GDScript: Fix typing of iterator in for loop

23 files changed, 202 insertions, 12 deletions

diff --git a/modules/gdscript/gdscript_analyzer.cpp b/modules/gdscript/gdscript_analyzer.cpp
index 0c858a36e7..21c65cfb30 100644
--- a/modules/gdscript/gdscript_analyzer.cpp
+++ b/modules/gdscript/gdscript_analyzer.cpp
@@ -1722,21 +1722,52 @@ void GDScriptAnalyzer::resolve_for(GDScriptParser::ForNode *p_for) {
 	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);
+		variable_type.builtin_type = Variant::INT;
 	} else if (p_for->list) {
 		resolve_node(p_for->list, false);
-		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;
+		GDScriptParser::DataType list_type = p_for->list->get_datatype();
+		if (!list_type.is_hard_type()) {
+			mark_node_unsafe(p_for->list);
+		}
+		if (list_type.is_variant()) {
+			variable_type.kind = GDScriptParser::DataType::VARIANT;
+			mark_node_unsafe(p_for->list);
+		} else if (list_type.has_container_element_type()) {
+			variable_type = list_type.get_container_element_type();
+			variable_type.type_source = list_type.type_source;
+		} else if (list_type.is_typed_container_type()) {
+			variable_type = list_type.get_typed_container_type();
+			variable_type.type_source = list_type.type_source;
+		} else if (list_type.builtin_type == Variant::INT || list_type.builtin_type == Variant::FLOAT || list_type.builtin_type == Variant::STRING) {
+			variable_type.type_source = list_type.type_source;
+			variable_type.kind = GDScriptParser::DataType::BUILTIN;
+			variable_type.builtin_type = list_type.builtin_type;
+		} else if (list_type.builtin_type == Variant::VECTOR2I || list_type.builtin_type == Variant::VECTOR3I) {
+			variable_type.type_source = list_type.type_source;
+			variable_type.kind = GDScriptParser::DataType::BUILTIN;
+			variable_type.builtin_type = Variant::INT;
+		} else if (list_type.builtin_type == Variant::VECTOR2 || list_type.builtin_type == Variant::VECTOR3) {
+			variable_type.type_source = list_type.type_source;
+			variable_type.kind = GDScriptParser::DataType::BUILTIN;
+			variable_type.builtin_type = Variant::FLOAT;
+		} else if (list_type.builtin_type == Variant::OBJECT) {
+			GDScriptParser::DataType return_type;
+			List<GDScriptParser::DataType> par_types;
+			int default_arg_count = 0;
+			bool is_static = false;
+			bool is_vararg = false;
+			if (get_function_signature(p_for->list, false, list_type, CoreStringNames::get_singleton()->_iter_get, return_type, par_types, default_arg_count, is_static, is_vararg)) {
+				variable_type = return_type;
+				variable_type.type_source = list_type.type_source;
+			} else if (!list_type.is_hard_type()) {
+				variable_type.kind = GDScriptParser::DataType::VARIANT;
+			} else {
+				push_error(vformat(R"(Unable to iterate on object of type "%s".)", list_type.to_string()), p_for->list);
+			}
+		} else if (list_type.builtin_type == Variant::ARRAY || list_type.builtin_type == Variant::DICTIONARY || !list_type.is_hard_type()) {
 			variable_type.kind = GDScriptParser::DataType::VARIANT;
+		} else {
+			push_error(vformat(R"(Unable to iterate on value of type "%s".)", list_type.to_string()), p_for->list);
 		}
 	}
 	if (p_for->variable) {
diff --git a/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_constant_float.gd b/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_constant_float.gd
new file mode 100644
index 0000000000..cf56a0a933
--- /dev/null
+++ b/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_constant_float.gd
@@ -0,0 +1,6 @@
+const constant_float = 1.0
+
+func test():
+	for x in constant_float:
+		if x is String:
+			pass
diff --git a/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_constant_float.out b/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_constant_float.out
new file mode 100644
index 0000000000..e309831b3e
--- /dev/null
+++ b/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_constant_float.out
@@ -0,0 +1,2 @@
+GDTEST_ANALYZER_ERROR
+Expression is of type "float" so it can't be of type "String".
diff --git a/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_constant_int.gd b/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_constant_int.gd
new file mode 100644
index 0000000000..5ee8ac19e1
--- /dev/null
+++ b/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_constant_int.gd
@@ -0,0 +1,6 @@
+const constant_int = 1
+
+func test():
+	for x in constant_int:
+		if x is String:
+			pass
diff --git a/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_constant_int.out b/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_constant_int.out
new file mode 100644
index 0000000000..54c190cf8a
--- /dev/null
+++ b/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_constant_int.out
@@ -0,0 +1,2 @@
+GDTEST_ANALYZER_ERROR
+Expression is of type "int" so it can't be of type "String".
diff --git a/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_enum_value.gd b/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_enum_value.gd
new file mode 100644
index 0000000000..b3db4f3b49
--- /dev/null
+++ b/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_enum_value.gd
@@ -0,0 +1,6 @@
+enum { enum_value = 1 }
+
+func test():
+	for x in enum_value:
+		if x is String:
+			pass
diff --git a/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_enum_value.out b/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_enum_value.out
new file mode 100644
index 0000000000..54c190cf8a
--- /dev/null
+++ b/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_enum_value.out
@@ -0,0 +1,2 @@
+GDTEST_ANALYZER_ERROR
+Expression is of type "int" so it can't be of type "String".
diff --git a/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_hard_float.gd b/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_hard_float.gd
new file mode 100644
index 0000000000..87c54f7402
--- /dev/null
+++ b/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_hard_float.gd
@@ -0,0 +1,6 @@
+func test():
+	var hard_float := 1.0
+
+	for x in hard_float:
+		if x is String:
+			pass
diff --git a/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_hard_float.out b/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_hard_float.out
new file mode 100644
index 0000000000..e309831b3e
--- /dev/null
+++ b/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_hard_float.out
@@ -0,0 +1,2 @@
+GDTEST_ANALYZER_ERROR
+Expression is of type "float" so it can't be of type "String".
diff --git a/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_hard_int.gd b/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_hard_int.gd
new file mode 100644
index 0000000000..2a43f5a930
--- /dev/null
+++ b/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_hard_int.gd
@@ -0,0 +1,6 @@
+func test():
+	var hard_int := 1
+
+	for x in hard_int:
+		if x is String:
+			pass
diff --git a/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_hard_int.out b/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_hard_int.out
new file mode 100644
index 0000000000..54c190cf8a
--- /dev/null
+++ b/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_hard_int.out
@@ -0,0 +1,2 @@
+GDTEST_ANALYZER_ERROR
+Expression is of type "int" so it can't be of type "String".
diff --git a/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_hard_iterator.gd b/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_hard_iterator.gd
new file mode 100644
index 0000000000..c3920d35b3
--- /dev/null
+++ b/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_hard_iterator.gd
@@ -0,0 +1,14 @@
+class Iterator:
+	func _iter_init(_count):
+		return true
+	func _iter_next(_count):
+		return false
+	func _iter_get(_count) -> StringName:
+		return &'custom'
+
+func test():
+	var hard_iterator := Iterator.new()
+
+	for x in hard_iterator:
+		if x is int:
+			pass
diff --git a/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_hard_iterator.out b/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_hard_iterator.out
new file mode 100644
index 0000000000..a48591a3b4
--- /dev/null
+++ b/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_hard_iterator.out
@@ -0,0 +1,2 @@
+GDTEST_ANALYZER_ERROR
+Expression is of type "StringName" so it can't be of type "int".
diff --git a/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_hard_string.gd b/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_hard_string.gd
new file mode 100644
index 0000000000..b36d87aabe
--- /dev/null
+++ b/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_hard_string.gd
@@ -0,0 +1,6 @@
+func test():
+	var hard_string := 'a'
+
+	for x in hard_string:
+		if x is int:
+			pass
diff --git a/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_hard_string.out b/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_hard_string.out
new file mode 100644
index 0000000000..92c5ebc599
--- /dev/null
+++ b/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_hard_string.out
@@ -0,0 +1,2 @@
+GDTEST_ANALYZER_ERROR
+Expression is of type "String" so it can't be of type "int".
diff --git a/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_literal_bool.gd b/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_literal_bool.gd
new file mode 100644
index 0000000000..060a8bedf9
--- /dev/null
+++ b/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_literal_bool.gd
@@ -0,0 +1,3 @@
+func test():
+	for x in true:
+		pass
diff --git a/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_literal_bool.out b/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_literal_bool.out
new file mode 100644
index 0000000000..94cb038885
--- /dev/null
+++ b/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_literal_bool.out
@@ -0,0 +1,2 @@
+GDTEST_ANALYZER_ERROR
+Unable to iterate on value of type "bool".
diff --git a/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_literal_int.gd b/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_literal_int.gd
new file mode 100644
index 0000000000..6cfc822482
--- /dev/null
+++ b/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_literal_int.gd
@@ -0,0 +1,4 @@
+func test():
+	for x in 1:
+		if x is String:
+			pass
diff --git a/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_literal_int.out b/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_literal_int.out
new file mode 100644
index 0000000000..54c190cf8a
--- /dev/null
+++ b/modules/gdscript/tests/scripts/analyzer/errors/for_loop_on_literal_int.out
@@ -0,0 +1,2 @@
+GDTEST_ANALYZER_ERROR
+Expression is of type "int" so it can't be of type "String".
diff --git a/modules/gdscript/tests/scripts/analyzer/features/for_loop_on_variant.gd b/modules/gdscript/tests/scripts/analyzer/features/for_loop_on_variant.gd
new file mode 100644
index 0000000000..7b74be6f2c
--- /dev/null
+++ b/modules/gdscript/tests/scripts/analyzer/features/for_loop_on_variant.gd
@@ -0,0 +1,15 @@
+func test():
+	var variant_int: Variant = 1
+	var weak_int = 1
+
+	for x in variant_int:
+		if x is String:
+			print('never')
+		print(x)
+
+	for x in weak_int:
+		if x is String:
+			print('never')
+		print(x)
+
+	print('ok')
diff --git a/modules/gdscript/tests/scripts/analyzer/features/for_loop_on_variant.out b/modules/gdscript/tests/scripts/analyzer/features/for_loop_on_variant.out
new file mode 100644
index 0000000000..7677671cfd
--- /dev/null
+++ b/modules/gdscript/tests/scripts/analyzer/features/for_loop_on_variant.out
@@ -0,0 +1,4 @@
+GDTEST_OK
+0
+0
+ok
diff --git a/modules/gdscript/tests/scripts/runtime/features/for_loop_iterator_types.gd b/modules/gdscript/tests/scripts/runtime/features/for_loop_iterator_types.gd
new file mode 100644
index 0000000000..81355e0255
--- /dev/null
+++ b/modules/gdscript/tests/scripts/runtime/features/for_loop_iterator_types.gd
@@ -0,0 +1,51 @@
+const constant_float = 1.0
+const constant_int = 1
+enum { enum_value = 1 }
+
+class Iterator:
+	func _iter_init(_count):
+		return true
+	func _iter_next(_count):
+		return false
+	func _iter_get(_count) -> StringName:
+		return &'custom'
+
+func test():
+	var hard_float := 1.0
+	var hard_int := 1
+	var hard_string := '0'
+	var hard_iterator := Iterator.new()
+
+	var variant_float: Variant = hard_float
+	var variant_int: Variant = hard_int
+	var variant_string: Variant = hard_string
+	var variant_iterator: Variant = hard_iterator
+
+	for i in 1.0:
+		print(typeof(i) == TYPE_FLOAT)
+	for i in 1:
+		print(typeof(i) == TYPE_INT)
+	for i in 'a':
+		print(typeof(i) == TYPE_STRING)
+	for i in Iterator.new():
+		print(typeof(i) == TYPE_STRING_NAME)
+
+	for i in hard_float:
+		print(typeof(i) == TYPE_FLOAT)
+	for i in hard_int:
+		print(typeof(i) == TYPE_INT)
+	for i in hard_string:
+		print(typeof(i) == TYPE_STRING)
+	for i in hard_iterator:
+		print(typeof(i) == TYPE_STRING_NAME)
+
+	for i in variant_float:
+		print(typeof(i) == TYPE_FLOAT)
+	for i in variant_int:
+		print(typeof(i) == TYPE_INT)
+	for i in variant_string:
+		print(typeof(i) == TYPE_STRING)
+	for i in variant_iterator:
+		print(typeof(i) == TYPE_STRING_NAME)
+
+	print('ok')
diff --git a/modules/gdscript/tests/scripts/runtime/features/for_loop_iterator_types.out b/modules/gdscript/tests/scripts/runtime/features/for_loop_iterator_types.out
new file mode 100644
index 0000000000..b3e82d52ef
--- /dev/null
+++ b/modules/gdscript/tests/scripts/runtime/features/for_loop_iterator_types.out
@@ -0,0 +1,14 @@
+GDTEST_OK
+true
+true
+true
+true
+true
+true
+true
+true
+true
+true
+true
+true
+ok