Merge branch 'th/push-local-ff-check-without-lazy-fetch'

When "git push" notices that the commit at the tip of the ref on
the other side it is about to overwrite does not exist locally, it
used to first try fetching it if the local repository is a partial
clone. The command has been taught not to do so and immediately
fail instead.

* th/push-local-ff-check-without-lazy-fetch:
  push: don't fetch commit object when checking existence

remote.c

@@ -1778,7 +1778,7 @@ void set_ref_status_for_push(struct ref *remote_refs, int send_mirror,
 		if (!reject_reason && !ref->deletion && !is_null_oid(&ref->old_oid)) {
 			if (starts_with(ref->name, "refs/tags/"))
 				reject_reason = REF_STATUS_REJECT_ALREADY_EXISTS;
-			else if (!repo_has_object_file(the_repository, &ref->old_oid))
+			else if (!repo_has_object_file_with_flags(the_repository, &ref->old_oid, OBJECT_INFO_SKIP_FETCH_OBJECT))
 				reject_reason = REF_STATUS_REJECT_FETCH_FIRST;
 			else if (!lookup_commit_reference_gently(the_repository, &ref->old_oid, 1) ||
 				 !lookup_commit_reference_gently(the_repository, &ref->new_oid, 1))

t/t0410-partial-clone.sh

@@ -689,6 +689,25 @@ test_expect_success 'lazy-fetch when accessing object not in the_repository' '
 	! grep "[?]$FILE_HASH" out
 '
 
+test_expect_success 'push should not fetch new commit objects' '
+	rm -rf server client &&
+	test_create_repo server &&
+	test_config -C server uploadpack.allowfilter 1 &&
+	test_config -C server uploadpack.allowanysha1inwant 1 &&
+	test_commit -C server server1 &&
+
+	git clone --filter=blob:none "file://$(pwd)/server" client &&
+	test_commit -C client client1 &&
+
+	test_commit -C server server2 &&
+	COMMIT=$(git -C server rev-parse server2) &&
+
+	test_must_fail git -C client push 2>err &&
+	grep "fetch first" err &&
+	git -C client rev-list --objects --missing=print "$COMMIT" >objects &&
+	grep "^[?]$COMMIT" objects
+'
+
 . "$TEST_DIRECTORY"/lib-httpd.sh
 start_httpd