added 'is null' operator

rune-scape · Jun 19, 2023 · db97059 · db97059
1 parent b074f4f
commit db97059
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Showing 3 changed files with 32 additions and 3 deletions.
diff --git a/modules/gdscript/gdscript_analyzer.cpp b/modules/gdscript/gdscript_analyzer.cpp
@@ -4466,7 +4466,16 @@ void GDScriptAnalyzer::reduce_type_test(GDScriptParser::TypeTestNode *p_type_tes
 		p_type_test->is_constant = true;
 		p_type_test->reduced_value = false;
 
-		if (!is_type_compatible(test_type, operand_type)) {
+		if (test_type.kind == GDScriptParser::DataType::BUILTIN && test_type.builtin_type == Variant::NIL) {
+			const Variant &operand_reduced_value = p_type_test->operand->reduced_value;
+			if (operand_reduced_value.get_type() == Variant::NIL) {
+				p_type_test->reduced_value = true;
+			} else if (operand_reduced_value.get_type() == Variant::OBJECT && operand_reduced_value.is_null()) {
+				p_type_test->reduced_value = true;
+			} else {
+				p_type_test->reduced_value = false;
+			}
+		} else if (!is_type_compatible(test_type, operand_type)) {
 			push_error(vformat(R"(Expression is of type "%s" so it can't be of type "%s".)", operand_type.to_string(), test_type.to_string()), p_type_test->operand);
 		} else if (is_type_compatible(test_type, type_from_variant(p_type_test->operand->reduced_value, p_type_test->operand))) {
 			p_type_test->reduced_value = test_type.builtin_type != Variant::OBJECT || !p_type_test->operand->reduced_value.is_null();
@@ -4475,7 +4484,11 @@ void GDScriptAnalyzer::reduce_type_test(GDScriptParser::TypeTestNode *p_type_tes
 		return;
 	}
 
-	if (!is_type_compatible(test_type, operand_type) && !is_type_compatible(operand_type, test_type)) {
+	if (test_type.kind == GDScriptParser::DataType::BUILTIN && test_type.builtin_type == Variant::NIL) {
+		if (operand_type.kind == GDScriptParser::DataType::ENUM || (operand_type.kind == GDScriptParser::DataType::BUILTIN && operand_type.builtin_type != Variant::NIL && operand_type.builtin_type != Variant::OBJECT)) {
+			push_error(vformat(R"(Expression is of type "%s" so it can't be null.)", operand_type.to_string()), p_type_test->operand);
+		}
+	} else if (!is_type_compatible(test_type, operand_type) && !is_type_compatible(operand_type, test_type)) {
 		if (operand_type.is_hard_type()) {
 			push_error(vformat(R"(Expression is of type "%s" so it can't be of type "%s".)", operand_type.to_string(), test_type.to_string()), p_type_test->operand);
 		} else {

diff --git a/modules/gdscript/gdscript_byte_codegen.cpp b/modules/gdscript/gdscript_byte_codegen.cpp
@@ -624,6 +624,9 @@ void GDScriptByteCodeGenerator::write_type_test(const Address &p_target, const A
 				append(get_constant_pos(element_type.script_type) | (GDScriptFunction::ADDR_TYPE_CONSTANT << GDScriptFunction::ADDR_BITS));
 				append(element_type.builtin_type);
 				append(element_type.native_type);
+			} else if (p_type.builtin_type == Variant::NIL) {
+				GDScriptCodeGenerator::Address null_value_address(GDScriptCodeGenerator::Address::CONSTANT, add_or_get_constant(Variant()), p_type);
+				write_binary_operator(p_target, Variant::OP_EQUAL, p_source, null_value_address);
 			} else {
 				append_opcode(GDScriptFunction::OPCODE_TYPE_TEST_BUILTIN);
 				append(p_target);

diff --git a/modules/gdscript/gdscript_parser.cpp b/modules/gdscript/gdscript_parser.cpp
@@ -3317,7 +3317,20 @@ GDScriptParser::ExpressionNode *GDScriptParser::parse_type_test(ExpressionNode *
 		type_test->is_not = true;
 	}
 
-	type_test->test_type = parse_type();
+	if (check(GDScriptTokenizer::Token::LITERAL) && current.literal == Variant()) {
+		IdentifierNode *nil_identifier = alloc_node<IdentifierNode>();
+		nil_identifier->name = SNAME("Nil");
+		complete_extents(nil_identifier);
+
+		TypeNode *type = alloc_node<TypeNode>();
+		type->type_chain.push_back(nil_identifier);
+		complete_extents(type);
+
+		type_test->test_type = type;
+	} else {
+		type_test->test_type = parse_type();
+	}
+
 	complete_extents(type_test);
 
 	if (type_test->test_type == nullptr) {