remove rng from class var

Author: babacry

cirq-core/cirq/transformers/gauge_compiling/multi_moment_cphase_gauge.py

@@ -182,10 +182,12 @@ class CPhaseGaugeTransformerMM(MultiMomentGaugeTransformer):
     def __init__(self, supported_gates=_SUPPORTED_GATESET):
         super().__init__(target=_TARGET_GATESET, supported_gates=supported_gates)
 
-    def sample_left_moment(self, active_qubits: frozenset[ops.Qid]) -> circuits.Moment:
+    def sample_left_moment(
+        self, active_qubits: frozenset[ops.Qid], rng: np.random.Generator = np.random.default_rng()
+    ) -> circuits.Moment:
         return circuits.Moment(
             [
-                self.rng.choice(
+                rng.choice(
                     np.array([ops.I, ops.X, ops.Y, ops.Z], dtype=ops.Gate),
                     p=[0.25, 0.25, 0.25, 0.25],
                 ).on(q)

cirq-core/cirq/transformers/gauge_compiling/multi_moment_gauge_compiling.py

@@ -12,12 +12,11 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-"""Creates the abstraction for multi moment gauge compiling as a cirq transformer."""
-
-from __future__ import annotations
+"""Defines the abstraction for multi-moment gauge compiling as a cirq transformer."""
 
 import abc
 
+from attrs import field, frozen
 import numpy as np
 
 from cirq import circuits, ops
@@ -45,7 +44,6 @@ def __init__(
         self,
         target: ops.Gate | ops.Gateset | ops.GateFamily,
         supported_gates: ops.Gateset = ops.Gateset(),
-        rng: np.random.Generator = np.random.default_rng(),
     ) -> None:
         """Constructs a MultiMomentGaugeTransformer.
 
@@ -56,15 +54,13 @@ def __init__(
             supported_gates: Determines what other gates, in addition to the target gates,
               are permitted within the gauge moments. If a moment contains a gate not found
               in either target or supported_gates, it won't be gauged.
-            rng: A pseudorandom number generator.
         """
         self.target = ops.GateFamily(target) if isinstance(target, ops.Gate) else target
         self.supported_gates = (
             ops.GateFamily(supported_gates)
             if isinstance(supported_gates, ops.Gate)
             else supported_gates
         )
-        self.rng = rng
 
     @abc.abstractmethod
     def gauge_on_moments(self, moments_to_gauge: list[circuits.Moment]) -> list[circuits.Moment]:
@@ -78,11 +74,14 @@ def gauge_on_moments(self, moments_to_gauge: list[circuits.Moment]) -> list[circ
         """
 
     @abc.abstractmethod
-    def sample_left_moment(self, active_qubits: frozenset[ops.Qid]) -> circuits.Moment:
+    def sample_left_moment(
+        self, active_qubits: frozenset[ops.Qid], rng: np.random.Generator
+    ) -> circuits.Moment:
         """Samples a random single-qubit moment to be inserted before the target block.
 
         Args:
             active_qubits: The qubits on which the sampled gates should be applied.
+            rng: A pseudorandom number generator.
 
         Returns:
             The sampled moment.