format-patch: pick up branch description when no ref is specified

We only try to get branch name in "format-patch origin" case or
similar and not "format-patch -22" where HEAD is automatically
added. Without correct branch name, branch description cannot be
added. Make sure we always get branch name.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin/log.c b/builtin/log.c
index a293a3f05c16064bcafc1db430790ce3af7eefc7..8f488853e18aceb56c00ebacd1da578365a4ea64 100644 (file)
--- a/builtin/log.c
+++ b/builtin/log.c
@@ -1014,6 +1014,7 @@ static char *find_branch_name(struct rev_info *rev)
 {
        int i, positive = -1;
        unsigned char branch_sha1[20];
+       const unsigned char *tip_sha1;
        const char *ref;
        char *full_ref, *branch = NULL;
 
@@ -1025,12 +1026,24 @@ static char *find_branch_name(struct rev_info *rev)
                else
                        return NULL;
        }
-       if (positive < 0)
+       if (0 <= positive) {
+               ref = rev->cmdline.rev[positive].name;
+               tip_sha1 = rev->cmdline.rev[positive].item->sha1;
+       } else if (!rev->cmdline.nr && rev->pending.nr == 1 &&
+                  !strcmp(rev->pending.objects[0].name, "HEAD")) {
+               /*
+                * No actual ref from command line, but "HEAD" from
+                * rev->def was added in setup_revisions()
+                * e.g. format-patch --cover-letter -12
+                */
+               ref = "HEAD";
+               tip_sha1 = rev->pending.objects[0].item->sha1;
+       } else {
                return NULL;
-       ref = rev->cmdline.rev[positive].name;
+       }
        if (dwim_ref(ref, strlen(ref), branch_sha1, &full_ref) &&
            !prefixcmp(full_ref, "refs/heads/") &&
-           !hashcmp(rev->cmdline.rev[positive].item->sha1, branch_sha1))
+           !hashcmp(tip_sha1, branch_sha1))
                branch = xstrdup(full_ref + strlen("refs/heads/"));
        free(full_ref);
        return branch;

diff --git a/t/t4014-format-patch.sh b/t/t4014-format-patch.sh
index 7b536e0fd9e44ef4394a7050f03c55a1c62f6093..8197c74fe5bf6b30392d66dbde352f292bd23bdf 100755 (executable)
--- a/t/t4014-format-patch.sh
+++ b/t/t4014-format-patch.sh
@@ -926,4 +926,11 @@ test_expect_success 'cover letter using branch description (5)' '
        grep hello actual >/dev/null
 '
 
+test_expect_success 'cover letter using branch description (6)' '
+       git checkout rebuild-1 &&
+       test_config branch.rebuild-1.description hello &&
+       git format-patch --stdout --cover-letter -2 >actual &&
+       grep hello actual >/dev/null
+'
+
 test_done