Apply ruff rules UP006 and UP007 (PlasmaPy#2504)

* Apply changes from UP007

* Manually change annotations to | syntax

* Revert to typing.Union syntax

* Add changelog entry

* Annotate ParticleLike & ParticleListLike with TypeAlias

* Minor correction in mypy.ini

* Add type hint

* Follow recommended type hint practices

* Add type: ignore comments

* Update type hint annotation

.github/scripts/authors_in_cff.py

@@ -3,7 +3,6 @@
 import os
 import pathlib
 import sys
-from typing import Optional
 
 import requests
 
@@ -27,7 +26,7 @@ def get_pr_authors() -> set[str]:
     return authors - set(EXCLUDED_USERS)
 
 
-def check_citation_file(authors: set[str]) -> tuple[bool, Optional[str]]:
+def check_citation_file(authors: set[str]) -> tuple[bool, str | None]:
     """Verify that all authors of a PR are included in :file:`CITATION.cff`."""
     with pathlib.Path("CITATION.cff").open() as file:
         contents = file.read()

changelog/2504.trivial.rst

@@ -0,0 +1,3 @@
+Changed type hint annotations to be consistent with :pep:`604`. Type
+unions are now made using the ``|`` operator rather than with
+`typing.Union`.

docs/_cff_to_rst.py

@@ -3,7 +3,6 @@
 reStructuredText-formatted list.
 """
 import pathlib
-from typing import Union
 
 import yaml
 from unidecode import unidecode
@@ -16,7 +15,7 @@
 obsolete_github_usernames = {}
 
 
-def parse_cff(filename: str) -> dict[str, Union[str, list[dict[str, str]]]]:
+def parse_cff(filename: str) -> dict[str, str | list[dict[str, str]]]:
     """
     Parse a :file:`CITATION.cff` file into a dictionary.
 

mypy.ini

@@ -1,5 +1,5 @@
 [mypy]
-python_version = '3.10'
+python_version = 3.10
 mypy_path = ./type_stubs
 exclude = (?x)(
           docs|

plasmapy/analysis/fit_functions.py

@@ -14,7 +14,6 @@
 import warnings
 from abc import ABC, abstractmethod
 from collections import namedtuple
-from typing import Optional
 
 import numpy as np
 from scipy.optimize import curve_fit, fsolve
@@ -36,8 +35,8 @@ class AbstractFitFunction(ABC):
 
     def __init__(
         self,
-        params: Optional[tuple[float, ...]] = None,
-        param_errors: Optional[tuple[float, ...]] = None,
+        params: tuple[float, ...] | None = None,
+        param_errors: tuple[float, ...] | None = None,
     ) -> None:
         """
         Parameters
@@ -225,7 +224,7 @@ def FitParamTuple(self):
         return self._FitParamTuple
 
     @property
-    def params(self) -> Optional[tuple]:
+    def params(self) -> tuple | None:
         """The fitted parameters for the fit function."""
         if self._params is None:
             return self._params
@@ -247,7 +246,7 @@ def params(self, val) -> None:
             )
 
     @property
-    def param_errors(self) -> Optional[tuple]:
+    def param_errors(self) -> tuple | None:
         """The associated errors of the fitted :attr:`params`."""
         if self._param_errors is None:
             return self._param_errors
@@ -801,8 +800,8 @@ class ExponentialPlusLinear(AbstractFitFunction):
 
     def __init__(
         self,
-        params: Optional[tuple[float, ...]] = None,
-        param_errors: Optional[tuple[float, ...]] = None,
+        params: tuple[float, ...] | None = None,
+        param_errors: tuple[float, ...] | None = None,
     ) -> None:
         self._exponential = Exponential()
         self._linear = Linear()
@@ -939,8 +938,8 @@ class ExponentialPlusOffset(AbstractFitFunction):
 
     def __init__(
         self,
-        params: Optional[tuple[float, ...]] = None,
-        param_errors: Optional[tuple[float, ...]] = None,
+        params: tuple[float, ...] | None = None,
+        param_errors: tuple[float, ...] | None = None,
     ) -> None:
         self._explin = ExponentialPlusLinear()
         super().__init__(params=params, param_errors=param_errors)

plasmapy/analysis/swept_langmuir/floating_potential.py

@@ -4,7 +4,7 @@
 
 import numbers
 import warnings
-from typing import NamedTuple, Optional, Union
+from typing import NamedTuple
 
 import numpy as np
 
@@ -21,32 +21,32 @@ class VFExtras(NamedTuple):
     `~plasmapy.analysis.swept_langmuir.floating_potential.find_floating_potential`.
     """
 
-    vf_err: Optional[float]
+    vf_err: float | None
     """
     Alias for field number 0, the error in the calculated floating
     potential from the floating potential curve fit.
     """
 
-    rsq: Optional[float]
+    rsq: float | None
     """
     Alias for field number 1, the r-squared value of the ion-saturation
     curve fit.
     """
 
-    fitted_func: Optional[float]
+    fitted_func: float | None
     """
     Alias for field number 2, the :term:`fit-function` fitted during
     the floating potential curve fit.
     """
 
-    islands: Optional[list[slice]]
+    islands: list[slice] | None
     """
     Alias for field number 3, a list of `slice` objects representing
     the indices of the identified crossing-islands discovered during
     the floating potential curve fit.
     """
 
-    fitted_indices: Optional[slice]
+    fitted_indices: slice | None
     """
     Alias for field number 4, the indices used in the floating potential
     curve fit.
@@ -57,7 +57,7 @@ def find_floating_potential(  # noqa: C901, PLR0912, PLR0915
     voltage: np.ndarray,
     current: np.ndarray,
     threshold: int = 1,
-    min_points: Optional[Union[int, float]] = None,
+    min_points: float | None = None,
     fit_type: str = "exponential",
 ) -> tuple[np.floating, VFExtras]:
     """

plasmapy/analysis/swept_langmuir/ion_saturation_current.py

@@ -5,7 +5,7 @@
 __aliases__ = ["find_isat_"]
 
 import numbers
-from typing import Any, NamedTuple, Optional
+from typing import Any, NamedTuple
 
 import numpy as np
 
@@ -21,19 +21,19 @@ class ISatExtras(NamedTuple):
     `~plasmapy.analysis.swept_langmuir.ion_saturation_current.find_ion_saturation_current`.
     """
 
-    rsq: Optional[float]
+    rsq: float | None
     """
     Alias for field number 0, the r-squared value of the ion-saturation
     curve fit.
     """
 
-    fitted_func: Optional[ffuncs.AbstractFitFunction]
+    fitted_func: ffuncs.AbstractFitFunction | None
     """
     Alias for field number 1, the :term:`fit-function` fitted during
     the ion-saturation curve fit.
     """
 
-    fitted_indices: Optional[slice]
+    fitted_indices: slice | None
     """
     Alias for field number 2, the indices used in the ion-saturation
     curve fit.
@@ -45,8 +45,8 @@ def find_ion_saturation_current(
     current: np.ndarray,
     *,
     fit_type: str = "exp_plus_linear",
-    current_bound: Optional[numbers.Real] = None,
-    voltage_bound: Optional[numbers.Real] = None,
+    current_bound: numbers.Real | None = None,
+    voltage_bound: numbers.Real | None = None,
 ) -> tuple[ffuncs.Linear, ISatExtras]:
     """
     Determines the ion-saturation current (:math:`I_{sat}`) for a given

plasmapy/diagnostics/charged_particle_radiography/detector_stacks.py

@@ -8,7 +8,6 @@
     "Layer",
 ]
 
-from typing import Optional
 
 import astropy.units as u
 import numpy as np
@@ -62,7 +61,7 @@ def __init__(
         thickness: u.Quantity[u.m],
         energy_axis: u.Quantity[u.J],
         stopping_power: u.Quantity[u.J / u.m, u.J * u.m**2 / u.kg],
-        mass_density: Optional[u.Quantity[u.kg / u.m**3]] = None,
+        mass_density: u.Quantity[u.kg / u.m**3] | None = None,
         active: bool = True,
         name: str = "",
     ) -> None:

plasmapy/diagnostics/charged_particle_radiography/synthetic_radiography.py

@@ -11,7 +11,6 @@
 import sys
 import warnings
 from collections.abc import Iterable
-from typing import Union
 
 import astropy.constants as const
 import astropy.units as u
@@ -125,7 +124,7 @@ class Tracker:
 
     def __init__(
         self,
-        grids: Union[AbstractGrid, Iterable[AbstractGrid]],
+        grids: AbstractGrid | Iterable[AbstractGrid],
         source: u.Quantity[u.m],
         detector: u.Quantity[u.m],
         detector_hdir=None,

plasmapy/diagnostics/charged_particle_radiography/tests/test_synthetic_radiography.py

@@ -2,7 +2,6 @@
 Tests for proton radiography functions
 """
 
-from typing import Optional
 
 import astropy.units as u
 import numpy as np
@@ -22,8 +21,8 @@ def _test_grid(  # noqa: C901, PLR0912
     B0: u.Quantity[u.T] = 10 * u.T,
     E0: u.Quantity[u.V / u.m] = 5e8 * u.V / u.m,
     phi0: u.Quantity[u.V] = 1.4e5 * u.V,
-    a: Optional[u.Quantity[u.m]] = None,
-    b: Optional[u.Quantity[u.m]] = None,
+    a: u.Quantity[u.m] | None = None,
+    b: u.Quantity[u.m] | None = None,
 ):
     r"""
     Generates grids representing some common physical scenarios for testing

plasmapy/diagnostics/thomson.py

@@ -12,7 +12,7 @@
 import numbers
 import warnings
 from collections.abc import Callable
-from typing import Any, Optional, Union
+from typing import Any
 
 import astropy.constants as const
 import astropy.units as u
@@ -63,9 +63,9 @@ def spectral_density_lite(
     ion_vel: np.ndarray,
     probe_vec: np.ndarray,
     scatter_vec: np.ndarray,
-    instr_func_arr: Optional[np.ndarray] = None,
-    notch: Optional[np.ndarray] = None,
-) -> tuple[Union[np.floating, np.ndarray], np.ndarray]:
+    instr_func_arr: np.ndarray | None = None,
+    notch: np.ndarray | None = None,
+) -> tuple[np.floating | np.ndarray, np.ndarray]:
     r"""
     The :term:`lite-function` version of
     `~plasmapy.diagnostics.thomson.spectral_density`.  Performs the same
@@ -297,9 +297,9 @@ def spectral_density(  # noqa: C901, PLR0912, PLR0915
     ion_vel: u.Quantity[u.m / u.s] = None,
     probe_vec=None,
     scatter_vec=None,
-    instr_func: Optional[Callable] = None,
+    instr_func: Callable | None = None,
     notch: u.m = None,
-) -> tuple[Union[np.floating, np.ndarray], np.ndarray]:
+) -> tuple[np.floating | np.ndarray, np.ndarray]:
     r"""Calculate the spectral density function for Thomson scattering of
     a probe laser beam by a multi-species Maxwellian plasma.
 

plasmapy/dispersion/analytical/mhd_waves_.py

@@ -13,7 +13,6 @@
 from abc import ABC, abstractmethod
 from collections import namedtuple
 from numbers import Integral, Real
-from typing import Optional
 
 import astropy.units as u
 import numpy as np
@@ -44,8 +43,8 @@ def __init__(
         *,
         T: u.Quantity[u.K] = 0 * u.K,
         gamma: float = 5 / 3,
-        mass_numb: Optional[Integral] = None,
-        Z: Optional[Real] = None,
+        mass_numb: Integral | None = None,
+        Z: Real | None = None,
     ) -> None:
         # validate arguments
         for arg_name in ("B", "density", "T"):

plasmapy/dispersion/analytical/two_fluid_.py

@@ -6,7 +6,6 @@
 
 import warnings
 from numbers import Integral, Real
-from typing import Optional
 
 import astropy.units as u
 import numpy as np
@@ -37,8 +36,8 @@ def two_fluid(
     T_i: u.Quantity[u.K],
     gamma_e: Real = 1,
     gamma_i: Real = 3,
-    mass_numb: Optional[Integral] = None,
-    Z: Optional[Real] = None,
+    mass_numb: Integral | None = None,
+    Z: Real | None = None,
 ):
     r"""
     Using the solution provided by :cite:t:`bellan:2012`, calculate the

plasmapy/dispersion/dispersion_functions.py

@@ -6,16 +6,15 @@
 
 
 from numbers import Complex
-from typing import Union
 
 import astropy.units as u
 import numpy as np
 from scipy.special import wofz as faddeeva_function
 
 
 def plasma_dispersion_func(
-    zeta: Union[Complex, np.ndarray, u.Quantity[u.dimensionless_unscaled]],
-) -> Union[Complex, np.ndarray, u.Quantity[u.dimensionless_unscaled]]:
+    zeta: Complex | np.ndarray | u.Quantity[u.dimensionless_unscaled],
+) -> Complex | np.ndarray | u.Quantity[u.dimensionless_unscaled]:
     r"""
     Calculate the plasma dispersion function.
 
@@ -80,8 +79,8 @@ def plasma_dispersion_func(
 
 
 def plasma_dispersion_func_deriv(
-    zeta: Union[Complex, np.ndarray, u.Quantity[u.dimensionless_unscaled]],
-) -> Union[Complex, np.ndarray, u.Quantity[u.dimensionless_unscaled]]:
+    zeta: Complex | np.ndarray | u.Quantity[u.dimensionless_unscaled],
+) -> Complex | np.ndarray | u.Quantity[u.dimensionless_unscaled]:
     r"""
     Calculate the derivative of the plasma dispersion function.
 

plasmapy/dispersion/dispersionfunction.py

@@ -11,7 +11,6 @@
 __all__ = ["plasma_dispersion_func", "plasma_dispersion_func_deriv"]
 
 import warnings
-from typing import Union
 
 import astropy.units as u
 import numpy as np
@@ -49,8 +48,8 @@ def plasma_dispersion_func_lite(zeta):
 
 @bind_lite_func(plasma_dispersion_func_lite)
 def plasma_dispersion_func(
-    zeta: Union[complex, np.ndarray, u.Quantity],
-) -> Union[complex, np.ndarray, u.Quantity]:
+    zeta: complex | np.ndarray | u.Quantity,
+) -> complex | np.ndarray | u.Quantity:
     r"""
     Calculate the plasma dispersion function.
 
@@ -100,8 +99,8 @@ def plasma_dispersion_func_deriv_lite(zeta):
 
 @bind_lite_func(plasma_dispersion_func_deriv_lite)
 def plasma_dispersion_func_deriv(
-    zeta: Union[complex, np.ndarray, u.Quantity],
-) -> Union[complex, np.ndarray, u.Quantity]:
+    zeta: complex | np.ndarray | u.Quantity,
+) -> complex | np.ndarray | u.Quantity:
     r"""
     Calculate the derivative of the plasma dispersion function.