16 files changed, 112 insertions, 47 deletions

diff --git a/core/config/project_settings.cpp b/core/config/project_settings.cpp
index f5baf1a27e..ce7fa1074b 100644
--- a/core/config/project_settings.cpp
+++ b/core/config/project_settings.cpp
@@ -38,6 +38,8 @@
 #include "core/io/file_access.h"
 #include "core/io/file_access_pack.h"
 #include "core/io/marshalls.h"
+#include "core/io/resource_uid.h"
+#include "core/object/script_language.h"
 #include "core/os/keyboard.h"
 #include "core/templates/rb_set.h"
 #include "core/variant/typed_array.h"
@@ -478,6 +480,14 @@ bool ProjectSettings::_load_resource_pack(const String &p_pack, bool p_replace_f
 		return false;
 	}
 
+	if (project_loaded) {
+		// This pack may have declared new global classes (make sure they are picked up).
+		refresh_global_class_list();
+
+		// This pack may have defined new UIDs, make sure they are cached.
+		ResourceUID::get_singleton()->load_from_cache(false);
+	}
+
 	//if data.pck is found, all directory access will be from here
 	DirAccess::make_default<DirAccessPack>(DirAccess::ACCESS_RESOURCES);
 	using_datapack = true;
@@ -1189,6 +1199,19 @@ Variant ProjectSettings::get_setting(const String &p_setting, const Variant &p_d
 	}
 }
 
+void ProjectSettings::refresh_global_class_list() {
+	// This is called after mounting a new PCK file to pick up class changes.
+	is_global_class_list_loaded = false; // Make sure we read from the freshly mounted PCK.
+	Array script_classes = get_global_class_list();
+	for (int i = 0; i < script_classes.size(); i++) {
+		Dictionary c = script_classes[i];
+		if (!c.has("class") || !c.has("language") || !c.has("path") || !c.has("base")) {
+			continue;
+		}
+		ScriptServer::add_global_class(c["class"], c["base"], c["language"], c["path"]);
+	}
+}
+
 TypedArray<Dictionary> ProjectSettings::get_global_class_list() {
 	if (is_global_class_list_loaded) {
 		return global_class_list;
diff --git a/core/config/project_settings.h b/core/config/project_settings.h
index 252b10bd3a..1bad76acb1 100644
--- a/core/config/project_settings.h
+++ b/core/config/project_settings.h
@@ -154,6 +154,7 @@ public:
 	void set_setting(const String &p_setting, const Variant &p_value);
 	Variant get_setting(const String &p_setting, const Variant &p_default_value = Variant()) const;
 	TypedArray<Dictionary> get_global_class_list();
+	void refresh_global_class_list();
 	void store_global_class_list(const Array &p_classes);
 	String get_global_class_list_path() const;
 
diff --git a/core/io/resource_uid.cpp b/core/io/resource_uid.cpp
index edff3e1f14..c14121a53b 100644
--- a/core/io/resource_uid.cpp
+++ b/core/io/resource_uid.cpp
@@ -169,14 +169,16 @@ Error ResourceUID::save_to_cache() {
 	return OK;
 }
 
-Error ResourceUID::load_from_cache() {
+Error ResourceUID::load_from_cache(bool p_reset) {
 	Ref<FileAccess> f = FileAccess::open(get_cache_file(), FileAccess::READ);
 	if (f.is_null()) {
 		return ERR_CANT_OPEN;
 	}
 
 	MutexLock l(mutex);
-	unique_ids.clear();
+	if (p_reset) {
+		unique_ids.clear();
+	}
 
 	uint32_t entry_count = f->get_32();
 	for (uint32_t i = 0; i < entry_count; i++) {
diff --git a/core/io/resource_uid.h b/core/io/resource_uid.h
index 22561c5c03..e56b89f603 100644
--- a/core/io/resource_uid.h
+++ b/core/io/resource_uid.h
@@ -73,7 +73,7 @@ public:
 	String get_id_path(ID p_id) const;
 	void remove_id(ID p_id);
 
-	Error load_from_cache();
+	Error load_from_cache(bool p_reset);
 	Error save_to_cache();
 	Error update_cache();
 
diff --git a/core/object/script_language.cpp b/core/object/script_language.cpp
index d358a8d2a0..5885cf515f 100644
--- a/core/object/script_language.cpp
+++ b/core/object/script_language.cpp
@@ -325,12 +325,24 @@ void ScriptServer::global_classes_clear() {
 
 void ScriptServer::add_global_class(const StringName &p_class, const StringName &p_base, const StringName &p_language, const String &p_path) {
 	ERR_FAIL_COND_MSG(p_class == p_base || (global_classes.has(p_base) && get_global_class_native_base(p_base) == p_class), "Cyclic inheritance in script class.");
-	GlobalScriptClass g;
-	g.language = p_language;
-	g.path = p_path;
-	g.base = p_base;
-	global_classes[p_class] = g;
-	inheriters_cache_dirty = true;
+	GlobalScriptClass *existing = global_classes.getptr(p_class);
+	if (existing) {
+		// Update an existing class (only set dirty if something changed).
+		if (existing->base != p_base || existing->path != p_path || existing->language != p_language) {
+			existing->base = p_base;
+			existing->path = p_path;
+			existing->language = p_language;
+			inheriters_cache_dirty = true;
+		}
+	} else {
+		// Add new class.
+		GlobalScriptClass g;
+		g.language = p_language;
+		g.path = p_path;
+		g.base = p_base;
+		global_classes[p_class] = g;
+		inheriters_cache_dirty = true;
+	}
 }
 
 void ScriptServer::remove_global_class(const StringName &p_class) {
diff --git a/editor/debugger/editor_file_server.cpp b/editor/debugger/editor_file_server.cpp
index e84eb14636..428b5f4c26 100644
--- a/editor/debugger/editor_file_server.cpp
+++ b/editor/debugger/editor_file_server.cpp
@@ -201,7 +201,7 @@ void EditorFileServer::poll() {
 	// Scan files to send.
 	_scan_files_changed(EditorFileSystem::get_singleton()->get_filesystem(), tags, files_to_send, cached_files);
 	// Add forced export files
-	Vector<String> forced_export = EditorExportPlatform::get_forced_export_files();
+	Vector<String> forced_export = EditorExportPlatform::get_main_pack_forced_export_files();
 	for (int i = 0; i < forced_export.size(); i++) {
 		_add_custom_file(forced_export[i], files_to_send, cached_files);
 	}
diff --git a/editor/editor_node.cpp b/editor/editor_node.cpp
index 041784d7da..5183bc4af3 100644
--- a/editor/editor_node.cpp
+++ b/editor/editor_node.cpp
@@ -969,6 +969,9 @@ void EditorNode::_fs_changed() {
 						err = platform->export_zip(export_preset, export_defer.debug, export_path);
 					} else if (export_path.ends_with(".pck")) {
 						err = platform->export_pack(export_preset, export_defer.debug, export_path);
+					} else {
+						ERR_PRINT(vformat("Export path \"%s\" doesn't end with a supported extension.", export_path));
+						err = FAILED;
 					}
 				} else { // Normal project export.
 					String config_error;
diff --git a/editor/export/editor_export_platform.cpp b/editor/export/editor_export_platform.cpp
index b9dc52511e..67714d50a0 100644
--- a/editor/export/editor_export_platform.cpp
+++ b/editor/export/editor_export_platform.cpp
@@ -864,23 +864,19 @@ String EditorExportPlatform::_get_script_encryption_key(const Ref<EditorExportPr
 	return p_preset->get_script_encryption_key().to_lower();
 }
 
-Vector<String> EditorExportPlatform::get_forced_export_files() {
-	Vector<String> files;
-
-	files.push_back(ProjectSettings::get_singleton()->get_global_class_list_path());
+Vector<String> EditorExportPlatform::get_main_pack_forced_export_files() {
+	// First, get files required by any PCK.
+	Vector<String> files = get_forced_export_files();
 
 	String icon = GLOBAL_GET("application/config/icon");
-	String splash = GLOBAL_GET("application/boot_splash/image");
 	if (!icon.is_empty() && FileAccess::exists(icon)) {
 		files.push_back(icon);
 	}
-	if (!splash.is_empty() && FileAccess::exists(splash) && icon != splash) {
+
+	String splash = GLOBAL_GET("application/boot_splash/image");
+	if (!splash.is_empty() && icon != splash && FileAccess::exists(splash)) {
 		files.push_back(splash);
 	}
-	String resource_cache_file = ResourceUID::get_cache_file();
-	if (FileAccess::exists(resource_cache_file)) {
-		files.push_back(resource_cache_file);
-	}
 
 	String extension_list_config_file = GDExtension::get_extension_list_config_file();
 	if (FileAccess::exists(extension_list_config_file)) {
@@ -913,7 +909,19 @@ Vector<String> EditorExportPlatform::get_forced_export_files() {
 	return files;
 }
 
-Error EditorExportPlatform::export_project_files(const Ref<EditorExportPreset> &p_preset, bool p_debug, EditorExportSaveFunction p_func, void *p_udata, EditorExportSaveSharedObject p_so_func) {
+Vector<String> EditorExportPlatform::get_forced_export_files() {
+	Vector<String> files;
+	files.push_back(ProjectSettings::get_singleton()->get_global_class_list_path());
+
+	String resource_cache_file = ResourceUID::get_cache_file();
+	if (FileAccess::exists(resource_cache_file)) {
+		files.push_back(resource_cache_file);
+	}
+
+	return files;
+}
+
+Error EditorExportPlatform::export_project_files(bool p_main_pack, const Ref<EditorExportPreset> &p_preset, bool p_debug, EditorExportSaveFunction p_func, void *p_udata, EditorExportSaveSharedObject p_so_func) {
 	//figure out paths of files that will be exported
 	HashSet<String> paths;
 	Vector<String> path_remaps;
@@ -960,9 +968,11 @@ Error EditorExportPlatform::export_project_files(const Ref<EditorExportPreset> &
 		}
 	}
 
-	//add native icons to non-resource include list
-	_edit_filter_list(paths, String("*.icns"), false);
-	_edit_filter_list(paths, String("*.ico"), false);
+	if (p_main_pack) {
+		// Add native icons to non-resource include list.
+		_edit_filter_list(paths, String("*.icns"), false);
+		_edit_filter_list(paths, String("*.ico"), false);
+	}
 
 	_edit_filter_list(paths, p_preset->get_include_filter(), false);
 	_edit_filter_list(paths, p_preset->get_exclude_filter(), true);
@@ -1389,7 +1399,12 @@ Error EditorExportPlatform::export_project_files(const Ref<EditorExportPreset> &
 		}
 	}
 
-	Vector<String> forced_export = get_forced_export_files();
+	Vector<String> forced_export;
+	if (p_main_pack) {
+		forced_export = get_main_pack_forced_export_files();
+	} else {
+		forced_export = get_forced_export_files();
+	}
 	for (int i = 0; i < forced_export.size(); i++) {
 		Vector<uint8_t> array = FileAccess::get_file_as_bytes(forced_export[i]);
 		err = p_func(p_udata, forced_export[i], array, idx, total, enc_in_filters, enc_ex_filters, key);
@@ -1398,13 +1413,19 @@ Error EditorExportPlatform::export_project_files(const Ref<EditorExportPreset> &
 		}
 	}
 
-	String config_file = "project.binary";
-	String engine_cfb = EditorPaths::get_singleton()->get_cache_dir().path_join("tmp" + config_file);
-	ProjectSettings::get_singleton()->save_custom(engine_cfb, custom_map, custom_list);
-	Vector<uint8_t> data = FileAccess::get_file_as_bytes(engine_cfb);
-	DirAccess::remove_file_or_error(engine_cfb);
+	if (p_main_pack) {
+		String config_file = "project.binary";
+		String engine_cfb = EditorPaths::get_singleton()->get_cache_dir().path_join("tmp" + config_file);
+		ProjectSettings::get_singleton()->save_custom(engine_cfb, custom_map, custom_list);
+		Vector<uint8_t> data = FileAccess::get_file_as_bytes(engine_cfb);
+		DirAccess::remove_file_or_error(engine_cfb);
+		err = p_func(p_udata, "res://" + config_file, data, idx, total, enc_in_filters, enc_ex_filters, key);
+		if (err != OK) {
+			return err;
+		}
+	}
 
-	return p_func(p_udata, "res://" + config_file, data, idx, total, enc_in_filters, enc_ex_filters, key);
+	return OK;
 }
 
 Error EditorExportPlatform::_add_shared_object(void *p_userdata, const SharedObject &p_so) {
@@ -1533,7 +1554,7 @@ void EditorExportPlatform::zip_folder_recursive(zipFile &p_zip, const String &p_
 	da->list_dir_end();
 }
 
-Error EditorExportPlatform::save_pack(const Ref<EditorExportPreset> &p_preset, bool p_debug, const String &p_path, Vector<SharedObject> *p_so_files, bool p_embed, int64_t *r_embedded_start, int64_t *r_embedded_size) {
+Error EditorExportPlatform::save_pack(bool p_main_pack, const Ref<EditorExportPreset> &p_preset, bool p_debug, const String &p_path, Vector<SharedObject> *p_so_files, bool p_embed, int64_t *r_embedded_start, int64_t *r_embedded_size) {
 	EditorProgress ep("savepack", TTR("Packing"), 102, true);
 
 	// Create the temporary export directory if it doesn't exist.
@@ -1552,7 +1573,7 @@ Error EditorExportPlatform::save_pack(const Ref<EditorExportPreset> &p_preset, b
 	pd.f = ftmp;
 	pd.so_files = p_so_files;
 
-	Error err = export_project_files(p_preset, p_debug, _save_pack_file, &pd, _add_shared_object);
+	Error err = export_project_files(p_main_pack, p_preset, p_debug, _save_pack_file, &pd, _add_shared_object);
 
 	// Close temp file.
 	pd.f.unref();
@@ -1762,7 +1783,7 @@ Error EditorExportPlatform::save_zip(const Ref<EditorExportPreset> &p_preset, bo
 	zd.ep = &ep;
 	zd.zip = zip;
 
-	Error err = export_project_files(p_preset, p_debug, _save_zip_file, &zd);
+	Error err = export_project_files(false, p_preset, p_debug, _save_zip_file, &zd);
 	if (err != OK && err != ERR_SKIP) {
 		add_message(EXPORT_MESSAGE_ERROR, TTR("Save ZIP"), TTR("Failed to export project files."));
 	}
@@ -1774,7 +1795,7 @@ Error EditorExportPlatform::save_zip(const Ref<EditorExportPreset> &p_preset, bo
 
 Error EditorExportPlatform::export_pack(const Ref<EditorExportPreset> &p_preset, bool p_debug, const String &p_path, int p_flags) {
 	ExportNotifier notifier(*this, p_preset, p_debug, p_path, p_flags);
-	return save_pack(p_preset, p_debug, p_path);
+	return save_pack(false, p_preset, p_debug, p_path);
 }
 
 Error EditorExportPlatform::export_zip(const Ref<EditorExportPreset> &p_preset, bool p_debug, const String &p_path, int p_flags) {
diff --git a/editor/export/editor_export_platform.h b/editor/export/editor_export_platform.h
index 26e1f86c8b..4c4e64b1a6 100644
--- a/editor/export/editor_export_platform.h
+++ b/editor/export/editor_export_platform.h
@@ -203,6 +203,7 @@ public:
 		return worst_type;
 	}
 
+	static Vector<String> get_main_pack_forced_export_files();
 	static Vector<String> get_forced_export_files();
 
 	virtual bool fill_log_messages(RichTextLabel *p_log, Error p_err);
@@ -216,9 +217,9 @@ public:
 	virtual String get_name() const = 0;
 	virtual Ref<Texture2D> get_logo() const = 0;
 
-	Error export_project_files(const Ref<EditorExportPreset> &p_preset, bool p_debug, EditorExportSaveFunction p_func, void *p_udata, EditorExportSaveSharedObject p_so_func = nullptr);
+	Error export_project_files(bool p_main_pack, const Ref<EditorExportPreset> &p_preset, bool p_debug, EditorExportSaveFunction p_func, void *p_udata, EditorExportSaveSharedObject p_so_func = nullptr);
 
-	Error save_pack(const Ref<EditorExportPreset> &p_preset, bool p_debug, const String &p_path, Vector<SharedObject> *p_so_files = nullptr, bool p_embed = false, int64_t *r_embedded_start = nullptr, int64_t *r_embedded_size = nullptr);
+	Error save_pack(bool p_main_pack, const Ref<EditorExportPreset> &p_preset, bool p_debug, const String &p_path, Vector<SharedObject> *p_so_files = nullptr, bool p_embed = false, int64_t *r_embedded_start = nullptr, int64_t *r_embedded_size = nullptr);
 	Error save_zip(const Ref<EditorExportPreset> &p_preset, bool p_debug, const String &p_path);
 
 	virtual bool poll_export() { return false; }
diff --git a/editor/export/editor_export_platform_pc.cpp b/editor/export/editor_export_platform_pc.cpp
index 413db1595b..7cd8cb9b29 100644
--- a/editor/export/editor_export_platform_pc.cpp
+++ b/editor/export/editor_export_platform_pc.cpp
@@ -181,7 +181,7 @@ Error EditorExportPlatformPC::export_project_data(const Ref<EditorExportPreset>
 
 	int64_t embedded_pos;
 	int64_t embedded_size;
-	Error err = save_pack(p_preset, p_debug, pck_path, &so_files, p_preset->get("binary_format/embed_pck"), &embedded_pos, &embedded_size);
+	Error err = save_pack(true, p_preset, p_debug, pck_path, &so_files, p_preset->get("binary_format/embed_pck"), &embedded_pos, &embedded_size);
 	if (err == OK && p_preset->get("binary_format/embed_pck")) {
 		if (embedded_size >= 0x100000000 && String(p_preset->get("binary_format/architecture")).contains("32")) {
 			add_message(EXPORT_MESSAGE_ERROR, TTR("PCK Embedding"), TTR("On 32-bit exports the embedded PCK cannot be bigger than 4 GiB."));
diff --git a/editor/export/project_export.cpp b/editor/export/project_export.cpp
index 223900e8b3..cae814e77d 100644
--- a/editor/export/project_export.cpp
+++ b/editor/export/project_export.cpp
@@ -1039,6 +1039,8 @@ void ProjectExportDialog::_export_pck_zip_selected(const String &p_path) {
 		platform->export_zip(current, export_pck_zip_debug->is_pressed(), p_path);
 	} else if (p_path.ends_with(".pck")) {
 		platform->export_pack(current, export_pck_zip_debug->is_pressed(), p_path);
+	} else {
+		ERR_FAIL_MSG("Path must end with .pck or .zip");
 	}
 }
 
diff --git a/main/main.cpp b/main/main.cpp
index ec66d47901..15f55fe180 100644
--- a/main/main.cpp
+++ b/main/main.cpp
@@ -1771,7 +1771,7 @@ Error Main::setup(const char *execpath, int argc, char *argv[], bool p_second_ph
 	initialize_modules(MODULE_INITIALIZATION_LEVEL_CORE);
 	register_core_extensions(); // core extensions must be registered after globals setup and before display
 
-	ResourceUID::get_singleton()->load_from_cache(); // load UUIDs from cache.
+	ResourceUID::get_singleton()->load_from_cache(true); // load UUIDs from cache.
 
 	if (ProjectSettings::get_singleton()->has_custom_feature("dedicated_server")) {
 		audio_driver = NULL_AUDIO_DRIVER;
diff --git a/platform/android/export/export_plugin.cpp b/platform/android/export/export_plugin.cpp
index 74d22bc44f..894c13cc0b 100644
--- a/platform/android/export/export_plugin.cpp
+++ b/platform/android/export/export_plugin.cpp
@@ -2643,7 +2643,7 @@ String EditorExportPlatformAndroid::get_apk_expansion_fullpath(const Ref<EditorE
 
 Error EditorExportPlatformAndroid::save_apk_expansion_file(const Ref<EditorExportPreset> &p_preset, bool p_debug, const String &p_path) {
 	String fullpath = get_apk_expansion_fullpath(p_preset, p_path);
-	Error err = save_pack(p_preset, p_debug, fullpath);
+	Error err = save_pack(false, p_preset, p_debug, fullpath);
 	return err;
 }
 
@@ -3087,9 +3087,9 @@ Error EditorExportPlatformAndroid::export_project_helper(const Ref<EditorExportP
 			user_data.libs_directory = gradle_build_directory.path_join("libs");
 			user_data.debug = p_debug;
 			if (p_flags & DEBUG_FLAG_DUMB_CLIENT) {
-				err = export_project_files(p_preset, p_debug, ignore_apk_file, &user_data, copy_gradle_so);
+				err = export_project_files(true, p_preset, p_debug, ignore_apk_file, &user_data, copy_gradle_so);
 			} else {
-				err = export_project_files(p_preset, p_debug, rename_and_store_file_in_gradle_project, &user_data, copy_gradle_so);
+				err = export_project_files(true, p_preset, p_debug, rename_and_store_file_in_gradle_project, &user_data, copy_gradle_so);
 			}
 			if (err != OK) {
 				add_message(EXPORT_MESSAGE_ERROR, TTR("Export"), TTR("Could not export project files to gradle project."));
@@ -3474,7 +3474,7 @@ Error EditorExportPlatformAndroid::export_project_helper(const Ref<EditorExportP
 		APKExportData ed;
 		ed.ep = &ep;
 		ed.apk = unaligned_apk;
-		err = export_project_files(p_preset, p_debug, ignore_apk_file, &ed, save_apk_so);
+		err = export_project_files(true, p_preset, p_debug, ignore_apk_file, &ed, save_apk_so);
 	} else {
 		if (apk_expansion) {
 			err = save_apk_expansion_file(p_preset, p_debug, p_path);
@@ -3486,7 +3486,7 @@ Error EditorExportPlatformAndroid::export_project_helper(const Ref<EditorExportP
 			APKExportData ed;
 			ed.ep = &ep;
 			ed.apk = unaligned_apk;
-			err = export_project_files(p_preset, p_debug, save_apk_file, &ed, save_apk_so);
+			err = export_project_files(true, p_preset, p_debug, save_apk_file, &ed, save_apk_so);
 		}
 	}
 
diff --git a/platform/ios/export/export_plugin.cpp b/platform/ios/export/export_plugin.cpp
index 91d75b0629..45baf97e9a 100644
--- a/platform/ios/export/export_plugin.cpp
+++ b/platform/ios/export/export_plugin.cpp
@@ -1653,7 +1653,7 @@ Error EditorExportPlatformIOS::_export_project_helper(const Ref<EditorExportPres
 	}
 	String pack_path = binary_dir + ".pck";
 	Vector<SharedObject> libraries;
-	Error err = save_pack(p_preset, p_debug, pack_path, &libraries);
+	Error err = save_pack(true, p_preset, p_debug, pack_path, &libraries);
 	if (err) {
 		// Message is supplied by the subroutine method.
 		return err;
diff --git a/platform/macos/export/export_plugin.cpp b/platform/macos/export/export_plugin.cpp
index 9cc57e4066..05ae4a74c9 100644
--- a/platform/macos/export/export_plugin.cpp
+++ b/platform/macos/export/export_plugin.cpp
@@ -1768,7 +1768,7 @@ Error EditorExportPlatformMacOS::export_project(const Ref<EditorExportPreset> &p
 
 		String pack_path = tmp_app_path_name + "/Contents/Resources/" + pkg_name + ".pck";
 		Vector<SharedObject> shared_objects;
-		err = save_pack(p_preset, p_debug, pack_path, &shared_objects);
+		err = save_pack(true, p_preset, p_debug, pack_path, &shared_objects);
 
 		bool lib_validation = p_preset->get("codesign/entitlements/disable_library_validation");
 		if (!shared_objects.is_empty() && sign_enabled && ad_hoc && !lib_validation) {
diff --git a/platform/web/export/export_plugin.cpp b/platform/web/export/export_plugin.cpp
index 41c969b5f4..ec7f599507 100644
--- a/platform/web/export/export_plugin.cpp
+++ b/platform/web/export/export_plugin.cpp
@@ -479,7 +479,7 @@ Error EditorExportPlatformWeb::export_project(const Ref<EditorExportPreset> &p_p
 	// Export pck and shared objects
 	Vector<SharedObject> shared_objects;
 	String pck_path = base_path + ".pck";
-	Error error = save_pack(p_preset, p_debug, pck_path, &shared_objects);
+	Error error = save_pack(true, p_preset, p_debug, pck_path, &shared_objects);
 	if (error != OK) {
 		add_message(EXPORT_MESSAGE_ERROR, TTR("Export"), vformat(TTR("Could not write file: \"%s\"."), pck_path));
 		return error;