Add unit tests for `SceneMultiplayer`

This PR aims to help "fix" #43440

Also fixing a small typo on `SceneMultiplayer` docs.

1 files changed, 284 insertions, 0 deletions

diff --git a/modules/multiplayer/tests/test_scene_multiplayer.h b/modules/multiplayer/tests/test_scene_multiplayer.h
new file mode 100644
index 0000000000..5e526c9be6
--- /dev/null
+++ b/modules/multiplayer/tests/test_scene_multiplayer.h
@@ -0,0 +1,284 @@
+/**************************************************************************/
+/*  test_scene_multiplayer.h                                              */
+/**************************************************************************/
+/*                         This file is part of:                          */
+/*                             GODOT ENGINE                               */
+/*                        https://godotengine.org                         */
+/**************************************************************************/
+/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
+/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur.                  */
+/*                                                                        */
+/* Permission is hereby granted, free of charge, to any person obtaining  */
+/* a copy of this software and associated documentation files (the        */
+/* "Software"), to deal in the Software without restriction, including    */
+/* without limitation the rights to use, copy, modify, merge, publish,    */
+/* distribute, sublicense, and/or sell copies of the Software, and to     */
+/* permit persons to whom the Software is furnished to do so, subject to  */
+/* the following conditions:                                              */
+/*                                                                        */
+/* The above copyright notice and this permission notice shall be         */
+/* included in all copies or substantial portions of the Software.        */
+/*                                                                        */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,        */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF     */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. */
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY   */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,   */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE      */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                 */
+/**************************************************************************/
+
+#ifndef TEST_SCENE_MULTIPLAYER_H
+#define TEST_SCENE_MULTIPLAYER_H
+
+#include "tests/test_macros.h"
+#include "tests/test_utils.h"
+
+#include "../scene_multiplayer.h"
+
+namespace TestSceneMultiplayer {
+
+static inline Array build_array() {
+	return Array();
+}
+template <typename... Targs>
+static inline Array build_array(Variant item, Targs... Fargs) {
+	Array a = build_array(Fargs...);
+	a.push_front(item);
+	return a;
+}
+
+TEST_CASE("[Multiplayer][SceneMultiplayer] Defaults") {
+	Ref<SceneMultiplayer> scene_multiplayer;
+	scene_multiplayer.instantiate();
+
+	REQUIRE(scene_multiplayer->has_multiplayer_peer());
+	Ref<MultiplayerPeer> multiplayer_peer = scene_multiplayer->get_multiplayer_peer();
+	REQUIRE_MESSAGE(Object::cast_to<OfflineMultiplayerPeer>(multiplayer_peer.ptr()) != nullptr, "By default it must be an OfflineMultiplayerPeer instance.");
+	CHECK_EQ(scene_multiplayer->poll(), Error::OK);
+	CHECK_EQ(scene_multiplayer->get_unique_id(), MultiplayerPeer::TARGET_PEER_SERVER);
+	CHECK_EQ(scene_multiplayer->get_peer_ids(), Vector<int>());
+	CHECK_EQ(scene_multiplayer->get_remote_sender_id(), 0);
+	CHECK_EQ(scene_multiplayer->get_root_path(), NodePath());
+	CHECK(scene_multiplayer->get_connected_peers().is_empty());
+	CHECK_FALSE(scene_multiplayer->is_refusing_new_connections());
+	CHECK_FALSE(scene_multiplayer->is_object_decoding_allowed());
+	CHECK(scene_multiplayer->is_server_relay_enabled());
+	CHECK_EQ(scene_multiplayer->get_max_sync_packet_size(), 1350);
+	CHECK_EQ(scene_multiplayer->get_max_delta_packet_size(), 65535);
+	CHECK(scene_multiplayer->is_server());
+}
+
+TEST_CASE("[Multiplayer][SceneMultiplayer][SceneTree] SceneTree has a OfflineMultiplayerPeer by default") {
+	Ref<SceneMultiplayer> scene_multiplayer = SceneTree::get_singleton()->get_multiplayer();
+	REQUIRE(scene_multiplayer->has_multiplayer_peer());
+
+	Ref<MultiplayerPeer> multiplayer_peer = scene_multiplayer->get_multiplayer_peer();
+	REQUIRE_MESSAGE(Object::cast_to<OfflineMultiplayerPeer>(multiplayer_peer.ptr()) != nullptr, "By default it must be an OfflineMultiplayerPeer instance.");
+}
+
+TEST_CASE("[Multiplayer][SceneMultiplayer][SceneTree] Object configuration add/remove") {
+	Ref<SceneMultiplayer> scene_multiplayer;
+	scene_multiplayer.instantiate();
+
+	SUBCASE("Returns invalid parameter") {
+		CHECK_EQ(scene_multiplayer->object_configuration_add(nullptr, "ImInvalid"), Error::ERR_INVALID_PARAMETER);
+		CHECK_EQ(scene_multiplayer->object_configuration_remove(nullptr, "ImInvalid"), Error::ERR_INVALID_PARAMETER);
+
+		NodePath foo_path("/Foo");
+		NodePath bar_path("/Bar");
+		CHECK_EQ(scene_multiplayer->object_configuration_add(nullptr, foo_path), Error::OK);
+		ERR_PRINT_OFF;
+		CHECK_EQ(scene_multiplayer->object_configuration_remove(nullptr, bar_path), Error::ERR_INVALID_PARAMETER);
+		ERR_PRINT_ON;
+	}
+
+	SUBCASE("Sets root path") {
+		NodePath foo_path("/Foo");
+		CHECK_EQ(scene_multiplayer->object_configuration_add(nullptr, foo_path), Error::OK);
+
+		CHECK_EQ(scene_multiplayer->get_root_path(), foo_path);
+	}
+
+	SUBCASE("Unsets root path") {
+		NodePath foo_path("/Foo");
+		CHECK_EQ(scene_multiplayer->object_configuration_add(nullptr, foo_path), Error::OK);
+
+		CHECK_EQ(scene_multiplayer->object_configuration_remove(nullptr, foo_path), Error::OK);
+		CHECK_EQ(scene_multiplayer->get_root_path(), NodePath());
+	}
+
+	SUBCASE("Add/Remove a MultiplayerSpawner") {
+		Node2D *node = memnew(Node2D);
+		MultiplayerSpawner *spawner = memnew(MultiplayerSpawner);
+
+		CHECK_EQ(scene_multiplayer->object_configuration_add(node, spawner), Error::OK);
+		CHECK_EQ(scene_multiplayer->object_configuration_remove(node, spawner), Error::OK);
+
+		memdelete(spawner);
+		memdelete(node);
+	}
+
+	SUBCASE("Add/Remove a MultiplayerSynchronizer") {
+		Node2D *node = memnew(Node2D);
+		MultiplayerSynchronizer *synchronizer = memnew(MultiplayerSynchronizer);
+
+		CHECK_EQ(scene_multiplayer->object_configuration_add(node, synchronizer), Error::OK);
+		CHECK_EQ(scene_multiplayer->object_configuration_remove(node, synchronizer), Error::OK);
+
+		memdelete(synchronizer);
+		memdelete(node);
+	}
+}
+
+TEST_CASE("[Multiplayer][SceneMultiplayer] Root Path") {
+	Ref<SceneMultiplayer> scene_multiplayer;
+	scene_multiplayer.instantiate();
+
+	SUBCASE("Is set") {
+		NodePath foo_path("/Foo");
+		scene_multiplayer->set_root_path(foo_path);
+
+		CHECK_EQ(scene_multiplayer->get_root_path(), foo_path);
+	}
+
+	SUBCASE("Fails when path is empty") {
+		ERR_PRINT_OFF;
+		scene_multiplayer->set_root_path(NodePath());
+		ERR_PRINT_ON;
+	}
+
+	SUBCASE("Fails when path is relative") {
+		NodePath foo_path("Foo");
+		ERR_PRINT_OFF;
+		scene_multiplayer->set_root_path(foo_path);
+		ERR_PRINT_ON;
+
+		CHECK_EQ(scene_multiplayer->get_root_path(), NodePath());
+	}
+}
+
+// This one could be a dummy callback because the current set of test is not actually testing the full auth flow.
+static Variant auth_callback(Variant sv, Variant pvav) {
+	return Variant();
+}
+
+TEST_CASE("[Multiplayer][SceneMultiplayer][SceneTree] Send Authentication") {
+	Ref<SceneMultiplayer> scene_multiplayer;
+	scene_multiplayer.instantiate();
+	SceneTree::get_singleton()->set_multiplayer(scene_multiplayer);
+	scene_multiplayer->set_auth_callback(callable_mp_static(auth_callback));
+
+	SUBCASE("Is properly sent") {
+		SIGNAL_WATCH(scene_multiplayer.ptr(), "peer_authenticating");
+
+		// Adding a peer to MultiplayerPeer.
+		Ref<MultiplayerPeer> multiplayer_peer = scene_multiplayer->get_multiplayer_peer();
+		int peer_id = 42;
+		multiplayer_peer->emit_signal(SNAME("peer_connected"), peer_id);
+		SIGNAL_CHECK("peer_authenticating", build_array(build_array(peer_id)));
+
+		CHECK_EQ(scene_multiplayer->send_auth(peer_id, String("It's me").to_ascii_buffer()), Error::OK);
+
+		Vector<int> expected_peer_ids = { peer_id };
+		CHECK_EQ(scene_multiplayer->get_authenticating_peer_ids(), expected_peer_ids);
+
+		SIGNAL_UNWATCH(scene_multiplayer.ptr(), "peer_authenticating");
+	}
+
+	SUBCASE("peer_authentication_failed is emitted when a peer is deleted before authentication is completed") {
+		SIGNAL_WATCH(scene_multiplayer.ptr(), "peer_authentication_failed");
+
+		// Adding a peer to MultiplayerPeer.
+		Ref<MultiplayerPeer> multiplayer_peer = scene_multiplayer->get_multiplayer_peer();
+		int peer_id = 42;
+		multiplayer_peer->emit_signal(SNAME("peer_connected"), peer_id);
+		multiplayer_peer->emit_signal(SNAME("peer_disconnected"), peer_id);
+		SIGNAL_CHECK("peer_authentication_failed", build_array(build_array(peer_id)));
+
+		SIGNAL_UNWATCH(scene_multiplayer.ptr(), "peer_authentication_failed");
+	}
+
+	SUBCASE("peer_authentication_failed is emitted when authentication timeout") {
+		SIGNAL_WATCH(scene_multiplayer.ptr(), "peer_authentication_failed");
+		scene_multiplayer->set_auth_timeout(0.01);
+		CHECK_EQ(scene_multiplayer->get_auth_timeout(), 0.01);
+
+		// Adding two peesr to MultiplayerPeer.
+		Ref<MultiplayerPeer> multiplayer_peer = scene_multiplayer->get_multiplayer_peer();
+		int first_peer_id = 42;
+		int second_peer_id = 84;
+		multiplayer_peer->emit_signal(SNAME("peer_connected"), first_peer_id);
+		multiplayer_peer->emit_signal(SNAME("peer_connected"), second_peer_id);
+
+		// Let timeout happens.
+		OS::get_singleton()->delay_usec(500000);
+
+		CHECK_EQ(scene_multiplayer->poll(), Error::OK);
+
+		SIGNAL_CHECK("peer_authentication_failed", build_array(build_array(first_peer_id), build_array(second_peer_id)));
+
+		SIGNAL_UNWATCH(scene_multiplayer.ptr(), "peer_authentication_failed");
+	}
+
+	SUBCASE("Fails when there is no MultiplayerPeer configured") {
+		scene_multiplayer->set_multiplayer_peer(nullptr);
+
+		ERR_PRINT_OFF;
+		CHECK_EQ(scene_multiplayer->send_auth(42, Vector<uint8_t>()), Error::ERR_UNCONFIGURED);
+		ERR_PRINT_ON;
+	}
+
+	SUBCASE("Fails when the peer to send the auth is not pending") {
+		ERR_PRINT_OFF;
+		CHECK_EQ(scene_multiplayer->send_auth(42, String("It's me").to_ascii_buffer()), Error::ERR_INVALID_PARAMETER);
+		ERR_PRINT_ON;
+	}
+}
+
+TEST_CASE("[Multiplayer][SceneMultiplayer][SceneTree] Complete Authentication") {
+	Ref<SceneMultiplayer> scene_multiplayer;
+	scene_multiplayer.instantiate();
+	SceneTree::get_singleton()->set_multiplayer(scene_multiplayer);
+	scene_multiplayer->set_auth_callback(callable_mp_static(auth_callback));
+
+	SUBCASE("Is properly completed") {
+		Ref<MultiplayerPeer> multiplayer_peer = scene_multiplayer->get_multiplayer_peer();
+		int peer_id = 42;
+		multiplayer_peer->emit_signal(SNAME("peer_connected"), peer_id);
+		CHECK_EQ(scene_multiplayer->send_auth(peer_id, String("It's me").to_ascii_buffer()), Error::OK);
+
+		CHECK_EQ(scene_multiplayer->complete_auth(peer_id), Error::OK);
+	}
+
+	SUBCASE("Fails when there is no MultiplayerPeer configured") {
+		scene_multiplayer->set_multiplayer_peer(nullptr);
+
+		ERR_PRINT_OFF;
+		CHECK_EQ(scene_multiplayer->complete_auth(42), Error::ERR_UNCONFIGURED);
+		ERR_PRINT_ON;
+	}
+
+	SUBCASE("Fails when the peer to complete the auth is not pending") {
+		ERR_PRINT_OFF;
+		CHECK_EQ(scene_multiplayer->complete_auth(42), Error::ERR_INVALID_PARAMETER);
+		ERR_PRINT_ON;
+	}
+
+	SUBCASE("Fails to send auth or completed for a second time") {
+		Ref<MultiplayerPeer> multiplayer_peer = scene_multiplayer->get_multiplayer_peer();
+		int peer_id = 42;
+		multiplayer_peer->emit_signal(SNAME("peer_connected"), peer_id);
+		CHECK_EQ(scene_multiplayer->send_auth(peer_id, String("It's me").to_ascii_buffer()), Error::OK);
+		CHECK_EQ(scene_multiplayer->complete_auth(peer_id), Error::OK);
+
+		ERR_PRINT_OFF;
+		CHECK_EQ(scene_multiplayer->send_auth(peer_id, String("It's me").to_ascii_buffer()), Error::ERR_FILE_CANT_WRITE);
+		CHECK_EQ(scene_multiplayer->complete_auth(peer_id), Error::ERR_FILE_CANT_WRITE);
+		ERR_PRINT_ON;
+	}
+}
+
+} // namespace TestSceneMultiplayer
+
+#endif // TEST_SCENE_MULTIPLAYER_H