def test_not_overlapping_barriers(self):
""" Test two barriers with no overlap are not merged
(NB in these pictures they look like 1 barrier but they are
actually 2 distinct barriers, this is just how the text
drawer draws them)
░ ░
q_0: |0>─░─ q_0: |0>─░─
░ -> ░
q_1: |0>─░─ q_1: |0>─░─
░ ░
"""
qr = QuantumRegister(2, 'q')
circuit = QuantumCircuit(qr)
circuit.barrier(qr[0])
circuit.barrier(qr[1])
expected = QuantumCircuit(qr)
expected.barrier(qr[0])
expected.barrier(qr[1])
pass_ = MergeAdjacentBarriers()
result = pass_.run(circuit_to_dag(circuit))
self.assertEqual(result, circuit_to_dag(expected))
def test_numerous_identical_barriers(self):
""" Merges 5 identical barriers in a row into one
░ ░ ░ ░ ░ ░ ░
q_0: |0>─░──░──░──░──░──░─ -> q_0: |0>─░─
░ ░ ░ ░ ░ ░ ░
"""
qr = QuantumRegister(1, 'q')
circuit = QuantumCircuit(qr)
circuit.barrier(qr)
circuit.barrier(qr)
circuit.barrier(qr)
circuit.barrier(qr)
circuit.barrier(qr)
circuit.barrier(qr)
expected = QuantumCircuit(qr)
expected.barrier(qr)
expected = QuantumCircuit(qr)
expected.barrier(qr)
pass_ = MergeAdjacentBarriers()
result = pass_.run(circuit_to_dag(circuit))
self.assertEqual(result, circuit_to_dag(expected))
def test_barriers_with_blocking_obstacle_long(self):
""" Test that barriers don't merge if there is an obstacle that
is blocking
░ ┌───┐ ░ ░ ┌───┐ ░
q_0: |0>─░─┤ H ├─░─ q_0: |0>─░─┤ H ├─░─
░ └───┘ ░ -> ░ └───┘ ░
q_1: |0>─────────░─ q_1: |0>─────────░─
░ ░
"""
qr = QuantumRegister(2, 'q')
circuit = QuantumCircuit(qr)
circuit.barrier(qr[0])
circuit.h(qr[0])
circuit.barrier(qr)
expected = QuantumCircuit(qr)
expected.barrier(qr[0])
expected.h(qr[0])
expected.barrier(qr)
pass_ = MergeAdjacentBarriers()
result = pass_.run(circuit_to_dag(circuit))
self.assertEqual(result, circuit_to_dag(expected))
def test_barriers_with_blocking_obstacle_twoQ(self):
""" Test that barriers don't merge if there is an obstacle that
is blocking
░ ░ ░ ░
q_0: |0>─░───────░─ q_0: |0>─░───────░─
░ ░ ░ ░
q_1: |0>─░───■───── -> q_1: |0>─░───■─────
░ ┌─┴─┐ ░ ░ ┌─┴─┐ ░
q_2: |0>───┤ X ├─░─ q_2: |0>───┤ X ├─░─
└───┘ ░ └───┘ ░
"""
qr = QuantumRegister(3, 'q')
circuit = QuantumCircuit(qr)
circuit.barrier(0, 1)
circuit.cx(1, 2)
circuit.barrier(0, 2)
expected = QuantumCircuit(qr)
expected.barrier(0, 1)
expected.cx(1, 2)
expected.barrier(0, 2)
pass_ = MergeAdjacentBarriers()
result = pass_.run(circuit_to_dag(circuit))
self.assertEqual(result, circuit_to_dag(expected))
def test_two_identical_barriers(self):
"""Merges two barriers that are identical into one
░ ░ ░
q_0: |0>─░──░─ -> q_0: |0>─░─
░ ░ ░
"""
qr = QuantumRegister(1, "q")
circuit = QuantumCircuit(qr)
circuit.barrier(qr)
circuit.barrier(qr)
expected = QuantumCircuit(qr)
expected.barrier(qr)
pass_ = MergeAdjacentBarriers()
result = pass_.run(circuit_to_dag(circuit))
self.assertEqual(result, circuit_to_dag(expected))
def test_barriers_of_different_sizes(self):
""" Test two barriers of different sizes are merged into one
░ ░ ░
q_0: |0>─░──░─ q_0: |0>─░─
░ ░ -> ░
q_1: |0>────░─ q_1: |0>─░─
░ ░
"""
qr = QuantumRegister(2, 'q')
circuit = QuantumCircuit(qr)
circuit.barrier(qr[0])
circuit.barrier(qr)
expected = QuantumCircuit(qr)
expected.barrier(qr)
pass_ = MergeAdjacentBarriers()
result = pass_.run(circuit_to_dag(circuit))
self.assertEqual(result, circuit_to_dag(expected))
def test_barriers_with_obstacle_after(self):
""" Test with an obstacle after the larger barrier
░ ░ ░
q_0: |0>─░───░── q_0: |0>─░──────
░ ┌───┐ -> ░ ┌───┐
q_1: |0>─░─┤ H ├ q_1: |0>─░─┤ H ├
░ └───┘ ░ └───┘
"""
qr = QuantumRegister(2, 'q')
circuit = QuantumCircuit(qr)
circuit.barrier(qr)
circuit.barrier(qr[0])
circuit.h(qr[1])
expected = QuantumCircuit(qr)
expected.barrier(qr)
expected.h(qr[1])
pass_ = MergeAdjacentBarriers()
result = pass_.run(circuit_to_dag(circuit))
self.assertEqual(result, circuit_to_dag(expected))
def test_barriers_with_obstacle_before(self):
""" Test with an obstacle before the larger barrier
░ ░ ░
q_0: |0>──░───░─ q_0: |0>──────░─
┌───┐ ░ -> ┌───┐ ░
q_1: |0>┤ H ├─░─ q_1: |0>┤ H ├─░─
└───┘ ░ └───┘ ░
"""
qr = QuantumRegister(2, 'q')
circuit = QuantumCircuit(qr)
circuit.barrier(qr[0])
circuit.h(qr[1])
circuit.barrier(qr)
expected = QuantumCircuit(qr)
expected.h(qr[1])
expected.barrier(qr)
pass_ = MergeAdjacentBarriers()
result = pass_.run(circuit_to_dag(circuit))
self.assertEqual(result, circuit_to_dag(expected))