mergetool: add an option for writing to a temporary directory

Teach mergetool to write files in a temporary directory when
'mergetool.writeToTemp' is true.

This is helpful for tools such as Eclipse which cannot cope with
multiple copies of the same file in the worktree.

Suggested-by: Charles Bailey <charles@hashpling.org>
Signed-off-by: David Aguilar <davvid@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/Documentation/config.txt b/Documentation/config.txt
index c08286e968ad057c288b72f77e877f42a640ae5f..c305aff660ff3e51a969dd90bb030d0fc281f8f4 100644 (file)
--- a/Documentation/config.txt
+++ b/Documentation/config.txt
@@ -1755,6 +1755,12 @@ mergetool.keepTemporaries::
        preserved, otherwise they will be removed after the tool has
        exited. Defaults to `false`.
 
+mergetool.writeToTemp::
+       Git writes temporary 'BASE', 'LOCAL', and 'REMOTE' versions of
+       conflicting files in the worktree by default.  Git will attempt
+       to use a temporary directory for these files when set `true`.
+       Defaults to `false`.
+
 mergetool.prompt::
        Prompt before each invocation of the merge resolution program.
 

diff --git a/git-mergetool.sh b/git-mergetool.sh
index 0ff6566a0eff8819023254d39c26ed45670b9a7b..83863f2288a6a5252e55a6a8d1ffe7876e27bfab 100755 (executable)
--- a/git-mergetool.sh
+++ b/git-mergetool.sh
@@ -37,6 +37,19 @@ base_present () {
        test -n "$base_mode"
 }
 
+mergetool_tmpdir_init () {
+       if test "$(git config --bool mergetool.writeToTemp)" != true
+       then
+               MERGETOOL_TMPDIR=.
+               return 0
+       fi
+       if MERGETOOL_TMPDIR=$(mktemp -d -t "git-mergetool-XXXXXX" 2>/dev/null)
+       then
+               return 0
+       fi
+       die "error: mktemp is needed when 'mergetool.writeToTemp' is true"
+}
+
 cleanup_temp_files () {
        if test "$1" = --save-backup
        then
@@ -46,6 +59,10 @@ cleanup_temp_files () {
        else
                rm -f -- "$LOCAL" "$REMOTE" "$BASE" "$BACKUP"
        fi
+       if test "$MERGETOOL_TMPDIR" != "."
+       then
+               rmdir "$MERGETOOL_TMPDIR"
+       fi
 }
 
 describe_file () {
@@ -235,10 +252,20 @@ merge_file () {
                BASE=$MERGED
                ext=
        fi
-       BACKUP="./${BASE}_BACKUP_$$$ext"
-       LOCAL="./${BASE}_LOCAL_$$$ext"
-       REMOTE="./${BASE}_REMOTE_$$$ext"
-       BASE="./${BASE}_BASE_$$$ext"
+
+       mergetool_tmpdir_init
+
+       if test "$MERGETOOL_TMPDIR" != "."
+       then
+               # If we're using a temporary directory then write to the
+               # top-level of that directory.
+               BASE=${BASE##*/}
+       fi
+
+       BACKUP="$MERGETOOL_TMPDIR/${BASE}_BACKUP_$$$ext"
+       LOCAL="$MERGETOOL_TMPDIR/${BASE}_LOCAL_$$$ext"
+       REMOTE="$MERGETOOL_TMPDIR/${BASE}_REMOTE_$$$ext"
+       BASE="$MERGETOOL_TMPDIR/${BASE}_BASE_$$$ext"
 
        base_mode=$(git ls-files -u -- "$MERGED" | awk '{if ($3==1) print $1;}')
        local_mode=$(git ls-files -u -- "$MERGED" | awk '{if ($3==2) print $1;}')