Update deprecation message and ignore deprecation warning in the non-…

…deprecated PhaseOracle
Qiskit · Feb 12, 2025 · 4510aee · 4510aee
1 parent c81ee1a
commit 4510aee
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Showing 5 changed files with 17 additions and 18 deletions.
diff --git a/qiskit/circuit/classicalfunction/__init__.py b/qiskit/circuit/classicalfunction/__init__.py
@@ -128,7 +128,9 @@ def grover_oracle(a: Int1, b: Int1, c: Int1, d: Int1) -> Int1:
 @deprecate_func(
     since="1.4",
     removal_timeline="in Qiskit 2.0",
-    additional_msg="Use `PhaseOracle` or `BitFlipOracle` instead",
+    additional_msg="Use `PhaseOracle` instead, which can be turned into a "
+    "bit-flip oracle by applying Hadamard gates on the target "
+    "qubit before and after the instruction.",
 )
 def classical_function(func):
     """

diff --git a/qiskit/circuit/classicalfunction/boolean_expression.py b/qiskit/circuit/classicalfunction/boolean_expression.py
@@ -28,7 +28,9 @@ class BooleanExpression(ClassicalElement):
     @deprecate_func(
         since="1.4",
         removal_timeline="in Qiskit 2.0",
-        additional_msg="Use `PhaseOracle` or `BitFlipOracle` instead",
+        additional_msg="Use `PhaseOracle` instead, which can be turned into a "
+        "bit-flip oracle by applying Hadamard gates on the target "
+        "qubit before and after the instruction.",
     )
     def __init__(self, expression: str, name: str = None, var_order: list = None) -> None:
         """

diff --git a/qiskit/circuit/classicalfunction/classicalfunction.py b/qiskit/circuit/classicalfunction/classicalfunction.py
@@ -31,7 +31,9 @@ class ClassicalFunction(ClassicalElement):
     @deprecate_func(
         since="1.4",
         removal_timeline="in Qiskit 2.0",
-        additional_msg="Use `PhaseOracle` or `BitFlipOracle` instead",
+        additional_msg="Use `PhaseOracle` instead, which can be turned into a "
+        "bit-flip oracle by applying Hadamard gates on the target "
+        "qubit before and after the instruction.",
     )
     def __init__(self, source, name=None):
         """Creates a ``ClassicalFunction`` from Python source code in ``source``.

diff --git a/qiskit/circuit/library/phase_oracle.py b/qiskit/circuit/library/phase_oracle.py
@@ -63,6 +63,11 @@ def __init__(
             var_order(list): A list with the order in which variables will be created.
                (default: by appearance)
         """
+        # ignore deprecation warning for BooleanExpression; implementation is changing in 2.0
+        import warnings
+
+        warnings.simplefilter("ignore", DeprecationWarning)
+
         from qiskit.circuit.classicalfunction.boolean_expression import BooleanExpression
         from qiskit.circuit.classicalfunction.classical_element import ClassicalElement
 

diff --git a/test/python/circuit/library/test_phase_oracle.py b/test/python/circuit/library/test_phase_oracle.py
@@ -37,11 +37,7 @@ class TestPhaseOracle(QiskitTestCase):
     @unpack
     def test_evaluate_bitstring(self, expression, input_bitstring, expected):
         """PhaseOracle(...).evaluate_bitstring"""
-        with self.assertWarnsRegex(
-            DeprecationWarning,
-            expected_regex="BooleanExpression`` is deprecated as of qiskit 1.4",
-        ):
-            oracle = PhaseOracle(expression)
+        oracle = PhaseOracle(expression)
         result = oracle.evaluate_bitstring(input_bitstring)
         self.assertEqual(result, expected)
 
@@ -54,11 +50,7 @@ def test_evaluate_bitstring(self, expression, input_bitstring, expected):
     @unpack
     def test_statevector(self, expression, good_states):
         """Circuit generation"""
-        with self.assertWarnsRegex(
-            DeprecationWarning,
-            expected_regex="BooleanExpression`` is deprecated as of qiskit 1.4",
-        ):
-            oracle = PhaseOracle(expression)
+        oracle = PhaseOracle(expression)
         num_qubits = oracle.num_qubits
         circuit = QuantumCircuit(num_qubits)
         circuit.h(range(num_qubits))
@@ -84,11 +76,7 @@ def test_statevector(self, expression, good_states):
     @unpack
     def test_variable_order(self, expression, var_order, good_states):
         """Circuit generation"""
-        with self.assertWarnsRegex(
-            DeprecationWarning,
-            expected_regex="BooleanExpression`` is deprecated as of qiskit 1.4",
-        ):
-            oracle = PhaseOracle(expression, var_order=var_order)
+        oracle = PhaseOracle(expression, var_order=var_order)
         num_qubits = oracle.num_qubits
         circuit = QuantumCircuit(num_qubits)
         circuit.h(range(num_qubits))