Replace assert qml.equal with qml.assert_equal in tests (#6709)

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------------------------------------------------------------------------------------------------------------

**Context:**

**Description of the Change:**

**Benefits:**

**Possible Drawbacks:**

**Related GitHub Issues:**

tests/data/attributes/test_pytree.py

@@ -113,4 +113,4 @@ def test_quantum_scripts(shots):
     """Test that ``QuantumScript`` can be serialized as Pytrees."""
     script = qml.tape.QuantumScript([qml.X(0)], shots=shots)
 
-    assert qml.equal(DatasetPyTree(script).get_value(), script)
+    qml.assert_equal(DatasetPyTree(script).get_value(), script)

tests/devices/test_legacy_facade.py

@@ -163,7 +163,7 @@ def test_legacy_device_expand_fn():
         [qml.X(0), qml.CNOT((0, 1)), qml.RX(0.5, 0), qml.CNOT((0, 1))], [qml.state()]
     )
     (new_tape,), fn = legacy_device_expand_fn(tape, device=DummyDevice())
-    assert qml.equal(new_tape, expected)
+    qml.assert_equal(new_tape, expected)
     assert fn(("A",)) == "A"
 
 
@@ -173,8 +173,8 @@ def test_legacy_device_batch_transform():
     tape = qml.tape.QuantumScript([], [qml.expval(qml.X(0) + qml.Y(0))])
     (tape1, tape2), fn = legacy_device_batch_transform(tape, device=DummyDevice())
 
-    assert qml.equal(tape1, qml.tape.QuantumScript([], [qml.expval(qml.X(0))]))
-    assert qml.equal(tape2, qml.tape.QuantumScript([], [qml.expval(qml.Y(0))]))
+    qml.assert_equal(tape1, qml.tape.QuantumScript([], [qml.expval(qml.X(0))]))
+    qml.assert_equal(tape2, qml.tape.QuantumScript([], [qml.expval(qml.Y(0))]))
     assert fn((1.0, 2.0)) == np.array(3.0)
 
 

tests/ops/op_math/test_controlled.py

@@ -1034,11 +1034,11 @@ def test_differentiable_one_qubit_special_unitary_multiple_ctrl(self):
         op = qml.ctrl(qml.RZ(qml.numpy.array(theta), 0), (1, 2, 3, 4))
         decomp = op.decomposition()
 
-        assert qml.equal(decomp[0], qml.CRZ(qml.numpy.array(theta), [4, 0]))
-        assert qml.equal(decomp[1], qml.MultiControlledX(wires=[1, 2, 3, 0]))
-        assert qml.equal(decomp[2], qml.CRZ(qml.numpy.array(-theta / 2), wires=[4, 0]))
-        assert qml.equal(decomp[3], qml.MultiControlledX(wires=[1, 2, 3, 0]))
-        assert qml.equal(decomp[4], qml.CRZ(qml.numpy.array(-theta / 2), wires=[4, 0]))
+        qml.assert_equal(decomp[0], qml.CRZ(qml.numpy.array(theta), [4, 0]))
+        qml.assert_equal(decomp[1], qml.MultiControlledX(wires=[1, 2, 3, 0]))
+        qml.assert_equal(decomp[2], qml.CRZ(qml.numpy.array(-theta / 2), wires=[4, 0]))
+        qml.assert_equal(decomp[3], qml.MultiControlledX(wires=[1, 2, 3, 0]))
+        qml.assert_equal(decomp[4], qml.CRZ(qml.numpy.array(-theta / 2), wires=[4, 0]))
 
         decomp_mat = qml.matrix(op.decomposition, wire_order=op.wires)()
         assert qml.math.allclose(op.matrix(), decomp_mat)

tests/pytrees/test_serialization.py

@@ -213,7 +213,7 @@ def test_pennylane_pytree_roundtrip(obj_in: Any):
     data, struct = flatten(obj_in)
     obj_out = unflatten(data, pytree_structure_load(pytree_structure_dump(struct)))
 
-    assert qml.equal(obj_in, obj_out)
+    qml.assert_equal(obj_in, obj_out)
 
 
 @pytest.mark.parametrize(

tests/tape/test_qscript.py

@@ -826,13 +826,13 @@ def test_setting_trainable_params_to_none(self):
         )
 
         assert tape.num_params == 1
-        assert qml.equal(tape.get_operation(0)[0], qml.RY(2.3, 1))
+        qml.assert_equal(tape.get_operation(0)[0], qml.RY(2.3, 1))
 
         new_tape = tape.copy(trainable_params=None)
 
         assert new_tape.num_params == 2
-        assert qml.equal(new_tape.get_operation(0)[0], qml.RX(1.2, 0))
-        assert qml.equal(new_tape.get_operation(1)[0], qml.RY(2.3, 1))
+        qml.assert_equal(new_tape.get_operation(0)[0], qml.RX(1.2, 0))
+        qml.assert_equal(new_tape.get_operation(1)[0], qml.RY(2.3, 1))
 
     def test_setting_measurements_and_trainable_params(self):
         """Test that when explicitly setting both measurements and trainable params, the

tests/templates/test_subroutines/test_gqsp.py

@@ -130,7 +130,7 @@ def test_decomposition(self):
         ]
 
         for op1, op2 in zip(decomposition, expected):
-            assert qml.equal(op1, op2)
+            qml.assert_equal(op1, op2)
 
     @pytest.mark.jax
     def test_gqsp_jax(self):

tests/templates/test_subroutines/test_multiplier.py

@@ -40,7 +40,7 @@ def test_mul_out_k_mod():
     assert op[1].name == "ControlledSequence"
     assert op[2].name == "Adjoint(QFT)"
     print(op[1].base)
-    assert qml.equal(op[1].base, qml.PhaseAdder(2, x_wires=[4, 5]))
+    qml.assert_equal(op[1].base, qml.PhaseAdder(2, x_wires=[4, 5]))
 
 
 class TestMultiplier:

tests/templates/test_subroutines/test_prepselprep.py

@@ -264,7 +264,7 @@ def test_copy(self):
         op = qml.PrepSelPrep(lcu, control=0)
         op_copy = copy.copy(op)
 
-        assert qml.equal(op, op_copy)
+        qml.assert_equal(op, op_copy)
 
     @pytest.mark.parametrize(
         ("lcu"),