Expand Up @@ -569,15 +569,15 @@ def _remove_redundant_union_items(items: list[Type], keep_erased: bool) -> list[ return items

def _get_type_special_method_bool_ret_type(t: Type) -> Type | None: def _get_type_method_ret_type(t: Type, *, name: str) -> Type | None: t = get_proper_type(t)
if isinstance(t, Instance): bool_method = t.type.get("__bool__") if bool_method: callee = get_proper_type(bool_method.type) if isinstance(callee, CallableType): return callee.ret_type sym = t.type.get(name) if sym: sym_type = get_proper_type(sym.type) if isinstance(sym_type, CallableType): return sym_type.ret_type
return None
Expand All @@ -600,7 +600,9 @@ def true_only(t: Type) -> ProperType: can_be_true_items = [item for item in new_items if item.can_be_true] return make_simplified_union(can_be_true_items, line=t.line, column=t.column) else: ret_type = _get_type_special_method_bool_ret_type(t) ret_type = _get_type_method_ret_type(t, name="__bool__") or _get_type_method_ret_type( t, name="__len__" )
if ret_type and not ret_type.can_be_true: return UninhabitedType(line=t.line, column=t.column) Expand Down Expand Up @@ -633,9 +635,14 @@ def false_only(t: Type) -> ProperType: can_be_false_items = [item for item in new_items if item.can_be_false] return make_simplified_union(can_be_false_items, line=t.line, column=t.column) else: ret_type = _get_type_special_method_bool_ret_type(t) ret_type = _get_type_method_ret_type(t, name="__bool__") or _get_type_method_ret_type( t, name="__len__" )
if ret_type and not ret_type.can_be_false: if ret_type: if not ret_type.can_be_false: return UninhabitedType(line=t.line) elif isinstance(t, Instance) and t.type.is_final: return UninhabitedType(line=t.line)
new_t = copy_type(t) Expand Down