Fix mypy type errors and remove typos

Author: tanujkhattar

Diff for: cirq-core/cirq/transformers/transformer_api.py

@@ -22,6 +22,7 @@
 from typing import (
     cast,
     Any,
+    Callable,
     Tuple,
     Hashable,
     List,
@@ -30,6 +31,7 @@
     Type,
     TYPE_CHECKING,
     TypeVar,
+    Union,
 )
 from typing_extensions import Protocol
 
@@ -235,6 +237,16 @@ def __call__(
 
 _TRANSFORMER_T = TypeVar('_TRANSFORMER_T', bound=TRANSFORMER)
 _TRANSFORMER_CLS_T = TypeVar('_TRANSFORMER_CLS_T', bound=Type[TRANSFORMER])
+_TRANSFORMER_OR_CLS_T = TypeVar(
+    '_TRANSFORMER_OR_CLS_T', bound=Union[TRANSFORMER, Type[TRANSFORMER]]
+)
+
+
+@overload
+def transformer(
+    *, add_support_for_deep: bool = False
+) -> Callable[[_TRANSFORMER_OR_CLS_T], _TRANSFORMER_OR_CLS_T]:
+    pass
 
 
 @overload

Diff for: cirq-core/cirq/transformers/transformer_api_test.py

@@ -89,11 +89,9 @@ def make_transformer_func(add_support_for_deep: bool = False) -> cirq.TRANSFORME
     def mock_tranformer_func(
         circuit: cirq.AbstractCircuit, *, context: Optional[cirq.TransformerContext] = None
     ) -> cirq.Circuit:
-        print("CALLED:", circuit, context, sep="\n\n----------\n\n")
         my_mock(circuit, context)
         return circuit.unfreeze()
 
-    # mock_transformer = mock_tranformer_func(add_support_for_deep)
     mock_tranformer_func.mock = my_mock  # type: ignore
     return mock_tranformer_func
 
@@ -141,9 +139,6 @@ def test_transformer_decorator_with_defaults(transformer):
     transformer.mock.assert_called_with(circuit, context, 1e-2, CustomArg(12))
 
 
-# from unittest.mock import patch, call
-
-
 @pytest.mark.parametrize(
     'transformer, supports_deep',
     [
@@ -154,9 +149,9 @@ def test_transformer_decorator_with_defaults(transformer):
     ],
 )
 def test_transformer_decorator_adds_support_for_deep(transformer, supports_deep):
-    q1, q2 = cirq.LineQubit.range(2)
-    c_nested_x = cirq.FrozenCircuit(cirq.X(q1))
-    c_nested_y = cirq.FrozenCircuit(cirq.Y(q1))
+    q = cirq.NamedQubit("q")
+    c_nested_x = cirq.FrozenCircuit(cirq.X(q))
+    c_nested_y = cirq.FrozenCircuit(cirq.Y(q))
     c_nested_xy = cirq.FrozenCircuit(
         cirq.CircuitOperation(c_nested_x).repeat(5).with_tags("ignore"),
         cirq.CircuitOperation(c_nested_y).repeat(7).with_tags("preserve_tag"),