GDScript: Fix common mismatched external parser errors

2 files changed, 124 insertions, 35 deletions

diff --git a/modules/gdscript/gdscript_analyzer.cpp b/modules/gdscript/gdscript_analyzer.cpp
index 67b40a6198..6548650a48 100644
--- a/modules/gdscript/gdscript_analyzer.cpp
+++ b/modules/gdscript/gdscript_analyzer.cpp
@@ -312,6 +312,15 @@ Error GDScriptAnalyzer::resolve_class_inheritance(GDScriptParser::ClassNode *p_c
 		p_source = p_class;
 	}
 
+	Ref<GDScriptParserRef> parser_ref = ensure_cached_parser_for_class(p_class, nullptr, vformat(R"(Trying to resolve class inheritance of "%s" from "%s")", p_class->fqcn, parser->script_path), p_source);
+	Finally finally([&]() {
+		GDScriptParser::ClassNode *look_class = p_class;
+		do {
+			ensure_cached_parser_for_class(look_class->base_type.class_type, look_class, vformat(R"(Trying to resolve class inheritance of "%s" from "%s")", p_class->fqcn, parser->script_path), p_source);
+			look_class = look_class->base_type.class_type;
+		} while (look_class != nullptr);
+	});
+
 	if (p_class->base_type.is_resolving()) {
 		push_error(vformat(R"(Could not resolve class "%s": Cyclic reference.)", type_from_metatype(p_class->get_datatype()).to_string()), p_source);
 		return ERR_PARSE_ERROR;
@@ -323,21 +332,17 @@ Error GDScriptAnalyzer::resolve_class_inheritance(GDScriptParser::ClassNode *p_c
 	}
 
 	if (!parser->has_class(p_class)) {
-		String script_path = p_class->get_datatype().script_path;
-		Ref<GDScriptParserRef> parser_ref = parser->get_depended_parser_for(script_path);
 		if (parser_ref.is_null()) {
-			push_error(vformat(R"(Could not find script "%s".)", script_path), p_source);
+			// Error already pushed.
 			return ERR_PARSE_ERROR;
 		}
 
 		Error err = parser_ref->raise_status(GDScriptParserRef::PARSED);
 		if (err) {
-			push_error(vformat(R"(Could not parse script "%s": %s.)", script_path, error_names[err]), p_source);
+			push_error(vformat(R"(Could not parse script "%s": %s.)", p_class->get_datatype().script_path, error_names[err]), p_source);
 			return ERR_PARSE_ERROR;
 		}
 
-		ERR_FAIL_COND_V_MSG(!parser_ref->get_parser()->has_class(p_class), ERR_PARSE_ERROR, R"(Parser bug: Mismatched external parser.)");
-
 		GDScriptAnalyzer *other_analyzer = parser_ref->get_analyzer();
 		GDScriptParser *other_parser = parser_ref->get_parser();
 
@@ -883,6 +888,11 @@ void GDScriptAnalyzer::resolve_class_member(GDScriptParser::ClassNode *p_class,
 		p_source = member.get_source_node();
 	}
 
+	Ref<GDScriptParserRef> parser_ref = ensure_cached_parser_for_class(p_class, nullptr, vformat(R"(Trying to resolve class member "%s" of "%s" from "%s")", member.get_name(), p_class->fqcn, parser->script_path), p_source);
+	Finally finally([&]() {
+		ensure_cached_parser_for_class(member.get_datatype().class_type, p_class, vformat(R"(Trying to resolve class member "%s" of "%s" from "%s")", member.get_name(), p_class->fqcn, parser->script_path), p_source);
+	});
+
 	if (member.get_datatype().is_resolving()) {
 		push_error(vformat(R"(Could not resolve member "%s": Cyclic reference.)", member.get_name()), p_source);
 		return;
@@ -892,22 +902,26 @@ void GDScriptAnalyzer::resolve_class_member(GDScriptParser::ClassNode *p_class,
 		return;
 	}
 
+	// If it's already resolving, that's ok.
+	if (!p_class->base_type.is_resolving()) {
+		Error err = resolve_class_inheritance(p_class);
+		if (err) {
+			return;
+		}
+	}
+
 	if (!parser->has_class(p_class)) {
-		String script_path = p_class->get_datatype().script_path;
-		Ref<GDScriptParserRef> parser_ref = parser->get_depended_parser_for(script_path);
 		if (parser_ref.is_null()) {
-			push_error(vformat(R"(Could not find script "%s" (While resolving "%s").)", script_path, member.get_name()), p_source);
+			// Error already pushed.
 			return;
 		}
 
 		Error err = parser_ref->raise_status(GDScriptParserRef::PARSED);
 		if (err) {
-			push_error(vformat(R"(Could not resolve script "%s": %s (While resolving "%s").)", script_path, error_names[err], member.get_name()), p_source);
+			push_error(vformat(R"(Could not parse script "%s": %s (While resolving member "%s").)", p_class->get_datatype().script_path, error_names[err], member.get_name()), p_source);
 			return;
 		}
 
-		ERR_FAIL_COND_MSG(!parser_ref->get_parser()->has_class(p_class), R"(Parser bug: Mismatched external parser.)");
-
 		GDScriptAnalyzer *other_analyzer = parser_ref->get_analyzer();
 		GDScriptParser *other_parser = parser_ref->get_parser();
 
@@ -915,19 +929,12 @@ void GDScriptAnalyzer::resolve_class_member(GDScriptParser::ClassNode *p_class,
 		other_analyzer->resolve_class_member(p_class, p_index);
 		if (other_parser->errors.size() > error_count) {
 			push_error(vformat(R"(Could not resolve member "%s".)", member.get_name()), p_source);
+			return;
 		}
 
 		return;
 	}
 
-	// If it's already resolving, that's ok.
-	if (!p_class->base_type.is_resolving()) {
-		Error err = resolve_class_inheritance(p_class);
-		if (err) {
-			return;
-		}
-	}
-
 	GDScriptParser::ClassNode *previous_class = parser->current_class;
 	parser->current_class = p_class;
 
@@ -1170,27 +1177,25 @@ void GDScriptAnalyzer::resolve_class_interface(GDScriptParser::ClassNode *p_clas
 		p_source = p_class;
 	}
 
+	Ref<GDScriptParserRef> parser_ref = ensure_cached_parser_for_class(p_class, nullptr, vformat(R"(Trying to resolve class interface of "%s" from "%s")", p_class->fqcn, parser->script_path), p_source);
+
 	if (!p_class->resolved_interface) {
 #ifdef DEBUG_ENABLED
 		bool has_static_data = p_class->has_static_data;
 #endif
 
 		if (!parser->has_class(p_class)) {
-			String script_path = p_class->get_datatype().script_path;
-			Ref<GDScriptParserRef> parser_ref = parser->get_depended_parser_for(script_path);
 			if (parser_ref.is_null()) {
-				push_error(vformat(R"(Could not find script "%s".)", script_path), p_source);
+				// Error already pushed.
 				return;
 			}
 
 			Error err = parser_ref->raise_status(GDScriptParserRef::PARSED);
 			if (err) {
-				push_error(vformat(R"(Could not resolve script "%s": %s.)", script_path, error_names[err]), p_source);
+				push_error(vformat(R"(Could not parse script "%s": %s.)", p_class->get_datatype().script_path, error_names[err]), p_source);
 				return;
 			}
 
-			ERR_FAIL_COND_MSG(!parser_ref->get_parser()->has_class(p_class), R"(Parser bug: Mismatched external parser.)");
-
 			GDScriptAnalyzer *other_analyzer = parser_ref->get_analyzer();
 			GDScriptParser *other_parser = parser_ref->get_parser();
 
@@ -1198,6 +1203,7 @@ void GDScriptAnalyzer::resolve_class_interface(GDScriptParser::ClassNode *p_clas
 			other_analyzer->resolve_class_interface(p_class);
 			if (other_parser->errors.size() > error_count) {
 				push_error(vformat(R"(Could not resolve class "%s".)", p_class->fqcn), p_source);
+				return;
 			}
 
 			return;
@@ -1261,26 +1267,24 @@ void GDScriptAnalyzer::resolve_class_body(GDScriptParser::ClassNode *p_class, co
 		p_source = p_class;
 	}
 
+	Ref<GDScriptParserRef> parser_ref = ensure_cached_parser_for_class(p_class, nullptr, vformat(R"(Trying to resolve class body of "%s" from "%s")", p_class->fqcn, parser->script_path), p_source);
+
 	if (p_class->resolved_body) {
 		return;
 	}
 
 	if (!parser->has_class(p_class)) {
-		String script_path = p_class->get_datatype().script_path;
-		Ref<GDScriptParserRef> parser_ref = parser->get_depended_parser_for(script_path);
 		if (parser_ref.is_null()) {
-			push_error(vformat(R"(Could not find script "%s".)", script_path), p_source);
+			// Error already pushed.
 			return;
 		}
 
 		Error err = parser_ref->raise_status(GDScriptParserRef::PARSED);
 		if (err) {
-			push_error(vformat(R"(Could not resolve script "%s": %s.)", script_path, error_names[err]), p_source);
+			push_error(vformat(R"(Could not parse script "%s": %s.)", p_class->get_datatype().script_path, error_names[err]), p_source);
 			return;
 		}
 
-		ERR_FAIL_COND_MSG(!parser_ref->get_parser()->has_class(p_class), R"(Parser bug: Mismatched external parser.)");
-
 		GDScriptAnalyzer *other_analyzer = parser_ref->get_analyzer();
 		GDScriptParser *other_parser = parser_ref->get_parser();
 
@@ -1288,6 +1292,7 @@ void GDScriptAnalyzer::resolve_class_body(GDScriptParser::ClassNode *p_class, co
 		other_analyzer->resolve_class_body(p_class);
 		if (other_parser->errors.size() > error_count) {
 			push_error(vformat(R"(Could not resolve class "%s".)", p_class->fqcn), p_source);
+			return;
 		}
 
 		return;
@@ -3645,12 +3650,81 @@ GDScriptParser::DataType GDScriptAnalyzer::make_global_class_meta_type(const Str
 	}
 }
 
+Ref<GDScriptParserRef> GDScriptAnalyzer::ensure_cached_parser_for_class(const GDScriptParser::ClassNode *p_class, const GDScriptParser::ClassNode *p_from_class, const String &p_context, const GDScriptParser::Node *p_source) {
+	if (p_class == nullptr) {
+		return nullptr;
+	}
+
+	if (parser->has_class(p_class)) {
+		return nullptr;
+	}
+
+	{
+		HashMap<const GDScriptParser::ClassNode *, Ref<GDScriptParserRef>>::Iterator E = external_class_parser_cache.find(p_class);
+		if (E) {
+			return E->value;
+		}
+	}
+
+	Ref<GDScriptParserRef> parser_ref;
+	Ref<GDScriptParserRef> dependant_parser_ref;
+	GDScriptParser *dependant_parser = parser;
+	do {
+		if (HashMap<const GDScriptParser::ClassNode *, Ref<GDScriptParserRef>>::Iterator E = external_class_parser_cache.find(p_from_class)) {
+			dependant_parser_ref = E->value;
+			dependant_parser = E->value->get_parser();
+
+			// Silently ensure it's parsed.
+			dependant_parser_ref->raise_status(GDScriptParserRef::PARSED);
+		}
+
+		if (dependant_parser == nullptr) {
+			continue;
+		}
+
+		if (dependant_parser_ref.is_valid() && dependant_parser->has_class(p_class)) {
+			external_class_parser_cache.insert(p_class, dependant_parser_ref);
+			parser_ref = dependant_parser_ref;
+			break;
+		}
+
+		String script_path = p_class->get_datatype().script_path;
+		HashMap<String, Ref<GDScriptParserRef>>::Iterator E = dependant_parser->depended_parsers.find(script_path);
+		if (E) {
+			// Silently ensure it's parsed.
+			E->value->raise_status(GDScriptParserRef::PARSED);
+			if (E->value->get_parser()->has_class(p_class)) {
+				external_class_parser_cache.insert(p_class, E->value);
+				parser_ref = E->value;
+				break;
+			}
+		}
+
+		dependant_parser_ref = Ref<GDScriptParserRef>();
+		dependant_parser = nullptr;
+		p_from_class = p_from_class->base_type.class_type;
+	} while (p_from_class != nullptr);
+
+	if (parser_ref.is_null()) {
+		push_error(vformat(R"(Parser bug: Could not find external parser. (%s))", p_context), p_source);
+	}
+
+	return parser_ref;
+}
+
+Ref<GDScript> GDScriptAnalyzer::get_depended_shallow_script(const String &p_path, Error &r_error) {
+	// To keep a local cache of the parser for resolving external nodes later.
+	parser->get_depended_parser_for(p_path);
+	Ref<GDScript> scr = GDScriptCache::get_shallow_script(p_path, r_error, parser->script_path);
+	return scr;
+}
+
 void GDScriptAnalyzer::reduce_identifier_from_base_set_class(GDScriptParser::IdentifierNode *p_identifier, GDScriptParser::DataType p_identifier_datatype) {
 	ERR_FAIL_NULL(p_identifier);
 
 	p_identifier->set_datatype(p_identifier_datatype);
 	Error err = OK;
-	Ref<GDScript> scr = GDScriptCache::get_shallow_script(p_identifier_datatype.script_path, err, parser->script_path);
+	Ref<GDScript> scr = get_depended_shallow_script(p_identifier_datatype.script_path, err);
 	if (err) {
 		push_error(vformat(R"(Error while getting cache for script "%s".)", p_identifier_datatype.script_path), p_identifier);
 		return;
@@ -4340,7 +4414,7 @@ void GDScriptAnalyzer::reduce_preload(GDScriptParser::PreloadNode *p_preload) {
 			const String &res_type = ResourceLoader::get_resource_type(p_preload->resolved_path);
 			if (res_type == "GDScript") {
 				Error err = OK;
-				Ref<GDScript> res = GDScriptCache::get_shallow_script(p_preload->resolved_path, err, parser->script_path);
+				Ref<GDScript> res = get_depended_shallow_script(p_preload->resolved_path, err);
 				p_preload->resource = res;
 				if (err != OK) {
 					push_error(vformat(R"(Could not preload resource script "%s".)", p_preload->resolved_path), p_preload->path);
@@ -4916,7 +4990,7 @@ Array GDScriptAnalyzer::make_array_from_element_datatype(const GDScriptParser::D
 		Ref<Script> script_type = p_element_datatype.script_type;
 		if (p_element_datatype.kind == GDScriptParser::DataType::CLASS && script_type.is_null()) {
 			Error err = OK;
-			Ref<GDScript> scr = GDScriptCache::get_shallow_script(p_element_datatype.script_path, err, parser->script_path);
+			Ref<GDScript> scr = get_depended_shallow_script(p_element_datatype.script_path, err);
 			if (err) {
 				push_error(vformat(R"(Error while getting cache for script "%s".)", p_element_datatype.script_path), p_source_node);
 				return array;
diff --git a/modules/gdscript/gdscript_analyzer.h b/modules/gdscript/gdscript_analyzer.h
index 922000df52..35e20f40d4 100644
--- a/modules/gdscript/gdscript_analyzer.h
+++ b/modules/gdscript/gdscript_analyzer.h
@@ -41,9 +41,22 @@
 class GDScriptAnalyzer {
 	GDScriptParser *parser = nullptr;
 
+	template <typename Fn>
+	class Finally {
+		Fn fn;
+
+	public:
+		Finally(Fn p_fn) :
+				fn(p_fn) {}
+		~Finally() {
+			fn();
+		}
+	};
+
 	const GDScriptParser::EnumNode *current_enum = nullptr;
 	GDScriptParser::LambdaNode *current_lambda = nullptr;
 	List<GDScriptParser::LambdaNode *> pending_body_resolution_lambdas;
+	HashMap<const GDScriptParser::ClassNode *, Ref<GDScriptParserRef>> external_class_parser_cache;
 	bool static_context = false;
 
 	// Tests for detecting invalid overloading of script members
@@ -132,6 +145,8 @@ class GDScriptAnalyzer {
 	void resolve_pending_lambda_bodies();
 	bool class_exists(const StringName &p_class) const;
 	void reduce_identifier_from_base_set_class(GDScriptParser::IdentifierNode *p_identifier, GDScriptParser::DataType p_identifier_datatype);
+	Ref<GDScriptParserRef> ensure_cached_parser_for_class(const GDScriptParser::ClassNode *p_class, const GDScriptParser::ClassNode *p_from_class, const String &p_context, const GDScriptParser::Node *p_source);
+	Ref<GDScript> get_depended_shallow_script(const String &p_path, Error &r_error);
 #ifdef DEBUG_ENABLED
 	void is_shadowing(GDScriptParser::IdentifierNode *p_identifier, const String &p_context, const bool p_in_local_scope);
 #endif