Pivot to using ruff for all linting

CONTRIBUTING.md

@@ -764,26 +764,18 @@ int test_FILE_NAME()
 Qiskit uses three tools for Python code formatting and lint checking. The
 first tool is [black](https://github.com/psf/black) which is a code formatting
 tool that will automatically update the code formatting to a consistent style.
-The second tool is [pylint](https://www.pylint.org/) which is a code linter
+The second tool is [ruff](https://docs.astral.sh/ruff/) which is a code linter
 which does a deeper analysis of the Python code to find both style issues and
-potential bugs and other common issues in Python. The third tool is the linter
-[ruff](https://github.com/charliermarsh/ruff), which has been recently
-introduced into Qiskit on an experimental basis. Only a very small number
-of rules are enabled.
+potential bugs and other common issues in Python.
 
 You can check that your local modifications conform to the style rules by
-running `tox -elint` which will run `black`, `ruff`, and `pylint` to check the
+running `tox -elint` which will run `black` and  `ruff` to check the
 local code formatting and lint. If black returns a code formatting error you can
 run `tox -eblack` to automatically update the code formatting to conform to the
-style. However, if `ruff` or `pylint` return any error you will have to fix
-these issues by manually updating your code.
-
-Because `pylint` analysis can be slow, there is also a `tox -elint-incr` target,
-which runs `black` and `ruff` just as `tox -elint` does, but only applies
-`pylint` to files which have changed from the source github. On rare occasions
-this will miss some issues that would have been caught by checking the complete
-source tree, but makes up for this by being much faster (and those rare
-oversights will still be caught by the CI after you open a pull request).
+style. However, if `ruff`  return any error you will have to fix these issues by
+manually updating your code. Sometimes `ruff` will be able to fix failures with
+the `--fix` flag. In these cases the output will tell you how many errors can be
+automatically fixed
 
 Because they are so fast, it is sometimes convenient to run the tools `black` and `ruff` separately
 rather than via `tox`. If you have installed the development packages in your python environment via

Makefile

@@ -16,7 +16,7 @@ endif
 
 .PHONY: default ruff env lint lint-incr style black test test_randomized pytest pytest_randomized test_ci coverage coverage_erase clean cheader clib ctest cformat fix_cformat cclean
 
-default: ruff style lint-incr test ;
+default: style lint-incr test ;
 
 # Dependencies need to be installed on the Anaconda virtual environment.
 env:
@@ -27,18 +27,15 @@ env:
 		bash -c "source activate Qiskitenv;pip install -r requirements.txt"; \
 	fi;
 
-# Ignoring generated ones with .py extension.
 lint:
-	pylint -rn qiskit test tools
+	ruff check qiskit test tools setup.py
 	tools/verify_headers.py qiskit test tools
 	tools/find_optional_imports.py
 	tools/find_stray_release_notes.py
 	tools/verify_images.py
 
-# Only pylint on files that have changed from origin/main. Also parallelize (disables cyclic-import check)
 lint-incr:
-	-git fetch -q https://github.com/Qiskit/qiskit-terra.git :lint_incr_latest
-	tools/pylint_incr.py -j4 -rn -sn --paths :/qiskit/*.py :/test/*.py :/tools/*.py
+	ruff check qiskit test tools setup.py
 	tools/verify_headers.py qiskit test tools
 	tools/find_optional_imports.py
 	tools/verify_images.py

pyproject.toml

@@ -221,18 +221,62 @@ test-command = "cp -r {project}/test . && stestr --test-path test/python run --a
 repair-wheel-command = "cp {wheel} {dest_dir}/. && pipx run abi3audit --strict --report {wheel}"
 
 [tool.ruff]
+line-length = 110
+
+[tool.ruff.lint]
 select = [
-  # Rules in alphabetic order
-  "C4",    # category: flake8-comprehensions
-  "EXE",   # Category: flake8-executable
-  "F631",  # assert-tuple
-  "F632",  # is-literal
-  "F634",  # if-tuple
-  "F823",  # undefined-local
-  "G",     # flake8-logging-format
-  "T10",   # category: flake8-debugger
+    # pycodestyle
+    "E",
+    # Pyflakes
+    "F",
+    # Pylint
+    "PL",
+    # pyupgrade
+    "UP",
+    # bandit
+    "S",
+    # Ruff native rules
+    "RUF",
+]
+ignore = [
+    "E402",  # module-import-not-at-top-of-file false positives with module docs
+    "F401",  # unused-import false triggers on init re-exports with __all__
+    "E501",  # line-too-long rely on black for formatting
+    "PLR2004",  # magic-value-comparison overly pedantic especially in tests
+    "PLR0911",  # too-many-return-statements
+    "PLR0912",  # too-many-branches
+    "PLR0904",  # too-many-public-methods
+    "PLR0914",  # too-many-locals
+    "PLR0915",  # too-many-statements
+    "PLR1702",  # too-many-nested-blocks
+    "PLR0904",  # too-many-public-methods
+    "PLC0415",  # import-outside-top-level
+    "E731",     # lambda-assignment
+    "PLW1514",  # unspecified-encoding do not want to implement
+    "PLR0913",  # too-many-arguments
+    "PLW1641",  # eq-without-hash  not everything has to be hashablie
+    "PLW3301",  # nested-min-max
+    "PLW2901",  # redefined-loop-variablke - TODO fix this
+    "RUF003",   # ambiguous-unicode-character-comment
+    "RUF005",   # collection-literal-concatenation
+    "RUF012",   # mutable-class-default"
+    "RUF001",   # ambiguous-unicode-character-string
+    "RUF002",   # ambiguous-unicode-character-docstring
+    "RUF007",   # zip-instead-of-pairwise overly opinionated
 ]
 
+[tool.ruff.lint.per-file-ignores]
+"*.ipynb" = ["F821"]
+# Security rules from bandit don't apply to tests and utils
+"tools/*" = ["S603"]
+"test/*" = ["S110", "S301", "S603", "S311", "S307", "RUF015"]
+"test/randomized/*" = ["S101"]
+"test/qpy_compat/*" = ["S101"]
+"test/benchmarks/*" = ["S101"]
+# Visualization functions often subprocess to visualization tools
+"qiskit/visualization/*" = ["S603", "S607"]
+
+
 [tool.pylint.main]
 extension-pkg-allow-list = [
     "numpy",
@@ -263,22 +307,19 @@ disable = [
     "protected-access", # disabled as we don't follow the public vs private convention strictly
     "duplicate-code", # disabled as it is too verbose
     "redundant-returns-doc", # for @abstractmethod, it cannot interpret "pass"
-    "too-many-lines", "too-many-branches", "too-many-locals", "too-many-nested-blocks", "too-many-statements",
-    "too-many-instance-attributes", "too-many-arguments", "too-many-public-methods", "too-few-public-methods", "too-many-ancestors",
+    "too-many-instance-attributes", "too-many-arguments", "too-few-public-methods", "too-many-ancestors",
     "unnecessary-pass", # allow for methods with just "pass", for clarity
     "unnecessary-dunder-call", # do not want to implement
     "no-else-return",  # relax "elif" after a clause with a return
     "docstring-first-line-empty", # relax docstring style
     "import-outside-toplevel", "import-error", # overzealous with our optionals/dynamic packages
-    "nested-min-max", # this gives false equivalencies if implemented for the current lint version
     "consider-using-max-builtin", "consider-using-min-builtin",  # unnecessary stylistic opinion
 # TODO(#9614): these were added in modern Pylint. Decide if we want to enable them. If so,
 #  remove from here and fix the issues. Else, move it above this section and add a comment
 #  with the rationale
     "no-member",  # for dynamically created members
     "not-context-manager",
     "unnecessary-lambda-assignment",  # do not want to implement
-    "unspecified-encoding",  # do not want to implement
 ]
 
 enable = [

qiskit/__init__.py

@@ -10,7 +10,6 @@
 # copyright notice, and modified files need to carry a notice indicating
 # that they have been altered from the originals.
 
-# pylint: disable=wrong-import-position,wrong-import-order
 
 """Main Qiskit public functionality."""
 
@@ -31,7 +30,7 @@
     # `qiskit/tools` folder in their path, which will appear as a "namespace package" with no valid
     # location.  We catch that case as "not actually having Qiskit 0.x" as a convenience to devs.
     _has_tools = getattr(importlib.util.find_spec("qiskit.tools"), "has_location", False)
-    _suppress_error = os.environ.get("QISKIT_SUPPRESS_1_0_IMPORT_ERROR", False) == "1"
+    _suppress_error = os.environ.get("QISKIT_SUPPRESS_1_0_IMPORT_ERROR", "") == "1"
     if not _suppress_error and _has_tools:
         raise ImportError(
             "Qiskit is installed in an invalid environment that has both Qiskit >=1.0"
@@ -165,6 +164,6 @@
     "QiskitError",
     "QuantumCircuit",
     "QuantumRegister",
-    "transpile",
     "generate_preset_pass_manager",
+    "transpile",
 ]

qiskit/_numpy_compat.py

@@ -53,7 +53,7 @@
 """
 
 VERSION = np.lib.NumpyVersion(np.__version__)
-VERSION_PARTS: typing.Tuple[int, ...]
+VERSION_PARTS: tuple[int, ...]
 """The numeric parts of the Numpy release version, e.g. ``(2, 0, 0)``.  Does not include pre- or
 post-release markers (e.g. ``rc1``)."""
 if match := re.fullmatch(_VERSION_PATTERN, np.__version__, flags=re.VERBOSE | re.IGNORECASE):

qiskit/circuit/__init__.py

@@ -1374,7 +1374,7 @@ def __array__(self, dtype=None, copy=None):
         \end{pmatrix}
 """
 
-from qiskit._accelerate.circuit import (  # pylint: disable=unused-import
+from qiskit._accelerate.circuit import (
     Bit,
     Qubit,
     AncillaQubit,
@@ -1391,7 +1391,7 @@ def __array__(self, dtype=None, copy=None):
 from .quantumcircuit import QuantumCircuit
 from .gate import Gate
 
-# pylint: disable=cyclic-import
+
 from . import annotation
 from .annotation import Annotation
 from .controlledgate import ControlledGate

qiskit/circuit/_add_control.py

@@ -127,7 +127,6 @@ def control(
         CircuitError: gate contains non-gate in definition
     """
 
-    # pylint: disable=cyclic-import
     from qiskit.circuit import controlledgate
 
     ctrl_state = _ctrl_state_to_int(ctrl_state, num_ctrl_qubits)
@@ -262,23 +261,22 @@ def apply_basic_controlled_gate(circuit, gate, controls, target):
                 circuit.cp(lamb, controls[0], target)
             else:
                 circuit.cu(theta, phi, lamb, 0, controls[0], target)
+        elif phi == -pi / 2 and lamb == pi / 2:
+            circuit.mcrx(theta, controls, target, use_basis_gates=False)
+        elif phi == 0 and lamb == 0:
+            circuit.mcry(
+                theta,
+                controls,
+                target,
+                use_basis_gates=False,
+            )
+        elif theta == 0 and phi == 0:
+            circuit.mcp(lamb, controls, target)
         else:
-            if phi == -pi / 2 and lamb == pi / 2:
-                circuit.mcrx(theta, controls, target, use_basis_gates=False)
-            elif phi == 0 and lamb == 0:
-                circuit.mcry(
-                    theta,
-                    controls,
-                    target,
-                    use_basis_gates=False,
-                )
-            elif theta == 0 and phi == 0:
-                circuit.mcp(lamb, controls, target)
-            else:
-                circuit.mcrz(lamb, controls, target, use_basis_gates=False)
-                circuit.mcry(theta, controls, target, use_basis_gates=False)
-                circuit.mcrz(phi, controls, target, use_basis_gates=False)
-                circuit.mcp((phi + lamb) / 2, controls[1:], controls[0])
+            circuit.mcrz(lamb, controls, target, use_basis_gates=False)
+            circuit.mcry(theta, controls, target, use_basis_gates=False)
+            circuit.mcrz(phi, controls, target, use_basis_gates=False)
+            circuit.mcp((phi + lamb) / 2, controls[1:], controls[0])
 
     elif gate.name == "z":
         circuit.h(target)

qiskit/circuit/_classical_resource_map.py

@@ -16,7 +16,7 @@
 
 import typing
 
-from . import Bit, Clbit, ClassicalRegister  # pylint: disable=cyclic-import
+from . import Bit, Clbit, ClassicalRegister
 from .classical import expr
 
 
@@ -38,9 +38,8 @@ class VariableMapper(expr.ExprVisitor[expr.Expr]):
 
     # We don't want docstrings for the inherited visitor methods, which are self-explanatory and
     # would just be noise.
-    # pylint: disable=missing-function-docstring
 
-    __slots__ = ("target_cregs", "register_map", "bit_map", "var_map", "add_register")
+    __slots__ = ("add_register", "bit_map", "register_map", "target_cregs", "var_map")
 
     def __init__(
         self,

qiskit/circuit/_utils.py

@@ -82,7 +82,8 @@ def _ctrl_state_to_int(ctrl_state, num_ctrl_qubits):
     ctrl_state_std = None
     if isinstance(ctrl_state, str):
         try:
-            assert len(ctrl_state) == num_ctrl_qubits
+            if len(ctrl_state) != num_ctrl_qubits:
+                CircuitError("Invalid number of ctrl qubits for given ctrl state")
             ctrl_state = int(ctrl_state, 2)
         except ValueError as ex:
             raise CircuitError("invalid control bit string: " + ctrl_state) from ex
@@ -96,7 +97,7 @@ def _ctrl_state_to_int(ctrl_state, num_ctrl_qubits):
     elif ctrl_state is None:
         ctrl_state_std = 2**num_ctrl_qubits - 1
     else:
-        raise CircuitError(f"invalid control state specification: {repr(ctrl_state)}")
+        raise CircuitError(f"invalid control state specification: {ctrl_state!r}")
     return ctrl_state_std
 
 

qiskit/circuit/annotated_operation.py

@@ -15,7 +15,7 @@
 from __future__ import annotations
 
 import dataclasses
-from typing import Union, List
+from typing import Union
 
 from qiskit.circuit.operation import Operation
 from qiskit.circuit.parameterexpression import ParameterValueType
@@ -60,7 +60,7 @@ class PowerModifier(Modifier):
 class AnnotatedOperation(Operation):
     """Annotated operation."""
 
-    def __init__(self, base_op: Operation, modifiers: Union[Modifier, List[Modifier]]):
+    def __init__(self, base_op: Operation, modifiers: Modifier | list[Modifier]):
         """
         Create a new AnnotatedOperation.
 
@@ -99,7 +99,7 @@ def __init__(self, base_op: Operation, modifiers: Union[Modifier, List[Modifier]
         """
         self.base_op = base_op
         """The base operation that the modifiers in this annotated operation applies to."""
-        self.modifiers = modifiers if isinstance(modifiers, List) else [modifiers]
+        self.modifiers = modifiers if isinstance(modifiers, list) else [modifiers]
         """Ordered sequence of the modifiers to apply to :attr:`base_op`.  The modifiers are applied
         in order from lowest index to highest index."""
 
@@ -131,13 +131,13 @@ def __eq__(self, other) -> bool:
             and self.base_op == other.base_op
         )
 
-    def copy(self) -> "AnnotatedOperation":
+    def copy(self) -> AnnotatedOperation:
         """Return a copy of the :class:`~.AnnotatedOperation`."""
         return AnnotatedOperation(base_op=self.base_op.copy(), modifiers=self.modifiers.copy())
 
     def to_matrix(self):
         """Return a matrix representation (allowing to construct Operator)."""
-        from qiskit.quantum_info.operators import Operator  # pylint: disable=cyclic-import
+        from qiskit.quantum_info.operators import Operator
 
         operator = Operator(self.base_op)
 
@@ -178,7 +178,7 @@ def control(
         Returns:
             A controlled version of the given operation.
         """
-        # pylint: disable=unused-argument
+
         extended_modifiers = self.modifiers.copy()
         extended_modifiers.append(
             ControlModifier(num_ctrl_qubits=num_ctrl_qubits, ctrl_state=ctrl_state)
@@ -197,7 +197,7 @@ def inverse(self, annotated: bool = True):
         Returns:
             Inverse version of the given operation.
         """
-        # pylint: disable=unused-argument
+
         extended_modifiers = self.modifiers.copy()
         extended_modifiers.append(InverseModifier())
         return AnnotatedOperation(self.base_op, extended_modifiers)
@@ -215,7 +215,7 @@ def power(self, exponent: float, annotated: bool = False):
         Returns:
             An operation implementing ``gate^exponent``
         """
-        # pylint: disable=unused-argument
+
         extended_modifiers = self.modifiers.copy()
         extended_modifiers.append(PowerModifier(exponent))
         return AnnotatedOperation(self.base_op, extended_modifiers)

qiskit/circuit/annotation.py

@@ -189,16 +189,17 @@ def load(self, namespace, payload):
 from __future__ import annotations
 
 import abc
-from typing import Literal, Iterator
+from typing import Literal
+from collections.abc import Iterator
 
 from qiskit._accelerate.circuit import Annotation
 
 
 __all__ = [
     "Annotation",  # Also exported in `qiskit.circuit`, but for convenience is here too.
-    "QPYSerializer",
     "OpenQASM3Serializer",
     "QPYFromOpenQASM3Serializer",
+    "QPYSerializer",
     "iter_namespaces",
 ]
 
@@ -327,7 +328,7 @@ def dump_state(self) -> bytes:
         """
         return b""
 
-    def load_state(self, namespace: str, payload: bytes):  # pylint: disable=unused-argument
+    def load_state(self, namespace: str, payload: bytes):
         """Initialize the state of the deserializer for a given ``namespace`` key.
 
         When in a QPY loading context, this method will be called exactly once, before all calls to