ b/git-mergetool--lib.sh
@@ -182,7 +182,7 @@ run_merge_tool () {
                        fi
                        check_unchanged
                else
-                       "$merge_tool_path" -f -d -c "wincmd l" \
+                       "$merge_tool_path" -R -f -d -c "wincmd l" \
                                "$LOCAL" "$REMOTE"
                fi
                ;;
@@ -193,7 +193,7 @@ run_merge_tool () {
                                "$LOCAL" "$MERGED" "$REMOTE"
                        check_unchanged
                else
-                       "$merge_tool_path" -f -d -c "wincmd l" \
+                       "$merge_tool_path" -R -f -d -c "wincmd l" \
                                "$LOCAL" "$REMOTE"
                fi
                ;;