add test for paulirot

Author: kipawaa

…test/lit/GraphDecomposition/TestQPD.mlir …d/test/lit/GraphDecomposition/QPD/S.mlirfrontend/test/lit/GraphDecomposition/TestQPD.mlir renamed to frontend/test/lit/GraphDecomposition/QPD/S.mlir frontend/test/lit/GraphDecomposition/TestQPD.mlir renamed to frontend/test/lit/GraphDecomposition/QPD/S.mlir

@@ -12,12 +12,9 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-// Test that graph-decomposition is able to use compile-time python decompositions
-
 // RUN: catalyst --tool=opt --pass-pipeline='builtin.module(graph-decomposition{gate-set=PhaseShift=1.0})' %s | FileCheck %s
 
-
-func.func @circuit() -> !quantum.bit {
+func.func @S() -> !quantum.bit {
   %reg = quantum.alloc(1): !quantum.reg
   %0 = quantum.extract %reg[0] : !quantum.reg -> !quantum.bit
 
@@ -26,5 +23,3 @@ func.func @circuit() -> !quantum.bit {
   %out_qubits = quantum.custom "S"() %0 : !quantum.bit
   return %out_qubits : !quantum.bit
 }
-
-// TODO: add a tests for more complicated operators once they're migrated

frontend/test/lit/GraphDecomposition/QPD/paulirot.mlir

@@ -0,0 +1,24 @@
+// Copyright 2026 Xanadu Quantum Technologies Inc.
+
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// RUN: catalyst --tool=opt --pass-pipeline='builtin.module(graph-decomposition{gate-set=Hadamard=1.0,MultiRZ=1.0})' %s | FileCheck %s
+
+func.func @paulirot(%angle: f64, %q1: !quantum.bit, %q2: !quantum.bit) {
+  // CHECK-NOT: quantum.paulirot
+  // CHECK: Hadamard
+  // CHECK: quantum.multirz
+  // CHECK: Hadamard
+  %qout:2 = quantum.paulirot ["Z", "X"](%angle) %q1, %q2 : !quantum.bit, !quantum.bit
+  return
+}