Repo review bugbear (#9505)

* Use ignore instead of extend-ignore for ruff

* Fix B028 no explicit stacklevel in warnings.warn

* Fix B006, B007 and B011 (auto-fixes)

* B006: mutable argument default
* B007: unused loop control variable
* B011: assert false

* Fix the remaining B006 and B007 manually

* Fix B015: pointless comparisons

* Fix B017: pytest.raises(Exception)

* Fix B023: function definition does not bind loop variable

* Fix B005: strip with multicharacter strings

* Fix B020: loop control variable overrides iterable

* Fix B008: no function call in argument defaults

* Fix B018: useless expression

* Fix B904: raise from within except

* Finally enable ruff bugbear lints

* Fix readthedocs

Author: Armavica

asv_bench/benchmarks/__init__.py

@@ -18,15 +18,15 @@ def decorator(func):
 def requires_dask():
     try:
         import dask  # noqa: F401
-    except ImportError:
-        raise NotImplementedError()
+    except ImportError as err:
+        raise NotImplementedError() from err
 
 
 def requires_sparse():
     try:
         import sparse  # noqa: F401
-    except ImportError:
-        raise NotImplementedError()
+    except ImportError as err:
+        raise NotImplementedError() from err
 
 
 def randn(shape, frac_nan=None, chunks=None, seed=0):

asv_bench/benchmarks/accessors.py

@@ -16,10 +16,10 @@ def setup(self, calendar):
         self.da = xr.DataArray(data, dims="time", coords={"time": time})
 
     def time_dayofyear(self, calendar):
-        self.da.time.dt.dayofyear
+        _ = self.da.time.dt.dayofyear
 
     def time_year(self, calendar):
-        self.da.time.dt.year
+        _ = self.da.time.dt.year
 
     def time_floor(self, calendar):
-        self.da.time.dt.floor("D")
+        _ = self.da.time.dt.floor("D")

asv_bench/benchmarks/dataset_io.py

@@ -606,8 +606,8 @@ def setup(self):
 
         try:
             import distributed
-        except ImportError:
-            raise NotImplementedError()
+        except ImportError as err:
+            raise NotImplementedError() from err
 
         self.client = distributed.Client()
         self.write = create_delayed_write()

ci/min_deps_check.py

@@ -68,8 +68,8 @@ def parse_requirements(fname) -> Iterator[tuple[str, int, int, int | None]]:
 
         try:
             version_tup = tuple(int(x) for x in version.split("."))
-        except ValueError:
-            raise ValueError("non-numerical version: " + row)
+        except ValueError as err:
+            raise ValueError("non-numerical version: " + row) from err
 
         if len(version_tup) == 2:
             yield (pkg, *version_tup, None)  # type: ignore[misc]

doc/user-guide/hierarchical-data.rst

@@ -200,7 +200,7 @@ and even the distinguishing feature of the common ancestor of any two species (t
 
 .. ipython:: python
 
-    [node.name for node in primates.ancestors]
+    [node.name for node in reversed(primates.parents)]
     primates.root.name
     primates.find_common_ancestor(dinosaurs).name
 

pyproject.toml

@@ -246,13 +246,14 @@ extend-exclude = [
 extend-safe-fixes = [
   "TID252", # absolute imports
 ]
-extend-ignore = [
+ignore = [
   "E402",
   "E501",
   "E731",
   "UP007",
 ]
 extend-select = [
+  "B", # flake8-bugbear
   "F", # Pyflakes
   "E", # Pycodestyle
   "W",

xarray/backends/api.py

@@ -99,11 +99,11 @@ def _get_default_engine_remote_uri() -> Literal["netcdf4", "pydap"]:
             import pydap  # noqa: F401
 
             engine = "pydap"
-        except ImportError:
+        except ImportError as err:
             raise ValueError(
                 "netCDF4 or pydap is required for accessing "
                 "remote datasets via OPeNDAP"
-            )
+            ) from err
     return engine
 
 
@@ -112,8 +112,8 @@ def _get_default_engine_gz() -> Literal["scipy"]:
         import scipy  # noqa: F401
 
         engine: Final = "scipy"
-    except ImportError:  # pragma: no cover
-        raise ValueError("scipy is required for accessing .gz files")
+    except ImportError as err:  # pragma: no cover
+        raise ValueError("scipy is required for accessing .gz files") from err
     return engine
 
 
@@ -128,11 +128,11 @@ def _get_default_engine_netcdf() -> Literal["netcdf4", "scipy"]:
             import scipy.io.netcdf  # noqa: F401
 
             engine = "scipy"
-        except ImportError:
+        except ImportError as err:
             raise ValueError(
                 "cannot read or write netCDF files without "
                 "netCDF4-python or scipy installed"
-            )
+            ) from err
     return engine
 
 
@@ -1374,8 +1374,8 @@ def to_netcdf(
 
     try:
         store_open = WRITEABLE_STORES[engine]
-    except KeyError:
-        raise ValueError(f"unrecognized engine for to_netcdf: {engine!r}")
+    except KeyError as err:
+        raise ValueError(f"unrecognized engine for to_netcdf: {engine!r}") from err
 
     if format is not None:
         format = format.upper()  # type: ignore[assignment]

xarray/backends/netCDF4_.py

@@ -111,7 +111,7 @@ def _getitem(self, key):
             with self.datastore.lock:
                 original_array = self.get_array(needs_lock=False)
                 array = getitem(original_array, key)
-        except IndexError:
+        except IndexError as err:
             # Catch IndexError in netCDF4 and return a more informative
             # error message.  This is most often called when an unsorted
             # indexer is used before the data is loaded from disk.
@@ -120,7 +120,7 @@ def _getitem(self, key):
                 "is not valid on netCDF4.Variable object. Try loading "
                 "your data into memory first by calling .load()."
             )
-            raise IndexError(msg)
+            raise IndexError(msg) from err
         return array
 
 
@@ -192,7 +192,7 @@ def _nc4_require_group(ds, group, mode, create_group=_netcdf4_create_group):
                     ds = create_group(ds, key)
                 else:
                     # wrap error to provide slightly more helpful message
-                    raise OSError(f"group not found: {key}", e)
+                    raise OSError(f"group not found: {key}", e) from e
         return ds
 
 

xarray/backends/plugins.py

@@ -40,6 +40,7 @@ def remove_duplicates(entrypoints: EntryPoints) -> list[EntryPoint]:
                 f"\n {all_module_names}.\n "
                 f"The entrypoint {selected_module_name} will be used.",
                 RuntimeWarning,
+                stacklevel=2,
             )
     return unique_entrypoints
 
@@ -72,7 +73,9 @@ def backends_dict_from_pkg(
             backend = entrypoint.load()
             backend_entrypoints[name] = backend
         except Exception as ex:
-            warnings.warn(f"Engine {name!r} loading failed:\n{ex}", RuntimeWarning)
+            warnings.warn(
+                f"Engine {name!r} loading failed:\n{ex}", RuntimeWarning, stacklevel=2
+            )
     return backend_entrypoints
 
 
@@ -146,7 +149,9 @@ def guess_engine(
         except PermissionError:
             raise
         except Exception:
-            warnings.warn(f"{engine!r} fails while guessing", RuntimeWarning)
+            warnings.warn(
+                f"{engine!r} fails while guessing", RuntimeWarning, stacklevel=2
+            )
 
     compatible_engines = []
     for engine, (_, backend_cls) in BACKEND_ENTRYPOINTS.items():
@@ -155,7 +160,9 @@ def guess_engine(
             if backend.guess_can_open(store_spec):
                 compatible_engines.append(engine)
         except Exception:
-            warnings.warn(f"{engine!r} fails while guessing", RuntimeWarning)
+            warnings.warn(
+                f"{engine!r} fails while guessing", RuntimeWarning, stacklevel=2
+            )
 
     installed_engines = [k for k in engines if k != "store"]
     if not compatible_engines:

xarray/backends/scipy_.py

@@ -114,7 +114,9 @@ def _open_scipy_netcdf(filename, mode, mmap, version):
             # TODO: gzipped loading only works with NetCDF3 files.
             errmsg = e.args[0]
             if "is not a valid NetCDF 3 file" in errmsg:
-                raise ValueError("gzipped file loading only supports NetCDF 3 files.")
+                raise ValueError(
+                    "gzipped file loading only supports NetCDF 3 files."
+                ) from e
             else:
                 raise
 
@@ -134,7 +136,7 @@ def _open_scipy_netcdf(filename, mode, mmap, version):
             $ pip install netcdf4
             """
             errmsg += msg
-            raise TypeError(errmsg)
+            raise TypeError(errmsg) from e
         else:
             raise