combine-diff: factor out stat-format mask

There are several conditionals in the combine diff code that check if
we're doing --stat or --numstat output. Since these must all remain in
sync, let's pull them out into a separate bit-mask.

Arguably this could go into diff.h along with the other DIFF_FORMAT
macros, but it's not clear that the definition of "which formats are
stat" is universal (e.g., does --dirstat count? --summary?). So let's
keep this local to combine-diff.c, where the meaning is more clearly
"stat formats that combine-diff supports".

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/combine-diff.c b/combine-diff.c
index ad7752ea6b7e3173066e346b7dd314e7707f7d8c..ebf9064e27be71688cc5d446f29aefabf65b4529 100644 (file)
--- a/combine-diff.c
+++ b/combine-diff.c
@@ -1321,6 +1321,11 @@ static const char *path_path(void *obj)
        return path->path;
 }
 
+/*
+ * Diff stat formats which we always compute solely against the first parent.
+ */
+#define STAT_FORMAT_MASK (DIFF_FORMAT_NUMSTAT \
+                         | DIFF_FORMAT_DIFFSTAT)
 
 /* find set of paths that every parent touches */
 static struct combine_diff_path *find_paths_generic(const struct object_id *oid,
@@ -1342,8 +1347,7 @@ static struct combine_diff_path *find_paths_generic(const struct object_id *oid,
                 * show stat against the first parent even when doing
                 * combined diff.
                 */
-               int stat_opt = (output_format &
-                               (DIFF_FORMAT_NUMSTAT|DIFF_FORMAT_DIFFSTAT));
+               int stat_opt = output_format & STAT_FORMAT_MASK;
                if (i == 0 && stat_opt)
                        opt->output_format = stat_opt;
                else
@@ -1470,8 +1474,7 @@ void diff_tree_combined(const struct object_id *oid,
                 * show stat against the first parent even
                 * when doing combined diff.
                 */
-               stat_opt = (opt->output_format &
-                               (DIFF_FORMAT_NUMSTAT|DIFF_FORMAT_DIFFSTAT));
+               stat_opt = opt->output_format & STAT_FORMAT_MASK;
                if (stat_opt) {
                        diffopts.output_format = stat_opt;
 
@@ -1515,8 +1518,7 @@ void diff_tree_combined(const struct object_id *oid,
                                show_raw_diff(p, num_parent, rev);
                        needsep = 1;
                }
-               else if (opt->output_format &
-                        (DIFF_FORMAT_NUMSTAT|DIFF_FORMAT_DIFFSTAT))
+               else if (opt->output_format & STAT_FORMAT_MASK)
                        needsep = 1;
                else if (opt->output_format & DIFF_FORMAT_CALLBACK)
                        handle_combined_callback(opt, paths, num_parent, num_paths);