Fix custom resource icons not appearing in file system

core/io/resource.cpp

@@ -320,6 +320,11 @@ void Resource::notify_change_to_owners() {
 	}
 }
 
+// We assume that only Resources can have attached scripts (excluding Scripts and PackedScenes, which still extend Resource).
+bool Resource::is_script_extendable_resource(const StringName &p_class) {
+	return ClassDB::is_parent_class(p_class, Resource::get_class_static()) && !ClassDB::is_parent_class(p_class, Script::get_class_static()) && !ClassDB::is_parent_class(p_class, "PackedScene");
+}
+
 #ifdef TOOLS_ENABLED
 
 uint32_t Resource::hash_edited_version() const {

core/io/resource.h

@@ -120,6 +120,7 @@ class Resource : public RefCounted {
 
 	Node *get_local_scene() const;
 
+	static bool is_script_extendable_resource(const StringName &p_class);
 #ifdef TOOLS_ENABLED
 
 	uint32_t hash_edited_version() const;

core/io/resource_format_binary.cpp

@@ -904,6 +904,47 @@ String ResourceLoaderBinary::get_unicode_string() {
 	return s;
 }
 
+String ResourceLoaderBinary::get_attached_script_path(Ref<FileAccess> p_f) {
+	open(p_f, false, true);
+	if (error) {
+		return "";
+	}
+	int main_resource_idx = internal_resources.size() - 1;
+
+	uint64_t offset = internal_resources[main_resource_idx].offset;
+
+	f->seek(offset);
+
+	String t = get_unicode_string();
+
+	int pc = f->get_32();
+	for (int j = 0; j < pc; j++) {
+		StringName name = _get_string();
+
+		if (name == StringName()) {
+			error = ERR_FILE_CORRUPT;
+			ERR_FAIL_V("");
+		}
+
+		Variant value;
+		uint32_t type = f->get_32();
+		// Note that OBJECT_EXTERNAL_RESOURCE is old resource file format
+		if (name != StringName("script") || type != VARIANT_OBJECT) {
+			return "";
+		}
+
+		uint32_t objtype = f->get_32();
+		if (objtype != OBJECT_EXTERNAL_RESOURCE_INDEX) {
+			return "";
+		}
+
+		int erindex = f->get_32();
+		return external_resources[erindex].path;
+	}
+
+	return "";
+}
+
 void ResourceLoaderBinary::get_classes_used(Ref<FileAccess> p_f, HashSet<StringName> *p_classes) {
 	open(p_f, false, true);
 	if (error) {
@@ -1175,6 +1216,21 @@ bool ResourceFormatLoaderBinary::handles_type(const String &p_type) const {
 	return true; //handles all
 }
 
+String ResourceFormatLoaderBinary::get_attached_script_path(const String &p_path) const {
+	String type = get_resource_type(p_path);
+	if (!Resource::is_script_extendable_resource(type)) {
+		return "";
+	}
+
+	Ref<FileAccess> f = FileAccess::open(p_path, FileAccess::READ);
+	ERR_FAIL_COND_V_MSG(f.is_null(), "", "Cannot open file '" + p_path + "'.");
+
+	ResourceLoaderBinary loader;
+	loader.local_path = ProjectSettings::get_singleton()->localize_path(p_path);
+	loader.res_path = loader.local_path;
+	return loader.get_attached_script_path(f);
+}
+
 void ResourceFormatLoaderBinary::get_dependencies(const String &p_path, List<String> *p_dependencies, bool p_add_types) {
 	Ref<FileAccess> f = FileAccess::open(p_path, FileAccess::READ);
 	ERR_FAIL_COND_MSG(f.is_null(), "Cannot open file '" + p_path + "'.");

core/io/resource_format_binary.h

@@ -100,6 +100,7 @@ class ResourceLoaderBinary {
 	void set_remaps(const HashMap<String, String> &p_remaps) { remaps = p_remaps; }
 	void open(Ref<FileAccess> p_f, bool p_no_resources = false, bool p_keep_uuid_paths = false);
 	String recognize(Ref<FileAccess> p_f);
+	String get_attached_script_path(Ref<FileAccess> p_f);
 	void get_dependencies(Ref<FileAccess> p_f, List<String> *p_dependencies, bool p_add_types);
 	void get_classes_used(Ref<FileAccess> p_f, HashSet<StringName> *p_classes);
 
@@ -115,6 +116,7 @@ class ResourceFormatLoaderBinary : public ResourceFormatLoader {
 	virtual String get_resource_type(const String &p_path) const;
 	virtual void get_classes_used(const String &p_path, HashSet<StringName> *r_classes);
 	virtual ResourceUID::ID get_resource_uid(const String &p_path) const;
+	virtual String get_attached_script_path(const String &p_path) const;
 	virtual void get_dependencies(const String &p_path, List<String> *p_dependencies, bool p_add_types = false);
 	virtual Error rename_dependencies(const String &p_path, const HashMap<String, String> &p_map);
 };

core/io/resource_loader.cpp

@@ -101,6 +101,15 @@ String ResourceFormatLoader::get_resource_type(const String &p_path) const {
 	return "";
 }
 
+String ResourceFormatLoader::get_attached_script_path(const String &p_path) const {
+	String script_path;
+	if (GDVIRTUAL_CALL(_get_attached_script_path, p_path, script_path)) {
+		return script_path;
+	}
+
+	return "";
+}
+
 ResourceUID::ID ResourceFormatLoader::get_resource_uid(const String &p_path) const {
 	int64_t uid;
 	if (GDVIRTUAL_CALL(_get_resource_uid, p_path, uid)) {
@@ -191,6 +200,7 @@ void ResourceFormatLoader::_bind_methods() {
 	GDVIRTUAL_BIND(_get_recognized_extensions);
 	GDVIRTUAL_BIND(_handles_type, "type");
 	GDVIRTUAL_BIND(_get_resource_type, "path");
+	GDVIRTUAL_BIND(_get_attached_script_path, "path");
 	GDVIRTUAL_BIND(_get_resource_uid, "path");
 	GDVIRTUAL_BIND(_get_dependencies, "path", "add_types");
 	GDVIRTUAL_BIND(_rename_dependencies, "path", "renames");
@@ -784,6 +794,19 @@ ResourceUID::ID ResourceLoader::get_resource_uid(const String &p_path) {
 	return ResourceUID::INVALID_ID;
 }
 
+String ResourceLoader::get_attached_script_path(const String &p_path) {
+	String local_path = _validate_local_path(p_path);
+
+	for (int i = 0; i < loader_count; i++) {
+		String path = loader[i]->get_attached_script_path(local_path);
+		if (!path.is_empty()) {
+			return path;
+		}
+	}
+
+	return "";
+}
+
 String ResourceLoader::_path_remap(const String &p_path, bool *r_translation_remapped) {
 	String new_path = p_path;
 

core/io/resource_loader.h

@@ -53,6 +53,7 @@ class ResourceFormatLoader : public RefCounted {
 	GDVIRTUAL0RC(Vector<String>, _get_recognized_extensions)
 	GDVIRTUAL1RC(bool, _handles_type, StringName)
 	GDVIRTUAL1RC(String, _get_resource_type, String)
+	GDVIRTUAL1RC(String, _get_attached_script_path, String)
 	GDVIRTUAL1RC(ResourceUID::ID, _get_resource_uid, String)
 	GDVIRTUAL2RC(Vector<String>, _get_dependencies, String, bool)
 	GDVIRTUAL1RC(Vector<String>, _get_classes_used, String)
@@ -70,6 +71,7 @@ class ResourceFormatLoader : public RefCounted {
 	virtual bool handles_type(const String &p_type) const;
 	virtual void get_classes_used(const String &p_path, HashSet<StringName> *r_classes);
 	virtual String get_resource_type(const String &p_path) const;
+	virtual String get_attached_script_path(const String &p_path) const;
 	virtual ResourceUID::ID get_resource_uid(const String &p_path) const;
 	virtual void get_dependencies(const String &p_path, List<String> *p_dependencies, bool p_add_types = false);
 	virtual Error rename_dependencies(const String &p_path, const HashMap<String, String> &p_map);
@@ -175,6 +177,7 @@ class ResourceLoader {
 	static void get_classes_used(const String &p_path, HashSet<StringName> *r_classes);
 	static String get_resource_type(const String &p_path);
 	static ResourceUID::ID get_resource_uid(const String &p_path);
+	static String get_attached_script_path(const String &p_path);
 	static void get_dependencies(const String &p_path, List<String> *p_dependencies, bool p_add_types = false);
 	static Error rename_dependencies(const String &p_path, const HashMap<String, String> &p_map);
 	static bool is_import_valid(const String &p_path);

core/object/class_db.h

@@ -232,6 +232,7 @@ class ClassDB {
 	static StringName get_compatibility_remapped_class(const StringName &p_class);
 	static bool class_exists(const StringName &p_class);
 	static bool is_parent_class(const StringName &p_class, const StringName &p_inherits);
+
 	static bool can_instantiate(const StringName &p_class);
 	static bool is_virtual(const StringName &p_class);
 	static Object *instantiate(const StringName &p_class);

core/variant/variant_parser.cpp

@@ -1399,6 +1399,21 @@ Error VariantParser::_parse_tag(Token &token, Stream *p_stream, int &line, Strin
 	return OK;
 }
 
+Error VariantParser::skip_until_tag(Stream *p_stream, int &line, String &r_err_str, Tag &r_tag, ResourceParser *p_res_parser, bool p_simple_tag) {
+	Token token;
+	get_token(p_stream, token, line, r_err_str);
+
+	if (token.type == TK_EOF) {
+		return ERR_FILE_EOF;
+	}
+
+	while (token.type != TK_BRACKET_OPEN) {
+		get_token(p_stream, token, line, r_err_str);
+	}
+
+	return _parse_tag(token, p_stream, line, r_err_str, r_tag, p_res_parser, p_simple_tag);
+}
+
 Error VariantParser::parse_tag(Stream *p_stream, int &line, String &r_err_str, Tag &r_tag, ResourceParser *p_res_parser, bool p_simple_tag) {
 	Token token;
 	get_token(p_stream, token, line, r_err_str);
@@ -1415,8 +1430,8 @@ Error VariantParser::parse_tag(Stream *p_stream, int &line, String &r_err_str, T
 	return _parse_tag(token, p_stream, line, r_err_str, r_tag, p_res_parser, p_simple_tag);
 }
 
-Error VariantParser::parse_tag_assign_eof(Stream *p_stream, int &line, String &r_err_str, Tag &r_tag, String &r_assign, Variant &r_value, ResourceParser *p_res_parser, bool p_simple_tag) {
-	//assign..
+// Parses tags or assigns and takes in a custom function for handling value parsing
+Error VariantParser::parse_tag_assign_with_value_func_eof(Stream *p_stream, int &line, String &r_err_str, Tag &r_tag, String &r_assign, Variant &r_value, ResourceParser *p_res_parser, bool p_simple_tag, ParseValueFunc p_parse_value_func) {
 	r_assign = "";
 	String what;
 
@@ -1478,7 +1493,7 @@ Error VariantParser::parse_tag_assign_eof(Stream *p_stream, int &line, String &r
 				r_assign = what;
 				Token token;
 				get_token(p_stream, token, line, r_err_str);
-				Error err = parse_value(token, r_value, p_stream, line, r_err_str, p_res_parser);
+				Error err = p_parse_value_func(token, r_value, p_stream, line, r_err_str, p_res_parser);
 				return err;
 			}
 		} else if (c == '\n') {
@@ -1487,6 +1502,10 @@ Error VariantParser::parse_tag_assign_eof(Stream *p_stream, int &line, String &r
 	}
 }
 
+Error VariantParser::parse_tag_assign_eof(Stream *p_stream, int &line, String &r_err_str, Tag &r_tag, String &r_assign, Variant &r_value, ResourceParser *p_res_parser, bool p_simple_tag) {
+	return parse_tag_assign_with_value_func_eof(p_stream, line, r_err_str, r_tag, r_assign, r_value, p_res_parser, p_simple_tag, parse_value);
+}
+
 Error VariantParser::parse(Stream *p_stream, Variant &r_ret, String &r_err_str, int &r_err_line, ResourceParser *p_res_parser) {
 	Token token;
 	Error err = get_token(p_stream, token, r_err_line, r_err_str);

core/variant/variant_parser.h

@@ -127,7 +127,11 @@ class VariantParser {
 	static Error _parse_tag(Token &token, Stream *p_stream, int &line, String &r_err_str, Tag &r_tag, ResourceParser *p_res_parser = nullptr, bool p_simple_tag = false);
 
 public:
+	typedef Error (*ParseValueFunc)(Token &token, Variant &value, Stream *p_stream, int &line, String &r_err_str, ResourceParser *p_res_parser);
+
+	static Error skip_until_tag(Stream *p_stream, int &line, String &r_err_str, Tag &r_tag, ResourceParser *p_res_parser = nullptr, bool p_simple_tag = false);
 	static Error parse_tag(Stream *p_stream, int &line, String &r_err_str, Tag &r_tag, ResourceParser *p_res_parser = nullptr, bool p_simple_tag = false);
+	static Error parse_tag_assign_with_value_func_eof(Stream *p_stream, int &line, String &r_err_str, Tag &r_tag, String &r_assign, Variant &r_value, ResourceParser *p_res_parser, bool p_simple_tag, ParseValueFunc p_value_func);
 	static Error parse_tag_assign_eof(Stream *p_stream, int &line, String &r_err_str, Tag &r_tag, String &r_assign, Variant &r_value, ResourceParser *p_res_parser = nullptr, bool p_simple_tag = false);
 
 	static Error parse_value(Token &token, Variant &value, Stream *p_stream, int &line, String &r_err_str, ResourceParser *p_res_parser = nullptr);

doc/classes/EditorFileSystem.xml

@@ -96,6 +96,11 @@
 				Emitted if at least one resource is reloaded when the filesystem is scanned.
 			</description>
 		</signal>
+		<signal name="script_classes_loaded">
+			<description>
+				Emitted once all scripts have been loaded. This happens after [signal filesystem_changed] is emitted.
+			</description>
+		</signal>
 		<signal name="sources_changed">
 			<param index="0" name="exist" type="bool" />
 			<description>

doc/classes/ResourceFormatLoader.xml

@@ -17,6 +17,13 @@
 			<description>
 			</description>
 		</method>
+		<method name="_get_attached_script_path" qualifiers="virtual const">
+			<return type="String" />
+			<param index="0" name="path" type="String" />
+			<description>
+				If implemented, gets the path of a script attached to a resource. The script is usually attached when creating a new instance of a [Resource]-based custom class.
+			</description>
+		</method>
 		<method name="_get_classes_used" qualifiers="virtual const">
 			<return type="PackedStringArray" />
 			<param index="0" name="path" type="String" />