[PATCH 06/17] Let fetch_pack() inform caller about number of unique heads

[mhagger@alum.mit.edu]

From: Michael Haggerty <mhagger@alum.mit.edu>

fetch_pack() remotes duplicates from the list (nr_heads, heads),
thereby shrinking the list.  But previously, the caller was not
informed about the shrinkage.  This would cause a spurious error
message to be emitted by cmd_fetch_pack() if "git fetch-pack" is
called with duplicate refnames.

So change the signature of fetch_pack() to accept nr_heads by
reference, and if any duplicates were removed then modify it to
reflect the number of remaining references.

The last test of t5500 inexplicably *required* "git fetch-pack" to
fail when fetching a list of references that contains duplicates;
i.e., it insisted on the buggy behavior.  So change the test to expect
the correct behavior.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
---
 builtin/fetch-pack.c  | 12 ++++++------
 fetch-pack.h          |  2 +-
 t/t5500-fetch-pack.sh |  2 +-
 transport.c           |  2 +-
 4 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/builtin/fetch-pack.c b/builtin/fetch-pack.c
index a6406e7..3c93ec4 100644
--- a/builtin/fetch-pack.c
+++ b/builtin/fetch-pack.c
@@ -1021,7 +1021,7 @@ int cmd_fetch_pack(int argc, const char **argv, const char *prefix)
 	get_remote_heads(fd[0], &ref, 0, NULL);
 
 	ref = fetch_pack(&args, fd, conn, ref, dest,
-		nr_heads, heads, pack_lockfile_ptr);
+		&nr_heads, heads, pack_lockfile_ptr);
 	if (pack_lockfile) {
 		printf("lock %s\n", pack_lockfile);
 		fflush(stdout);
@@ -1062,7 +1062,7 @@ struct ref *fetch_pack(struct fetch_pack_args *my_args,
 		       int fd[], struct child_process *conn,
 		       const struct ref *ref,
 		       const char *dest,
-		       int nr_heads,
+		       int *nr_heads,
 		       char **heads,
 		       char **pack_lockfile)
 {
@@ -1077,16 +1077,16 @@ struct ref *fetch_pack(struct fetch_pack_args *my_args,
 			st.st_mtime = 0;
 	}
 
-	if (heads && nr_heads) {
-		qsort(heads, nr_heads, sizeof(*heads), compare_heads);
-		nr_heads = remove_duplicates(nr_heads, heads);
+	if (heads && *nr_heads) {
+		qsort(heads, *nr_heads, sizeof(*heads), compare_heads);
+		*nr_heads = remove_duplicates(*nr_heads, heads);
 	}
 
 	if (!ref) {
 		packet_flush(fd[1]);
 		die("no matching remote head");
 	}
-	ref_cpy = do_fetch_pack(fd, ref, nr_heads, heads, pack_lockfile);
+	ref_cpy = do_fetch_pack(fd, ref, *nr_heads, heads, pack_lockfile);
 
 	if (args.depth > 0) {
 		struct cache_time mtime;
diff --git a/fetch-pack.h b/fetch-pack.h
index 1dbe90f..a9d505b 100644
--- a/fetch-pack.h
+++ b/fetch-pack.h
@@ -21,7 +21,7 @@ struct ref *fetch_pack(struct fetch_pack_args *args,
 		       int fd[], struct child_process *conn,
 		       const struct ref *ref,
 		       const char *dest,
-		       int nr_heads,
+		       int *nr_heads,
 		       char **heads,
 		       char **pack_lockfile);
 
diff --git a/t/t5500-fetch-pack.sh b/t/t5500-fetch-pack.sh
index 3cc3346..0d4edcb 100755
--- a/t/t5500-fetch-pack.sh
+++ b/t/t5500-fetch-pack.sh
@@ -391,7 +391,7 @@ test_expect_success 'fetch mixed refs from cmdline and stdin' '
 test_expect_success 'test duplicate refs from stdin' '
 	(
 	cd client &&
-	test_must_fail git fetch-pack --stdin --no-progress .. <../input.dup
+	git fetch-pack --stdin --no-progress .. <../input.dup
 	) >output &&
 	cut -d " " -f 2 <output | sort >actual &&
 	test_cmp expect actual
diff --git a/transport.c b/transport.c
index 1811b50..f7bbf58 100644
--- a/transport.c
+++ b/transport.c
@@ -548,7 +548,7 @@ static int fetch_refs_via_pack(struct transport *transport,
 
 	refs = fetch_pack(&args, data->fd, data->conn,
 			  refs_tmp ? refs_tmp : transport->remote_refs,
-			  dest, nr_heads, heads, &transport->pack_lockfile);
+			  dest, &nr_heads, heads, &transport->pack_lockfile);
 	close(data->fd[0]);
 	close(data->fd[1]);
 	if (finish_connect(data->conn))
-- 
1.7.11.3