add some checks for all this

Author: Gobot1234

stdlib/@tests/test_cases/builtins/check_bool.py

@@ -0,0 +1,21 @@
+from typing_extensions import Literal, assert_type
+
+
+assert_type(bool(), Literal[False])
+assert_type(bool(False), Literal[False])
+assert_type(bool(True), Literal[True])
+assert_type(bool(42), bool)
+
+
+class Truthy:
+    def __bool__(self) -> Literal[True]:
+        return True
+
+
+class Falsy:
+    def __bool__(self) -> Literal[False]:
+        return False
+
+
+assert_type(bool(Truthy()), Literal[True])
+assert_type(bool(Falsy()), Literal[False])