From 3e79bf1f3f4afbe3c6dc8141c3d305fbb0bf31c3 Mon Sep 17 00:00:00 2001
From: Bill Little <bill.james.little@gmail.com>
Date: Wed, 22 Nov 2023 23:57:52 +0000
Subject: [PATCH] enforce all ruff rules (#531)

---
 .ruff.toml                                    | 45 +++++++++++
 MANIFEST.in                                   |  1 +
 pyproject.toml                                | 56 ++++++++++----
 setup.py                                      |  0
 src/geovista/bridge.py                        | 12 +--
 src/geovista/cache.py                         |  4 +-
 src/geovista/cli.py                           |  6 +-
 src/geovista/common.py                        | 61 +++++++--------
 src/geovista/core.py                          | 43 ++++++-----
 src/geovista/crs.py                           | 19 +++--
 src/geovista/examples/clouds.py               |  2 +-
 src/geovista/examples/clouds_robin.py         |  2 +-
 src/geovista/examples/earthquakes.py          |  2 +-
 src/geovista/examples/earthquakes_wink1.py    |  2 +-
 src/geovista/examples/from_1d__oisst.py       |  2 +-
 src/geovista/examples/from_1d__oisst_eqc.py   |  2 +-
 .../examples/from_1d__synthetic_face_m1_n1.py |  2 +-
 .../from_1d__synthetic_face_m1_n1_robin.py    |  2 +-
 .../examples/from_1d__synthetic_node_m1_n1.py |  2 +-
 .../from_1d__synthetic_node_m1_n1_moll.py     |  2 +-
 src/geovista/examples/from_2d__orca.py        |  2 +-
 src/geovista/examples/from_2d__orca_moll.py   |  2 +-
 .../examples/from_2d__synthetic_face_m1n1.py  |  2 +-
 .../from_2d__synthetic_face_m1n1_robin.py     |  2 +-
 .../examples/from_2d__synthetic_node_m1n1.py  |  2 +-
 .../from_2d__synthetic_node_m1n1_moll.py      |  2 +-
 .../examples/from_points__orca_cloud.py       |  3 +-
 .../examples/from_points__orca_cloud_eqc.py   |  3 +-
 .../examples/from_unstructured__fesom.py      |  2 +-
 .../examples/from_unstructured__fesom_fouc.py |  2 +-
 .../examples/from_unstructured__fvcom.py      |  2 +-
 .../examples/from_unstructured__icon.py       |  2 +-
 .../examples/from_unstructured__icon_eqc.py   |  2 +-
 .../from_unstructured__icosahedral.py         |  2 +-
 .../from_unstructured__icosahedral_poly.py    |  2 +-
 .../from_unstructured__lam_pacific.py         |  2 +-
 .../from_unstructured__lam_pacific_moll.py    |  2 +-
 .../examples/from_unstructured__lfric_orog.py |  2 +-
 .../from_unstructured__lfric_orog_warp.py     |  2 +-
 .../examples/from_unstructured__lfric_sst.py  |  2 +-
 .../from_unstructured__lfric_sst_bonne.py     |  2 +-
 .../examples/from_unstructured__smc.py        |  2 +-
 .../examples/from_unstructured__smc_sinu.py   |  2 +-
 .../examples/from_unstructured__tri.py        |  2 +-
 .../examples/from_unstructured__tri_hammer.py |  2 +-
 src/geovista/examples/uber_h3.py              | 17 ++---
 src/geovista/examples/vectors.py              |  2 +-
 src/geovista/geodesic.py                      | 67 ++++++++---------
 src/geovista/geometry.py                      |  8 +-
 src/geovista/geoplotter.py                    | 34 ++++-----
 src/geovista/gridlines.py                     | 39 +++++-----
 src/geovista/pantry.py                        | 75 ++++++-------------
 src/geovista/report.py                        |  4 +-
 src/geovista/samples.py                       | 51 ++++---------
 src/geovista/search.py                        | 24 +++---
 src/geovista/transform.py                     | 23 +++---
 tests/bridge/test__as_compatible_data.py      |  2 +-
 tests/common/conftest.py                      |  4 +-
 tests/common/test_Preference.py               |  2 +-
 tests/common/test_distance.py                 | 12 ++-
 tests/common/test_from_cartesian.py           | 14 ++--
 tests/common/test_nan_mask.py                 |  2 +-
 tests/common/test_sanitize_data.py            |  6 +-
 tests/common/test_to_cartesian.py             |  6 +-
 tests/common/test_to_lonlat.py                |  2 +-
 tests/common/test_to_lonlats.py               |  2 +-
 tests/common/test_wrap.py                     |  3 +-
 tests/conftest.py                             | 20 ++---
 tests/core/test_slice_lines.py                | 18 ++---
 tests/crs/test_has_wkt.py                     |  2 +-
 tests/geodesic/conftest.py                    |  2 +-
 tests/geodesic/test_Preference.py             |  2 +-
 tests/geodesic/test_line.py                   | 10 +--
 tests/geoplotter/test_add_points.py           |  4 +-
 tests/gridlines/test__step_period.py          | 22 +++---
 .../gridlines/test_create_meridian_labels.py  | 34 ++++-----
 tests/gridlines/test_create_meridians.py      |  4 +-
 .../gridlines/test_create_parallel_labels.py  | 46 ++++++------
 tests/gridlines/test_create_parallels.py      |  4 +-
 tests/plotting/test_examples.py               |  2 +-
 tests/search/conftest.py                      | 38 ++++++++--
 tests/search/test_Preference.py               |  2 +-
 tests/search/test_find_nearest_cell.py        |  4 +-
 tests/transform/test_transform_points.py      |  6 +-
 84 files changed, 502 insertions(+), 436 deletions(-)
 create mode 100644 .ruff.toml
 mode change 100644 => 100755 setup.py

diff --git a/.ruff.toml b/.ruff.toml
new file mode 100644
index 00000000..4e1446e5
--- /dev/null
+++ b/.ruff.toml
@@ -0,0 +1,45 @@
+extend = "pyproject.toml"
+
+lint.ignore = [
+    # NOTE: To find a rule code to fix, run:
+    #       ruff --select="ALL" --statistics src/geovista/<subpackage>
+
+    # flake8-boolean-trap (FBT)
+    # NOTE: A good thing to fix, but changes API.
+    "FBT001",  # boolean-positional-arg-in-function-definition.
+    "FBT002",  # boolean-default-value-in-function-definition.
+    "FBT003",  # boolean-positional-value-in-function-call.
+
+    # Pylint (PL)
+    "PLR0912",  # Too many branches.
+    "PLR0913",  # Too many arguments in function definition.
+    "PLR0915",  # Too many statements.
+    "PLR2004",  # Magic value used in comparison, consider replacing with a constant.
+    "PLW0603",  # Using the global statement to update is discouraged.
+
+    # flake8-self (SLF)
+    "SLF001",  # Private member accessed.
+
+    # flake8-todos (TD)
+    "TD003",  # Missing issue link on the line following this TODO.
+]
+
+[lint.extend-per-file-ignores]
+"conftest.py" = [
+    # flake8-annotations (ANN)
+    "ANN001",  # Missing type annotation for function argument.
+    "ANN201",  # Missing return type annotation for public function.
+]
+"src/geovista/geoplotter.py" = [
+    # flake8-annotations (ANN)
+    "ANN401",  # Dynamically typed expressions (typing.Any).
+]
+"test_*.py" = [
+    # flake8-annotations (ANN)
+    "ANN001",  # Missing type annotation for function argument.
+    "ANN201",  # Missing return type annotation for public funciton.
+]
+"test_slice_lines.py" = [
+    # eradicate (ERA)
+    "ERA001",  # Found commented-out code.
+]
diff --git a/MANIFEST.in b/MANIFEST.in
index 41c138c8..3096fe4b 100644
--- a/MANIFEST.in
+++ b/MANIFEST.in
@@ -11,6 +11,7 @@ include .gitattributes
 exclude .gitignore
 exclude .pre-commit-config.yaml
 exclude .readthedocs.yml
+exclude .ruff.toml
 include *.md
 include CITATION.cff
 exclude codecov.yml
diff --git a/pyproject.toml b/pyproject.toml
index e3d899c9..fbd043b7 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -115,17 +115,38 @@ target-version = "py310"
 
 [tool.ruff.lint]
 ignore = [
-    "D105",  # pydocstyle: undocumented-magic-method
+    # NOTE: Non-permanent exclusions should be added to ".ruff.toml".
+
+    # flake8-annotations (ANN)
+    "ANN101",  # Missing type annotation for 'self' in method.
+    "ANN102",  # Missing type annotation for 'cls' in classmethod.
+
+    # flake8-commas (COM)
+    "COM812",  # Trailing comma missing.
+    "COM819",  # Trailing comma prohibited.
+
+    # pydocstyle (D)
+    "D105",  # Missing docstring in magic method.
+
+    # flake8-fixme (FIX)
+    "FIX002",  # Line contains TODO, consider resolving the issue.
+
+    # pep8-naming
+    "N806",  # Variable name in function should be lowercase.
+    "N999",  # Invalid module name.
+
+    # pandas-vet (PD)
+    "PD",
+
+    # Ruff-specific rules (RUF)
+    "RUF005",  # Consider {expression} instead of concatenation.
+
+    # flake8-bandit (S)
+    "S101",  # Use of assert detected.
 ]
+preview = false
 select = [
-    "B",   # flake8-bugbear
-    "C4",  # flake8-comprehensions
-    "I",   # isort
-    "E",   # pycodestyle
-    "W",
-    "D",   # pydocstyle
-    "F",   # pyflakes
-    "UP",  # pyupgrade
+    "ALL",
 ]
 
 
@@ -136,13 +157,22 @@ required-imports = ["from __future__ import annotations"]
 
 
 [tool.ruff.lint.mccabe]
-max-complexity = 22
+max-complexity = 26
 
 
 [tool.ruff.lint.per-file-ignores]
-"src/geovista/examples/earthquakes.py" = ["E501"]
-"src/geovista/examples/earthquakes_wink1.py" = ["E501"]
-"src/geovista/report.py" = ["E722"]
+"src/geovista/cli.py" = [
+    "T201",  # flake8-print: print found.
+]
+"src/geovista/examples/*.py" = [
+    "TCH002",  # flake8-type-checking: Move 3rd-party import into a type checking block.
+]
+"src/geovista/examples/earthquakes.py" = [
+    "E501",  # pycodestyle: Line too long.
+]
+"src/geovista/examples/earthquakes_wink1.py" = [
+    "E501",  # pycodestyle: Line too long.
+]
 
 
 [tool.ruff.lint.pydocstyle]
diff --git a/setup.py b/setup.py
old mode 100644
new mode 100755
diff --git a/src/geovista/bridge.py b/src/geovista/bridge.py
index ce107919..7fe8dd25 100644
--- a/src/geovista/bridge.py
+++ b/src/geovista/bridge.py
@@ -11,11 +11,11 @@
 """
 from __future__ import annotations
 
+from typing import TYPE_CHECKING
 import warnings
 
 import numpy as np
 from numpy import ma
-from numpy.typing import ArrayLike
 from pyproj import CRS
 import pyvista as pv
 
@@ -32,6 +32,9 @@
 from .crs import WGS84, CRSLike, to_wkt
 from .transform import transform_points
 
+if TYPE_CHECKING:
+    from numpy.typing import ArrayLike
+
 __all__ = ["Transform"]
 
 # type aliases
@@ -217,9 +220,7 @@ def _create_connectivity_m1n1(shape: Shape) -> np.ndarray:
         nodes_c2 = np.ravel(idxs[:-1, 1:]).reshape(-1, 1)
         nodes_c3 = np.ravel(idxs[:-1, :-1]).reshape(-1, 1)
 
-        connectivity = np.hstack([nodes_c0, nodes_c1, nodes_c2, nodes_c3])
-
-        return connectivity
+        return np.hstack([nodes_c0, nodes_c1, nodes_c2, nodes_c3])
 
     @staticmethod
     def _create_connectivity_mn4(shape: Shape) -> np.ndarray:
@@ -258,9 +259,8 @@ def _create_connectivity_mn4(shape: Shape) -> np.ndarray:
 
         # we know that we can only be dealing with a quad mesh
         npts = np.prod(shape) * 4
-        connectivity = np.arange(npts, dtype=np.uint32).reshape(-1, 4)
 
-        return connectivity
+        return np.arange(npts, dtype=np.uint32).reshape(-1, 4)
 
     @staticmethod
     def _verify_2d(xs: ArrayLike, ys: ArrayLike) -> None:
diff --git a/src/geovista/cache.py b/src/geovista/cache.py
index efccb8dd..b4df6fb8 100644
--- a/src/geovista/cache.py
+++ b/src/geovista/cache.py
@@ -183,8 +183,8 @@ def fetch_coastlines(resolution: str | None = None) -> pv.PolyData:
     fname = f"ne_coastlines_{resolution}.vtk"
     processor = pooch.Decompress(method="auto", name=fname)
     resource = CACHE.fetch(f"natural_earth/physical/{fname}.bz2", processor=processor)
-    mesh = pv.read(resource)
-    return mesh
+
+    return pv.read(resource)
 
 
 def natural_earth_1(location: bool | None = False) -> TextureLike:
diff --git a/src/geovista/cli.py b/src/geovista/cli.py
index f45f7df5..175dcf22 100644
--- a/src/geovista/cli.py
+++ b/src/geovista/cli.py
@@ -265,7 +265,7 @@ def download(
         previous_path = CACHE.path
         CACHE.path = output
 
-    def collect(prefix):
+    def collect(prefix: str) -> list[str]:
         return list(filter(lambda item: item.startswith(prefix), fnames))
 
     if pull:
@@ -380,7 +380,7 @@ def collect(prefix):
     is_flag=True,
     help="Enable example diagnostics.",
 )
-def examples(run_all, show, run, verbose):
+def examples(run_all: bool, show: bool, run: bool, verbose: bool) -> None:
     """Execute a geovista example script."""
     # account for the initial "all" option
     n_scripts = len(SCRIPTS) - 1
@@ -436,7 +436,7 @@ def examples(run_all, show, run, verbose):
     is_flag=True,
     help="Add a base layer",
 )
-def plot(fname, axes, base) -> None:
+def plot(fname: str, axes: bool, base: bool) -> None:
     """Load and render a VTK mesh."""
     mesh = pv.read(fname)
     plotter = GeoPlotter()
diff --git a/src/geovista/common.py b/src/geovista/common.py
index ec3eb457..78efc22c 100644
--- a/src/geovista/common.py
+++ b/src/geovista/common.py
@@ -10,16 +10,18 @@
 from collections.abc import Iterable
 from enum import Enum
 import sys
-from typing import Any
+from typing import TYPE_CHECKING
 
 import numpy as np
 from numpy import ma
-from numpy.typing import ArrayLike
 import pyvista as pv
 from pyvista import _vtk
 from pyvista.core.filters import _get_output
 from vtk import vtkLogger, vtkObject
 
+if TYPE_CHECKING:
+    from numpy.typing import ArrayLike
+
 __all__ = [
     "BASE",
     "CENTRAL_MERIDIAN",
@@ -60,9 +62,7 @@
     "wrap",
 ]
 
-#
-# TODO: support richer default management
-#
+# TODO @bjlittle: support richer default management
 
 #: Default base for wrapped longitude half-open interval, in degrees.
 BASE: float = -180.0
@@ -214,11 +214,11 @@ def __str__(self) -> str:
         .. versionadded:: 0.3.0
 
         """
-        # TODO: remove when minimum supported python version is 3.11
+        # TODO @bjlittle: Remove when minimum supported python version is 3.11.
         return f"{self.name.lower()}"
 
 
-# TODO: use StrEnum and auto when minimum supported python version is 3.11
+# TODO @bjlittle: Use StrEnum and auto when minimum supported python version is 3.11.
 class Preference(_MixinStrEnum, Enum):
     """Enumeration of common mesh geometry preferences.
 
@@ -257,7 +257,7 @@ def active_kernel() -> bool:
     return result
 
 
-def cast_UnstructuredGrid_to_PolyData(
+def cast_UnstructuredGrid_to_PolyData(  # noqa: N802
     mesh: pv.UnstructuredGrid,
     clean: bool | None = False,
 ) -> pv.PolyData:
@@ -405,22 +405,27 @@ def from_cartesian(
 
     zlevel = np.zeros_like(lons)
 
-    if cloud:
-        if GV_FIELD_RADIUS in mesh.field_data and GV_FIELD_ZSCALE in mesh.field_data:
-            # field data injected by geovista.bridge.Transform.from_points
-            base = mesh[GV_FIELD_RADIUS][0]
-            zscale = mesh[GV_FIELD_ZSCALE][0]
-            zlevel = (radius - base) / (base * zscale)
+    if (
+        cloud
+        and GV_FIELD_RADIUS in mesh.field_data
+        and GV_FIELD_ZSCALE in mesh.field_data
+    ):
+        # field data injected by geovista.bridge.Transform.from_points
+        base = mesh[GV_FIELD_RADIUS][0]
+        zscale = mesh[GV_FIELD_ZSCALE][0]
+        zlevel = (radius - base) / (base * zscale)
 
     data = [lons, lats, zlevel]
 
-    # XXX: manage pole longitudes. an alternative future scheme could be more
-    # generic and inclusive, but this approach tackles the main use case for now
-    # TODO: refactor this into a separate function
+    # TODO @bjlittle: Manage pole longitudes. an alternative future scheme could be
+    #                 more generic and inclusive, but this approach tackles the main
+    #                 use case for now.
+
+    # TODO @bjlittle: Refactor this into a separate function.
     pole_pids = np.where(np.isclose(np.abs(lats), 90))[0]
     if pole_pids.size:
         # enforce a common longitude for pole singularities
-        # TODO: review this strategy
+        # TODO @bjlittle: Review this strategy.
         lons[pole_pids] = 0
 
         if (
@@ -437,7 +442,7 @@ def from_cartesian(
             pole_cids = np.unique(pole_submesh["vtkOriginalCellIds"])
             for cid in pole_cids:
                 # get the pids (point-indices) of the polar cell points
-                # XXX: pyvista 0.38.0: cell_point_ids(cid) -> get_cell(cid).point_ids
+                # NOTE: pyvista 0.38.0: cell_point_ids(cid) -> get_cell(cid).point_ids
                 cell_pids = np.array(mesh.get_cell(cid).point_ids)
                 # unfold polar quad-cells
                 if len(cell_pids) == 4:
@@ -478,7 +483,7 @@ def from_cartesian(
             seam_mask = np.isclose(np.abs(seam_lons), 180)
             lons[seam_ids[seam_mask]] = 180
         elif mesh.n_lines:
-            # TODO: unify closed interval strategies for lines and cells
+            # TODO @bjlittle: Unify closed interval strategies for lines and cells.
             poi_mask = np.isclose(np.abs(lons), 180)
 
             if np.any(poi_mask):
@@ -498,9 +503,7 @@ def from_cartesian(
 
                     lons[pids] = 180
 
-    result = np.vstack(data).T if stacked else np.array(data)
-
-    return result
+    return np.vstack(data).T if stacked else np.array(data)
 
 
 def nan_mask(data: ArrayLike) -> np.ndarray:
@@ -555,7 +558,7 @@ def point_cloud(mesh: pv.PolyData) -> bool:
 
 
 def sanitize_data(
-    *meshes: Any,
+    *meshes: Iterable[pv.PolyData],
 ) -> None:
     """Purge standard VTK helper cell and point data index arrays.
 
@@ -691,9 +694,8 @@ def to_cartesian(
     y = np.ravel(radius * np.sin(y_rad) * np.sin(x_rad))
     z = np.ravel(radius * np.cos(y_rad))
     xyz = [x, y, z]
-    xyz = np.vstack(xyz).T if stacked else np.array(xyz)
 
-    return xyz
+    return np.vstack(xyz).T if stacked else np.array(xyz)
 
 
 def to_lonlat(
@@ -817,8 +819,8 @@ def to_lonlats(
     lons = wrap(lons, base=base, period=period, rtol=rtol, atol=atol)
 
     z_radius = points[:, 2] / radius
-    # XXX: defensive clobber of values outside arcsin domain [-1, 1]
-    # which is the result of floating point inaccuracies at the extremes
+    # NOTE: defensive clobber of values outside arcsin domain [-1, 1]
+    #       which is the result of floating point inaccuracies at the extremes
     if indices := np.where(z_radius > 1):
         z_radius[indices] = 1.0
     if indices := np.where(z_radius < -1):
@@ -828,9 +830,8 @@ def to_lonlats(
         lats = np.degrees(lats)
 
     data = [lons, lats]
-    result = np.vstack(data).T if stacked else np.array(data)
 
-    return result
+    return np.vstack(data).T if stacked else np.array(data)
 
 
 def triangulated(surface: pv.PolyData) -> bool:
diff --git a/src/geovista/core.py b/src/geovista/core.py
index e4c5033d..f8f7e3f8 100644
--- a/src/geovista/core.py
+++ b/src/geovista/core.py
@@ -9,11 +9,10 @@
 
 import copy
 from enum import Enum, auto, unique
-from typing import Any
+from typing import TYPE_CHECKING
 import warnings
 
 import numpy as np
-from numpy.typing import ArrayLike
 import pyvista as pv
 
 from .common import (
@@ -39,6 +38,11 @@
 from .filters import remesh
 from .search import find_cell_neighbours
 
+if TYPE_CHECKING:
+    from collections.abc import Iterable
+
+    from numpy.typing import ArrayLike
+
 __all__ = [
     "MeridianSlice",
     "add_texture_coords",
@@ -176,9 +180,8 @@ def _intersection(
         # the higher the number of spline interpolation "n_points"
         # the more accurate, but the more compute intensive and less performant
         spline = pv.Spline(xyz.points, n_points=n_points)
-        mesh = self.mesh.slice_along_line(spline)
 
-        return mesh
+        return self.mesh.slice_along_line(spline)
 
     def extract(
         self,
@@ -311,7 +314,7 @@ def add_texture_coords(
 
 
 def combine(
-    *meshes: Any,
+    *meshes: Iterable[pv.PolyData],
     data: bool | None = True,
     clean: bool | None = False,
 ) -> pv.PolyData:
@@ -421,7 +424,7 @@ def combine(
     faces = np.hstack(combined_faces)
     combined = pv.PolyData(points, faces=faces, n_faces=n_faces)
 
-    def combine_data(names, field=False):
+    def combine_data(names: set[str], field: bool | None = False) -> None:
         for name in names:
             if field:
                 combined.field_data[name] = first[name]
@@ -634,8 +637,9 @@ def slice_cells(
         if GV_REMESH_POINT_IDS not in result.point_data:
             result.point_data[GV_REMESH_POINT_IDS] = result[GV_POINT_IDS].copy()
 
-        # XXX: defensive removal of cells that span the meridian and should
-        # have been remeshed, but haven't due to their geometry ?
+        # TODO @bjlittle: Investigate defensive removal of cells that span the meridian
+        #                 and should have been remeshed, but haven't due to their
+        #                 geometry ?
         cids = set(find_cell_neighbours(result, remeshed[GV_CELL_IDS]))
         cids = cids.difference(set(remeshed_ids))
         if cids:
@@ -644,7 +648,7 @@ def slice_cells(
             neighbours.points = xy0
             xdelta = []
             for cid in range(neighbours.n_cells):
-                # XXX: pyvista 0.38.0: cell_points(cid) -> get_cell(cid).points
+                # NOTE: pyvista 0.38.0: cell_points(cid) -> get_cell(cid).points
                 cxpts = neighbours.get_cell(cid).points[:, 0]
                 cxmin, cxmax = cxpts.min(), cxpts.max()
                 xdelta.append(cxmax - cxmin)
@@ -664,7 +668,7 @@ def slice_cells(
     if meshes:
         result.remove_cells(np.unique(remeshed_ids), inplace=True)
         # reinstate field data purged by remove_cells
-        for field in mesh.field_data.keys():
+        for field in mesh.field_data:
             result.field_data[field] = copy.deepcopy(mesh.field_data[field])
         result = combine(result, *meshes)
 
@@ -801,18 +805,18 @@ def slice_lines(
         # points and M cells i.e.,
         #        cid                    cid                       cid(new)
         # pid(0) --- pid(1)  =>  pid(0) --- pid(new0) & pid(new1) -------- pid(1)
-        #                             [step1]                     [step2]
+        #                             <step1>                     <step2>
         # where, pid(new0) and pid(new1) are distinct pids but reference identical, but
         # not the same cartesian xyz point
         #
-        # [step1]
+        # <step1>
         n_points = points.shape[0]
         split_points = np.vstack(split_xyz)
         points = np.vstack([points, split_points])  # append M points
         new_pids = np.arange(n_points, points.shape[0])
         split_lines = lines[split_cids]
         lines[split_cids, 2] = new_pids  # inplace M cells
-        # [step2]
+        # <step2>
         n_points = points.shape[0]
         points = np.vstack([points, split_points])  # append M points
         new_pids = np.arange(n_points, points.shape[0])
@@ -824,7 +828,7 @@ def slice_lines(
         # points i.e.,
         #        cid0        cid1                    cid0                   cid1
         # pid(0) ---- pid(1) ---- pid(2)  =>  pid(0) ---- pid(new) & pid(1) ---- pid(2)
-        #                                                                   [nop]
+        #                                                                   <nop>
         # where, pid(new) and pid(1) are distinct pids but reference identical, but not
         # the same cartesian xyz point
         #
@@ -842,7 +846,7 @@ def slice_lines(
         lines[detach_cids, 1:] = line_pids  # inplace M cells
 
     if mesh.field_data.keys():
-        for key in mesh.field_data.keys():
+        for key in mesh.field_data:
             result.field_data[key] = mesh.field_data[key].copy()
 
     # TDB: given mesh.points, perform linear interpolation for new intersection points
@@ -892,10 +896,9 @@ def slice_mesh(
         emsg = "Cannot slice a mesh that has been projected."
         raise ValueError(emsg)
 
-    result = (
-        slice_lines(mesh, copy=True)
-        if mesh.n_lines
-        else slice_cells(mesh, antimeridian=True, rtol=rtol, atol=atol)
-    )
+    if mesh.n_lines:
+        result = slice_lines(mesh, copy=True)
+    else:
+        result = slice_cells(mesh, antimeridian=True, rtol=rtol, atol=atol)
 
     return result
diff --git a/src/geovista/crs.py b/src/geovista/crs.py
index ac55f24b..bfedf9fe 100644
--- a/src/geovista/crs.py
+++ b/src/geovista/crs.py
@@ -7,12 +7,16 @@
 """
 from __future__ import annotations
 
+from typing import TYPE_CHECKING
+
 import numpy as np
 from pyproj import CRS
-import pyvista as pv
 
 from .common import GV_FIELD_CRS
 
+if TYPE_CHECKING:
+    import pyvista as pv
+
 __all__ = [
     "CRSLike",
     "PlateCarree",
@@ -184,12 +188,13 @@ def set_central_meridian(crs: CRS, meridian: float) -> CRS | None:
     result = None
     crs_json = crs.to_json_dict()
     found = False
-    if conversion := crs_json.get("conversion"):
-        if parameters := conversion.get("parameters"):
-            for param in parameters:
-                if found := param["id"]["code"] == int(EPSG_CENTRAL_MERIDIAN):
-                    param["value"] = meridian
-                    break
+    if (conversion := crs_json.get("conversion")) and (
+        parameters := conversion.get("parameters")
+    ):
+        for param in parameters:
+            if found := param["id"]["code"] == int(EPSG_CENTRAL_MERIDIAN):
+                param["value"] = meridian
+                break
     if found:
         result = CRS.from_json_dict(crs_json)
 
diff --git a/src/geovista/examples/clouds.py b/src/geovista/examples/clouds.py
index 345a3457..4c6b15d0 100755
--- a/src/geovista/examples/clouds.py
+++ b/src/geovista/examples/clouds.py
@@ -13,7 +13,7 @@
 
 import geovista as gv
 from geovista.pantry import cloud_amount
-import geovista.theme  # noqa: F401
+import geovista.theme
 
 #: The colormap to render the clouds.
 CMAP = cmocean.cm.gray
diff --git a/src/geovista/examples/clouds_robin.py b/src/geovista/examples/clouds_robin.py
index 8686db08..735cc88d 100755
--- a/src/geovista/examples/clouds_robin.py
+++ b/src/geovista/examples/clouds_robin.py
@@ -13,7 +13,7 @@
 
 import geovista as gv
 from geovista.pantry import cloud_amount
-import geovista.theme  # noqa: F401
+import geovista.theme
 
 #: The colormap to render the clouds.
 CMAP = cmocean.cm.gray
diff --git a/src/geovista/examples/earthquakes.py b/src/geovista/examples/earthquakes.py
index 3df29e36..4f198cff 100755
--- a/src/geovista/examples/earthquakes.py
+++ b/src/geovista/examples/earthquakes.py
@@ -12,7 +12,7 @@
 
 import geovista as gv
 from geovista.pantry import usgs_earthquakes
-import geovista.theme  # noqa: F401
+import geovista.theme
 
 
 def main() -> None:
diff --git a/src/geovista/examples/earthquakes_wink1.py b/src/geovista/examples/earthquakes_wink1.py
index ae065883..594ce457 100755
--- a/src/geovista/examples/earthquakes_wink1.py
+++ b/src/geovista/examples/earthquakes_wink1.py
@@ -12,7 +12,7 @@
 
 import geovista as gv
 from geovista.pantry import usgs_earthquakes
-import geovista.theme  # noqa: F401
+import geovista.theme
 
 
 def main() -> None:
diff --git a/src/geovista/examples/from_1d__oisst.py b/src/geovista/examples/from_1d__oisst.py
index 3aa16129..1b70736b 100755
--- a/src/geovista/examples/from_1d__oisst.py
+++ b/src/geovista/examples/from_1d__oisst.py
@@ -10,7 +10,7 @@
 
 import geovista as gv
 from geovista.pantry import oisst_avhrr_sst
-import geovista.theme  # noqa: F401
+import geovista.theme
 
 
 def main() -> None:
diff --git a/src/geovista/examples/from_1d__oisst_eqc.py b/src/geovista/examples/from_1d__oisst_eqc.py
index 7e5d50b9..c02fe56c 100755
--- a/src/geovista/examples/from_1d__oisst_eqc.py
+++ b/src/geovista/examples/from_1d__oisst_eqc.py
@@ -10,7 +10,7 @@
 
 import geovista as gv
 from geovista.pantry import oisst_avhrr_sst
-import geovista.theme  # noqa: F401
+import geovista.theme
 
 
 def main() -> None:
diff --git a/src/geovista/examples/from_1d__synthetic_face_m1_n1.py b/src/geovista/examples/from_1d__synthetic_face_m1_n1.py
index c571ebf0..c5a4ef68 100755
--- a/src/geovista/examples/from_1d__synthetic_face_m1_n1.py
+++ b/src/geovista/examples/from_1d__synthetic_face_m1_n1.py
@@ -11,7 +11,7 @@
 import numpy as np
 
 import geovista as gv
-import geovista.theme  # noqa: F401
+import geovista.theme
 
 
 def main() -> None:
diff --git a/src/geovista/examples/from_1d__synthetic_face_m1_n1_robin.py b/src/geovista/examples/from_1d__synthetic_face_m1_n1_robin.py
index 1dba41aa..aeb9df1b 100755
--- a/src/geovista/examples/from_1d__synthetic_face_m1_n1_robin.py
+++ b/src/geovista/examples/from_1d__synthetic_face_m1_n1_robin.py
@@ -11,7 +11,7 @@
 import numpy as np
 
 import geovista as gv
-import geovista.theme  # noqa: F401
+import geovista.theme
 
 
 def main() -> None:
diff --git a/src/geovista/examples/from_1d__synthetic_node_m1_n1.py b/src/geovista/examples/from_1d__synthetic_node_m1_n1.py
index a654a8c3..a5b1aec2 100755
--- a/src/geovista/examples/from_1d__synthetic_node_m1_n1.py
+++ b/src/geovista/examples/from_1d__synthetic_node_m1_n1.py
@@ -11,7 +11,7 @@
 import numpy as np
 
 import geovista as gv
-import geovista.theme  # noqa: F401
+import geovista.theme
 
 
 def main() -> None:
diff --git a/src/geovista/examples/from_1d__synthetic_node_m1_n1_moll.py b/src/geovista/examples/from_1d__synthetic_node_m1_n1_moll.py
index ab25a493..4e42b36d 100755
--- a/src/geovista/examples/from_1d__synthetic_node_m1_n1_moll.py
+++ b/src/geovista/examples/from_1d__synthetic_node_m1_n1_moll.py
@@ -11,7 +11,7 @@
 import numpy as np
 
 import geovista as gv
-import geovista.theme  # noqa: F401
+import geovista.theme
 
 
 def main() -> None:
diff --git a/src/geovista/examples/from_2d__orca.py b/src/geovista/examples/from_2d__orca.py
index 55656df4..cbddce70 100755
--- a/src/geovista/examples/from_2d__orca.py
+++ b/src/geovista/examples/from_2d__orca.py
@@ -10,7 +10,7 @@
 
 import geovista as gv
 from geovista.pantry import um_orca2
-import geovista.theme  # noqa: F401
+import geovista.theme
 
 
 def main() -> None:
diff --git a/src/geovista/examples/from_2d__orca_moll.py b/src/geovista/examples/from_2d__orca_moll.py
index 61e88acf..136eb268 100755
--- a/src/geovista/examples/from_2d__orca_moll.py
+++ b/src/geovista/examples/from_2d__orca_moll.py
@@ -13,7 +13,7 @@
 import geovista as gv
 from geovista.common import cast_UnstructuredGrid_to_PolyData as cast
 from geovista.pantry import um_orca2
-import geovista.theme  # noqa: F401
+import geovista.theme
 from geovista.transform import transform_mesh
 
 
diff --git a/src/geovista/examples/from_2d__synthetic_face_m1n1.py b/src/geovista/examples/from_2d__synthetic_face_m1n1.py
index 4cfe4e09..f61857ed 100755
--- a/src/geovista/examples/from_2d__synthetic_face_m1n1.py
+++ b/src/geovista/examples/from_2d__synthetic_face_m1n1.py
@@ -11,7 +11,7 @@
 import numpy as np
 
 import geovista as gv
-import geovista.theme  # noqa: F401
+import geovista.theme
 
 
 def main() -> None:
diff --git a/src/geovista/examples/from_2d__synthetic_face_m1n1_robin.py b/src/geovista/examples/from_2d__synthetic_face_m1n1_robin.py
index 755313b2..d1798ad6 100755
--- a/src/geovista/examples/from_2d__synthetic_face_m1n1_robin.py
+++ b/src/geovista/examples/from_2d__synthetic_face_m1n1_robin.py
@@ -11,7 +11,7 @@
 import numpy as np
 
 import geovista as gv
-import geovista.theme  # noqa: F401
+import geovista.theme
 
 
 def main() -> None:
diff --git a/src/geovista/examples/from_2d__synthetic_node_m1n1.py b/src/geovista/examples/from_2d__synthetic_node_m1n1.py
index 5fbd6b70..a6722934 100755
--- a/src/geovista/examples/from_2d__synthetic_node_m1n1.py
+++ b/src/geovista/examples/from_2d__synthetic_node_m1n1.py
@@ -11,7 +11,7 @@
 import numpy as np
 
 import geovista as gv
-import geovista.theme  # noqa: F401
+import geovista.theme
 
 
 def main() -> None:
diff --git a/src/geovista/examples/from_2d__synthetic_node_m1n1_moll.py b/src/geovista/examples/from_2d__synthetic_node_m1n1_moll.py
index 0a7680c3..5504f79e 100755
--- a/src/geovista/examples/from_2d__synthetic_node_m1n1_moll.py
+++ b/src/geovista/examples/from_2d__synthetic_node_m1n1_moll.py
@@ -11,7 +11,7 @@
 import numpy as np
 
 import geovista as gv
-import geovista.theme  # noqa: F401
+import geovista.theme
 
 
 def main() -> None:
diff --git a/src/geovista/examples/from_points__orca_cloud.py b/src/geovista/examples/from_points__orca_cloud.py
index 16270846..72cbde3b 100755
--- a/src/geovista/examples/from_points__orca_cloud.py
+++ b/src/geovista/examples/from_points__orca_cloud.py
@@ -1,3 +1,4 @@
+#!/usr/bin/env python3
 """Importable and runnable geovista example.
 
 Notes
@@ -10,7 +11,7 @@
 import geovista as gv
 from geovista.pantry import um_orca2_gradient
 from geovista.samples import ZLEVEL_SCALE_CLOUD
-import geovista.theme  # noqa: F401
+import geovista.theme
 
 
 def main() -> None:
diff --git a/src/geovista/examples/from_points__orca_cloud_eqc.py b/src/geovista/examples/from_points__orca_cloud_eqc.py
index 111ecb61..b540299b 100755
--- a/src/geovista/examples/from_points__orca_cloud_eqc.py
+++ b/src/geovista/examples/from_points__orca_cloud_eqc.py
@@ -1,3 +1,4 @@
+#!/usr/bin/env python3
 """Importable and runnable geovista example.
 
 Notes
@@ -10,7 +11,7 @@
 import geovista as gv
 from geovista.pantry import um_orca2_gradient
 from geovista.samples import ZLEVEL_SCALE_CLOUD
-import geovista.theme  # noqa: F401
+import geovista.theme
 
 
 def main() -> None:
diff --git a/src/geovista/examples/from_unstructured__fesom.py b/src/geovista/examples/from_unstructured__fesom.py
index 95c0a85e..6d644ec4 100755
--- a/src/geovista/examples/from_unstructured__fesom.py
+++ b/src/geovista/examples/from_unstructured__fesom.py
@@ -10,7 +10,7 @@
 
 import geovista as gv
 from geovista.pantry import fesom
-import geovista.theme  # noqa: F401
+import geovista.theme
 
 
 def main() -> None:
diff --git a/src/geovista/examples/from_unstructured__fesom_fouc.py b/src/geovista/examples/from_unstructured__fesom_fouc.py
index c14dcb13..92d92bd9 100755
--- a/src/geovista/examples/from_unstructured__fesom_fouc.py
+++ b/src/geovista/examples/from_unstructured__fesom_fouc.py
@@ -10,7 +10,7 @@
 
 import geovista as gv
 from geovista.pantry import fesom
-import geovista.theme  # noqa: F401
+import geovista.theme
 
 
 def main() -> None:
diff --git a/src/geovista/examples/from_unstructured__fvcom.py b/src/geovista/examples/from_unstructured__fvcom.py
index 8588bfb3..9a51da61 100755
--- a/src/geovista/examples/from_unstructured__fvcom.py
+++ b/src/geovista/examples/from_unstructured__fvcom.py
@@ -10,7 +10,7 @@
 
 import geovista as gv
 from geovista.pantry import fvcom_tamar
-import geovista.theme  # noqa: F401
+import geovista.theme
 
 
 def main() -> None:
diff --git a/src/geovista/examples/from_unstructured__icon.py b/src/geovista/examples/from_unstructured__icon.py
index 76fd662f..92c48e1e 100755
--- a/src/geovista/examples/from_unstructured__icon.py
+++ b/src/geovista/examples/from_unstructured__icon.py
@@ -12,7 +12,7 @@
 
 import geovista as gv
 from geovista.pantry import icon_soil
-import geovista.theme  # noqa: F401
+import geovista.theme
 
 
 def main() -> None:
diff --git a/src/geovista/examples/from_unstructured__icon_eqc.py b/src/geovista/examples/from_unstructured__icon_eqc.py
index 3eac77d1..911c05ba 100755
--- a/src/geovista/examples/from_unstructured__icon_eqc.py
+++ b/src/geovista/examples/from_unstructured__icon_eqc.py
@@ -12,7 +12,7 @@
 
 import geovista as gv
 from geovista.pantry import icon_soil
-import geovista.theme  # noqa: F401
+import geovista.theme
 
 
 def main() -> None:
diff --git a/src/geovista/examples/from_unstructured__icosahedral.py b/src/geovista/examples/from_unstructured__icosahedral.py
index 7ec89b56..1988b6af 100755
--- a/src/geovista/examples/from_unstructured__icosahedral.py
+++ b/src/geovista/examples/from_unstructured__icosahedral.py
@@ -10,7 +10,7 @@
 
 import geovista as gv
 from geovista.pantry import icosahedral
-import geovista.theme  # noqa: F401
+import geovista.theme
 
 
 def main() -> None:
diff --git a/src/geovista/examples/from_unstructured__icosahedral_poly.py b/src/geovista/examples/from_unstructured__icosahedral_poly.py
index 1e3f33ec..e9a1268d 100755
--- a/src/geovista/examples/from_unstructured__icosahedral_poly.py
+++ b/src/geovista/examples/from_unstructured__icosahedral_poly.py
@@ -10,7 +10,7 @@
 
 import geovista as gv
 from geovista.pantry import icosahedral
-import geovista.theme  # noqa: F401
+import geovista.theme
 
 
 def main() -> None:
diff --git a/src/geovista/examples/from_unstructured__lam_pacific.py b/src/geovista/examples/from_unstructured__lam_pacific.py
index 1a13582b..1917798c 100755
--- a/src/geovista/examples/from_unstructured__lam_pacific.py
+++ b/src/geovista/examples/from_unstructured__lam_pacific.py
@@ -10,7 +10,7 @@
 
 import geovista as gv
 from geovista.pantry import lam_pacific
-import geovista.theme  # noqa: F401
+import geovista.theme
 
 
 def main() -> None:
diff --git a/src/geovista/examples/from_unstructured__lam_pacific_moll.py b/src/geovista/examples/from_unstructured__lam_pacific_moll.py
index 3a9cfd7e..b59e2548 100755
--- a/src/geovista/examples/from_unstructured__lam_pacific_moll.py
+++ b/src/geovista/examples/from_unstructured__lam_pacific_moll.py
@@ -10,7 +10,7 @@
 
 import geovista as gv
 from geovista.pantry import lam_pacific
-import geovista.theme  # noqa: F401
+import geovista.theme
 
 
 def main() -> None:
diff --git a/src/geovista/examples/from_unstructured__lfric_orog.py b/src/geovista/examples/from_unstructured__lfric_orog.py
index 2d3341ff..2a1804b9 100755
--- a/src/geovista/examples/from_unstructured__lfric_orog.py
+++ b/src/geovista/examples/from_unstructured__lfric_orog.py
@@ -10,7 +10,7 @@
 
 import geovista as gv
 from geovista.pantry import lfric_orog
-import geovista.theme  # noqa: F401
+import geovista.theme
 
 
 def main() -> None:
diff --git a/src/geovista/examples/from_unstructured__lfric_orog_warp.py b/src/geovista/examples/from_unstructured__lfric_orog_warp.py
index a4a9264a..3fdb29ca 100755
--- a/src/geovista/examples/from_unstructured__lfric_orog_warp.py
+++ b/src/geovista/examples/from_unstructured__lfric_orog_warp.py
@@ -10,7 +10,7 @@
 
 import geovista as gv
 from geovista.pantry import lfric_orog
-import geovista.theme  # noqa: F401
+import geovista.theme
 
 
 def main() -> None:
diff --git a/src/geovista/examples/from_unstructured__lfric_sst.py b/src/geovista/examples/from_unstructured__lfric_sst.py
index 71a2abea..ff7fde46 100755
--- a/src/geovista/examples/from_unstructured__lfric_sst.py
+++ b/src/geovista/examples/from_unstructured__lfric_sst.py
@@ -10,7 +10,7 @@
 
 import geovista as gv
 from geovista.pantry import lfric_sst
-import geovista.theme  # noqa: F401
+import geovista.theme
 
 
 def main() -> None:
diff --git a/src/geovista/examples/from_unstructured__lfric_sst_bonne.py b/src/geovista/examples/from_unstructured__lfric_sst_bonne.py
index a7da21f6..f90c64b6 100755
--- a/src/geovista/examples/from_unstructured__lfric_sst_bonne.py
+++ b/src/geovista/examples/from_unstructured__lfric_sst_bonne.py
@@ -10,7 +10,7 @@
 
 import geovista as gv
 from geovista.pantry import lfric_sst
-import geovista.theme  # noqa: F401
+import geovista.theme
 
 
 def main() -> None:
diff --git a/src/geovista/examples/from_unstructured__smc.py b/src/geovista/examples/from_unstructured__smc.py
index 1676358a..078a4bbf 100755
--- a/src/geovista/examples/from_unstructured__smc.py
+++ b/src/geovista/examples/from_unstructured__smc.py
@@ -10,7 +10,7 @@
 
 import geovista as gv
 from geovista.pantry import ww3_global_smc
-import geovista.theme  # noqa: F401
+import geovista.theme
 
 
 def main() -> None:
diff --git a/src/geovista/examples/from_unstructured__smc_sinu.py b/src/geovista/examples/from_unstructured__smc_sinu.py
index a87fdca8..f0fdac0f 100755
--- a/src/geovista/examples/from_unstructured__smc_sinu.py
+++ b/src/geovista/examples/from_unstructured__smc_sinu.py
@@ -10,7 +10,7 @@
 
 import geovista as gv
 from geovista.pantry import ww3_global_smc
-import geovista.theme  # noqa: F401
+import geovista.theme
 
 
 def main() -> None:
diff --git a/src/geovista/examples/from_unstructured__tri.py b/src/geovista/examples/from_unstructured__tri.py
index 052b7ab1..fa900b45 100755
--- a/src/geovista/examples/from_unstructured__tri.py
+++ b/src/geovista/examples/from_unstructured__tri.py
@@ -10,7 +10,7 @@
 
 import geovista as gv
 from geovista.pantry import ww3_global_tri
-import geovista.theme  # noqa: F401
+import geovista.theme
 
 
 def main() -> None:
diff --git a/src/geovista/examples/from_unstructured__tri_hammer.py b/src/geovista/examples/from_unstructured__tri_hammer.py
index d0ebaa2f..f4d50856 100755
--- a/src/geovista/examples/from_unstructured__tri_hammer.py
+++ b/src/geovista/examples/from_unstructured__tri_hammer.py
@@ -10,7 +10,7 @@
 
 import geovista as gv
 from geovista.pantry import ww3_global_tri
-import geovista.theme  # noqa: F401
+import geovista.theme
 
 
 def main() -> None:
diff --git a/src/geovista/examples/uber_h3.py b/src/geovista/examples/uber_h3.py
index 5d6b4c0f..1911e694 100755
--- a/src/geovista/examples/uber_h3.py
+++ b/src/geovista/examples/uber_h3.py
@@ -25,7 +25,7 @@
 import numpy as np
 from numpy import ma
 from numpy.typing import ArrayLike
-from pyvista import PolyData
+from pyvista import Actor, PolyData
 
 import geovista
 from geovista.geodesic import line
@@ -98,9 +98,8 @@ def to_mesh(h3indexes: H3Indexes) -> PolyData:
 
     # Create the mesh from the H3 geometry and topology.
     connectivity = ma.masked_equal(connectivity, MDI)
-    mesh = geovista.Transform.from_unstructured(lons, lats, connectivity=connectivity)
 
-    return mesh
+    return geovista.Transform.from_unstructured(lons, lats, connectivity=connectivity)
 
 
 def to_children(h3indexes: H3Indexes) -> H3Indexes:
@@ -175,9 +174,7 @@ def generate_icosahedron_surface(resolution: int | None = 0) -> GeoSurface:
         [11, 7, 9],
     ]
 
-    surface = GeoSurface(lons=lons, lats=lats, connectivity=connectivity)
-
-    return surface
+    return GeoSurface(lons=lons, lats=lats, connectivity=connectivity)
 
 
 def generate_geodesic_edges(surface: GeoSurface) -> PolyData:
@@ -208,9 +205,7 @@ def generate_geodesic_edges(surface: GeoSurface) -> PolyData:
         meshes.append(line(lons, lats))
 
     # Combine the geodesic lines into one mesh.
-    combined = meshes[0].append_polydata(*meshes[1:])
-
-    return combined
+    return meshes[0].append_polydata(*meshes[1:])
 
 
 def add_checkboxes(
@@ -218,7 +213,7 @@ def add_checkboxes(
 ) -> None:
     """Render the checkbox for each ``H3Asset``.
 
-    A checkbox is created for each actor will allows the visibility
+    A checkbox is created for each actor that allows the visibility
     of the actor to be toggled on/off within the `plotter` scene.
 
     Parameters
@@ -236,7 +231,7 @@ def add_checkboxes(
     x, y = 10, 10
     offset = size * 0.2
 
-    def callback(actor, flag):
+    def callback(actor: Actor, flag: bool) -> None:
         actor.SetVisibility(flag)
 
     for i, slot in enumerate(sorted(H3Asset.__slots__)):
diff --git a/src/geovista/examples/vectors.py b/src/geovista/examples/vectors.py
index d57db9b5..5703d7aa 100755
--- a/src/geovista/examples/vectors.py
+++ b/src/geovista/examples/vectors.py
@@ -12,7 +12,7 @@
 
 import geovista as gv
 from geovista.samples import regular_grid
-import geovista.theme  # noqa: F401
+import geovista.theme
 
 
 def main() -> None:
diff --git a/src/geovista/geodesic.py b/src/geovista/geodesic.py
index 5f2bf306..32935365 100644
--- a/src/geovista/geodesic.py
+++ b/src/geovista/geodesic.py
@@ -9,10 +9,10 @@
 
 from collections.abc import Iterable
 from enum import Enum
+from typing import TYPE_CHECKING
 import warnings
 
 import numpy as np
-from numpy.typing import ArrayLike
 import pyproj
 import pyvista as pv
 
@@ -28,6 +28,9 @@
 from .common import cast_UnstructuredGrid_to_PolyData as cast
 from .crs import WGS84, to_wkt
 
+if TYPE_CHECKING:
+    from numpy.typing import ArrayLike
+
 __all__ = [
     "BBox",
     "GEODESIC_NPTS",
@@ -97,7 +100,7 @@
 PREFERENCE: str = "center"
 
 
-# TODO: use StrEnum and auto when minimum supported python version is 3.11
+# TODO @bjlittle: Use StrEnum and auto when minimum supported python version is 3.11.
 class Preference(_MixinStrEnum, Enum):
     """Enumeration of geodesic mesh geometry preferences.
 
@@ -207,18 +210,19 @@ def __init__(
         # cache prior surface radius, as an optimisation
         self._surface_radius = None
 
-    def __eq__(self, other) -> bool:
+    def __eq__(self, other: BBox) -> bool:
         result = NotImplemented
         if isinstance(other, BBox):
             result = False
             lhs = (self.ellps, self.c, self.triangulate)
             rhs = (other.ellps, other.c, other.triangulate)
-            if all(x[0] == x[1] for x in zip(lhs, rhs, strict=True)):
-                if np.allclose(self.lons, other.lons):
-                    result = np.allclose(self.lats, other.lats)
+            if all(x[0] == x[1] for x in zip(lhs, rhs, strict=True)) and np.allclose(
+                self.lons, other.lons
+            ):
+                result = np.allclose(self.lats, other.lats)
         return result
 
-    def __ne__(self, other) -> bool:
+    def __ne__(self, other: BBox) -> bool:
         result = self == other
         if result is not NotImplemented:
             result = not result
@@ -229,11 +233,11 @@ def __repr__(self) -> str:
             f"ellps={self.ellps}, c={self.c}, n_points={self.mesh.n_points}, "
             f"n_cells={self.mesh.n_cells}"
         )
-        result = f"{__package__}.{self.__class__.__name__}<{params}>"
-        return result
+
+        return f"{__package__}.{self.__class__.__name__}<{params}>"
 
     @property
-    def mesh(self):
+    def mesh(self) -> pv.PolyData:
         """The bounding-box :class:`pyvista.PolyData` mesh."""
         if self._mesh is None:
             self._generate_bbox_mesh()
@@ -277,7 +281,7 @@ def _bbox_face_edge_idxs(self) -> np.ndarray:
         .. versionadded:: 0.1.0
 
         """
-        edge = np.concatenate(
+        return np.concatenate(
             [
                 self._idx_map[0],
                 self._idx_map[1:, -1],
@@ -285,7 +289,6 @@ def _bbox_face_edge_idxs(self) -> np.ndarray:
                 self._idx_map[-2:0:-1, 0],
             ]
         )
-        return edge
 
     def _generate_bbox_face(self) -> None:
         """Construct 2-D geodetic bounding-box surface defined by corners.
@@ -313,7 +316,9 @@ def bbox_extend(lons: tuple[float], lats: tuple[float]) -> None:
             self._bbox_lats.extend(lats)
             self._bbox_count += len(lons)
 
-        def bbox_update(idx1, idx2, row=None, column=None) -> None:
+        def bbox_update(
+            idx1: int, idx2: int, row: int | None = None, column: int | None = None
+        ) -> None:
             assert row is not None or column is not None
             if row is None:
                 row = slice(None)
@@ -453,9 +458,7 @@ def _generate_bbox_skirt(self) -> np.ndarray:
         faces_c3 = faces_c2 + self._n_points
         faces_c4 = np.roll(faces_c3, 1)
 
-        faces = np.hstack([faces_n, faces_c1, faces_c2, faces_c3, faces_c4])
-
-        return faces
+        return np.hstack([faces_n, faces_c1, faces_c2, faces_c3, faces_c4])
 
     def boundary(
         self, surface: pv.PolyData | None = None, radius: float | None = None
@@ -577,9 +580,7 @@ def enclosed(
                 selected[scalars].view(bool), adjacent_cells=False
             )
 
-        region = cast(region)
-
-        return region
+        return cast(region)
 
 
 def line(
@@ -664,12 +665,11 @@ def line(
     lons, lats = np.asanyarray(lons), np.asanyarray(lats)
 
     # check whether to auto-repeat lons or lats
-    if lons.size == 1 or lats.size == 1:
-        if lons.size + lats.size > 2:
-            if lons.size == 1:
-                lons = np.repeat(lons[0], lats.size)
-            else:
-                lats = np.repeat(lats[0], lons.size)
+    if (lons.size == 1 or lats.size == 1) and (lons.size + lats.size > 2):
+        if lons.size == 1:
+            lons = np.repeat(lons[0], lats.size)
+        else:
+            lats = np.repeat(lats[0], lons.size)
 
     n_lons, n_lats = lons.size, lats.size
 
@@ -690,13 +690,12 @@ def line(
     lons = wrap(lons)
 
     # check for minimal loop corner case
-    if np.isclose(lons[0], lons[-1]) and np.isclose(lats[0], lats[-1]):
-        if n_lons == 2:
-            emsg = (
-                "Require a closed line (loop) geometry containing at least 3 "
-                f"longitude/latitude values, got '{n_lons}'."
-            )
-            raise ValueError(emsg)
+    if np.isclose(lons[0], lons[-1]) and np.isclose(lats[0], lats[-1]) and n_lons == 2:
+        emsg = (
+            "Require a closed line (loop) geometry containing at least 3 "
+            f"longitude/latitude values, got '{n_lons}'."
+        )
+        raise ValueError(emsg)
 
     line_lons, line_lats = [], []
     geod = pyproj.Geod(ellps=ellps)
@@ -866,7 +865,7 @@ def npoints_by_idx(
     start_lonlat = lons[start_idx], lats[start_idx]
     end_lonlat = lons[end_idx], lats[end_idx]
 
-    result = npoints(
+    return npoints(
         *start_lonlat,
         *end_lonlat,
         npts=npts,
@@ -876,8 +875,6 @@ def npoints_by_idx(
         geod=geod,
     )
 
-    return result
-
 
 def panel(
     name: int | str,
diff --git a/src/geovista/geometry.py b/src/geovista/geometry.py
index 8beebac9..148097e5 100644
--- a/src/geovista/geometry.py
+++ b/src/geovista/geometry.py
@@ -7,12 +7,13 @@
 """
 from __future__ import annotations
 
+from collections.abc import Generator
 from functools import lru_cache
 
 import cartopy.io.shapereader as shp
 import numpy as np
 import pyvista as pv
-from shapely.geometry.multilinestring import MultiLineString
+from shapely import LineString, MultiLineString
 
 from .cache import fetch_coastlines
 from .common import (
@@ -33,6 +34,9 @@
     "load_coastlines",
 ]
 
+# type aliases
+Geometries = Generator[LineString | MultiLineString]
+
 
 @lru_cache(maxsize=LRU_CACHE_SIZE)
 def coastlines(
@@ -123,7 +127,7 @@ def load_coastline_geometries(
     fname = shp.natural_earth(resolution=resolution, category=category, name=name)
     reader = shp.Reader(fname)
 
-    def unpack(geometries):
+    def unpack(geometries: Geometries) -> None:
         for geometry in geometries:
             if isinstance(geometry, MultiLineString):
                 multi_lines.extend(list(geometry.geoms))
diff --git a/src/geovista/geoplotter.py b/src/geovista/geoplotter.py
index 6a1b812c..519ccd84 100644
--- a/src/geovista/geoplotter.py
+++ b/src/geovista/geoplotter.py
@@ -10,13 +10,12 @@
 from __future__ import annotations
 
 from functools import lru_cache
-from typing import Any
+from typing import TYPE_CHECKING, Any
 from warnings import warn
 
-import numpy.typing as npt
 from pyproj import CRS
 import pyvista as pv
-import pyvista.core.utilities.helpers as helpers
+from pyvista.core.utilities import helpers
 
 from .bridge import Transform
 from .common import (
@@ -54,6 +53,9 @@
 from .samples import LFRIC_RESOLUTION, REGULAR_RESOLUTION, lfric, regular_grid
 from .transform import transform_mesh
 
+if TYPE_CHECKING:
+    import numpy.typing as npt
+
 __all__ = ["GeoPlotter"]
 
 #: The valid 'style' options for adding points.
@@ -335,15 +337,12 @@ def add_base_layer(
         if mesh is not None:
             if radius is not None:
                 mesh = resize(mesh, radius=radius)
+        elif resolution.startswith("r"):
+            mesh = regular_grid(resolution=resolution, radius=radius)
         else:
-            if resolution.startswith("r"):
-                mesh = regular_grid(resolution=resolution, radius=radius)
-            else:
-                mesh = _lfric_mesh(resolution=resolution, radius=radius)
-
-        actor = self.add_mesh(mesh, **kwargs)
+            mesh = _lfric_mesh(resolution=resolution, radius=radius)
 
-        return actor
+        return self.add_mesh(mesh, **kwargs)
 
     def add_coastlines(
         self,
@@ -411,9 +410,7 @@ def add_coastlines(
         if atol is not None:
             kwargs["atol"] = atol
 
-        actor = self.add_mesh(mesh, **kwargs)
-
-        return actor
+        return self.add_mesh(mesh, **kwargs)
 
     def add_graticule(
         self,
@@ -618,12 +615,11 @@ def add_mesh(self, mesh: Any, **kwargs: Any | None) -> pv.Actor:
                     inplace=not cloud,
                 )
                 to_wkt(mesh, self.crs)
-            else:
-                if not projected(mesh) and zlevel:
-                    if not cloud:
-                        radius = distance(mesh)
+            elif not projected(mesh) and zlevel:
+                if not cloud:
+                    radius = distance(mesh)
 
-                    mesh = resize(mesh, radius=radius, zlevel=zlevel, zscale=zscale)
+                mesh = resize(mesh, radius=radius, zlevel=zlevel, zscale=zscale)
 
         def _check(option: str) -> bool:
             return option in kwargs and kwargs[option] is not None
@@ -943,7 +939,7 @@ def add_parallels(
         if point_labels_args is None:
             point_labels_args = {}
 
-        # TODO: fix behaviour of longitudes at poles
+        # TODO @bjlittle: Fix behaviour of longitudes at poles.
         poles_parallel = False
 
         parallels = create_parallels(
diff --git a/src/geovista/gridlines.py b/src/geovista/gridlines.py
index 6d4ff717..a3c10a4a 100644
--- a/src/geovista/gridlines.py
+++ b/src/geovista/gridlines.py
@@ -9,9 +9,9 @@
 
 from collections.abc import Iterable
 from dataclasses import dataclass
+from typing import TYPE_CHECKING
 
 import numpy as np
-from numpy.typing import ArrayLike
 import pyvista as pv
 
 from .common import (
@@ -25,6 +25,9 @@
 )
 from .crs import WGS84, to_wkt
 
+if TYPE_CHECKING:
+    from numpy.typing import ArrayLike
+
 __all__ = [
     "GRATICULE_CLOSED_INTERVAL",
     "GRATICULE_ZLEVEL",
@@ -163,17 +166,17 @@ def create_meridian_labels(lons: list[float]) -> list[str]:
         lons = [lons]
 
     for lon in lons:
-        # explicit truncation, perhaps offer format control when required
-        lon = int(lon)
+        # TODO @bjlittle: Explicit truncation is performed, perhaps offer format
+        #                 control when required.
+        value = int(lon)
         direction = LABEL_EAST
 
-        if lon == 0 or np.isclose(np.abs(lon), 180):
+        if value == 0 or np.isclose(np.abs(value), 180):
             direction = LABEL_DEGREE
-        elif lon < 0:
+        elif value < 0:
             direction = LABEL_WEST
 
-        value = np.abs(lon)
-        result.append(f"{value}{direction}")
+        result.append(f"{np.abs(value)}{direction}")
 
     return result
 
@@ -313,7 +316,7 @@ def create_meridians(
             mesh.point_data[GV_REMESH_POINT_IDS] = seam
             mesh.set_active_scalars(name=None)
 
-        blocks[f"{index},{str(lon)}"] = mesh
+        blocks[f"{index},{lon!r}"] = mesh
 
     grid_points, grid_labels = [], []
     labels = create_meridian_labels(list(lons))
@@ -331,12 +334,10 @@ def create_meridians(
     if mask is not None:
         mask = np.tile(mask, grid_lats.size)
 
-    graticule = GraticuleGrid(
+    return GraticuleGrid(
         blocks=blocks, lonlat=grid_points, labels=grid_labels, mask=mask
     )
 
-    return graticule
-
 
 def create_parallel_labels(
     lats: list[float], poles_parallel: bool | None = None
@@ -372,19 +373,18 @@ def create_parallel_labels(
 
     for lat in lats:
         # explicit truncation, perhaps offer format control when required
-        lat = int(lat)
+        value = int(lat)
         direction = LABEL_NORTH
 
-        if lat == 0:
+        if value == 0:
             direction = LABEL_DEGREE
-        elif lat < 0:
+        elif value < 0:
             direction = LABEL_SOUTH
 
-        if not poles_parallel and np.isclose(np.abs(lat), 90):
+        if not poles_parallel and np.isclose(np.abs(value), 90):
             continue
 
-        value = np.abs(lat)
-        result.append(f"{value}{direction}")
+        result.append(f"{np.abs(value)}{direction}")
 
     return result
 
@@ -509,7 +509,7 @@ def create_parallels(
 
         mesh = pv.PolyData(xyz, lines=lines, n_lines=n_points)
         to_wkt(mesh, WGS84)
-        blocks[f"{index},{str(lat)}"] = mesh
+        blocks[f"{index},{lat!r}"] = mesh
         grid_lats.append(lat)
 
     grid_points, grid_labels = [], []
@@ -539,6 +539,5 @@ def create_parallels(
             grid_labels.extend(pole_labels)
 
     grid_points = np.vstack(grid_points)
-    graticule = GraticuleGrid(blocks=blocks, lonlat=grid_points, labels=grid_labels)
 
-    return graticule
+    return GraticuleGrid(blocks=blocks, lonlat=grid_points, labels=grid_labels)
diff --git a/src/geovista/pantry.py b/src/geovista/pantry.py
index 6e08b20e..c8a41789 100644
--- a/src/geovista/pantry.py
+++ b/src/geovista/pantry.py
@@ -12,16 +12,19 @@
 from dataclasses import dataclass, field
 from enum import Enum
 from functools import lru_cache
+from typing import TYPE_CHECKING
 
-import netCDF4 as nc
+import netCDF4 as nc  # noqa: N813
 import numpy as np
 from numpy import ma
-from numpy.typing import ArrayLike
 import pooch
 
 from .cache import CACHE
 from .common import LRU_CACHE_SIZE, _MixinStrEnum
 
+if TYPE_CHECKING:
+    from numpy.typing import ArrayLike
+
 __all__ = [
     "CLOUD_AMOUNT_PREFERENCE",
     "CloudPreference",
@@ -51,7 +54,7 @@
 CLOUD_AMOUNT_PREFERENCE: str = "mesh"
 
 
-# TODO: use StrEnum and auto when minimum supported python version is 3.11
+# TODO @bjlittle: Use StrEnum and auto when minimum supported python version is 3.11.
 class CloudPreference(_MixinStrEnum, Enum):
     """Enumeration of mesh types for cloud amount.
 
@@ -131,9 +134,8 @@ def capitalise(title: str) -> str:
     """
     title = title.replace("_", " ")
     title = title.split(" ")
-    title = " ".join([word.capitalize() for word in title])
 
-    return title
+    return " ".join([word.capitalize() for word in title])
 
 
 def _cloud_amount_dataset(fname: str | CloudPreference) -> nc.Dataset:
@@ -157,9 +159,8 @@ def _cloud_amount_dataset(fname: str | CloudPreference) -> nc.Dataset:
     """
     processor = pooch.Decompress(method="auto", name=fname)
     resource = CACHE.fetch(f"pantry/c768/{fname}.bz2", processor=processor)
-    dataset = nc.Dataset(resource)
 
-    return dataset
+    return nc.Dataset(resource)
 
 
 @lru_cache(maxsize=LRU_CACHE_SIZE)
@@ -220,7 +221,7 @@ def cloud_amount(
         units = data.units
         data = data[:][0]
 
-    sample = SampleUnstructuredXY(
+    return SampleUnstructuredXY(
         lons,
         lats,
         connectivity[:],
@@ -230,8 +231,6 @@ def cloud_amount(
         units=units,
     )
 
-    return sample
-
 
 @lru_cache(maxsize=LRU_CACHE_SIZE)
 def fesom(step: int | None = None) -> SampleUnstructuredXY:
@@ -293,12 +292,10 @@ def fesom(step: int | None = None) -> SampleUnstructuredXY:
     connectivity = ma.arange(np.prod(shape), dtype=np.uint32).reshape(shape)
     connectivity.mask = mask
 
-    sample = SampleUnstructuredXY(
+    return SampleUnstructuredXY(
         lons, lats, connectivity, data=data[idx], name=name, units=units, steps=steps
     )
 
-    return sample
-
 
 @lru_cache(maxsize=LRU_CACHE_SIZE)
 def fvcom_tamar() -> SampleUnstructuredXY:
@@ -335,7 +332,7 @@ def fvcom_tamar() -> SampleUnstructuredXY:
     units = face.units
     node = dataset.variables["h"][:]
 
-    sample = SampleUnstructuredXY(
+    return SampleUnstructuredXY(
         lons,
         lats,
         connectivity.T,
@@ -346,8 +343,6 @@ def fvcom_tamar() -> SampleUnstructuredXY:
         units=units,
     )
 
-    return sample
-
 
 @lru_cache(maxsize=LRU_CACHE_SIZE)
 def icon_soil() -> SampleUnstructuredXY:
@@ -386,12 +381,10 @@ def icon_soil() -> SampleUnstructuredXY:
     name = capitalise("soil type")
     units = "1"
 
-    sample = SampleUnstructuredXY(
+    return SampleUnstructuredXY(
         lons, lats, lons.shape, data=data, name=name, units=units
     )
 
-    return sample
-
 
 @lru_cache(maxsize=LRU_CACHE_SIZE)
 def icosahedral() -> SampleUnstructuredXY:
@@ -423,12 +416,10 @@ def icosahedral() -> SampleUnstructuredXY:
     name = capitalise(data.long_name)
     units = data.units
 
-    sample = SampleUnstructuredXY(
+    return SampleUnstructuredXY(
         lons, lats, lons.shape, data=data, name=name, units=units
     )
 
-    return sample
-
 
 @lru_cache(maxsize=LRU_CACHE_SIZE)
 def _gungho_lam(fname: str) -> SampleUnstructuredXY:
@@ -463,9 +454,7 @@ def _gungho_lam(fname: str) -> SampleUnstructuredXY:
     connectivity = dataset.variables["gungho_face_nodes"]
     start_index = connectivity.start_index
 
-    sample = SampleUnstructuredXY(lons, lats, connectivity[:], start_index=start_index)
-
-    return sample
+    return SampleUnstructuredXY(lons, lats, connectivity[:], start_index=start_index)
 
 
 def lam_equator() -> SampleUnstructuredXY:
@@ -578,7 +567,7 @@ def lam_pacific() -> SampleUnstructuredXY:
     name = capitalise(data.standard_name)
     units = data.units
 
-    sample = SampleUnstructuredXY(
+    return SampleUnstructuredXY(
         lons,
         lats,
         connectivity[:],
@@ -588,8 +577,6 @@ def lam_pacific() -> SampleUnstructuredXY:
         units=units,
     )
 
-    return sample
-
 
 def lam_polar() -> SampleUnstructuredXY:
     """Download and cache unstructured surface sample data.
@@ -662,7 +649,7 @@ def lfric_orog() -> SampleUnstructuredXY:
     name = capitalise(data.standard_name)
     units = data.units
 
-    sample = SampleUnstructuredXY(
+    return SampleUnstructuredXY(
         lons,
         lats,
         connectivity[:],
@@ -672,8 +659,6 @@ def lfric_orog() -> SampleUnstructuredXY:
         units=units,
     )
 
-    return sample
-
 
 @lru_cache(maxsize=LRU_CACHE_SIZE)
 def lfric_sst() -> SampleUnstructuredXY:
@@ -709,7 +694,7 @@ def lfric_sst() -> SampleUnstructuredXY:
     name = capitalise(data.standard_name)
     units = data.units
 
-    sample = SampleUnstructuredXY(
+    return SampleUnstructuredXY(
         lons,
         lats,
         connectivity[:],
@@ -719,8 +704,6 @@ def lfric_sst() -> SampleUnstructuredXY:
         units=units,
     )
 
-    return sample
-
 
 @lru_cache(maxsize=LRU_CACHE_SIZE)
 def oisst_avhrr_sst() -> SampleStructuredXY:
@@ -752,9 +735,7 @@ def oisst_avhrr_sst() -> SampleStructuredXY:
     name = capitalise(data.long_name)
     units = data.units
 
-    sample = SampleStructuredXY(lons, lats, data=data[0, 0], name=name, units=units)
-
-    return sample
+    return SampleStructuredXY(lons, lats, data=data[0, 0], name=name, units=units)
 
 
 @lru_cache(maxsize=LRU_CACHE_SIZE)
@@ -787,9 +768,7 @@ def um_orca2() -> SampleStructuredXY:
     name = capitalise(data.standard_name)
     units = data.units
 
-    sample = SampleStructuredXY(lons, lats, data=data[0, 0], name=name, units=units)
-
-    return sample
+    return SampleStructuredXY(lons, lats, data=data[0, 0], name=name, units=units)
 
 
 @lru_cache(maxsize=LRU_CACHE_SIZE)
@@ -821,9 +800,7 @@ def um_orca2_gradient() -> SampleStructuredXYZ:
     depth = depth[:]
     name = "Depth"
 
-    sample = SampleStructuredXYZ(lons, lats, depth, data=depth, name=name, units=units)
-
-    return sample
+    return SampleStructuredXYZ(lons, lats, depth, data=depth, name=name, units=units)
 
 
 @lru_cache(maxsize=LRU_CACHE_SIZE)
@@ -866,9 +843,7 @@ def usgs_earthquakes() -> SampleStructuredXYZ:
     zlevel = dataset.depth.to_numpy()
     data = dataset.mag.to_numpy()
 
-    sample = SampleStructuredXYZ(lons=lons, lats=lats, zlevel=zlevel, data=data)
-
-    return sample
+    return SampleStructuredXYZ(lons=lons, lats=lats, zlevel=zlevel, data=data)
 
 
 @lru_cache(maxsize=LRU_CACHE_SIZE)
@@ -928,12 +903,10 @@ def ww3_global_smc(step: int | None = None) -> SampleUnstructuredXY:
     name = capitalise(data.standard_name)
     units = data.units
 
-    sample = SampleUnstructuredXY(
+    return SampleUnstructuredXY(
         lons, lats, lons.shape, data=data[idx], name=name, units=units, steps=steps
     )
 
-    return sample
-
 
 @lru_cache(maxsize=LRU_CACHE_SIZE)
 def ww3_global_tri() -> SampleUnstructuredXY:
@@ -972,7 +945,7 @@ def ww3_global_tri() -> SampleUnstructuredXY:
     name = capitalise(data.standard_name)
     units = data.units
 
-    sample = SampleUnstructuredXY(
+    return SampleUnstructuredXY(
         lons,
         lats,
         connectivity,
@@ -981,5 +954,3 @@ def ww3_global_tri() -> SampleUnstructuredXY:
         name=name,
         units=units,
     )
-
-    return sample
diff --git a/src/geovista/report.py b/src/geovista/report.py
index ffdddcaa..d98d0310 100644
--- a/src/geovista/report.py
+++ b/src/geovista/report.py
@@ -117,8 +117,8 @@ def __init__(
         if gpu:
             try:
                 extra_meta = pyvista.GPUInfo().get_info()
-            except:
-                # XXX: bare except required in order to handle rendering faults
+            except:  # noqa: E722
+                # bare except required in order to handle rendering faults
                 extra_meta = [
                     ("GPU Details", "Error"),
                 ]
diff --git a/src/geovista/samples.py b/src/geovista/samples.py
index dede7697..1fdec110 100644
--- a/src/geovista/samples.py
+++ b/src/geovista/samples.py
@@ -86,15 +86,13 @@ def _lfric_sample_to_mesh(sample: pantry.SampleUnstructuredXY) -> pv.PolyData:
     .. versionadded:: 0.1.0
 
     """
-    mesh = Transform.from_unstructured(
+    return Transform.from_unstructured(
         sample.lons,
         sample.lats,
         connectivity=sample.connectivity,
         start_index=sample.start_index,
     )
 
-    return mesh
-
 
 def cloud_amount(preference: str | pantry.CloudPreference | None = None) -> pv.PolyData:
     """Create a mesh from :mod:`geovista.pantry` sample data.
@@ -155,7 +153,7 @@ def fesom() -> pv.PolyData:
     """
     sample = pantry.fesom()
 
-    mesh = Transform.from_unstructured(
+    return Transform.from_unstructured(
         sample.lons,
         sample.lats,
         connectivity=sample.connectivity,
@@ -163,8 +161,6 @@ def fesom() -> pv.PolyData:
         name=sample.name,
     )
 
-    return mesh
-
 
 def fvcom_tamar(
     preference: str | Preference | None = None,
@@ -252,15 +248,13 @@ def icon_soil() -> pv.PolyData:
     """
     sample = pantry.icon_soil()
 
-    mesh = Transform.from_unstructured(
+    return Transform.from_unstructured(
         sample.lons,
         sample.lats,
         data=sample.data,
         name=sample.name,
     )
 
-    return mesh
-
 
 def icosahedral() -> pv.PolyData:
     """Create a mesh from :mod:`geovista.pantry` sample data.
@@ -279,15 +273,13 @@ def icosahedral() -> pv.PolyData:
     """
     sample = pantry.icosahedral()
 
-    mesh = Transform.from_unstructured(
+    return Transform.from_unstructured(
         sample.lons,
         sample.lats,
         data=sample.data,
         name=sample.name,
     )
 
-    return mesh
-
 
 def lam_equator() -> pv.PolyData:
     """Create a mesh from :mod:`geovista.pantry` sample data.
@@ -377,7 +369,7 @@ def lam_pacific() -> pv.PolyData:
     """
     sample = pantry.lam_pacific()
 
-    mesh = Transform.from_unstructured(
+    return Transform.from_unstructured(
         sample.lons,
         sample.lats,
         connectivity=sample.connectivity,
@@ -386,8 +378,6 @@ def lam_pacific() -> pv.PolyData:
         start_index=sample.start_index,
     )
 
-    return mesh
-
 
 def lam_polar() -> pv.PolyData:
     """Create a mesh from :mod:`geovista.pantry` sample data.
@@ -461,9 +451,8 @@ def lfric(resolution: str | None = None) -> pv.PolyData:
     fname = f"lfric_{resolution}.vtk"
     processor = pooch.Decompress(method="auto", name=fname)
     resource = CACHE.fetch(f"mesh/{fname}.bz2", processor=processor)
-    mesh = pv.read(resource)
 
-    return mesh
+    return pv.read(resource)
 
 
 def lfric_orog(warp: bool | None = False, factor: float | None = None) -> pv.PolyData:
@@ -528,7 +517,7 @@ def lfric_sst() -> pv.PolyData:
     """
     sample = pantry.lfric_sst()
 
-    mesh = Transform.from_unstructured(
+    return Transform.from_unstructured(
         sample.lons,
         sample.lats,
         connectivity=sample.connectivity,
@@ -537,8 +526,6 @@ def lfric_sst() -> pv.PolyData:
         start_index=sample.start_index,
     )
 
-    return mesh
-
 
 def regular_grid(
     resolution: str | None = None,
@@ -590,8 +577,8 @@ def warn_unknown() -> None:
 
     lats = np.linspace(-90.0, 90.0, n_cells + 1)
     lons = np.linspace(-180.0, 180.0, int(n_cells * 1.5) + 1)
-    mesh = Transform.from_1d(lons, lats, radius=radius)
-    return mesh
+
+    return Transform.from_1d(lons, lats, radius=radius)
 
 
 def oisst_avhrr_sst() -> pv.PolyData:
@@ -611,15 +598,13 @@ def oisst_avhrr_sst() -> pv.PolyData:
     """
     sample = pantry.oisst_avhrr_sst()
 
-    mesh = Transform.from_1d(
+    return Transform.from_1d(
         sample.lons,
         sample.lats,
         data=sample.data,
         name=sample.name,
     )
 
-    return mesh
-
 
 def um_orca2() -> pv.PolyData:
     """Create a mesh from :mod:`geovista.pantry` sample data.
@@ -638,12 +623,10 @@ def um_orca2() -> pv.PolyData:
     """
     sample = pantry.um_orca2()
 
-    mesh = Transform.from_2d(
+    return Transform.from_2d(
         sample.lons, sample.lats, data=sample.data, name=sample.name
     )
 
-    return mesh
-
 
 def um_orca2_cloud(zscale: float | None = None) -> pv.PolyData:
     """Create a point-cloud mesh from :mod:`geovista.pantry` sample data.
@@ -670,7 +653,7 @@ def um_orca2_cloud(zscale: float | None = None) -> pv.PolyData:
 
     zscale = ZLEVEL_SCALE_CLOUD if zscale is None else float(zscale)
 
-    cloud = Transform.from_points(
+    return Transform.from_points(
         sample.lons,
         sample.lats,
         data=sample.zlevel,
@@ -679,8 +662,6 @@ def um_orca2_cloud(zscale: float | None = None) -> pv.PolyData:
         zscale=zscale,
     )
 
-    return cloud
-
 
 def ww3_global_smc(step: int | None = None) -> pv.PolyData:
     """Create a mesh from :mod:`geovista.pantry` sample data.
@@ -705,7 +686,7 @@ def ww3_global_smc(step: int | None = None) -> pv.PolyData:
     """
     sample = pantry.ww3_global_smc(step=step)
 
-    mesh = Transform.from_unstructured(
+    return Transform.from_unstructured(
         sample.lons,
         sample.lats,
         connectivity=sample.connectivity,
@@ -713,8 +694,6 @@ def ww3_global_smc(step: int | None = None) -> pv.PolyData:
         name=sample.name,
     )
 
-    return mesh
-
 
 def ww3_global_tri() -> pv.PolyData:
     """Create a mesh from :mod:`geovista.pantry` sample data.
@@ -734,12 +713,10 @@ def ww3_global_tri() -> pv.PolyData:
     """
     sample = pantry.ww3_global_tri()
 
-    mesh = Transform.from_unstructured(
+    return Transform.from_unstructured(
         sample.lons,
         sample.lats,
         connectivity=sample.connectivity,
         data=sample.data,
         name=sample.name,
     )
-
-    return mesh
diff --git a/src/geovista/search.py b/src/geovista/search.py
index de1e36ac..dd852a72 100644
--- a/src/geovista/search.py
+++ b/src/geovista/search.py
@@ -9,16 +9,19 @@
 
 from collections.abc import Iterable
 from enum import Enum
+from typing import TYPE_CHECKING
 
 import numpy as np
 from numpy.typing import ArrayLike
 from pykdtree.kdtree import KDTree as pyKDTree
-from pyvista import PolyData
 
 from .common import _MixinStrEnum, to_cartesian
 from .crs import WGS84, from_wkt
 from .transform import transform_points
 
+if TYPE_CHECKING:
+    from pyvista import PolyData
+
 __all__ = ["KDTree", "Preference", "find_cell_neighbours", "find_nearest_cell"]
 
 # type aliases
@@ -39,7 +42,7 @@
 KDTREE_PREFERENCE: str = "point"
 
 
-# TODO: use StrEnum and auto when minimum supported python version is 3.11
+# TODO @bjlittle: Use StrEnum and auto when minimum supported python version is 3.11.
 class Preference(_MixinStrEnum, Enum):
     """Enumeration of mesh geometry preferences.
 
@@ -129,14 +132,14 @@ def __init__(
             transformed = transform_points(
                 src_crs=crs, tgt_crs=WGS84, xs=xyz[:, 0], ys=xyz[:, 1]
             )
-            # TODO: clarify zlevel preservation for non-WGS84 point-clouds
+            # TODO @bjlittle: Clarify zlevel preservation for non-WGS84 point-clouds.
             xyz = to_cartesian(transformed[:, 0], transformed[:, 1])
 
         self._n_points = xyz.shape[0]
         self._mesh_type = mesh.__class__.__name__
         self._kdtree = pyKDTree(xyz, leafsize=leaf_size)
 
-    def __repr__(self):
+    def __repr__(self) -> str:
         """Serialize kd-tree representation.
 
         Returns
@@ -272,12 +275,11 @@ def query(
             epsilon = KDTREE_EPSILON
 
         xyz = to_cartesian(lons, lats, radius=radius, zlevel=zlevel, zscale=zscale)
-        result = self._kdtree.query(
+
+        return self._kdtree.query(
             xyz, k=k, eps=epsilon, distance_upper_bound=distance_upper_bound
         )
 
-        return result
-
 
 def find_cell_neighbours(mesh: PolyData, cid: CellIDLike) -> CellIDs:
     """Find all the cells neighbouring the given `cid` cell/s of the `mesh`.
@@ -308,7 +310,7 @@ def find_cell_neighbours(mesh: PolyData, cid: CellIDLike) -> CellIDs:
 
     pids = []
     for idx in cid:
-        # XXX: pyvista 0.38.0: cell_point_ids(idx) -> get_cell(idx).point_ids
+        # NOTE: pyvista 0.38.0: cell_point_ids(idx) -> get_cell(idx).point_ids
         pids.extend(mesh.get_cell(idx).point_ids)
 
     # determine the unique points
@@ -368,7 +370,7 @@ def find_nearest_cell(
     poi = to_cartesian(x, y)[0] if crs in [WGS84, None] else (x, y, z)
     cid = mesh.find_closest_cell(poi)
 
-    # XXX: pyvista 0.38.0: cell_point_ids(cid) -> get_cell(cid).point_ids
+    # NOTE: pyvista 0.38.0: cell_point_ids(cid) -> get_cell(cid).point_ids
     pids = np.asanyarray(mesh.get_cell(cid).point_ids)
     points = mesh.points[pids]
     mask = np.all(np.isclose(points, poi), axis=1)
@@ -382,9 +384,7 @@ def find_nearest_cell(
 
     if single:
         if (count := len(result)) > 1:
-            emsg = (
-                f"Expected to find 1 cell but found {count}, " f"got CellIDs {result}."
-            )
+            emsg = f"Expected to find 1 cell but found {count}, got CellIDs {result}."
             raise ValueError(emsg)
         (result,) = result
 
diff --git a/src/geovista/transform.py b/src/geovista/transform.py
index df32e707..aaaaa013 100644
--- a/src/geovista/transform.py
+++ b/src/geovista/transform.py
@@ -8,11 +8,10 @@
 from __future__ import annotations
 
 from copy import deepcopy
+from typing import TYPE_CHECKING
 
 import numpy as np
-from numpy.typing import ArrayLike
 from pyproj import CRS, Transformer
-import pyvista as pv
 
 from .common import GV_FIELD_ZSCALE, ZLEVEL_SCALE, from_cartesian, point_cloud
 from .crs import (
@@ -24,6 +23,11 @@
     to_wkt,
 )
 
+if TYPE_CHECKING:
+    from numpy.typing import ArrayLike
+    import pyvista as pv
+
+
 __all__ = [
     "transform_mesh",
     "transform_point",
@@ -147,9 +151,10 @@ def transform_mesh(
         if zlevel or cloud:
             xmin, xmax, ymin, ymax, _, _ = mesh.bounds
             xdelta, ydelta = abs(xmax - xmin), abs(ymax - ymin)
-            # TODO: make this scale factor configurable at the API/module level
-            # current strategy is slightly flawed in that there isn't consistent
-            # scaling across all geometries added to the render
+            # TODO @bjlittle: Make this scale factor configurable at the API/module
+            #                 level, as current strategy is slightly flawed in that
+            #                 there isn't consistent scaling across all geometries
+            #                 added to the render scene.
             delta = max(xdelta, ydelta) // 4
 
             if cloud:
@@ -160,7 +165,7 @@ def transform_mesh(
 
         mesh.points[:, 2] = zs
 
-        # TODO: check whether to clean other field_data metadata
+        # TODO @bjlittle: Check whether to clean other field_data metadata.
         to_wkt(mesh, original_tgt_crs)
 
     return mesh
@@ -169,9 +174,9 @@ def transform_mesh(
 def transform_point(
     src_crs: CRSLike,
     tgt_crs: CRSLike,
-    x: int | float,
-    y: int | float,
-    z: int | float | None = None,
+    x: float,
+    y: float,
+    z: float | None = None,
     trap: bool | None = True,
 ) -> ArrayLike:
     """Transform the spatial point from the source to the target CRS.
diff --git a/tests/bridge/test__as_compatible_data.py b/tests/bridge/test__as_compatible_data.py
index e78f8300..3dc41a4f 100644
--- a/tests/bridge/test__as_compatible_data.py
+++ b/tests/bridge/test__as_compatible_data.py
@@ -2,7 +2,7 @@
 from __future__ import annotations
 
 import numpy as np
-import numpy.ma as ma
+from numpy import ma
 import pytest
 
 from geovista.bridge import Transform
diff --git a/tests/common/conftest.py b/tests/common/conftest.py
index 8a4971fc..db13e47d 100644
--- a/tests/common/conftest.py
+++ b/tests/common/conftest.py
@@ -59,7 +59,7 @@ def degrees(request):
     return request.param
 
 
-@pytest.fixture
+@pytest.fixture()
 def radians(degrees):
     """Fixture for testing single value from cartesian to geographic radians."""
     return Convert(degrees.xyz, np.radians(degrees.expected))
@@ -71,7 +71,7 @@ def manydegrees(request):
     return request.param
 
 
-@pytest.fixture
+@pytest.fixture()
 def manyradians(manydegrees):
     """Fixture for testing multiple values from cartesian to geographic radians."""
     return Convert(manydegrees.xyz, np.radians(np.array(manydegrees.expected)))
diff --git a/tests/common/test_Preference.py b/tests/common/test_Preference.py
index ce3b90dc..877fdc39 100644
--- a/tests/common/test_Preference.py
+++ b/tests/common/test_Preference.py
@@ -24,7 +24,7 @@ def test_values():
 
 
 @pytest.mark.parametrize(
-    "member, expected",
+    ("member", "expected"),
     [
         ("cell", True),
         ("Cell", True),
diff --git a/tests/common/test_distance.py b/tests/common/test_distance.py
index ead1d928..11e54512 100644
--- a/tests/common/test_distance.py
+++ b/tests/common/test_distance.py
@@ -24,7 +24,11 @@ def test_mean_distance(lfric, scale):
 
 
 @pytest.mark.parametrize(
-    "origin", [np.random.randint(0, high=10, size=3).astype(float) for _ in range(10)]
+    "origin",
+    [
+        np.random.default_rng().integers(0, high=10, size=3).astype(float)
+        for _ in range(10)
+    ],
 )
 def test_mean_distance__origin(lfric, origin):
     """Test mean distance with mesh translated to random origin."""
@@ -44,7 +48,11 @@ def test_point_distance(lfric, scale):
 
 
 @pytest.mark.parametrize(
-    "origin", [np.random.randint(0, high=10, size=3).astype(float) for _ in range(10)]
+    "origin",
+    [
+        np.random.default_rng().integers(0, high=10, size=3).astype(float)
+        for _ in range(10)
+    ],
 )
 def test_point_distance__origin(lfric, origin):
     """Test point distance with mesh translated to random origin."""
diff --git a/tests/common/test_from_cartesian.py b/tests/common/test_from_cartesian.py
index 5a52ebfb..16eadb5c 100644
--- a/tests/common/test_from_cartesian.py
+++ b/tests/common/test_from_cartesian.py
@@ -92,20 +92,20 @@ def test_polar_quad_mesh_unfold(sign, n_lons, closed_interval):
 
 @pytest.mark.parametrize("closed_interval", [False, True])
 @pytest.mark.parametrize(
-    "lonlat, pids",
+    ("lonlat", "pids"),
     [
-        [
+        (
             np.array([[170, 10], [180, 10], [-180, 0], [-170, 0]]),
             np.array([[0, 1], [2, 3]]),
-        ],
-        [
+        ),
+        (
             np.array([[170, 0], [180, 0], [-170, 0]]),
             np.array([[0, 1], [1, 2]]),
-        ],
-        [
+        ),
+        (
             np.array([[170, 0], [180, 0], [-180, 0], [-170, 0]]),
             np.array([[0, 1], [2, 3]]),
-        ],
+        ),
     ],
 )
 def test_lines_closed_interval(closed_interval, lonlat, pids):
diff --git a/tests/common/test_nan_mask.py b/tests/common/test_nan_mask.py
index 9b499ca9..faccb9db 100644
--- a/tests/common/test_nan_mask.py
+++ b/tests/common/test_nan_mask.py
@@ -2,7 +2,7 @@
 from __future__ import annotations
 
 import numpy as np
-import numpy.ma as ma
+from numpy import ma
 import pytest
 
 from geovista.common import nan_mask
diff --git a/tests/common/test_sanitize_data.py b/tests/common/test_sanitize_data.py
index 93c41d50..54f9b335 100644
--- a/tests/common/test_sanitize_data.py
+++ b/tests/common/test_sanitize_data.py
@@ -1,9 +1,13 @@
 """Unit-tests for :func:`geovista.common.sanitize_data`."""
 from __future__ import annotations
 
+from typing import TYPE_CHECKING
+
 import numpy as np
 import pytest
-import pyvista as pv
+
+if TYPE_CHECKING:
+    import pyvista as pv
 
 from geovista.common import VTK_CELL_IDS, VTK_POINT_IDS, sanitize_data
 
diff --git a/tests/common/test_to_cartesian.py b/tests/common/test_to_cartesian.py
index adeb718a..55237813 100644
--- a/tests/common/test_to_cartesian.py
+++ b/tests/common/test_to_cartesian.py
@@ -15,8 +15,8 @@ def _distance(pts: npt.ArrayLike, stacked: bool = True) -> float:
     if not stacked:
         pts = np.transpose(pts)
     nrow, ncol = pts.shape
-    result = np.sqrt(np.sum(pts.T @ pts * np.identity(ncol)) / nrow)
-    return result
+
+    return np.sqrt(np.sum(pts.T @ pts * np.identity(ncol)) / nrow)
 
 
 def test_shape_fail():
@@ -61,7 +61,7 @@ def test_zlevel__scalar(lam_uk_sample, zlevel):
 
 
 @pytest.mark.parametrize(
-    "xy_reshape, z_reshape", [((-1,), (-1, 1)), ((1, 5, 5), (-1, 1, 1))]
+    ("xy_reshape", "z_reshape"), [((-1,), (-1, 1)), ((1, 5, 5), (-1, 1, 1))]
 )
 @pytest.mark.parametrize("n_levels", range(3, 11))
 def test_zlevel__broadcast(lam_uk_sample, xy_reshape, z_reshape, n_levels):
diff --git a/tests/common/test_to_lonlat.py b/tests/common/test_to_lonlat.py
index c2b7964c..31a693cc 100644
--- a/tests/common/test_to_lonlat.py
+++ b/tests/common/test_to_lonlat.py
@@ -8,7 +8,7 @@
 
 
 @pytest.mark.parametrize(
-    "point, emsg",
+    ("point", "emsg"),
     [
         (0, r"Require a 1-D array .* got a 0-D array"),
         ([0], r"Require a 1-D array .* got a 1-D array with shape \(1,\)"),
diff --git a/tests/common/test_to_lonlats.py b/tests/common/test_to_lonlats.py
index cd1f9072..e2e8ec5a 100644
--- a/tests/common/test_to_lonlats.py
+++ b/tests/common/test_to_lonlats.py
@@ -8,7 +8,7 @@
 
 
 @pytest.mark.parametrize(
-    "points, emsg",
+    ("points", "emsg"),
     [
         ([[[0]]], r"Require a 2-D array .* got a 3-D array"),
         ([[0, 1]], r"Require a 2-D array .* got a 2-D array with shape \(1, 2\)"),
diff --git a/tests/common/test_wrap.py b/tests/common/test_wrap.py
index 81ff033e..e8cf9b86 100644
--- a/tests/common/test_wrap.py
+++ b/tests/common/test_wrap.py
@@ -101,12 +101,11 @@ def test_base0__dtype(base0, dtype):
 
 
 @pytest.mark.parametrize(
-    "delta, expected", [(1.0e-4, True), (1.0e-3, True), (2.0e-3, False)]
+    ("delta", "expected"), [(1.0e-4, True), (1.0e-3, True), (2.0e-3, False)]
 )
 def test_base_period_tolerance(delta, expected):
     """Test the relative and absolute tolerance of the base + period value."""
     result = wrap(180 - delta)
-    print(result, np.isclose(result, -180))
     assert np.isclose(result, -180)[0] == expected
 
 
diff --git a/tests/conftest.py b/tests/conftest.py
index b9a351a7..a83fab67 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -14,17 +14,17 @@
 from geovista.samples import lfric_sst as sample_lfric_sst
 
 
-@pytest.fixture
+@pytest.fixture()
 def coastlines(request):
     """Fixture generates a coastlines line mesh."""
     # support indirect parameters for fixtures and also
     # calling the fixture with no parameter
     resolution = request.param if hasattr(request, "param") else "110m"
-    mesh = geometry_coastlines(resolution=resolution)
-    return mesh
+
+    return geometry_coastlines(resolution=resolution)
 
 
-@pytest.fixture
+@pytest.fixture()
 def lam_uk():
     """Fixture generates a Local Area Model mesh with indexed faces and points."""
     mesh = sample_lam_uk()
@@ -37,8 +37,8 @@ def lam_uk():
 def lam_uk_cloud(lam_uk_sample):
     """Fixture generates a Local Area Model point-could for the UK."""
     lons, lats = lam_uk_sample
-    cloud = Transform.from_points(lons, lats)
-    return cloud
+
+    return Transform.from_points(lons, lats)
 
 
 @pytest.fixture(scope="session")
@@ -48,14 +48,14 @@ def lam_uk_sample():
     return sample.lons[:], sample.lats[:]
 
 
-@pytest.fixture
+@pytest.fixture()
 def lfric(request):
     """Fixture to provide a cube-sphere mesh."""
     # support indirect parameters for fixtures and also
     # calling the fixture with no parameter
     resolution = request.param if hasattr(request, "param") else "c48"
-    mesh = sample_lfric(resolution=resolution)
-    return mesh
+
+    return sample_lfric(resolution=resolution)
 
 
 @pytest.fixture(scope="session")
@@ -75,7 +75,7 @@ def sphere():
     return pv.Sphere()
 
 
-@pytest.fixture
+@pytest.fixture()
 def wgs84_wkt():
     """Fixture for generating WG284 CRS WKT as a string."""
     return WGS84.to_wkt()
diff --git a/tests/core/test_slice_lines.py b/tests/core/test_slice_lines.py
index 18befb53..5a97f69a 100644
--- a/tests/core/test_slice_lines.py
+++ b/tests/core/test_slice_lines.py
@@ -22,8 +22,8 @@ class Kind:
     detach: int = 0
 
 
-# TODO: add further examples of geovista projected meshes,
-#      this requires "transform_mesh" API support
+# TODO @bjlittle: Add further examples of geovista projected meshes, this requires
+#                 "transform_mesh" API support.
 @pytest.mark.parametrize("mesh", [pv.Plane()])
 def test_projected_fail(mesh):
     """Test trap of a mesh that is projected."""
@@ -114,16 +114,16 @@ def antimeridian_count(mesh: pv.PolyData) -> int:
 
 
 @pytest.mark.parametrize(
-    "lonlat, pids, kind",
+    ("lonlat", "pids", "kind"),
     [
-        [np.array([[179, 0], [181, 0]]), np.array([[0, 1]]), Kind(split=1, detach=0)],
-        [
+        (np.array([[179, 0], [181, 0]]), np.array([[0, 1]]), Kind(split=1, detach=0)),
+        (
             np.array([[179, 0], [180, 0], [181, 0]]),
             np.array([[0, 1], [1, 2]]),
             Kind(split=0, detach=1),
-        ],
-        [np.array([[179, 0], [180, 0]]), np.array([[0, 1]]), Kind(split=0, detach=0)],
-        [np.array([[180, 0], [181, 0]]), np.array([[0, 1]]), Kind(split=0, detach=1)],
+        ),
+        (np.array([[179, 0], [180, 0]]), np.array([[0, 1]]), Kind(split=0, detach=0)),
+        (np.array([[180, 0], [181, 0]]), np.array([[0, 1]]), Kind(split=0, detach=1)),
     ],
 )
 def test_slice_lines(lonlat, pids, kind):
@@ -170,6 +170,6 @@ def test_field_data(coastlines):
     metadata = dict(coastlines.field_data.items())
     result = slice_lines(coastlines)
     assert set(result.field_data.keys()) == set(metadata.keys())
-    for key in metadata.keys():
+    for key in metadata:
         assert id(result.field_data[key]) != id(metadata[key])
         np.testing.assert_array_equal(result.field_data[key], metadata[key])
diff --git a/tests/crs/test_has_wkt.py b/tests/crs/test_has_wkt.py
index 00d3bdb0..b480edc0 100644
--- a/tests/crs/test_has_wkt.py
+++ b/tests/crs/test_has_wkt.py
@@ -6,7 +6,7 @@
 from geovista.crs import has_wkt
 
 
-@pytest.mark.parametrize("mesh, expected", [("sphere", False), ("lfric", True)])
+@pytest.mark.parametrize(("mesh", "expected"), [("sphere", False), ("lfric", True)])
 def test(mesh, expected, request):
     """Test mesh wkt serialization availability."""
     mesh = request.getfixturevalue(mesh)
diff --git a/tests/geodesic/conftest.py b/tests/geodesic/conftest.py
index 764caf25..93b0a09c 100644
--- a/tests/geodesic/conftest.py
+++ b/tests/geodesic/conftest.py
@@ -9,7 +9,7 @@
 CIDS = [11520, 11567, 13776, 13823]
 
 
-@pytest.fixture
+@pytest.fixture()
 def antarctic_corners(lfric_sst):
     """Fixture generates lon/lats of cubed-sphere corner cells centers."""
     cells = lfric_sst.extract_cells(CIDS)
diff --git a/tests/geodesic/test_Preference.py b/tests/geodesic/test_Preference.py
index de66607c..3ee0b6ca 100644
--- a/tests/geodesic/test_Preference.py
+++ b/tests/geodesic/test_Preference.py
@@ -24,7 +24,7 @@ def test_values():
 
 
 @pytest.mark.parametrize(
-    "member, expected",
+    ("member", "expected"),
     [
         ("cell", True),
         ("Cell", True),
diff --git a/tests/geodesic/test_line.py b/tests/geodesic/test_line.py
index 9449a987..ee110d16 100644
--- a/tests/geodesic/test_line.py
+++ b/tests/geodesic/test_line.py
@@ -17,7 +17,7 @@
 
 
 @pytest.mark.parametrize(
-    "lons, lats",
+    ("lons", "lats"),
     [(range(10), range(20)), (list(range(10)), list(range(20)))],
 )
 def test_lons_lats__size_unequal_fail(lons, lats):
@@ -28,7 +28,7 @@ def test_lons_lats__size_unequal_fail(lons, lats):
 
 
 @pytest.mark.parametrize(
-    "lons, lats",
+    ("lons", "lats"),
     [(0, 1), ([0], [1])],
 )
 def test_lons_lats__size_minimal_fail(lons, lats):
@@ -47,7 +47,7 @@ def test_lons_lats__loop_minimal_fail():
 
 
 @pytest.mark.parametrize(
-    "nsamples, npts",
+    ("nsamples", "npts"),
     [(2, None), (2, 64), (3, 128), (4, 256), (8, 512)],
 )
 def test_npts(nsamples, npts):
@@ -76,7 +76,7 @@ def test_contains_sample_points(lfric_sst, nsamples):
 
 
 @pytest.mark.parametrize(
-    "lons, lats",
+    ("lons", "lats"),
     [
         (0, [90, 0, -90]),
         ([0], (90, 45, 0, -45, -90)),
@@ -107,7 +107,7 @@ def test_zlevel(lons, zlevel):
 @pytest.mark.parametrize("zscale", np.linspace(-1, 1))
 def test_zscale(lons, zscale):
     """Test line z-control with zscale."""
-    result = line(180, [90, 0, -90], zscale=zscale)
+    result = line(lons, [90, 0, -90], zscale=zscale)
     actual = distance(result)
     expected = RADIUS + RADIUS * zscale
     assert np.isclose(actual, expected)
diff --git a/tests/geoplotter/test_add_points.py b/tests/geoplotter/test_add_points.py
index 758e9576..dfccc2a1 100644
--- a/tests/geoplotter/test_add_points.py
+++ b/tests/geoplotter/test_add_points.py
@@ -34,7 +34,7 @@ def test_duplicate_points_fail(mocker):
         _ = plotter.add_points(points=points, xs=xs, ys=ys)
 
 
-@pytest.mark.parametrize("xs, ys", [(True, None), (None, True)])
+@pytest.mark.parametrize(("xs", "ys"), [(True, None), (None, True)])
 def test_over_specified_points_fail(mocker, xs, ys):
     """Test trap of points and xs or ys provided."""
     plotter = GeoPlotter()
@@ -93,7 +93,7 @@ def test_texture_kwarg_pop(mocker, sphere):
     plotter.add_mesh.assert_called_once_with(sphere, style="points", scalars=None)
 
 
-@pytest.mark.parametrize("xs, ys", [(None, True), (True, None)])
+@pytest.mark.parametrize(("xs", "ys"), [(None, True), (True, None)])
 def test_xs_ys_incomplete_fail(xs, ys):
     """Test trap of missing spatial points."""
     plotter = GeoPlotter()
diff --git a/tests/gridlines/test__step_period.py b/tests/gridlines/test__step_period.py
index dd1be6a4..4b3f1d55 100644
--- a/tests/gridlines/test__step_period.py
+++ b/tests/gridlines/test__step_period.py
@@ -11,24 +11,20 @@
 def expected(value: float, period: float) -> tuple[float, float]:
     """Calculate expected value within period."""
     count = abs(value) // period
-    if value >= 0:
-        result = value - (count * period)
-    else:
-        result = value + (count * period)
 
-    return result
+    return value - (count * period) if value >= 0 else value + (count * period)
 
 
 @pytest.mark.parametrize(
-    "lon, lat",
+    ("lon", "lat"),
     [
-        [0, 0],
-        [LONGITUDE_STEP_PERIOD // 2, LATITUDE_STEP_PERIOD // 2],
-        [LONGITUDE_STEP_PERIOD, LATITUDE_STEP_PERIOD],
-        [LONGITUDE_STEP_PERIOD * 1.5, LATITUDE_STEP_PERIOD * 1.5],
-        [-LONGITUDE_STEP_PERIOD // 2, -LATITUDE_STEP_PERIOD // 2],
-        [-LONGITUDE_STEP_PERIOD, -LATITUDE_STEP_PERIOD],
-        [-LONGITUDE_STEP_PERIOD * 1.5, -LATITUDE_STEP_PERIOD * 1.5],
+        (0, 0),
+        (LONGITUDE_STEP_PERIOD // 2, LATITUDE_STEP_PERIOD // 2),
+        (LONGITUDE_STEP_PERIOD, LATITUDE_STEP_PERIOD),
+        (LONGITUDE_STEP_PERIOD * 1.5, LATITUDE_STEP_PERIOD * 1.5),
+        (-LONGITUDE_STEP_PERIOD // 2, -LATITUDE_STEP_PERIOD // 2),
+        (-LONGITUDE_STEP_PERIOD, -LATITUDE_STEP_PERIOD),
+        (-LONGITUDE_STEP_PERIOD * 1.5, -LATITUDE_STEP_PERIOD * 1.5),
     ],
 )
 def test(lon, lat):
diff --git a/tests/gridlines/test_create_meridian_labels.py b/tests/gridlines/test_create_meridian_labels.py
index c2cc39c1..d43a8db7 100644
--- a/tests/gridlines/test_create_meridian_labels.py
+++ b/tests/gridlines/test_create_meridian_labels.py
@@ -18,18 +18,18 @@ def test_empty():
 
 
 @pytest.mark.parametrize(
-    "value, expected",
+    ("value", "expected"),
     [
-        [-180, f"180{LABEL_DEGREE}"],
-        [[-180], f"180{LABEL_DEGREE}"],
-        [-90, f"90{LABEL_WEST}"],
-        [[-90], f"90{LABEL_WEST}"],
-        [0, f"0{LABEL_DEGREE}"],
-        [[0], f"0{LABEL_DEGREE}"],
-        [90, f"90{LABEL_EAST}"],
-        [[90], f"90{LABEL_EAST}"],
-        [180, f"180{LABEL_DEGREE}"],
-        [[180], f"180{LABEL_DEGREE}"],
+        (-180, f"180{LABEL_DEGREE}"),
+        ([-180], f"180{LABEL_DEGREE}"),
+        (-90, f"90{LABEL_WEST}"),
+        ([-90], f"90{LABEL_WEST}"),
+        (0, f"0{LABEL_DEGREE}"),
+        ([0], f"0{LABEL_DEGREE}"),
+        (90, f"90{LABEL_EAST}"),
+        ([90], f"90{LABEL_EAST}"),
+        (180, f"180{LABEL_DEGREE}"),
+        ([180], f"180{LABEL_DEGREE}"),
     ],
 )
 def test(value, expected):
@@ -39,13 +39,13 @@ def test(value, expected):
 
 
 @pytest.mark.parametrize(
-    "value, expected",
+    ("value", "expected"),
     [
-        [-180.1, f"180{LABEL_DEGREE}"],
-        [-90.12, f"90{LABEL_WEST}"],
-        [0.123, f"0{LABEL_DEGREE}"],
-        [90.1234, f"90{LABEL_EAST}"],
-        [180.12345, f"180{LABEL_DEGREE}"],
+        (-180.1, f"180{LABEL_DEGREE}"),
+        (-90.12, f"90{LABEL_WEST}"),
+        (0.123, f"0{LABEL_DEGREE}"),
+        (90.1234, f"90{LABEL_EAST}"),
+        (180.12345, f"180{LABEL_DEGREE}"),
     ],
 )
 def test_truncation(value, expected):
diff --git a/tests/gridlines/test_create_meridians.py b/tests/gridlines/test_create_meridians.py
index 242cdbca..b7ca17ad 100644
--- a/tests/gridlines/test_create_meridians.py
+++ b/tests/gridlines/test_create_meridians.py
@@ -64,7 +64,7 @@ def test_core(n_samples, zlevel, step):
     blocks_meridians = deindex(result.blocks.keys())
     assert blocks_meridians == meridians
     # check the meridian meshes (blocks)
-    for key in result.blocks.keys():
+    for key in result.blocks.keys():  # noqa: SIM118
         mesh = result.blocks[key]
         assert mesh.n_points == n_samples
         assert mesh.n_cells == (n_lines := n_samples - 1)
@@ -129,7 +129,7 @@ def test_closed_interval():
     idxs = np.where(np.array(blocks_meridians) == boundary)[0]
     assert idxs.size == 2
     remesh_found = 0
-    for key in result.blocks.keys():
+    for key in result.blocks.keys():  # noqa: SIM118
         mesh = result.blocks[key]
         if deindex(key) == boundary:
             if GV_REMESH_POINT_IDS in mesh.point_data:
diff --git a/tests/gridlines/test_create_parallel_labels.py b/tests/gridlines/test_create_parallel_labels.py
index dc6451de..b1e641de 100644
--- a/tests/gridlines/test_create_parallel_labels.py
+++ b/tests/gridlines/test_create_parallel_labels.py
@@ -18,18 +18,18 @@ def test_empty():
 
 
 @pytest.mark.parametrize(
-    "value, expected",
+    ("value", "expected"),
     [
-        [-90, f"90{LABEL_SOUTH}"],
-        [[-90], f"90{LABEL_SOUTH}"],
-        [-45, f"45{LABEL_SOUTH}"],
-        [[-45], f"45{LABEL_SOUTH}"],
-        [0, f"0{LABEL_DEGREE}"],
-        [[0], f"0{LABEL_DEGREE}"],
-        [45, f"45{LABEL_NORTH}"],
-        [[45], f"45{LABEL_NORTH}"],
-        [90, f"90{LABEL_NORTH}"],
-        [[90], f"90{LABEL_NORTH}"],
+        (-90, f"90{LABEL_SOUTH}"),
+        ([-90], f"90{LABEL_SOUTH}"),
+        (-45, f"45{LABEL_SOUTH}"),
+        ([-45], f"45{LABEL_SOUTH}"),
+        (0, f"0{LABEL_DEGREE}"),
+        ([0], f"0{LABEL_DEGREE}"),
+        (45, f"45{LABEL_NORTH}"),
+        ([45], f"45{LABEL_NORTH}"),
+        (90, f"90{LABEL_NORTH}"),
+        ([90], f"90{LABEL_NORTH}"),
     ],
 )
 def test(value, expected):
@@ -39,13 +39,13 @@ def test(value, expected):
 
 
 @pytest.mark.parametrize(
-    "value, expected",
+    ("value", "expected"),
     [
-        [-90, None],
-        [-45, f"45{LABEL_SOUTH}"],
-        [0, f"0{LABEL_DEGREE}"],
-        [45, f"45{LABEL_NORTH}"],
-        [90, None],
+        (-90, None),
+        (-45, f"45{LABEL_SOUTH}"),
+        (0, f"0{LABEL_DEGREE}"),
+        (45, f"45{LABEL_NORTH}"),
+        (90, None),
     ],
 )
 def test_default_poles_parallel(value, expected):
@@ -56,13 +56,13 @@ def test_default_poles_parallel(value, expected):
 
 
 @pytest.mark.parametrize(
-    "value, expected",
+    ("value", "expected"),
     [
-        [-90.1, f"90{LABEL_SOUTH}"],
-        [-45.12, f"45{LABEL_SOUTH}"],
-        [0.123, f"0{LABEL_DEGREE}"],
-        [45.1234, f"45{LABEL_NORTH}"],
-        [90.12345, f"90{LABEL_NORTH}"],
+        (-90.1, f"90{LABEL_SOUTH}"),
+        (-45.12, f"45{LABEL_SOUTH}"),
+        (0.123, f"0{LABEL_DEGREE}"),
+        (45.1234, f"45{LABEL_NORTH}"),
+        (90.12345, f"90{LABEL_NORTH}"),
     ],
 )
 def test_truncation(value, expected):
diff --git a/tests/gridlines/test_create_parallels.py b/tests/gridlines/test_create_parallels.py
index 0131628d..a0dcc8dc 100644
--- a/tests/gridlines/test_create_parallels.py
+++ b/tests/gridlines/test_create_parallels.py
@@ -63,7 +63,7 @@ def test_core(n_samples, zlevel, poles_label):
     blocks_parallels = deindex(result.blocks.keys())
     assert blocks_parallels == parallels
     # check the parallel meshes (blocks)
-    for key in result.blocks.keys():
+    for key in result.blocks.keys():  # noqa: SIM118
         mesh = result.blocks[key]
         assert mesh.n_points == n_samples
         assert mesh.n_cells == n_samples
@@ -135,7 +135,7 @@ def test_poles_parallel():
     blocks_parallels = deindex(result.blocks.keys())
     assert blocks_parallels == parallels
     # check the parallel meshes (blocks)
-    for key in result.blocks.keys():
+    for key in result.blocks.keys():  # noqa: SIM118
         mesh = result.blocks[key]
         assert mesh.n_points == LATITUDE_N_SAMPLES
         assert mesh.n_cells == LATITUDE_N_SAMPLES
diff --git a/tests/plotting/test_examples.py b/tests/plotting/test_examples.py
index 839ab108..f88590e4 100644
--- a/tests/plotting/test_examples.py
+++ b/tests/plotting/test_examples.py
@@ -52,7 +52,7 @@
 }
 
 
-@pytest.mark.image
+@pytest.mark.image()
 @pytest.mark.parametrize("script", SCRIPTS)
 def test(script, verify_image_cache):
     """Image test the example scripts."""
diff --git a/tests/search/conftest.py b/tests/search/conftest.py
index 67741150..1063fa4a 100644
--- a/tests/search/conftest.py
+++ b/tests/search/conftest.py
@@ -1,14 +1,42 @@
 """pytest fixture infra-structure for :mod:`geovista.search` unit-tests."""
 from __future__ import annotations
 
-from collections import namedtuple
+from typing import TYPE_CHECKING, NamedTuple
 
 import pytest
 
-Center = namedtuple("Center", ["cid", "pids"])
-Neighbour = namedtuple("Neighbour", ["cid", "expected"])
-POI = namedtuple("POI", ["name", "lon", "lat", "cid"])
-Vertex = namedtuple("Vertex", ["pid", "cids"])
+if TYPE_CHECKING:
+    from collections.abc import Iterable
+
+
+class Center(NamedTuple):
+    """Define cell and associated vertices."""
+
+    cid: int
+    pids: Iterable[int]
+
+
+class Neighbour(NamedTuple):
+    """Define cell and associated neighbouring cells."""
+
+    cid: int
+    expected: Iterable[int]
+
+
+class POI(NamedTuple):
+    """Define cell and named geolocated point-of-interest."""
+
+    name: str
+    lon: float
+    lat: float
+    cid: int
+
+
+class Vertex(NamedTuple):
+    """Define vertex and parent cell/s."""
+
+    pid: int
+    cids: Iterable[int]
 
 
 @pytest.fixture(
diff --git a/tests/search/test_Preference.py b/tests/search/test_Preference.py
index 124cc6ae..d9230aa9 100644
--- a/tests/search/test_Preference.py
+++ b/tests/search/test_Preference.py
@@ -24,7 +24,7 @@ def test_values():
 
 
 @pytest.mark.parametrize(
-    "member, expected",
+    ("member", "expected"),
     [
         ("center", True),
         ("Center", True),
diff --git a/tests/search/test_find_nearest_cell.py b/tests/search/test_find_nearest_cell.py
index 42679470..99475a9f 100644
--- a/tests/search/test_find_nearest_cell.py
+++ b/tests/search/test_find_nearest_cell.py
@@ -23,8 +23,8 @@ def test_cell_centers(lam_uk):
 @pytest.mark.xfail(reason="requires projection support")
 def test_cell_centers__lam_rotated_pole():
     """Test requires projection support before implementing."""
-    # TODO: complete this test case
-    raise AssertionError()
+    # TODO @bjlittle: Complete this test case.
+    raise AssertionError
 
 
 def test_poi(lam_uk, poi):
diff --git a/tests/transform/test_transform_points.py b/tests/transform/test_transform_points.py
index 740b4a56..94be8c48 100644
--- a/tests/transform/test_transform_points.py
+++ b/tests/transform/test_transform_points.py
@@ -10,7 +10,7 @@
 
 
 @pytest.mark.parametrize(
-    "src_crs, tgt_crs", [(None, WGS84), (WGS84, None), (None, None)]
+    ("src_crs", "tgt_crs"), [(None, WGS84), (WGS84, None), (None, None)]
 )
 def test_crs_fail(src_crs, tgt_crs):
     """Test trap of invalid source and/or target CRSs."""
@@ -21,7 +21,7 @@ def test_crs_fail(src_crs, tgt_crs):
 
 
 @pytest.mark.parametrize(
-    "xbad, ybad",
+    ("xbad", "ybad"),
     [
         (True, False),
         (False, True),
@@ -44,7 +44,7 @@ def test_xy_dimension_fail(xbad, ybad):
 
 
 @pytest.mark.parametrize(
-    "xs, ys",
+    ("xs", "ys"),
     [(np.arange(10), np.arange(20)), (np.arange(10), np.arange(20).reshape(10, 2))],
 )
 def test_xy_size_fail(xs, ys):