describe: Break annotated tag ties by tagger date
If more than one annotated tag points at the same commit, use the
tag whose tagger field has a more recent date stamp. This resolves
non-deterministic cases where the maintainer has done:
$ git tag -a -m "2.1-rc1" v2.1-rc1 deadbeef
$ git tag -a -m "2.1" v2.1 deadbeef
If the tag is an older-style annotated tag with no tagger date, we
assume a date stamp at the UNIX epoch. This will cause us to prefer
an annotated tag that has a valid date.
We could also try to consider the tag object chain, favoring a tag
that "includes" another one:
$ git tag -a -m "2.1-rc0" v2.1-rc1 deadbeef
$ git tag -a -m "2.1" v2.1 v2.1-rc1
However traversing the tag's object chain looking for inclusion
is much more complicated. Its already very likely that even in
these cases the v2.1 tag will have a more recent tagger date than
v2.1-rc1, so with this change describe should still resolve this
by selecting the more recent v2.1.
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/builtin-describe.c b/builtin-describe.c
index 71be2a9..43caff2 100644
--- a/builtin-describe.c
+++ b/builtin-describe.c
@@ -35,7 +35,8 @@
struct commit_name {
struct tag *tag;
- int prio; /* annotated tag = 2, tag = 1, head = 0 */
+ unsigned prio:2; /* annotated tag = 2, tag = 1, head = 0 */
+ unsigned name_checked:1;
unsigned char sha1[20];
char path[FLEX_ARRAY]; /* more */
};
@@ -43,18 +44,53 @@
"head", "lightweight", "annotated",
};
+static int replace_name(struct commit_name *e,
+ int prio,
+ const unsigned char *sha1,
+ struct tag **tag)
+{
+ if (!e || e->prio < prio)
+ return 1;
+
+ if (e->prio == 2 && prio == 2) {
+ /* Multiple annotated tags point to the same commit.
+ * Select one to keep based upon their tagger date.
+ */
+ struct tag *t;
+
+ if (!e->tag) {
+ t = lookup_tag(e->sha1);
+ if (!t || parse_tag(t))
+ return 1;
+ e->tag = t;
+ }
+
+ t = lookup_tag(sha1);
+ if (!t || parse_tag(t))
+ return 0;
+ *tag = t;
+
+ if (e->tag->date < t->date)
+ return 1;
+ }
+
+ return 0;
+}
+
static void add_to_known_names(const char *path,
struct commit *commit,
int prio,
const unsigned char *sha1)
{
struct commit_name *e = commit->util;
- if (!e || e->prio < prio) {
+ struct tag *tag = NULL;
+ if (replace_name(e, prio, sha1, &tag)) {
size_t len = strlen(path)+1;
free(e);
e = xmalloc(sizeof(struct commit_name) + len);
- e->tag = NULL;
+ e->tag = tag;
e->prio = prio;
+ e->name_checked = 0;
hashcpy(e->sha1, sha1);
memcpy(e->path, path, len);
commit->util = e;
@@ -165,10 +201,15 @@
{
if (n->prio == 2 && !n->tag) {
n->tag = lookup_tag(n->sha1);
- if (!n->tag || parse_tag(n->tag) || !n->tag->tag)
+ if (!n->tag || parse_tag(n->tag))
die("annotated tag %s not available", n->path);
+ }
+ if (n->tag && !n->name_checked) {
+ if (!n->tag->tag)
+ die("annotated tag %s has no embedded name", n->path);
if (strcmp(n->tag->tag, all ? n->path + 5 : n->path))
warning("tag '%s' is really '%s' here", n->tag->tag, n->path);
+ n->name_checked = 1;
}
if (n->tag)
