Merge branch 'jt/tags-to-promised-blobs-fix'

The lazy clone support had a few places where missing but promised
objects were not correctly tolerated, which have been fixed.

* jt/tags-to-promised-blobs-fix:
  tag: don't warn if target is missing but promised
  revision: tolerate promised targets of tags

revision.c

@@ -251,6 +251,9 @@ static struct commit *handle_commit(struct rev_info *revs,
 		if (!object) {
 			if (revs->ignore_missing_links || (flags & UNINTERESTING))
 				return NULL;
+			if (revs->exclude_promisor_objects &&
+			    is_promisor_object(&tag->tagged->oid))
+				return NULL;
 			die("bad object %s", oid_to_hex(&tag->tagged->oid));
 		}
 		object->flags |= flags;

t/t5616-partial-clone.sh

@@ -216,6 +216,50 @@ test_expect_success 'upon cloning, check that all refs point to objects' '
 	! test -e "$HTTPD_ROOT_PATH/one-time-sed"
 '
 
+test_expect_success 'when partial cloning, tolerate server not sending target of tag' '
+	SERVER="$HTTPD_DOCUMENT_ROOT_PATH/server" &&
+	rm -rf "$SERVER" repo &&
+	test_create_repo "$SERVER" &&
+	test_commit -C "$SERVER" foo &&
+	test_config -C "$SERVER" uploadpack.allowfilter 1 &&
+	test_config -C "$SERVER" uploadpack.allowanysha1inwant 1 &&
+
+	# Create an annotated tag pointing to a blob.
+	BLOB=$(echo blob-contents | git -C "$SERVER" hash-object --stdin -w) &&
+	git -C "$SERVER" tag -m message -a myblob "$BLOB" &&
+
+	# Craft a packfile including the tag, but not the blob it points to.
+	# Also, omit objects referenced from HEAD in order to force a second
+	# fetch (to fetch missing objects) upon the automatic checkout that
+	# happens after a clone.
+	printf "%s\n%s\n--not\n%s\n%s\n" \
+		$(git -C "$SERVER" rev-parse HEAD) \
+		$(git -C "$SERVER" rev-parse myblob) \
+		$(git -C "$SERVER" rev-parse HEAD^{tree}) \
+		$(git -C "$SERVER" rev-parse myblob^{blob}) |
+		git -C "$SERVER" pack-objects --thin --stdout >incomplete.pack &&
+
+	# Replace the existing packfile with the crafted one. The protocol
+	# requires that the packfile be sent in sideband 1, hence the extra
+	# \x01 byte at the beginning.
+	printf "1,/packfile/!c %04x\\\\x01%s0000" \
+		"$(($(wc -c <incomplete.pack) + 5))" \
+		"$(sed_escape <incomplete.pack)" \
+		>"$HTTPD_ROOT_PATH/one-time-sed" &&
+
+	# Use protocol v2 because the sed command looks for the "packfile"
+	# section header.
+	test_config -C "$SERVER" protocol.version 2 &&
+
+	# Exercise to make sure it works.
+	git -c protocol.version=2 clone \
+		--filter=blob:none $HTTPD_URL/one_time_sed/server repo 2> err &&
+	! grep "missing object referenced by" err &&
+
+	# Ensure that the one-time-sed script was used.
+	! test -e "$HTTPD_ROOT_PATH/one-time-sed"
+'
+
 stop_httpd
 
 test_done

tag.c

@@ -6,6 +6,7 @@
 #include "blob.h"
 #include "alloc.h"
 #include "gpg-interface.h"
+#include "packfile.h"
 
 const char *tag_type = "tag";
 
@@ -66,12 +67,18 @@ int gpg_verify_tag(const struct object_id *oid, const char *name_to_report,
 
 struct object *deref_tag(struct repository *r, struct object *o, const char *warn, int warnlen)
 {
+	struct object_id *last_oid = NULL;
 	while (o && o->type == OBJ_TAG)
-		if (((struct tag *)o)->tagged)
+		if (((struct tag *)o)->tagged) {
-			o = parse_object(r, &((struct tag *)o)->tagged->oid);
+			last_oid = &((struct tag *)o)->tagged->oid;
-		else
+			o = parse_object(r, last_oid);
+		} else {
+			last_oid = NULL;
 			o = NULL;
+		}
 	if (!o && warn) {
+		if (last_oid && is_promisor_object(last_oid))
+			return NULL;
 		if (!warnlen)
 			warnlen = strlen(warn);
 		error("missing object referenced by '%.*s'", warnlen, warn);