Bump pylint version to unify across elements (#3635)

* Bump pylint version to unify across elements

This commit bumps the pinned versions of pylint and astroid to the
lastest versions of both. We are unifying the version of both used in CI
across all the elements to these versions to have a consistent
experience with the linters when working across the elements.

This adjusts the terra code to make the newer versions pass. This
involves disabling one rule globally because it doesn't apply to how
terra is structured, adding per file (and 1 per line) disable for usage
of numpy that pylint can't track because of the c extensions, and a
number of code changes to fix failing rules which are marked by the new
version.

Fixes #3629

* Fix tests

* Rename kron() args to avoid ordering confusion

* Fix lint failures introduced in recent patches

Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

.pylintrc

@@ -73,6 +73,7 @@ disable=no-self-use,        # disabled as it is too verbose
     unnecessary-pass,   # allow for methods with just "pass", for clarity
     no-else-return,     # relax "elif" after a clause with a return
     docstring-first-line-empty, # relax docstring style
+    import-outside-toplevel
 
 
 

constraints.txt

@@ -1,4 +1,4 @@
-astroid==2.2.5
-pylint==2.3.1
+astroid==2.3.3
+pylint==2.4.4
 matplotlib==3.2.0rc1;python_version=='3.8'
 nbformat==4.4.0

qiskit/assembler/assemble_schedules.py

@@ -89,7 +89,7 @@ def assemble_schedules(schedules, qobj_id, qobj_header, run_config):
                 # delay instructions are ignored as timing is explicit within qobj
                 continue
 
-            elif isinstance(instruction, PulseInstruction):
+            if isinstance(instruction, PulseInstruction):
                 name = instruction.command.name
                 if name in user_pulselib and instruction.command != user_pulselib[name]:
                     name = "{0}-{1:x}".format(name, hash(instruction.command.samples.tostring()))

qiskit/converters/ast_to_dag.py

@@ -159,7 +159,7 @@ class AstInterpreter:
             # A qubit or qreg or creg
             if not self.bit_stack[-1]:
                 # Global scope
-                return [bit for bit in reg]
+                return list(reg)
             else:
                 # local scope
                 if node.name in self.bit_stack[-1]:

qiskit/dagcircuit/dagcircuit.py

@@ -210,7 +210,7 @@ class DAGCircuit:
         Returns:
             list[Clbit]: list of classical bits
         """
-        return [] if cond is None else [cbit for cbit in cond[0]]
+        return [] if cond is None else list(cond[0])
 
     def _add_op_node(self, op, qargs, cargs, condition=None):
         """Add a new operation node to the graph and assign properties.
@@ -569,7 +569,7 @@ class DAGCircuit:
         """
         for wire in self.wires:
             nodes = self.nodes_on_wire(wire, only_ops=False)
-            if len([i for i in nodes]) == 2:
+            if len(list(nodes)) == 2:
                 yield wire
 
     def size(self):
@@ -791,11 +791,7 @@ class DAGCircuit:
 
         condition_bit_list = self._bits_in_condition(node.condition)
 
-        wire_map = {k: v for k, v in zip(wires,
-                                         [i for s in [node.qargs,
-                                                      node.cargs,
-                                                      condition_bit_list]
-                                          for i in s])}
+        wire_map = dict(zip(wires, list(node.qargs) + list(node.cargs) + list(condition_bit_list)))
         self._check_wiremap_validity(wire_map, wires, self.input_map)
         pred_map, succ_map = self._make_pred_succ_maps(node)
         full_pred_map, full_succ_map = self._full_pred_succ_maps(pred_map, succ_map,
@@ -1187,7 +1183,7 @@ class DAGCircuit:
     def multigraph_layers(self):
         """Yield layers of the multigraph."""
         predecessor_count = dict()  # Dict[node, predecessors not visited]
-        cur_layer = [node for node in self.input_map.values()]
+        cur_layer = self.input_map.values()
         yield cur_layer
         next_layer = []
         while cur_layer:

qiskit/extensions/quantum_initializer/isometry.py

@@ -16,6 +16,7 @@
 # pylint: disable=unused-variable
 # pylint: disable=missing-param-doc
 # pylint: disable=missing-type-doc
+# pylint: disable=no-member
 
 """
 Generic isometries from m to n qubits.
@@ -416,7 +417,7 @@ def _get_qubits_by_label(labels, qubits, num_qubits):
 
 
 def _reverse_qubit_oder(qubits):
-    return [q for q in reversed(qubits)]
+    return list(reversed(qubits))
 
 
 # Convert list of binary digits to integer

qiskit/extensions/standard/barrier.py

@@ -57,7 +57,7 @@ def barrier(self, *qargs):
         elif isinstance(qarg, list):
             qubits.extend(qarg)
         elif isinstance(qarg, range):
-            qubits.extend([i for i in qarg])
+            qubits.extend(list(qarg))
         elif isinstance(qarg, slice):
             qubits.extend(self.qubits[qarg])
         else:

qiskit/extensions/standard/multi_control_rotation_gates.py

@@ -94,7 +94,7 @@ def mcrx(self, theta, q_controls, q_target, use_basis_gates=False):
 
     # check controls
     if isinstance(q_controls, QuantumRegister):
-        control_qubits = [qb for qb in q_controls]
+        control_qubits = list(q_controls)
     elif isinstance(q_controls, list):
         control_qubits = q_controls
     else:
@@ -142,7 +142,7 @@ def mcry(self, theta, q_controls, q_target, q_ancillae, mode='basic',
 
     # check controls
     if isinstance(q_controls, QuantumRegister):
-        control_qubits = [qb for qb in q_controls]
+        control_qubits = list(q_controls)
     elif isinstance(q_controls, list):
         control_qubits = q_controls
     else:
@@ -159,7 +159,7 @@ def mcry(self, theta, q_controls, q_target, q_ancillae, mode='basic',
     if q_ancillae is None:
         ancillary_qubits = []
     elif isinstance(q_ancillae, QuantumRegister):
-        ancillary_qubits = [qb for qb in q_ancillae]
+        ancillary_qubits = list(q_ancillae)
     elif isinstance(q_ancillae, list):
         ancillary_qubits = q_ancillae
     else:
@@ -206,7 +206,7 @@ def mcrz(self, lam, q_controls, q_target, use_basis_gates=False):
 
     # check controls
     if isinstance(q_controls, QuantumRegister):
-        control_qubits = [qb for qb in q_controls]
+        control_qubits = list(q_controls)
     elif isinstance(q_controls, list):
         control_qubits = q_controls
     else:

qiskit/extensions/standard/multi_control_toffoli_gate.py

@@ -274,7 +274,7 @@ def mct(self, q_controls, q_target, q_ancilla, mode='basic'):
     else:
         # check controls
         if isinstance(q_controls, QuantumRegister):
-            control_qubits = [qb for qb in q_controls]
+            control_qubits = list(q_controls)
         elif isinstance(q_controls, list):
             control_qubits = q_controls
         else:
@@ -290,7 +290,7 @@ def mct(self, q_controls, q_target, q_ancilla, mode='basic'):
         if q_ancilla is None:
             ancillary_qubits = []
         elif isinstance(q_ancilla, QuantumRegister):
-            ancillary_qubits = [qb for qb in q_ancilla]
+            ancillary_qubits = list(q_ancilla)
         elif isinstance(q_ancilla, list):
             ancillary_qubits = q_ancilla
         else:

qiskit/pulse/timeslots.py

@@ -280,7 +280,7 @@ class TimeslotCollection:
 
             if interval.start >= ch_interval.stop:
                 break
-            elif interval.has_overlap(ch_interval):
+            if interval.has_overlap(ch_interval):
                 overlap_start = interval.start if interval.start > ch_interval.start \
                     else ch_interval.start
                 overlap_end = ch_interval.stop if interval.stop > ch_interval.stop \

qiskit/quantum_info/operators/channel/chi.py

@@ -12,6 +12,8 @@
 # copyright notice, and modified files need to carry a notice indicating
 # that they have been altered from the originals.
 
+# pylint: disable=unpacking-non-sequence
+
 """
 Chi-matrix representation of a Quantum Channel.
 

qiskit/quantum_info/operators/channel/choi.py

@@ -12,6 +12,8 @@
 # copyright notice, and modified files need to carry a notice indicating
 # that they have been altered from the originals.
 
+# pylint: disable=unpacking-non-sequence
+
 """
 Choi-matrix representation of a Quantum Channel.
 

qiskit/quantum_info/operators/channel/kraus.py

@@ -406,7 +406,7 @@ class Kraus(QuantumChannel):
         if reverse:
             input_dims = self.input_dims() + other.input_dims()
             output_dims = self.output_dims() + other.output_dims()
-            kab_l = [np.kron(b, a) for a in ka_l for b in kb_l]
+            kab_l = [np.kron(b_in, a_in) for a_in in ka_l for b_in in kb_l]
         else:
             input_dims = other.input_dims() + self.input_dims()
             output_dims = other.output_dims() + self.output_dims()
@@ -419,7 +419,7 @@ class Kraus(QuantumChannel):
             if kb_r is None:
                 kb_r = kb_l
             if reverse:
-                kab_r = [np.kron(b, a) for a in ka_r for b in kb_r]
+                kab_r = [np.kron(b_in, a_in) for a_in in ka_r for b_in in kb_r]
             else:
                 kab_r = [np.kron(a, b) for a in ka_r for b in kb_r]
         data = (kab_l, kab_r)

qiskit/quantum_info/operators/channel/ptm.py

@@ -12,6 +12,8 @@
 # copyright notice, and modified files need to carry a notice indicating
 # that they have been altered from the originals.
 
+# pylint: disable=unpacking-non-sequence
+
 """
 Pauli Transfer Matrix (PTM) representation of a Quantum Channel.
 

qiskit/quantum_info/operators/channel/superop.py

@@ -11,6 +11,9 @@
 # Any modifications or derivative works of this code must retain this
 # copyright notice, and modified files need to carry a notice indicating
 # that they have been altered from the originals.
+
+# pylint: disable=unpacking-non-sequence
+
 """
 Superoperator representation of a Quantum Channel.
 

qiskit/quantum_info/operators/channel/transformations.py

@@ -12,7 +12,7 @@
 # copyright notice, and modified files need to carry a notice indicating
 # that they have been altered from the originals.
 
-# pylint: disable=too-many-return-statements,len-as-condition
+# pylint: disable=too-many-return-statements,len-as-condition,unpacking-non-sequence
 
 
 """

qiskit/quantum_info/operators/pauli.py

@@ -155,8 +155,8 @@ class Pauli:
 
     def __repr__(self):
         """Return the representation of self."""
-        z = [p for p in self._z]
-        x = [p for p in self._x]
+        z = list(self._z)
+        x = list(self._x)
 
         ret = self.__class__.__name__ + "(z={}, x={})".format(z, x)
         return ret

qiskit/quantum_info/operators/predicates.py

@@ -12,7 +12,7 @@
 # copyright notice, and modified files need to carry a notice indicating
 # that they have been altered from the originals.
 
-# pylint: disable=len-as-condition
+# pylint: disable=len-as-condition,unsubscriptable-object
 
 """
 Predicates for operators.

qiskit/quantum_info/synthesis/one_qubit_decompose.py

@@ -96,7 +96,8 @@ class OneQubitEulerDecomposer:
         raise QiskitError("OneQubitEulerDecomposer: invalid basis")
 
     def _circuit(self, unitary_mat, simplify=True, atol=DEFAULT_ATOL):
-        theta, phi, lam, phase = self._angles(unitary_mat)
+        # NOTE: The 4th variable is phase to be used later
+        theta, phi, lam, _ = self._angles(unitary_mat)
         if self._basis == 'U3':
             return self._circuit_u3(theta, phi, lam)
         if self._basis == 'U1X':

qiskit/test/decorators.py

@@ -76,14 +76,9 @@ def slow_test(func):
     return _wrapper
 
 
-def _get_credentials(test_object, test_options):
+def _get_credentials():
     """Finds the credentials for a specific test and options.
 
-    Args:
-        test_object (QiskitTestCase): The test object asking for credentials
-        test_options (dict): Options after QISKIT_TESTS was parsed by
-            get_test_options.
-
     Returns:
         Credentials: set of credentials
 
@@ -128,7 +123,7 @@ def requires_qe_access(func):
         if TEST_OPTIONS['skip_online']:
             raise unittest.SkipTest('Skipping online tests')
 
-        credentials = _get_credentials(self, TEST_OPTIONS)
+        credentials = _get_credentials()
         self.using_ibmq_credentials = credentials.is_ibmq()
         kwargs.update({'qe_token': credentials.token,
                        'qe_url': credentials.url})
@@ -173,7 +168,7 @@ def online_test(func):
         if not HAS_NET_CONNECTION:
             raise unittest.SkipTest("Test requires internet connection.")
 
-        credentials = _get_credentials(self, TEST_OPTIONS)
+        credentials = _get_credentials()
         self.using_ibmq_credentials = credentials.is_ibmq()
         kwargs.update({'qe_token': credentials.token,
                        'qe_url': credentials.url})

qiskit/tools/jupyter/jupyter_magics.py

@@ -54,17 +54,16 @@ def _html_checker(job_var, interval, status, header,
         job_status_msg = job_status.value
         if job_status_name == 'ERROR':
             break
+        if job_status_name == 'QUEUED':
+            job_status_msg += ' (%s)' % job_var.queue_position()
+            if job_var.queue_position() is None:
+                interval = 2
+            elif not _interval_set:
+                interval = max(job_var.queue_position(), 2)
         else:
-            if job_status_name == 'QUEUED':
-                job_status_msg += ' (%s)' % job_var.queue_position()
-                if job_var.queue_position() is None:
-                    interval = 2
-                elif not _interval_set:
-                    interval = max(job_var.queue_position(), 2)
-            else:
-                if not _interval_set:
-                    interval = 2
-            status.value = header % (job_status_msg)
+            if not _interval_set:
+                interval = 2
+        status.value = header % (job_status_msg)
 
     status.value = header % (job_status_msg)
 

qiskit/tools/qi/qi.py

@@ -12,7 +12,7 @@
 # copyright notice, and modified files need to carry a notice indicating
 # that they have been altered from the originals.
 
-# pylint: disable=invalid-name
+# pylint: disable=invalid-name,unsupported-assignment-operation
 """
 A collection of useful quantum information functions.
 

qiskit/transpiler/coupling.py

@@ -69,7 +69,7 @@ class CouplingMap:
         Returns:
             Tuple(int,int): Each edge is a pair of physical qubits.
         """
-        return [edge for edge in self.graph.edges()]
+        return list(self.graph.edges())
 
     def add_physical_qubit(self, physical_qubit):
         """Add a physical qubit to the coupling graph as a node.
@@ -119,7 +119,7 @@ class CouplingMap:
     def physical_qubits(self):
         """Returns a sorted list of physical_qubits"""
         if self._qubit_list is None:
-            self._qubit_list = sorted([pqubit for pqubit in self.graph.nodes])
+            self._qubit_list = sorted(self.graph.nodes)
         return self._qubit_list
 
     def is_connected(self):

qiskit/transpiler/layout.py

@@ -298,7 +298,7 @@ class Layout():
         for physical, virtual in enumerate(qubit_list):
             if virtual is None:
                 continue
-            elif isinstance(virtual, Qubit):
+            if isinstance(virtual, Qubit):
                 if virtual in out._v2p:
                     raise LayoutError('Duplicate values not permitted; Layout is bijective.')
                 out[virtual] = physical

qiskit/transpiler/passes/crosstalk_adaptive_schedule.py

@@ -588,7 +588,7 @@ class CrosstalkAdaptiveSchedule(TransformationPass):
         """
         Find the appropriate layer for a gate
         """
-        candidates = [i for i in range(len(layers))]
+        candidates = list(range(len(layers)))
         for i, layer in enumerate(layers):
             candidates = self.filter_candidates(candidates, layer, i, triplet)
         if not candidates:

qiskit/transpiler/passes/mapping/noise_adaptive_layout.py

@@ -88,8 +88,7 @@ class NoiseAdaptiveLayout(AnalysisPass):
                     if item.name == 'gate_error':
                         g_reliab = 1.0 - item.value
                         break
-                    else:
-                        g_reliab = 1.0
+                    g_reliab = 1.0
                 swap_reliab = pow(g_reliab, 3)
                 # convert swap reliability to edge weight
                 # for the Floyd-Warshall shortest weighted paths algorithm

qiskit/transpiler/passes/unroller.py

@@ -73,21 +73,20 @@ class Unroller(TransformationPass):
                 if rule[0][0].name in self.basis:
                     dag.substitute_node(node, rule[0][0], inplace=True)
                     break
-                else:
-                    try:
-                        rule = rule[0][0].definition
-                    except TypeError as err:
-                        raise QiskitError('Error decomposing node {}: {}'.format(node.name, err))
+                try:
+                    rule = rule[0][0].definition
+                except TypeError as err:
+                    raise QiskitError('Error decomposing node {}: {}'.format(node.name, err))
 
             else:
                 if not rule:
                     if rule == []:  # empty node
                         dag.remove_op_node(node)
                         continue
-                    else:           # opaque node
-                        raise QiskitError("Cannot unroll the circuit to the given basis, %s. "
-                                          "No rule to expand instruction %s." %
-                                          (str(self.basis), node.op.name))
+                    # opaque node
+                    raise QiskitError("Cannot unroll the circuit to the given basis, %s. "
+                                      "No rule to expand instruction %s." %
+                                      (str(self.basis), node.op.name))
 
                 # hacky way to build a dag on the same register as the rule is defined
                 # TODO: need anonymous rules to address wires by index

qiskit/transpiler/passmanager.py

@@ -266,8 +266,7 @@ class PassManager:
         for pass_set in self._pass_sets:
             item = {'passes': pass_set['passes']}
             if pass_set['flow_controllers']:
-                item['flow_controllers'] = {controller_name for controller_name in
-                                            pass_set['flow_controllers'].keys()}
+                item['flow_controllers'] = set(pass_set['flow_controllers'].keys())
             else:
                 item['flow_controllers'] = {}
             ret.append(item)

qiskit/transpiler/synthesis/graysynth.py

@@ -120,7 +120,7 @@ def graysynth(cnots, angles, section_size=2):
         [cnots, ilist, qubit] = sta.pop()
         if cnots == []:
             continue
-        elif 0 <= qubit < n_qubits:
+        if 0 <= qubit < n_qubits:
             condition = True
             while condition:
                 condition = False

qiskit/visualization/bloch.py

@@ -46,6 +46,7 @@
 #    OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 ###############################################################################
 
+# pylint: disable=unsubscriptable-object
 
 """Bloch sphere"""
 

qiskit/visualization/circuit_visualization.py

@@ -522,17 +522,16 @@ def _latex_circuit_drawer(circuit,
             try:
                 base = os.path.join(tmpdirname, tmpfilename)
                 subprocess.run(["pdftocairo", "-singlefile", "-png", "-q",
-                                base + '.pdf', base])
+                                base + '.pdf', base], check=True)
                 image = Image.open(base + '.png')
                 image = utils._trim(image)
                 os.remove(base + '.png')
                 if filename:
                     image.save(filename, 'PNG')
-            except OSError as ex:
-                if ex.errno == errno.ENOENT:
-                    logger.warning('WARNING: Unable to convert pdf to image. '
-                                   'Is `poppler` installed? '
-                                   'Skipping circuit drawing...')
+            except (OSError, subprocess.CalledProcessError) as ex:
+                logger.warning('WARNING: Unable to convert pdf to image. '
+                               'Is `poppler` installed? '
+                               'Skipping circuit drawing...')
                 raise
         return image
 

qiskit/visualization/state_visualization.py

@@ -13,7 +13,7 @@
 # that they have been altered from the originals.
 
 # pylint: disable=invalid-name,ungrouped-imports,import-error
-# pylint: disable=inconsistent-return-statements
+# pylint: disable=inconsistent-return-statements,unsubscriptable-object
 
 """
 Visualization functions for quantum states.

qiskit/visualization/text.py

@@ -574,7 +574,7 @@ class TextDrawing():
 
         lines = []
         for layer_group in layer_groups:
-            wires = [i for i in zip(*layer_group)]
+            wires = list(zip(*layer_group))
             lines += self.draw_wires(wires)
 
         return lines
@@ -763,7 +763,7 @@ class TextDrawing():
         Args:
             layer (list): A list of elements.
         """
-        instructions = [instruction for instruction in filter(lambda x: x is not None, layer)]
+        instructions = list(filter(lambda x: x is not None, layer))
         longest = max([instruction.length for instruction in instructions])
         for instruction in instructions:
             instruction.layer_width = longest

test/python/circuit/test_parameters.py

@@ -356,7 +356,7 @@ class TestParameters(QiskitTestCase):
                       for i in range(num_processes)]
 
         results = parallel_map(_construct_circuit,
-                               [(param) for param in parameters],
+                               parameters,
                                task_args=(qr,),
                                num_processes=num_processes)
 

test/python/compiler/test_assembler.py

@@ -582,8 +582,8 @@ class TestPulseAssemblerMissingKwargs(QiskitTestCase):
         self.backend = FakeOpenPulse2Q()
         self.config = self.backend.configuration()
         self.defaults = self.backend.defaults()
-        self.qubit_lo_freq = [freq for freq in self.defaults.qubit_freq_est]
-        self.meas_lo_freq = [freq for freq in self.defaults.meas_freq_est]
+        self.qubit_lo_freq = list(self.defaults.qubit_freq_est)
+        self.meas_lo_freq = list(self.defaults.meas_freq_est)
         self.qubit_lo_range = self.config.qubit_lo_range
         self.meas_lo_range = self.config.meas_lo_range
         self.schedule_los = {pulse.DriveChannel(0): self.qubit_lo_freq[0],

test/python/quantum_info/test_pauli.py

@@ -385,7 +385,7 @@ class TestPauli(QiskitTestCase):
         self.assertEqual(sgn, 1j)
 
         self.log.info("sign product reverse:")
-        p3, sgn = Pauli.sgn_prod(p2, p1)
+        p3, sgn = Pauli.sgn_prod(p2, p1)  # pylint: disable=arguments-out-of-order
         self.log.info("p2: %s", p2.to_label())
         self.log.info("p1: %s", p1.to_label())
         self.log.info("p3: %s", p3.to_label())

test/python/test_dagcircuit.py

@@ -551,7 +551,7 @@ class TestDagOperations(QiskitTestCase):
         self.dag.apply_operation_back(CnotGate(), [self.qubit0, self.qubit2])
         self.dag.apply_operation_back(HGate(), [self.qubit2])
 
-        op_nodes = [node for node in self.dag.topological_op_nodes()]
+        op_nodes = list(self.dag.topological_op_nodes())
         self.dag.remove_op_node(op_nodes[0])
 
         expected = [('h', [self.qubit0]),

test/python/transpiler/test_collect_2q_blocks.py

@@ -49,7 +49,7 @@ class TestCollect2qBlocks(QiskitTestCase):
         qc.cx(qr[0], qr[1])
         dag = circuit_to_dag(qc)
 
-        topo_ops = [i for i in dag.topological_op_nodes()]
+        topo_ops = list(dag.topological_op_nodes())
         block_1 = [topo_ops[1], topo_ops[2]]
         block_2 = [topo_ops[0], topo_ops[3]]