diff: teach diff to display submodule difference with an inline diff

diff --git a/diff.c b/diff.c
index a74e6e06dfb6dba3af802a1c747e23d2b7e0f8fd..b002fdfb81800339f2e9982e291ae2184bd0f670 100644 (file)
--- a/diff.c
+++ b/diff.c
@@ -135,6 +135,8 @@ static int parse_submodule_params(struct diff_options *options, const char *valu
                options->submodule_format = DIFF_SUBMODULE_LOG;
        else if (!strcmp(value, "short"))
                options->submodule_format = DIFF_SUBMODULE_SHORT;
+       else if (!strcmp(value, "diff"))
+               options->submodule_format = DIFF_SUBMODULE_INLINE_DIFF;
        else
                return -1;
        return 0;
@@ -2300,6 +2302,15 @@ static void builtin_diff(const char *name_a,
        struct strbuf header = STRBUF_INIT;
        const char *line_prefix = diff_line_prefix(o);
 
+       diff_set_mnemonic_prefix(o, "a/", "b/");
+       if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
+               a_prefix = o->b_prefix;
+               b_prefix = o->a_prefix;
+       } else {
+               a_prefix = o->a_prefix;
+               b_prefix = o->b_prefix;
+       }
+
        if (o->submodule_format == DIFF_SUBMODULE_LOG &&
            (!one->mode || S_ISGITLINK(one->mode)) &&
            (!two->mode || S_ISGITLINK(two->mode))) {
@@ -2311,6 +2322,17 @@ static void builtin_diff(const char *name_a,
                                two->dirty_submodule,
                                meta, del, add, reset);
                return;
+       } else if (o->submodule_format == DIFF_SUBMODULE_INLINE_DIFF &&
+                  (!one->mode || S_ISGITLINK(one->mode)) &&
+                  (!two->mode || S_ISGITLINK(two->mode))) {
+               const char *del = diff_get_color_opt(o, DIFF_FILE_OLD);
+               const char *add = diff_get_color_opt(o, DIFF_FILE_NEW);
+               show_submodule_inline_diff(o->file, one->path ? one->path : two->path,
+                               line_prefix,
+                               &one->oid, &two->oid,
+                               two->dirty_submodule,
+                               meta, del, add, reset, o);
+               return;
        }
 
        if (DIFF_OPT_TST(o, ALLOW_TEXTCONV)) {
@@ -2318,15 +2340,6 @@ static void builtin_diff(const char *name_a,
                textconv_two = get_textconv(two);
        }
 
-       diff_set_mnemonic_prefix(o, "a/", "b/");
-       if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
-               a_prefix = o->b_prefix;
-               b_prefix = o->a_prefix;
-       } else {
-               a_prefix = o->a_prefix;
-               b_prefix = o->b_prefix;
-       }
-
        /* Never use a non-valid filename anywhere if at all possible */
        name_a = DIFF_FILE_VALID(one) ? name_a : name_b;
        name_b = DIFF_FILE_VALID(two) ? name_b : name_a;