send-pack: pass remote name for push negotiation

When push.negotiate is enabled, send-pack spawns a 'git fetch
--negotiate-only' subprocess to discover common commits. Previously this
subprocess received only the remote URL, which meant it could not find
per-remote config like remote.<name>.haveRefs.

Add a remote_name field to send_pack_args, set it from the transport
layer where the remote struct is available, and pass the remote name
(falling back to the URL) to the negotiation subprocess. This allows the
subprocess to resolve remote.<name>.haveRefs for the correct remote.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: derrickstolee

send-pack.c

@@ -433,6 +433,7 @@ static void reject_invalid_nonce(const char *nonce, int len)
 
 static void get_commons_through_negotiation(struct repository *r,
 					    const char *url,
+					    const char *remote_name,
 					    const struct ref *remote_refs,
 					    struct oid_array *commons)
 {
@@ -452,7 +453,12 @@ static void get_commons_through_negotiation(struct repository *r,
 			nr_negotiation_tip++;
 		}
 	}
-	strvec_push(&child.args, url);
+	/*
+	 * Use the remote name so the subprocess can find
+	 * remote.<name>.haveRefs config. Fall back to the URL if no
+	 * remote name is available.
+	 */
+	strvec_push(&child.args, remote_name ? remote_name : url);
 
 	if (!nr_negotiation_tip) {
 		child_process_clear(&child);
@@ -528,7 +534,8 @@ int send_pack(struct repository *r,
 	repo_config_get_bool(r, "push.negotiate", &push_negotiate);
 	if (push_negotiate) {
 		trace2_region_enter("send_pack", "push_negotiate", r);
-		get_commons_through_negotiation(r, args->url, remote_refs, &commons);
+		get_commons_through_negotiation(r, args->url, args->remote_name,
+					       remote_refs, &commons);
 		trace2_region_leave("send_pack", "push_negotiate", r);
 	}
 

send-pack.h

@@ -18,6 +18,7 @@ struct repository;
 
 struct send_pack_args {
 	const char *url;
+	const char *remote_name;
 	unsigned verbose:1,
 		quiet:1,
 		porcelain:1,

t/t5516-fetch-push.sh

@@ -254,6 +254,21 @@ test_expect_success 'push with negotiation does not attempt to fetch submodules'
 	! grep "Fetching submodule" err
 '
 
+test_expect_success 'push with negotiation and remote.<name>.haveRefs' '
+	test_when_finished rm -rf haverefs &&
+	mk_empty haverefs &&
+	git push haverefs $the_first_commit:refs/remotes/origin/first_commit &&
+	test_commit -C haverefs unrelated_commit &&
+	git -C haverefs config receive.hideRefs refs/remotes/origin/first_commit &&
+	test_when_finished "rm event" &&
+	GIT_TRACE2_EVENT="$(pwd)/event" \
+		git -c protocol.version=2 -c push.negotiate=1 \
+		-c remote.haverefs.haveRefs=refs/heads/main \
+		push haverefs refs/heads/main:refs/remotes/origin/main &&
+	test_grep \"key\":\"total_rounds\" event &&
+	grep_wrote 2 event # 1 commit, 1 tree
+'
+
 test_expect_success 'push without wildcard' '
 	mk_empty testrepo &&
 

transport.c

@@ -921,6 +921,7 @@ static int git_transport_push(struct transport *transport, struct ref *remote_re
 	args.atomic = !!(flags & TRANSPORT_PUSH_ATOMIC);
 	args.push_options = transport->push_options;
 	args.url = transport->url;
+	args.remote_name = transport->remote->name;
 
 	if (flags & TRANSPORT_PUSH_CERT_ALWAYS)
 		args.push_cert = SEND_PACK_PUSH_CERT_ALWAYS;