From cd487201c63c5b99a47971b7bd1b55b483b44ceb Mon Sep 17 00:00:00 2001
From: Thakee Nathees <thakeenathees@gmail.com>
Date: Mon, 9 Mar 2020 04:54:12 +0530
Subject: [PATCH] export var type reduce() implemented

---
 modules/gdscript/gdscript_parser.cpp | 35 ++++++++++++++++++++++++++++
 modules/gdscript/gdscript_parser.h   |  1 +
 2 files changed, 36 insertions(+)

diff --git a/modules/gdscript/gdscript_parser.cpp b/modules/gdscript/gdscript_parser.cpp
index 8d34ce5c709..f46f624ee5e 100644
--- a/modules/gdscript/gdscript_parser.cpp
+++ b/modules/gdscript/gdscript_parser.cpp
@@ -2022,6 +2022,38 @@ GDScriptParser::Node *GDScriptParser::_parse_and_reduce_expression(Node *p_paren
 	return expr;
 }
 
+bool GDScriptParser::_reduce_export_var_type(Variant &p_value, int p_line) {
+
+	if (p_value.get_type() == Variant::ARRAY) {
+		Array arr = p_value;
+		for (int i = 0; i < arr.size(); i++) {
+			if (!_reduce_export_var_type(arr[i], p_line)) return false;
+		}
+		return true;
+	}
+
+	if (p_value.get_type() == Variant::DICTIONARY) {
+		Dictionary dict = p_value;
+		for (int i = 0; i < dict.size(); i++) {
+			Variant value = dict.get_value_at_index(i);
+			if (!_reduce_export_var_type(value, p_line)) return false;
+		}
+		return true;
+	}
+
+	// validate type
+	DataType type = _type_from_variant(p_value);
+	if (type.kind == DataType::BUILTIN) {
+		return true;
+	} else if (type.kind == DataType::NATIVE) {
+		if (ClassDB::is_parent_class(type.native_type, "Resource")) {
+			return true;
+		}
+	}
+	_set_error("Invalid export type. Only built-in and native resource types can be exported.", p_line);
+	return false;
+}
+
 bool GDScriptParser::_recover_from_completion() {
 
 	if (!completion_found) {
@@ -4863,6 +4895,9 @@ void GDScriptParser::_parse_class(ClassNode *p_class) {
 							_set_error("Can't accept a null constant expression for inferring export type.");
 							return;
 						}
+
+						if (!_reduce_export_var_type(cn->value, member.line)) return;
+
 						member._export.type = cn->value.get_type();
 						member._export.usage |= PROPERTY_USAGE_SCRIPT_VARIABLE;
 						if (cn->value.get_type() == Variant::OBJECT) {
diff --git a/modules/gdscript/gdscript_parser.h b/modules/gdscript/gdscript_parser.h
index eca5f83f7a8..f2543524233 100644
--- a/modules/gdscript/gdscript_parser.h
+++ b/modules/gdscript/gdscript_parser.h
@@ -613,6 +613,7 @@ private:
 	Node *_parse_expression(Node *p_parent, bool p_static, bool p_allow_assign = false, bool p_parsing_constant = false);
 	Node *_reduce_expression(Node *p_node, bool p_to_const = false);
 	Node *_parse_and_reduce_expression(Node *p_parent, bool p_static, bool p_reduce_const = false, bool p_allow_assign = false);
+	bool _reduce_export_var_type(Variant &p_value, int p_line = 0);
 
 	PatternNode *_parse_pattern(bool p_static);
 	void _parse_pattern_block(BlockNode *p_block, Vector<PatternBranchNode *> &p_branches, bool p_static);