GDScript: Add error when exporting node in non [Node]-derived classes

modules/gdscript/doc_classes/@GDScript.xml

@@ -285,11 +285,36 @@
 			<description>
 				Mark the following property as exported (editable in the Inspector dock and saved to disk). To control the type of the exported property, use the type hint notation.
 				[codeblock]
+				extends Node
+
+				enum Direction {LEFT, RIGHT, UP, DOWN}
+
+				# Built-in types.
 				@export var string = ""
 				@export var int_number = 5
 				@export var float_number: float = 5
+
+				# Enums.
+				@export var type: Variant.Type
+				@export var format: Image.Format
+				@export var direction: Direction
+
+				# Resources.
 				@export var image: Image
+				@export var custom_resource: CustomResource
+
+				# Nodes.
+				@export var node: Node
+				@export var custom_node: CustomNode
+
+				# Typed arrays.
+				@export var int_array: Array[int]
+				@export var direction_array: Array[Direction]
+				@export var image_array: Array[Image]
+				@export var node_array: Array[Node]
 				[/codeblock]
+				[b]Note:[/b] Custom resources and nodes must be registered as global classes using [code]class_name[/code].
+				[b]Note:[/b] Node export is only supported in [Node]-derived classes and has a number of other limitations.
 			</description>
 		</annotation>
 		<annotation name="@export_category">

modules/gdscript/gdscript_analyzer.cpp

@@ -910,7 +910,7 @@ void GDScriptAnalyzer::resolve_class_member(GDScriptParser::ClassNode *p_class,
 			for (GDScriptParser::AnnotationNode *&E : member_node->annotations) {
 				if (E->name == SNAME("@warning_ignore")) {
 					resolve_annotation(E);
-					E->apply(parser, member.variable);
+					E->apply(parser, member.variable, p_class);
 				}
 			}
 			for (GDScriptWarning::Code ignored_warning : member_node->ignored_warnings) {
@@ -933,7 +933,7 @@ void GDScriptAnalyzer::resolve_class_member(GDScriptParser::ClassNode *p_class,
 				for (GDScriptParser::AnnotationNode *&E : member.variable->annotations) {
 					if (E->name != SNAME("@warning_ignore")) {
 						resolve_annotation(E);
-						E->apply(parser, member.variable);
+						E->apply(parser, member.variable, p_class);
 					}
 				}
 
@@ -985,7 +985,7 @@ void GDScriptAnalyzer::resolve_class_member(GDScriptParser::ClassNode *p_class,
 				// Apply annotations.
 				for (GDScriptParser::AnnotationNode *&E : member.constant->annotations) {
 					resolve_annotation(E);
-					E->apply(parser, member.constant);
+					E->apply(parser, member.constant, p_class);
 				}
 			} break;
 			case GDScriptParser::ClassNode::Member::SIGNAL: {
@@ -1015,7 +1015,7 @@ void GDScriptAnalyzer::resolve_class_member(GDScriptParser::ClassNode *p_class,
 				// Apply annotations.
 				for (GDScriptParser::AnnotationNode *&E : member.signal->annotations) {
 					resolve_annotation(E);
-					E->apply(parser, member.signal);
+					E->apply(parser, member.signal, p_class);
 				}
 			} break;
 			case GDScriptParser::ClassNode::Member::ENUM: {
@@ -1063,13 +1063,13 @@ void GDScriptAnalyzer::resolve_class_member(GDScriptParser::ClassNode *p_class,
 				// Apply annotations.
 				for (GDScriptParser::AnnotationNode *&E : member.m_enum->annotations) {
 					resolve_annotation(E);
-					E->apply(parser, member.m_enum);
+					E->apply(parser, member.m_enum, p_class);
 				}
 			} break;
 			case GDScriptParser::ClassNode::Member::FUNCTION:
 				for (GDScriptParser::AnnotationNode *&E : member.function->annotations) {
 					resolve_annotation(E);
-					E->apply(parser, member.function);
+					E->apply(parser, member.function, p_class);
 				}
 				resolve_function_signature(member.function, p_source);
 				break;
@@ -1279,7 +1279,7 @@ void GDScriptAnalyzer::resolve_class_body(GDScriptParser::ClassNode *p_class, co
 			// Apply annotations.
 			for (GDScriptParser::AnnotationNode *&E : member.function->annotations) {
 				resolve_annotation(E);
-				E->apply(parser, member.function);
+				E->apply(parser, member.function, p_class);
 			}
 			resolve_function_body(member.function);
 		} else if (member.type == GDScriptParser::ClassNode::Member::VARIABLE && member.variable->property != GDScriptParser::VariableNode::PROP_NONE) {
@@ -1301,7 +1301,7 @@ void GDScriptAnalyzer::resolve_class_body(GDScriptParser::ClassNode *p_class, co
 		} else if (member.type == GDScriptParser::ClassNode::Member::GROUP) {
 			// Apply annotation (`@export_{category,group,subgroup}`).
 			resolve_annotation(member.annotation);
-			member.annotation->apply(parser, nullptr);
+			member.annotation->apply(parser, nullptr, p_class);
 		}
 	}
 
@@ -1837,7 +1837,7 @@ void GDScriptAnalyzer::resolve_suite(GDScriptParser::SuiteNode *p_suite) {
 		// Apply annotations.
 		for (GDScriptParser::AnnotationNode *&E : stmt->annotations) {
 			resolve_annotation(E);
-			E->apply(parser, stmt);
+			E->apply(parser, stmt, nullptr);
 		}
 
 #ifdef DEBUG_ENABLED
@@ -5544,7 +5544,7 @@ Error GDScriptAnalyzer::analyze() {
 	// Apply annotations.
 	for (GDScriptParser::AnnotationNode *&E : parser->head->annotations) {
 		resolve_annotation(E);
-		E->apply(parser, parser->head);
+		E->apply(parser, parser->head, nullptr);
 	}
 
 	resolve_interface();

modules/gdscript/gdscript_parser.cpp

@@ -519,7 +519,7 @@ void GDScriptParser::parse_program() {
 				if (annotation->applies_to(AnnotationInfo::SCRIPT)) {
 					// `@icon` needs to be applied in the parser. See GH-72444.
 					if (annotation->name == SNAME("@icon")) {
-						annotation->apply(this, head);
+						annotation->apply(this, head, nullptr);
 					} else {
 						head->annotations.push_back(annotation);
 					}
@@ -3795,12 +3795,12 @@ const GDScriptParser::SuiteNode::Local &GDScriptParser::SuiteNode::get_local(con
 	return empty;
 }
 
-bool GDScriptParser::AnnotationNode::apply(GDScriptParser *p_this, Node *p_target) {
+bool GDScriptParser::AnnotationNode::apply(GDScriptParser *p_this, Node *p_target, ClassNode *p_class) {
 	if (is_applied) {
 		return true;
 	}
 	is_applied = true;
-	return (p_this->*(p_this->valid_annotations[name].apply))(this, p_target);
+	return (p_this->*(p_this->valid_annotations[name].apply))(this, p_target, p_class);
 }
 
 bool GDScriptParser::AnnotationNode::applies_to(uint32_t p_target_kinds) const {
@@ -3846,7 +3846,7 @@ bool GDScriptParser::validate_annotation_arguments(AnnotationNode *p_annotation)
 	return true;
 }
 
-bool GDScriptParser::tool_annotation(const AnnotationNode *p_annotation, Node *p_node) {
+bool GDScriptParser::tool_annotation(const AnnotationNode *p_annotation, Node *p_target, ClassNode *p_class) {
 #ifdef DEBUG_ENABLED
 	if (this->_is_tool) {
 		push_error(R"("@tool" annotation can only be used once.)", p_annotation);
@@ -3857,15 +3857,15 @@ bool GDScriptParser::tool_annotation(const AnnotationNode *p_annotation, Node *p
 	return true;
 }
 
-bool GDScriptParser::icon_annotation(const AnnotationNode *p_annotation, Node *p_node) {
-	ERR_FAIL_COND_V_MSG(p_node->type != Node::CLASS, false, R"("@icon" annotation can only be applied to classes.)");
+bool GDScriptParser::icon_annotation(const AnnotationNode *p_annotation, Node *p_target, ClassNode *p_class) {
+	ERR_FAIL_COND_V_MSG(p_target->type != Node::CLASS, false, R"("@icon" annotation can only be applied to classes.)");
 	ERR_FAIL_COND_V(p_annotation->resolved_arguments.is_empty(), false);
 
-	ClassNode *p_class = static_cast<ClassNode *>(p_node);
+	ClassNode *class_node = static_cast<ClassNode *>(p_target);
 	String path = p_annotation->resolved_arguments[0];
 
 #ifdef DEBUG_ENABLED
-	if (!p_class->icon_path.is_empty()) {
+	if (!class_node->icon_path.is_empty()) {
 		push_error(R"("@icon" annotation can only be used once.)", p_annotation);
 		return false;
 	}
@@ -3875,27 +3875,27 @@ bool GDScriptParser::icon_annotation(const AnnotationNode *p_annotation, Node *p
 	}
 #endif // DEBUG_ENABLED
 
-	p_class->icon_path = path;
+	class_node->icon_path = path;
 
 	if (path.is_empty() || path.is_absolute_path()) {
-		p_class->simplified_icon_path = path.simplify_path();
+		class_node->simplified_icon_path = path.simplify_path();
 	} else if (path.is_relative_path()) {
-		p_class->simplified_icon_path = script_path.get_base_dir().path_join(path).simplify_path();
+		class_node->simplified_icon_path = script_path.get_base_dir().path_join(path).simplify_path();
 	} else {
-		p_class->simplified_icon_path = path;
+		class_node->simplified_icon_path = path;
 	}
 
 	return true;
 }
 
-bool GDScriptParser::onready_annotation(const AnnotationNode *p_annotation, Node *p_node) {
-	ERR_FAIL_COND_V_MSG(p_node->type != Node::VARIABLE, false, R"("@onready" annotation can only be applied to class variables.)");
+bool GDScriptParser::onready_annotation(const AnnotationNode *p_annotation, Node *p_target, ClassNode *p_class) {
+	ERR_FAIL_COND_V_MSG(p_target->type != Node::VARIABLE, false, R"("@onready" annotation can only be applied to class variables.)");
 
 	if (current_class && !ClassDB::is_parent_class(current_class->get_datatype().native_type, SNAME("Node"))) {
 		push_error(R"("@onready" can only be used in classes that inherit "Node".)", p_annotation);
 	}
 
-	VariableNode *variable = static_cast<VariableNode *>(p_node);
+	VariableNode *variable = static_cast<VariableNode *>(p_target);
 	if (variable->is_static) {
 		push_error(R"("@onready" annotation cannot be applied to a static variable.)", p_annotation);
 		return false;
@@ -3910,10 +3910,11 @@ bool GDScriptParser::onready_annotation(const AnnotationNode *p_annotation, Node
 }
 
 template <PropertyHint t_hint, Variant::Type t_type>
-bool GDScriptParser::export_annotations(const AnnotationNode *p_annotation, Node *p_node) {
-	ERR_FAIL_COND_V_MSG(p_node->type != Node::VARIABLE, false, vformat(R"("%s" annotation can only be applied to variables.)", p_annotation->name));
+bool GDScriptParser::export_annotations(const AnnotationNode *p_annotation, Node *p_target, ClassNode *p_class) {
+	ERR_FAIL_COND_V_MSG(p_target->type != Node::VARIABLE, false, vformat(R"("%s" annotation can only be applied to variables.)", p_annotation->name));
+	ERR_FAIL_NULL_V(p_class, false);
 
-	VariableNode *variable = static_cast<VariableNode *>(p_node);
+	VariableNode *variable = static_cast<VariableNode *>(p_target);
 	if (variable->is_static) {
 		push_error(vformat(R"(Annotation "%s" cannot be applied to a static variable.)", p_annotation->name), p_annotation);
 		return false;
@@ -4128,7 +4129,12 @@ bool GDScriptParser::export_annotations(const AnnotationNode *p_annotation, Node
 			} break;
 			default:
 				push_error(R"(Export type can only be built-in, a resource, a node, or an enum.)", variable);
-				break;
+				return false;
+		}
+
+		if (variable->export_info.hint == PROPERTY_HINT_NODE_TYPE && !ClassDB::is_parent_class(p_class->base_type.native_type, SNAME("Node"))) {
+			push_error(vformat(R"(Node export is only supported in Node-derived classes, but the current class inherits "%s".)", p_class->base_type.to_string()), variable);
+			return false;
 		}
 
 		if (is_array) {
@@ -4173,7 +4179,7 @@ bool GDScriptParser::export_annotations(const AnnotationNode *p_annotation, Node
 }
 
 template <PropertyUsageFlags t_usage>
-bool GDScriptParser::export_group_annotations(const AnnotationNode *p_annotation, Node *p_node) {
+bool GDScriptParser::export_group_annotations(const AnnotationNode *p_annotation, Node *p_target, ClassNode *p_class) {
 	AnnotationNode *annotation = const_cast<AnnotationNode *>(p_annotation);
 
 	if (annotation->resolved_arguments.is_empty()) {
@@ -4205,7 +4211,7 @@ bool GDScriptParser::export_group_annotations(const AnnotationNode *p_annotation
 	return true;
 }
 
-bool GDScriptParser::warning_annotations(const AnnotationNode *p_annotation, Node *p_node) {
+bool GDScriptParser::warning_annotations(const AnnotationNode *p_annotation, Node *p_target, ClassNode *p_class) {
 #ifdef DEBUG_ENABLED
 	bool has_error = false;
 	for (const Variant &warning_name : p_annotation->resolved_arguments) {
@@ -4214,7 +4220,7 @@ bool GDScriptParser::warning_annotations(const AnnotationNode *p_annotation, Nod
 			push_error(vformat(R"(Invalid warning name: "%s".)", warning_name), p_annotation);
 			has_error = true;
 		} else {
-			p_node->ignored_warnings.push_back(warning);
+			p_target->ignored_warnings.push_back(warning);
 		}
 	}
 
@@ -4226,10 +4232,10 @@ bool GDScriptParser::warning_annotations(const AnnotationNode *p_annotation, Nod
 #endif // DEBUG_ENABLED
 }
 
-bool GDScriptParser::rpc_annotation(const AnnotationNode *p_annotation, Node *p_node) {
-	ERR_FAIL_COND_V_MSG(p_node->type != Node::FUNCTION, false, vformat(R"("%s" annotation can only be applied to functions.)", p_annotation->name));
+bool GDScriptParser::rpc_annotation(const AnnotationNode *p_annotation, Node *p_target, ClassNode *p_class) {
+	ERR_FAIL_COND_V_MSG(p_target->type != Node::FUNCTION, false, vformat(R"("%s" annotation can only be applied to functions.)", p_annotation->name));
 
-	FunctionNode *function = static_cast<FunctionNode *>(p_node);
+	FunctionNode *function = static_cast<FunctionNode *>(p_target);
 	if (function->rpc_config.get_type() != Variant::NIL) {
 		push_error(R"(RPC annotations can only be used once per function.)", p_annotation);
 		return false;
@@ -4287,14 +4293,14 @@ bool GDScriptParser::rpc_annotation(const AnnotationNode *p_annotation, Node *p_
 	return true;
 }
 
-bool GDScriptParser::static_unload_annotation(const AnnotationNode *p_annotation, Node *p_target) {
+bool GDScriptParser::static_unload_annotation(const AnnotationNode *p_annotation, Node *p_target, ClassNode *p_class) {
 	ERR_FAIL_COND_V_MSG(p_target->type != Node::CLASS, false, vformat(R"("%s" annotation can only be applied to classes.)", p_annotation->name));
-	ClassNode *p_class = static_cast<ClassNode *>(p_target);
-	if (p_class->annotated_static_unload) {
+	ClassNode *class_node = static_cast<ClassNode *>(p_target);
+	if (class_node->annotated_static_unload) {
 		push_error(vformat(R"("%s" annotation can only be used once per script.)", p_annotation->name), p_annotation);
 		return false;
 	}
-	p_class->annotated_static_unload = true;
+	class_node->annotated_static_unload = true;
 	return true;
 }
 

modules/gdscript/gdscript_parser.h

@@ -363,7 +363,7 @@ public:
 		bool is_resolved = false;
 		bool is_applied = false;
 
-		bool apply(GDScriptParser *p_this, Node *p_target);
+		bool apply(GDScriptParser *p_this, Node *p_target, ClassNode *p_class);
 		bool applies_to(uint32_t p_target_kinds) const;
 
 		AnnotationNode() {
@@ -1340,7 +1340,7 @@ private:
 	bool in_lambda = false;
 	bool lambda_ended = false; // Marker for when a lambda ends, to apply an end of statement if needed.
 
-	typedef bool (GDScriptParser::*AnnotationAction)(const AnnotationNode *p_annotation, Node *p_target);
+	typedef bool (GDScriptParser::*AnnotationAction)(const AnnotationNode *p_annotation, Node *p_target, ClassNode *p_class);
 	struct AnnotationInfo {
 		enum TargetKind {
 			NONE = 0,
@@ -1461,16 +1461,16 @@ private:
 	bool register_annotation(const MethodInfo &p_info, uint32_t p_target_kinds, AnnotationAction p_apply, const Vector<Variant> &p_default_arguments = Vector<Variant>(), bool p_is_vararg = false);
 	bool validate_annotation_arguments(AnnotationNode *p_annotation);
 	void clear_unused_annotations();
-	bool tool_annotation(const AnnotationNode *p_annotation, Node *p_target);
-	bool icon_annotation(const AnnotationNode *p_annotation, Node *p_target);
-	bool onready_annotation(const AnnotationNode *p_annotation, Node *p_target);
+	bool tool_annotation(const AnnotationNode *p_annotation, Node *p_target, ClassNode *p_class);
+	bool icon_annotation(const AnnotationNode *p_annotation, Node *p_target, ClassNode *p_class);
+	bool onready_annotation(const AnnotationNode *p_annotation, Node *p_target, ClassNode *p_class);
 	template <PropertyHint t_hint, Variant::Type t_type>
-	bool export_annotations(const AnnotationNode *p_annotation, Node *p_target);
+	bool export_annotations(const AnnotationNode *p_annotation, Node *p_target, ClassNode *p_class);
 	template <PropertyUsageFlags t_usage>
-	bool export_group_annotations(const AnnotationNode *p_annotation, Node *p_target);
-	bool warning_annotations(const AnnotationNode *p_annotation, Node *p_target);
-	bool rpc_annotation(const AnnotationNode *p_annotation, Node *p_target);
-	bool static_unload_annotation(const AnnotationNode *p_annotation, Node *p_target);
+	bool export_group_annotations(const AnnotationNode *p_annotation, Node *p_target, ClassNode *p_class);
+	bool warning_annotations(const AnnotationNode *p_annotation, Node *p_target, ClassNode *p_class);
+	bool rpc_annotation(const AnnotationNode *p_annotation, Node *p_target, ClassNode *p_class);
+	bool static_unload_annotation(const AnnotationNode *p_annotation, Node *p_target, ClassNode *p_class);
 	// Statements.
 	Node *parse_statement();
 	VariableNode *parse_variable(bool p_is_static);

modules/gdscript/tests/scripts/analyzer/errors/export_node_in_non_node_derived_class_1.gd

@@ -0,0 +1,8 @@
+# GH-82809
+
+extends Resource
+
+@export var node: Node
+
+func test():
+	pass

modules/gdscript/tests/scripts/analyzer/errors/export_node_in_non_node_derived_class_1.out

@@ -0,0 +1,2 @@
+GDTEST_ANALYZER_ERROR
+Node export is only supported in Node-derived classes, but the current class inherits "Resource".

modules/gdscript/tests/scripts/analyzer/errors/export_node_in_non_node_derived_class_2.gd

@@ -0,0 +1,9 @@
+# GH-82809
+
+extends Node
+
+class Inner:
+	@export var node: Node
+
+func test():
+	pass

modules/gdscript/tests/scripts/analyzer/errors/export_node_in_non_node_derived_class_2.out

@@ -0,0 +1,2 @@
+GDTEST_ANALYZER_ERROR
+Node export is only supported in Node-derived classes, but the current class inherits "RefCounted".

modules/gdscript/tests/scripts/analyzer/errors/export_node_in_non_node_derived_class_3.gd

@@ -0,0 +1,8 @@
+# GH-82809
+
+extends Resource
+
+@export var node_array: Array[Node]
+
+func test():
+	pass

modules/gdscript/tests/scripts/analyzer/errors/export_node_in_non_node_derived_class_3.out

@@ -0,0 +1,2 @@
+GDTEST_ANALYZER_ERROR
+Node export is only supported in Node-derived classes, but the current class inherits "Resource".

modules/gdscript/tests/scripts/parser/features/export_variable.gd

@@ -1,3 +1,5 @@
+extends Node
+
 @export var example = 99
 @export_range(0, 100) var example_range = 100
 @export_range(0, 100, 1) var example_range_step = 101
@@ -6,7 +8,8 @@
 @export var color: Color
 @export_color_no_alpha var color_no_alpha: Color
 @export_node_path("Sprite2D", "Sprite3D", "Control", "Node") var nodepath := ^"hello"
-
+@export var node: Node
+@export var node_array: Array[Node]
 
 func test():
 	print(example)
@@ -16,3 +19,5 @@ func test():
 	print(color)
 	print(color_no_alpha)
 	print(nodepath)
+	print(node)
+	print(var_to_str(node_array))

modules/gdscript/tests/scripts/parser/features/export_variable.out

@@ -6,3 +6,5 @@ GDTEST_OK
 (0, 0, 0, 1)
 (0, 0, 0, 1)
 hello
+<null>
+Array[Node]([])