diff: fix "git show -C -C" output when renaming a binary file

[git.git] / diff.c

diff --git a/diff.c b/diff.c
index a2d8c7f9a7a3bbfca889dedfbda8d6f351fbf016..426fd046652bdfd82ec0ce399446acecb1a5ba49 100644 (file)
--- a/diff.c
+++ b/diff.c
@@ -1596,6 +1596,7 @@ static void builtin_diff(const char *name_a,
                         struct diff_filespec *one,
                         struct diff_filespec *two,
                         const char *xfrm_msg,
+                        int must_show_header,
                         struct diff_options *o,
                         int complete_rewrite)
 {
@@ -1647,16 +1648,19 @@ static void builtin_diff(const char *name_a,
                strbuf_addf(&header, "%snew file mode %06o%s\n", set, two->mode, reset);
                if (xfrm_msg && xfrm_msg[0])
                        strbuf_addf(&header, "%s%s%s\n", set, xfrm_msg, reset);
+               must_show_header = 1;
        }
        else if (lbl[1][0] == '/') {
                strbuf_addf(&header, "%sdeleted file mode %06o%s\n", set, one->mode, reset);
                if (xfrm_msg && xfrm_msg[0])
                        strbuf_addf(&header, "%s%s%s\n", set, xfrm_msg, reset);
+               must_show_header = 1;
        }
        else {
                if (one->mode != two->mode) {
                        strbuf_addf(&header, "%sold mode %06o%s\n", set, one->mode, reset);
                        strbuf_addf(&header, "%snew mode %06o%s\n", set, two->mode, reset);
+                       must_show_header = 1;
                }
                if (xfrm_msg && xfrm_msg[0])
                        strbuf_addf(&header, "%s%s%s\n", set, xfrm_msg, reset);
@@ -1687,8 +1691,11 @@ static void builtin_diff(const char *name_a,
              (diff_filespec_is_binary(two) && !textconv_two) )) {
                /* Quite common confusing case */
                if (mf1.size == mf2.size &&
-                   !memcmp(mf1.ptr, mf2.ptr, mf1.size))
+                   !memcmp(mf1.ptr, mf2.ptr, mf1.size)) {
+                       if (must_show_header)
+                               fprintf(o->file, "%s", header.buf);
                        goto free_ab_and_return;
+               }
                fprintf(o->file, "%s", header.buf);
                strbuf_reset(&header);
                if (DIFF_OPT_TST(o, BINARY))
@@ -1706,7 +1713,7 @@ static void builtin_diff(const char *name_a,
                struct emit_callback ecbdata;
                const struct userdiff_funcname *pe;
 
-               if (!DIFF_XDL_TST(o, WHITESPACE_FLAGS)) {
+               if (!DIFF_XDL_TST(o, WHITESPACE_FLAGS) || must_show_header) {
                        fprintf(o->file, "%s", header.buf);
                        strbuf_reset(&header);
                }
@@ -2315,8 +2322,10 @@ static void fill_metainfo(struct strbuf *msg,
                          struct diff_filespec *one,
                          struct diff_filespec *two,
                          struct diff_options *o,
-                         struct diff_filepair *p)
+                         struct diff_filepair *p,
+                         int *must_show_header)
 {
+       *must_show_header = 1;
        strbuf_init(msg, PATH_MAX * 2 + 300);
        switch (p->status) {
        case DIFF_STATUS_COPIED:
@@ -2344,7 +2353,7 @@ static void fill_metainfo(struct strbuf *msg,
                /* fallthru */
        default:
                /* nothing */
-               ;
+               *must_show_header = 0;
        }
        if (one && two && hashcmp(one->sha1, two->sha1)) {
                int abbrev = DIFF_OPT_TST(o, FULL_INDEX) ? 40 : DEFAULT_ABBREV;
@@ -2378,9 +2387,10 @@ static void run_diff_cmd(const char *pgm,
 {
        const char *xfrm_msg = NULL;
        int complete_rewrite = (p->status == DIFF_STATUS_MODIFIED) && p->score;
+       int must_show_header = 0;
 
        if (msg) {
-               fill_metainfo(msg, name, other, one, two, o, p);
+               fill_metainfo(msg, name, other, one, two, o, p, &must_show_header);
                xfrm_msg = msg->len ? msg->buf : NULL;
        }
 
@@ -2399,7 +2409,8 @@ static void run_diff_cmd(const char *pgm,
        }
        if (one && two)
                builtin_diff(name, other ? other : name,
-                            one, two, xfrm_msg, o, complete_rewrite);
+                            one, two, xfrm_msg, must_show_header,
+                            o, complete_rewrite);
        else
                fprintf(o->file, "* Unmerged path %s\n", name);
 }