From 2629b2ec6703e6f31c3df58753ad3f54c53f769f Mon Sep 17 00:00:00 2001
From: Deepak Cherian <deepak@cherian.net>
Date: Mon, 4 Dec 2023 22:04:47 -0700
Subject: [PATCH 1/4] repo-review 2

---
 cf_xarray/accessor.py            | 86 ++++++++++++++++----------------
 cf_xarray/criteria.py            |  2 +-
 cf_xarray/formatting.py          | 22 +++-----
 cf_xarray/options.py             |  4 +-
 cf_xarray/tests/test_accessor.py |  8 +--
 cf_xarray/tests/test_helpers.py  |  2 +-
 cf_xarray/units.py               |  8 +--
 cf_xarray/utils.py               | 48 +++++++++++++++++-
 pyproject.toml                   | 16 ++++--
 9 files changed, 123 insertions(+), 73 deletions(-)

diff --git a/cf_xarray/accessor.py b/cf_xarray/accessor.py
index 648f8748..78673d77 100644
--- a/cf_xarray/accessor.py
+++ b/cf_xarray/accessor.py
@@ -4,13 +4,13 @@
 import inspect
 import itertools
 import re
-import warnings
 from collections import ChainMap, namedtuple
 from collections.abc import Hashable, Iterable, Mapping, MutableMapping, Sequence
 from datetime import datetime
 from typing import (
     Any,
     Callable,
+    Literal,
     TypeVar,
     Union,
     cast,
@@ -48,6 +48,7 @@
     _get_version,
     _is_datetime_like,
     always_iterable,
+    emit_user_level_warning,
     invert_mappings,
     parse_cell_methods_attr,
     parse_cf_standard_name_table,
@@ -222,7 +223,7 @@ def _get_custom_criteria(
     try:
         from regex import match as regex_match
     except ImportError:
-        from re import match as regex_match  # type: ignore
+        from re import match as regex_match  # type: ignore[no-redef]
 
     if isinstance(obj, DataArray):
         obj = obj._to_temp_dataset()
@@ -358,8 +359,6 @@ def _get_measure(obj: DataArray | Dataset, key: str) -> list[str]:
             if key in measures:
                 results.update([measures[key]])
 
-    if isinstance(results, str):
-        return [results]
     return list(results)
 
 
@@ -453,7 +452,7 @@ def _get_all(obj: DataArray | Dataset, key: Hashable) -> list[Hashable]:
     """
     all_mappers: tuple[Mapper] = (
         _get_custom_criteria,
-        functools.partial(_get_custom_criteria, criteria=cf_role_criteria),  # type: ignore
+        functools.partial(_get_custom_criteria, criteria=cf_role_criteria),  # type: ignore[assignment]
         functools.partial(_get_custom_criteria, criteria=grid_mapping_var_criteria),
         _get_axis_coord,
         _get_measure,
@@ -491,7 +490,7 @@ def _get_coords(obj: DataArray | Dataset, key: Hashable) -> list[Hashable]:
 def _variables(func: F) -> F:
     @functools.wraps(func)
     def wrapper(obj: DataArray | Dataset, key: Hashable) -> list[DataArray]:
-        return [obj[k] for k in func(obj, key)]  # type: ignore[misc]
+        return [obj[k] for k in func(obj, key)]
 
     return cast(F, wrapper)
 
@@ -636,10 +635,10 @@ def _getattr(
         ):
             raise AttributeError(
                 f"{obj.__class__.__name__+'.cf'!r} object has no attribute {attr!r}"
-            )
+            ) from None
         raise AttributeError(
             f"{attr!r} is not a valid attribute on the underlying xarray object."
-        )
+        ) from None
 
     if isinstance(attribute, Mapping):
         if not attribute:
@@ -663,7 +662,7 @@ def _getattr(
             newmap.update(dict.fromkeys(inverted[key], value))
         newmap.update({key: attribute[key] for key in unused_keys})
 
-        skip: dict[str, list[Hashable] | None] = {
+        skip: dict[str, list[Literal["coords", "measures"]] | None] = {
             "data_vars": ["coords"],
             "coords": None,
         }
@@ -672,7 +671,7 @@ def _getattr(
                 newmap[key] = _getitem(accessor, key, skip=skip[attr])
         return newmap
 
-    elif isinstance(attribute, Callable):  # type: ignore
+    elif isinstance(attribute, Callable):  # type: ignore[arg-type]
         func: Callable = attribute
 
     else:
@@ -704,7 +703,7 @@ def wrapper(*args, **kwargs):
 def _getitem(
     accessor: CFAccessor,
     key: Hashable,
-    skip: list[Hashable] | None = None,
+    skip: list[Literal["coords", "measures"]] | None = None,
 ) -> DataArray:
     ...
 
@@ -713,15 +712,15 @@ def _getitem(
 def _getitem(
     accessor: CFAccessor,
     key: Iterable[Hashable],
-    skip: list[Hashable] | None = None,
+    skip: list[Literal["coords", "measures"]] | None = None,
 ) -> Dataset:
     ...
 
 
 def _getitem(
-    accessor,
-    key,
-    skip=None,
+    accessor: CFAccessor,
+    key: Hashable | Iterable[Hashable],
+    skip: list[Literal["coords", "measures"]] | None = None,
 ):
     """
     Index into obj using key. Attaches CF associated variables.
@@ -772,7 +771,7 @@ def check_results(names, key):
         measures = accessor._get_all_cell_measures()
     except ValueError:
         measures = []
-        warnings.warn("Ignoring bad cell_measures attribute.", UserWarning)
+        emit_user_level_warning("Ignoring bad cell_measures attribute.", UserWarning)
 
     if isinstance(obj, Dataset):
         grid_mapping_names = list(accessor.grid_mapping_names)
@@ -835,6 +834,7 @@ def check_results(names, key):
             )
             coords.extend(itertools.chain(*extravars.values()))
 
+        ds: Dataset
         if isinstance(obj, DataArray):
             ds = obj._to_temp_dataset()
         else:
@@ -842,7 +842,7 @@ def check_results(names, key):
 
         if scalar_key:
             if len(allnames) == 1:
-                da: DataArray = ds.reset_coords()[allnames[0]]  # type: ignore
+                da: DataArray = ds.reset_coords()[allnames[0]]
                 if allnames[0] in coords:
                     coords.remove(allnames[0])
                 for k1 in coords:
@@ -857,18 +857,19 @@ def check_results(names, key):
 
         ds = ds.reset_coords()[varnames + coords]
         if isinstance(obj, DataArray):
-            if scalar_key and len(ds.variables) == 1:
-                # single dimension coordinates
-                assert coords
-                assert not varnames
+            if scalar_key:
+                if len(ds.variables) == 1:
+                    # single dimension coordinates
+                    assert coords
+                    assert not varnames
 
-                return ds[coords[0]]
+                    return ds[coords[0]]
 
-            elif scalar_key and len(ds.variables) > 1:
-                raise NotImplementedError(
-                    "Not sure what to return when given scalar key for DataArray and it has multiple values. "
-                    "Please open an issue."
-                )
+                else:
+                    raise NotImplementedError(
+                        "Not sure what to return when given scalar key for DataArray and it has multiple values. "
+                        "Please open an issue."
+                    )
 
         return ds.set_coords(coords)
 
@@ -876,7 +877,7 @@ def check_results(names, key):
         raise KeyError(
             f"{kind}.cf does not understand the key {k!r}. "
             f"Use 'repr({kind}.cf)' (or '{kind}.cf' in a Jupyter environment) to see a list of key names that can be interpreted."
-        )
+        ) from None
 
 
 def _possible_x_y_plot(obj, key, skip=None):
@@ -1115,7 +1116,7 @@ def _assert_valid_other_comparison(self, other):
             )
         return flag_dict
 
-    def __eq__(self, other) -> DataArray:  # type: ignore
+    def __eq__(self, other) -> DataArray:
         """
         Compare flag values against `other`.
 
@@ -1125,7 +1126,7 @@ def __eq__(self, other) -> DataArray:  # type: ignore
         """
         return self._extract_flags([other])[other].rename(self._obj.name)
 
-    def __ne__(self, other) -> DataArray:  # type: ignore
+    def __ne__(self, other) -> DataArray:
         """
         Compare flag values against `other`.
 
@@ -1247,7 +1248,7 @@ def curvefit(
                 coords_iter = coords
             coords = [
                 apply_mapper(
-                    [_single(_get_coords)], self._obj, v, error=False, default=[v]  # type: ignore
+                    [_single(_get_coords)], self._obj, v, error=False, default=[v]  # type: ignore[arg-type]
                 )[0]
                 for v in coords_iter
             ]
@@ -1258,7 +1259,7 @@ def curvefit(
                 reduce_dims_iter = list(reduce_dims)
             reduce_dims = [
                 apply_mapper(
-                    [_single(_get_dims)], self._obj, v, error=False, default=[v]  # type: ignore
+                    [_single(_get_dims)], self._obj, v, error=False, default=[v]  # type: ignore[arg-type]
                 )[0]
                 for v in reduce_dims_iter
             ]
@@ -1353,7 +1354,7 @@ def _rewrite_values(
 
         # allow multiple return values here.
         # these are valid for .sel, .isel, .coarsen
-        all_mappers = ChainMap(  # type: ignore
+        all_mappers = ChainMap(  # type: ignore[misc]
             key_mappers,
             dict.fromkeys(var_kws, (_get_all,)),
         )
@@ -1442,7 +1443,7 @@ def describe(self):
         Print a string repr to screen.
         """
 
-        warnings.warn(
+        emit_user_level_warning(
             "'obj.cf.describe()' will be removed in a future version. "
             "Use instead 'repr(obj.cf)' or 'obj.cf' in a Jupyter environment.",
             DeprecationWarning,
@@ -1610,10 +1611,9 @@ def cell_measures(self) -> dict[str, list[Hashable]]:
                 bad_vars = list(
                     as_dataset.filter_by_attrs(cell_measures=attr).data_vars.keys()
                 )
-                warnings.warn(
+                emit_user_level_warning(
                     f"Ignoring bad cell_measures attribute: {attr} on {bad_vars}.",
                     UserWarning,
-                    stacklevel=2,
                 )
         measures = {
             key: self._drop_missing_variables(_get_all(self._obj, key)) for key in keys
@@ -1730,9 +1730,9 @@ def get_associated_variable_names(
             except ValueError as e:
                 if error:
                     msg = e.args[0] + " Ignore this error by passing 'error=False'"
-                    raise ValueError(msg)
+                    raise ValueError(msg) from None
                 else:
-                    warnings.warn(
+                    emit_user_level_warning(
                         f"Ignoring bad cell_measures attribute: {attrs_or_encoding['cell_measures']}",
                         UserWarning,
                     )
@@ -1764,7 +1764,7 @@ def get_associated_variable_names(
         missing = set(allvars) - set(self._maybe_to_dataset()._variables)
         if missing:
             if OPTIONS["warn_on_missing_variables"]:
-                warnings.warn(
+                emit_user_level_warning(
                     f"Variables {missing!r} not found in object but are referred to in the CF attributes.",
                     UserWarning,
                 )
@@ -1877,7 +1877,7 @@ def get_renamer_and_conflicts(keydict):
 
         # Rename and warn
         if conflicts:
-            warnings.warn(
+            emit_user_level_warning(
                 "Conflicting variables skipped:\n"
                 + "\n".join(
                     [
@@ -2585,10 +2585,12 @@ def decode_vertical_coords(self, *, outnames=None, prefix=None):
                 try:
                     zname = outnames[dim]
                 except KeyError:
-                    raise KeyError("Your `outnames` need to include a key of `dim`.")
+                    raise KeyError(
+                        "Your `outnames` need to include a key of `dim`."
+                    ) from None
 
             else:
-                warnings.warn(
+                emit_user_level_warning(
                     "`prefix` is being deprecated; use `outnames` instead.",
                     DeprecationWarning,
                 )
diff --git a/cf_xarray/criteria.py b/cf_xarray/criteria.py
index f6bfc56e..f287e5de 100644
--- a/cf_xarray/criteria.py
+++ b/cf_xarray/criteria.py
@@ -128,7 +128,7 @@
 coordinate_criteria["time"] = coordinate_criteria["T"]
 
 # "long_name" and "standard_name" criteria are the same. For convenience.
-for coord, attrs in coordinate_criteria.items():
+for coord in coordinate_criteria:
     coordinate_criteria[coord]["long_name"] = coordinate_criteria[coord][
         "standard_name"
     ]
diff --git a/cf_xarray/formatting.py b/cf_xarray/formatting.py
index c700924c..c818f161 100644
--- a/cf_xarray/formatting.py
+++ b/cf_xarray/formatting.py
@@ -10,7 +10,7 @@
 try:
     from rich.table import Table
 except ImportError:
-    Table = None  # type: ignore
+    Table = None  # type: ignore[assignment, misc]
 
 
 def _format_missing_row(row: str, rich: bool) -> str:
@@ -41,7 +41,7 @@ def _format_cf_name(name: str, rich: bool) -> str:
 def make_text_section(
     accessor,
     subtitle: str,
-    attr: str,
+    attr: str | dict,
     dims=None,
     valid_keys=None,
     valid_values=None,
@@ -140,10 +140,10 @@ def _maybe_panel(textgen, title: str, rich: bool):
             width=100,
         )
         if isinstance(textgen, Table):
-            return Panel(textgen, padding=(0, 20), **kwargs)  # type: ignore
+            return Panel(textgen, padding=(0, 20), **kwargs)  # type: ignore[arg-type]
         else:
             text = "".join(textgen)
-            return Panel(f"[color(241)]{text.rstrip()}[/color(241)]", **kwargs)  # type: ignore
+            return Panel(f"[color(241)]{text.rstrip()}[/color(241)]", **kwargs)  # type: ignore[arg-type]
     else:
         text = "".join(textgen)
         return title + ":\n" + text
@@ -220,22 +220,14 @@ def _format_flags(accessor, rich):
         table.add_column("Value", justify="right")
         table.add_column("Bits", justify="center")
 
-        for val, bit, (key, (mask, value)) in zip(
-            value_text, bit_text, flag_dict.items()
-        ):
-            table.add_row(
-                _format_cf_name(key, rich),
-                val,
-                bit,
-            )
+        for val, bit, key in zip(value_text, bit_text, flag_dict):
+            table.add_row(_format_cf_name(key, rich), val, bit)
 
         return table
 
     else:
         rows = []
-        for val, bit, (key, (mask, value)) in zip(
-            value_text, bit_text, flag_dict.items()
-        ):
+        for val, bit, key in zip(value_text, bit_text, flag_dict):
             rows.append(f"{TAB}{_format_cf_name(key, rich)}: {TAB} {val} {bit}")
         return _print_rows("Flag Meanings", rows, rich)
 
diff --git a/cf_xarray/options.py b/cf_xarray/options.py
index 75749a10..0aee9747 100644
--- a/cf_xarray/options.py
+++ b/cf_xarray/options.py
@@ -47,7 +47,7 @@ class set_options:
 
     def __init__(self, **kwargs):
         self.old = {}
-        for k, v in kwargs.items():
+        for k in kwargs:
             if k not in OPTIONS:
                 raise ValueError(
                     f"argument name {k!r} is not in the set of valid options {set(OPTIONS)!r}"
@@ -57,7 +57,7 @@ def __init__(self, **kwargs):
 
     def _apply_update(self, options_dict):
         options_dict = copy.deepcopy(options_dict)
-        for k, v in options_dict.items():
+        for k in options_dict:
             if k == "custom_criteria":
                 options_dict["custom_criteria"] = always_iterable(
                     options_dict["custom_criteria"], allowed=(tuple, list)
diff --git a/cf_xarray/tests/test_accessor.py b/cf_xarray/tests/test_accessor.py
index 85ac2787..ea3dfbc6 100644
--- a/cf_xarray/tests/test_accessor.py
+++ b/cf_xarray/tests/test_accessor.py
@@ -846,7 +846,7 @@ def test_add_bounds_nd_variable() -> None:
 
     # 2D
     expected = (
-        vertices_to_bounds(  # type: ignore
+        vertices_to_bounds(
             xr.DataArray(
                 np.arange(0, 13, 3).reshape(5, 1) + np.arange(-2, 2).reshape(1, 4),
                 dims=("x", "y"),
@@ -1090,7 +1090,7 @@ def test_docstring() -> None:
     assert "present in .indexes" in airds.cf.resample.__doc__
 
     # Make sure docs are up to date
-    get_all_doc: str = cf_xarray.accessor._get_all.__doc__  # type: ignore
+    get_all_doc: str = cf_xarray.accessor._get_all.__doc__  # type: ignore[assignment]
     all_keys = (
         cf_xarray.accessor._AXIS_NAMES
         + cf_xarray.accessor._COORD_NAMES
@@ -1489,7 +1489,7 @@ def test_new_standard_name_mappers() -> None:
     )
     assert_identical(forecast.cf.chunk({"realization": 1}), forecast.chunk({"M": 1}))
     assert_identical(forecast.cf.isel({"realization": 1}), forecast.isel({"M": 1}))
-    assert_identical(forecast.cf.isel(**{"realization": 1}), forecast.isel(**{"M": 1}))  # type: ignore
+    assert_identical(forecast.cf.isel(**{"realization": 1}), forecast.isel(**{"M": 1}))
     assert_identical(
         forecast.cf.groupby("forecast_reference_time.month").mean(),
         forecast.groupby("S.month").mean(),
@@ -1770,7 +1770,7 @@ def test_add_canonical_attributes(override, skip, verbose, capsys):
     # Catch print
     captured = capsys.readouterr()
     if not verbose:
-        captured.out == ""
+        assert captured.out == ""
 
     # Attributes have been added
     for var in sum(ds.cf.standard_names.values(), []):
diff --git a/cf_xarray/tests/test_helpers.py b/cf_xarray/tests/test_helpers.py
index 96d46c2e..1a26b1bc 100644
--- a/cf_xarray/tests/test_helpers.py
+++ b/cf_xarray/tests/test_helpers.py
@@ -8,7 +8,7 @@
 try:
     from dask.array import Array as DaskArray
 except ImportError:
-    DaskArray = None  # type: ignore
+    DaskArray = None  # type: ignore[assignment, misc]
 
 
 def test_bounds_to_vertices() -> None:
diff --git a/cf_xarray/units.py b/cf_xarray/units.py
index ca57d569..acd48fbe 100644
--- a/cf_xarray/units.py
+++ b/cf_xarray/units.py
@@ -1,7 +1,6 @@
 """Module to provide unit support via pint approximating UDUNITS/CF."""
 import functools
 import re
-import warnings
 
 import pint
 from pint import (  # noqa: F401
@@ -10,6 +9,8 @@
     UnitStrippedWarning,
 )
 
+from .utils import emit_user_level_warning
+
 # from `xclim`'s unit support module with permission of the maintainers
 try:
 
@@ -111,9 +112,10 @@ def repl(m):
 try:
     units.setup_matplotlib()
 except ImportError:
-    warnings.warn(
+    emit_user_level_warning(
         "Import(s) unavailable to set up matplotlib support...skipping this portion "
-        "of the setup."
+        "of the setup.",
+        UserWarning,
     )
 # end of vendored code from MetPy
 
diff --git a/cf_xarray/utils.py b/cf_xarray/utils.py
index df5bb531..5644774c 100644
--- a/cf_xarray/utils.py
+++ b/cf_xarray/utils.py
@@ -1,3 +1,6 @@
+import inspect
+import os
+import warnings
 from collections import defaultdict
 from collections.abc import Iterable
 from typing import Any
@@ -94,7 +97,7 @@ def parse_cf_standard_name_table(source=None):
 
     # Build dictionaries
     info = {}
-    table: dict = {}
+    table = {}
     aliases = {}
     for child in root:
         if child.tag == "entry":
@@ -121,3 +124,46 @@ def _get_version():
     except ImportError:
         pass
     return __version__
+
+
+def find_stack_level(test_mode=False) -> int:
+    """Find the first place in the stack that is not inside xarray.
+
+    This is unless the code emanates from a test, in which case we would prefer
+    to see the xarray source.
+
+    This function is taken from pandas.
+
+    Parameters
+    ----------
+    test_mode : bool
+        Flag used for testing purposes to switch off the detection of test
+        directories in the stack trace.
+
+    Returns
+    -------
+    stacklevel : int
+        First level in the stack that is not part of xarray.
+    """
+    import cf_xarray as cfxr
+
+    pkg_dir = os.path.dirname(cfxr.__file__)
+    test_dir = os.path.join(pkg_dir, "tests")
+
+    # https://stackoverflow.com/questions/17407119/python-inspect-stack-is-slow
+    frame = inspect.currentframe()
+    n = 0
+    while frame:
+        fname = inspect.getfile(frame)
+        if fname.startswith(pkg_dir) and (not fname.startswith(test_dir) or test_mode):
+            frame = frame.f_back
+            n += 1
+        else:
+            break
+    return n
+
+
+def emit_user_level_warning(message, category=None):
+    """Emit a warning at the user level by inspecting the stack trace."""
+    stacklevel = find_stack_level()
+    warnings.warn(message, category=category, stacklevel=stacklevel)
diff --git a/pyproject.toml b/pyproject.toml
index f9c9150a..0bfcb13c 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -65,13 +65,14 @@ exclude = [
     "doc",
 ]
 # E402: module level import not at top of file
-# E501: line too long - let black worry about that
-# E731: do not assign a lambda expression, use a def
+# E501: line too long - let ruff worry about that
 ignore = [
     "E402",
     "E501",
-    "E731",
+    "B018",
+    "B015",
 ]
+[tool.ruff.lint]
 select = [
     # Pyflakes
     "F",
@@ -83,8 +84,11 @@ select = [
     # Pyupgrade
     "UP",
 ]
+extend-select = [
+  "B",  # flake8-bugbear
+]
 
-[tool.ruff.isort]
+[tool.ruff.lint.isort]
 known-first-party = ["cf_xarray"]
 known-third-party = [
     "dask",
@@ -99,6 +103,7 @@ known-third-party = [
     "xarray"
 ]
 
+
 [tool.pytest]
 python_files = "test_*.py"
 testpaths = ["cf_xarray/tests"]
@@ -123,6 +128,9 @@ exclude = "doc|flycheck"
 files = "cf_xarray/"
 show_error_codes = true
 warn_unused_ignores = true
+warn_unreachable = true
+enable_error_code = ["ignore-without-code", "redundant-expr", "truthy-bool"]
+
 
 [[tool.mypy.overrides]]
 module=[

From bb2b68f2bc9593b90ac7b2e7060d8f1141eb392b Mon Sep 17 00:00:00 2001
From: Deepak Cherian <deepak@cherian.net>
Date: Mon, 4 Dec 2023 22:32:43 -0700
Subject: [PATCH 2/4] fix

---
 cf_xarray/formatting.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/cf_xarray/formatting.py b/cf_xarray/formatting.py
index c818f161..65b21495 100644
--- a/cf_xarray/formatting.py
+++ b/cf_xarray/formatting.py
@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 import warnings
 from collections.abc import Hashable, Iterable
 from functools import partial

From 0e382f71d0eec610241e57628cea43ac201f4d9d Mon Sep 17 00:00:00 2001
From: Deepak Cherian <deepak@cherian.net>
Date: Mon, 4 Dec 2023 22:39:59 -0700
Subject: [PATCH 3/4] fixes

---
 cf_xarray/accessor.py            | 4 ++--
 cf_xarray/criteria.py            | 2 +-
 cf_xarray/tests/test_accessor.py | 2 +-
 3 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/cf_xarray/accessor.py b/cf_xarray/accessor.py
index 78673d77..7d249871 100644
--- a/cf_xarray/accessor.py
+++ b/cf_xarray/accessor.py
@@ -108,7 +108,7 @@ def apply_mapper(
     """
 
     if not isinstance(key, Hashable):
-        if default is None:
+        if default is None:  # type: ignore[unreachable]
             raise ValueError(
                 "`default` must be provided when `key` is not not a valid DataArray name (of hashable type)."
             )
@@ -858,7 +858,7 @@ def check_results(names, key):
         ds = ds.reset_coords()[varnames + coords]
         if isinstance(obj, DataArray):
             if scalar_key:
-                if len(ds.variables) == 1:
+                if len(ds.variables) == 1:  # type: ignore[unreachable]
                     # single dimension coordinates
                     assert coords
                     assert not varnames
diff --git a/cf_xarray/criteria.py b/cf_xarray/criteria.py
index f287e5de..76299520 100644
--- a/cf_xarray/criteria.py
+++ b/cf_xarray/criteria.py
@@ -7,7 +7,7 @@
 try:
     import regex as re
 except ImportError:
-    import re  # type: ignore
+    import re  # type: ignore[no-redef]
 
 from collections.abc import Mapping, MutableMapping
 from typing import Any
diff --git a/cf_xarray/tests/test_accessor.py b/cf_xarray/tests/test_accessor.py
index ea3dfbc6..05cdeb2f 100644
--- a/cf_xarray/tests/test_accessor.py
+++ b/cf_xarray/tests/test_accessor.py
@@ -1489,7 +1489,7 @@ def test_new_standard_name_mappers() -> None:
     )
     assert_identical(forecast.cf.chunk({"realization": 1}), forecast.chunk({"M": 1}))
     assert_identical(forecast.cf.isel({"realization": 1}), forecast.isel({"M": 1}))
-    assert_identical(forecast.cf.isel(**{"realization": 1}), forecast.isel(**{"M": 1}))
+    assert_identical(forecast.cf.isel(realization=1), forecast.isel(M=1))
     assert_identical(
         forecast.cf.groupby("forecast_reference_time.month").mean(),
         forecast.groupby("S.month").mean(),

From ac1e5b8fb13793fb0e2f581ecc9d8221c4d0f5a8 Mon Sep 17 00:00:00 2001
From: Deepak Cherian <deepak@cherian.net>
Date: Mon, 4 Dec 2023 22:43:30 -0700
Subject: [PATCH 4/4] more fix

---
 cf_xarray/accessor.py            | 6 +++---
 cf_xarray/tests/test_accessor.py | 2 +-
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/cf_xarray/accessor.py b/cf_xarray/accessor.py
index 7d249871..d5af3e76 100644
--- a/cf_xarray/accessor.py
+++ b/cf_xarray/accessor.py
@@ -490,7 +490,7 @@ def _get_coords(obj: DataArray | Dataset, key: Hashable) -> list[Hashable]:
 def _variables(func: F) -> F:
     @functools.wraps(func)
     def wrapper(obj: DataArray | Dataset, key: Hashable) -> list[DataArray]:
-        return [obj[k] for k in func(obj, key)]
+        return [obj[k] for k in func(obj, key)]  # type: ignore[misc]
 
     return cast(F, wrapper)
 
@@ -1116,7 +1116,7 @@ def _assert_valid_other_comparison(self, other):
             )
         return flag_dict
 
-    def __eq__(self, other) -> DataArray:
+    def __eq__(self, other) -> DataArray:  # type: ignore[override]
         """
         Compare flag values against `other`.
 
@@ -1126,7 +1126,7 @@ def __eq__(self, other) -> DataArray:
         """
         return self._extract_flags([other])[other].rename(self._obj.name)
 
-    def __ne__(self, other) -> DataArray:
+    def __ne__(self, other) -> DataArray:  # type: ignore[override]
         """
         Compare flag values against `other`.
 
diff --git a/cf_xarray/tests/test_accessor.py b/cf_xarray/tests/test_accessor.py
index 05cdeb2f..5063cb62 100644
--- a/cf_xarray/tests/test_accessor.py
+++ b/cf_xarray/tests/test_accessor.py
@@ -846,7 +846,7 @@ def test_add_bounds_nd_variable() -> None:
 
     # 2D
     expected = (
-        vertices_to_bounds(
+        vertices_to_bounds(  # type: ignore[misc]
             xr.DataArray(
                 np.arange(0, 13, 3).reshape(5, 1) + np.arange(-2, 2).reshape(1, 4),
                 dims=("x", "y"),