Implement iterator variable typing in GDScript

3 files changed, 57 insertions, 4 deletions

diff --git a/modules/gdscript/gdscript_analyzer.cpp b/modules/gdscript/gdscript_analyzer.cpp
index 6b7403d854..f090e7db25 100644
--- a/modules/gdscript/gdscript_analyzer.cpp
+++ b/modules/gdscript/gdscript_analyzer.cpp
@@ -1089,12 +1089,28 @@ void GDScriptAnalyzer::resolve_for(GDScriptParser::ForNode *p_for) {
 		}
 	}
 
-	if (!list_resolved) {
+	GDScriptParser::DataType variable_type;
+	if (list_resolved) {
+		variable_type.type_source = GDScriptParser::DataType::ANNOTATED_INFERRED;
+		variable_type.kind = GDScriptParser::DataType::BUILTIN;
+		variable_type.builtin_type = Variant::INT; // Can this ever be a float or something else?
+		p_for->variable->set_datatype(variable_type);
+	} else {
 		resolve_node(p_for->list);
+		if (p_for->list->datatype.has_container_element_type()) {
+			variable_type = p_for->list->datatype.get_container_element_type();
+			variable_type.type_source = GDScriptParser::DataType::ANNOTATED_INFERRED;
+		} else if (p_for->list->datatype.is_typed_container_type()) {
+			variable_type = p_for->list->datatype.get_typed_container_type();
+			variable_type.type_source = GDScriptParser::DataType::ANNOTATED_INFERRED;
+		} else {
+			// Last resort
+			// TODO: Must other cases be handled? Must we mark as unsafe?
+			variable_type.type_source = GDScriptParser::DataType::UNDETECTED;
+			variable_type.kind = GDScriptParser::DataType::VARIANT;
+		}
 	}
-
-	// TODO: If list is a typed array, the variable should be an element.
-	// Also applicable for constant range() (so variable is int or float).
+	p_for->variable->set_datatype(variable_type);
 
 	resolve_suite(p_for->loop);
 	p_for->set_datatype(p_for->loop->get_datatype());
diff --git a/modules/gdscript/gdscript_parser.cpp b/modules/gdscript/gdscript_parser.cpp
index d21caf4389..1cbb4861bc 100644
--- a/modules/gdscript/gdscript_parser.cpp
+++ b/modules/gdscript/gdscript_parser.cpp
@@ -3540,6 +3540,39 @@ String GDScriptParser::DataType::to_string() const {
 	ERR_FAIL_V_MSG("<unresolved type", "Kind set outside the enum range.");
 }
 
+static Variant::Type _variant_type_to_typed_array_element_type(Variant::Type p_type) {
+	switch (p_type) {
+		case Variant::PACKED_BYTE_ARRAY:
+		case Variant::PACKED_INT32_ARRAY:
+		case Variant::PACKED_INT64_ARRAY:
+			return Variant::INT;
+		case Variant::PACKED_FLOAT32_ARRAY:
+		case Variant::PACKED_FLOAT64_ARRAY:
+			return Variant::FLOAT;
+		case Variant::PACKED_STRING_ARRAY:
+			return Variant::STRING;
+		case Variant::PACKED_VECTOR2_ARRAY:
+			return Variant::VECTOR2;
+		case Variant::PACKED_VECTOR3_ARRAY:
+			return Variant::VECTOR3;
+		case Variant::PACKED_COLOR_ARRAY:
+			return Variant::COLOR;
+		default:
+			return Variant::NIL;
+	}
+}
+
+bool GDScriptParser::DataType::is_typed_container_type() const {
+	return kind == GDScriptParser::DataType::BUILTIN && _variant_type_to_typed_array_element_type(builtin_type) != Variant::NIL;
+}
+
+GDScriptParser::DataType GDScriptParser::DataType::get_typed_container_type() const {
+	GDScriptParser::DataType type;
+	type.kind = GDScriptParser::DataType::BUILTIN;
+	type.builtin_type = _variant_type_to_typed_array_element_type(builtin_type);
+	return type;
+}
+
 /*---------- PRETTY PRINT FOR DEBUG ----------*/
 
 #ifdef DEBUG_ENABLED
diff --git a/modules/gdscript/gdscript_parser.h b/modules/gdscript/gdscript_parser.h
index 0bce8d7ddd..ed5300eb59 100644
--- a/modules/gdscript/gdscript_parser.h
+++ b/modules/gdscript/gdscript_parser.h
@@ -161,6 +161,10 @@ public:
 			container_element_type = nullptr;
 		}
 
+		bool is_typed_container_type() const;
+
+		GDScriptParser::DataType get_typed_container_type() const;
+
 		bool operator==(const DataType &p_other) const {
 			if (type_source == UNDETECTED || p_other.type_source == UNDETECTED) {
 				return true; // Can be consireded equal for parsing purposes.