pyupgrade one-off run (#3190)

* pyupgrade (manually vetted and tweaked)

* pyupgrade

* Tweaks to Dataset.drop_dims()

* mypy

* More concise code

setup.cfg

@@ -83,6 +83,8 @@ ignore_missing_imports = True
 ignore_missing_imports = True
 [mypy-seaborn.*]
 ignore_missing_imports = True
+[mypy-sparse.*]
+ignore_missing_imports = True
 [mypy-toolz.*]
 ignore_missing_imports = True
 [mypy-zarr.*]

versioneer.py

@@ -398,7 +398,7 @@ def run_command(commands, args, cwd=None, verbose=False, hide_stderr=False,
                                  stderr=(subprocess.PIPE if hide_stderr
                                          else None))
             break
-        except EnvironmentError:
+        except OSError:
             e = sys.exc_info()[1]
             if e.errno == errno.ENOENT:
                 continue
@@ -421,7 +421,7 @@ def run_command(commands, args, cwd=None, verbose=False, hide_stderr=False,
     return stdout, p.returncode
 
 
-LONG_VERSION_PY['git'] = '''
+LONG_VERSION_PY['git'] = r'''
 # This file helps to compute a version number in source trees obtained from
 # git-archive tarball (such as those provided by githubs download-from-tag
 # feature). Distribution tarballs (built by setup.py sdist) and build
@@ -968,7 +968,7 @@ def git_get_keywords(versionfile_abs):
                 if mo:
                     keywords["date"] = mo.group(1)
         f.close()
-    except EnvironmentError:
+    except OSError:
         pass
     return keywords
 
@@ -992,11 +992,11 @@ def git_versions_from_keywords(keywords, tag_prefix, verbose):
         if verbose:
             print("keywords are unexpanded, not using")
         raise NotThisMethod("unexpanded keywords, not a git-archive tarball")
-    refs = set([r.strip() for r in refnames.strip("()").split(",")])
+    refs = {r.strip() for r in refnames.strip("()").split(",")}
     # starting in git-1.8.3, tags are listed as "tag: foo-1.0" instead of
     # just "foo-1.0". If we see a "tag: " prefix, prefer those.
     TAG = "tag: "
-    tags = set([r[len(TAG):] for r in refs if r.startswith(TAG)])
+    tags = {r[len(TAG):] for r in refs if r.startswith(TAG)}
     if not tags:
         # Either we're using git < 1.8.3, or there really are no tags. We use
         # a heuristic: assume all version tags have a digit. The old git %d
@@ -1005,7 +1005,7 @@ def git_versions_from_keywords(keywords, tag_prefix, verbose):
         # between branches and tags. By ignoring refnames without digits, we
         # filter out many common branch names like "release" and
         # "stabilization", as well as "HEAD" and "master".
-        tags = set([r for r in refs if re.search(r'\d', r)])
+        tags = {r for r in refs if re.search(r'\d', r)}
         if verbose:
             print("discarding '%s', no digits" % ",".join(refs - tags))
     if verbose:
@@ -1148,7 +1148,7 @@ def do_vcs_install(manifest_in, versionfile_source, ipy):
                 if "export-subst" in line.strip().split()[1:]:
                     present = True
         f.close()
-    except EnvironmentError:
+    except OSError:
         pass
     if not present:
         f = open(".gitattributes", "a+")
@@ -1206,7 +1206,7 @@ def versions_from_file(filename):
     try:
         with open(filename) as f:
             contents = f.read()
-    except EnvironmentError:
+    except OSError:
         raise NotThisMethod("unable to read _version.py")
     mo = re.search(r"version_json = '''\n(.*)'''  # END VERSION_JSON",
                    contents, re.M | re.S)
@@ -1702,8 +1702,7 @@ def do_setup():
     root = get_root()
     try:
         cfg = get_config_from_root(root)
-    except (EnvironmentError, configparser.NoSectionError,
-            configparser.NoOptionError) as e:
+    except (OSError, configparser.NoSectionError, configparser.NoOptionError) as e:
         if isinstance(e, (EnvironmentError, configparser.NoSectionError)):
             print("Adding sample versioneer config to setup.cfg",
                   file=sys.stderr)
@@ -1728,7 +1727,7 @@ def do_setup():
         try:
             with open(ipy, "r") as f:
                 old = f.read()
-        except EnvironmentError:
+        except OSError:
             old = ""
         if INIT_PY_SNIPPET not in old:
             print(" appending to %s" % ipy)
@@ -1752,7 +1751,7 @@ def do_setup():
                 if line.startswith("include "):
                     for include in line.split()[1:]:
                         simple_includes.add(include)
-    except EnvironmentError:
+    except OSError:
         pass
     # That doesn't cover everything MANIFEST.in can do
     # (http://docs.python.org/2/distutils/sourcedist.html#commands), so

xarray/_version.py

@@ -81,7 +81,7 @@ def run_command(commands, args, cwd=None, verbose=False, hide_stderr=False,
                                  stderr=(subprocess.PIPE if hide_stderr
                                          else None))
             break
-        except EnvironmentError:
+        except OSError:
             e = sys.exc_info()[1]
             if e.errno == errno.ENOENT:
                 continue
@@ -153,7 +153,7 @@ def git_get_keywords(versionfile_abs):
                 if mo:
                     keywords["date"] = mo.group(1)
         f.close()
-    except EnvironmentError:
+    except OSError:
         pass
     return keywords
 
@@ -177,11 +177,11 @@ def git_versions_from_keywords(keywords, tag_prefix, verbose):
         if verbose:
             print("keywords are unexpanded, not using")
         raise NotThisMethod("unexpanded keywords, not a git-archive tarball")
-    refs = set([r.strip() for r in refnames.strip("()").split(",")])
+    refs = {r.strip() for r in refnames.strip("()").split(",")}
     # starting in git-1.8.3, tags are listed as "tag: foo-1.0" instead of
     # just "foo-1.0". If we see a "tag: " prefix, prefer those.
     TAG = "tag: "
-    tags = set([r[len(TAG):] for r in refs if r.startswith(TAG)])
+    tags = {r[len(TAG):] for r in refs if r.startswith(TAG)}
     if not tags:
         # Either we're using git < 1.8.3, or there really are no tags. We use
         # a heuristic: assume all version tags have a digit. The old git %d
@@ -190,7 +190,7 @@ def git_versions_from_keywords(keywords, tag_prefix, verbose):
         # between branches and tags. By ignoring refnames without digits, we
         # filter out many common branch names like "release" and
         # "stabilization", as well as "HEAD" and "master".
-        tags = set([r for r in refs if re.search(r'\d', r)])
+        tags = {r for r in refs if re.search(r'\d', r)}
         if verbose:
             print("discarding '%s', no digits" % ",".join(refs - tags))
     if verbose:

xarray/backends/api.py

@@ -752,7 +752,7 @@ def open_mfdataset(paths, chunks=None, concat_dim='_not_supplied',
         paths = [str(p) if isinstance(p, Path) else p for p in paths]
 
     if not paths:
-        raise IOError('no files to open')
+        raise OSError('no files to open')
 
     # If combine='by_coords' then this is unnecessary, but quick.
     # If combine='nested' then this creates a flat list which is easier to
@@ -1051,7 +1051,7 @@ def save_mfdataset(datasets, paths, mode='w', format=None, groups=None,
     if groups is None:
         groups = [None] * len(datasets)
 
-    if len(set([len(datasets), len(paths), len(groups)])) > 1:
+    if len({len(datasets), len(paths), len(groups)}) > 1:
         raise ValueError('must supply lists of the same length for the '
                          'datasets, paths and groups arguments to '
                          'save_mfdataset')

xarray/backends/netCDF4_.py

@@ -138,7 +138,7 @@ def _netcdf4_create_group(dataset, name):
 
 
 def _nc4_require_group(ds, group, mode, create_group=_netcdf4_create_group):
-    if group in set([None, '', '/']):
+    if group in {None, '', '/'}:
         # use the root group
         return ds
     else:
@@ -155,7 +155,7 @@ 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 IOError('group not found: %s' % key, e)
+                    raise OSError('group not found: %s' % key, e)
         return ds
 
 
@@ -195,9 +195,11 @@ def _extract_nc4_variable_encoding(variable, raise_on_invalid=False,
 
     encoding = variable.encoding.copy()
 
-    safe_to_drop = set(['source', 'original_shape'])
-    valid_encodings = set(['zlib', 'complevel', 'fletcher32', 'contiguous',
-                           'chunksizes', 'shuffle', '_FillValue', 'dtype'])
+    safe_to_drop = {'source', 'original_shape'}
+    valid_encodings = {
+        'zlib', 'complevel', 'fletcher32', 'contiguous',
+        'chunksizes', 'shuffle', '_FillValue', 'dtype'
+    }
     if lsd_okay:
         valid_encodings.add('least_significant_digit')
     if h5py_okay:

xarray/backends/netcdf3.py

@@ -11,9 +11,10 @@
 
 # The following are reserved names in CDL and may not be used as names of
 # variables, dimension, attributes
-_reserved_names = set(['byte', 'char', 'short', 'ushort', 'int', 'uint',
-                       'int64', 'uint64', 'float' 'real', 'double', 'bool',
-                       'string'])
+_reserved_names = {
+    'byte', 'char', 'short', 'ushort', 'int', 'uint', 'int64', 'uint64',
+    'float' 'real', 'double', 'bool', 'string'
+}
 
 # These data-types aren't supported by netCDF3, so they are automatically
 # coerced instead as indicated by the "coerce_nc3_dtype" function
@@ -108,4 +109,4 @@ def is_valid_nc3_name(s):
             ('/' not in s) and
             (s[-1] != ' ') and
             (_isalnumMUTF8(s[0]) or (s[0] == '_')) and
-            all((_isalnumMUTF8(c) or c in _specialchars for c in s)))
+            all(_isalnumMUTF8(c) or c in _specialchars for c in s))

xarray/backends/pseudonetcdf_.py

@@ -75,18 +75,18 @@ def get_variables(self):
                                  for k, v in self.ds.variables.items())
 
     def get_attrs(self):
-        return Frozen(dict([(k, getattr(self.ds, k))
-                            for k in self.ds.ncattrs()]))
+        return Frozen({k: getattr(self.ds, k) for k in self.ds.ncattrs()})
 
     def get_dimensions(self):
         return Frozen(self.ds.dimensions)
 
     def get_encoding(self):
-        encoding = {}
-        encoding['unlimited_dims'] = set(
-            [k for k in self.ds.dimensions
-             if self.ds.dimensions[k].isunlimited()])
-        return encoding
+        return {
+            'unlimited_dims': {
+                k for k in self.ds.dimensions
+                if self.ds.dimensions[k].isunlimited()
+            }
+        }
 
     def close(self):
         self._manager.close()

xarray/backends/pynio_.py

@@ -75,10 +75,12 @@ def get_dimensions(self):
         return Frozen(self.ds.dimensions)
 
     def get_encoding(self):
-        encoding = {}
-        encoding['unlimited_dims'] = set(
-            [k for k in self.ds.dimensions if self.ds.unlimited(k)])
-        return encoding
+        return {
+            'unlimited_dims': {
+                k for k in self.ds.dimensions
+                if self.ds.unlimited(k)
+            }
+        }
 
     def close(self):
         self._manager.close()

xarray/backends/zarr.py

@@ -166,8 +166,7 @@ def _get_zarr_dims_and_attrs(zarr_obj, dimension_key):
 def _extract_zarr_variable_encoding(variable, raise_on_invalid=False):
     encoding = variable.encoding.copy()
 
-    valid_encodings = set(['chunks', 'compressor', 'filters',
-                           'cache_metadata'])
+    valid_encodings = {'chunks', 'compressor', 'filters', 'cache_metadata'}
 
     if raise_on_invalid:
         invalid = [k for k in encoding if k not in valid_encodings]
@@ -340,8 +339,10 @@ def store(self, variables, attributes, check_encoding_set=frozenset(),
             only needed in append mode
         """
 
-        existing_variables = set([vn for vn in variables
-                                 if _encode_variable_name(vn) in self.ds])
+        existing_variables = {
+            vn for vn in variables
+            if _encode_variable_name(vn) in self.ds
+        }
         new_variables = set(variables) - existing_variables
         variables_without_encoding = OrderedDict([(vn, variables[vn])
                                                  for vn in new_variables])

xarray/coding/cftime_offsets.py

@@ -637,7 +637,7 @@ def __apply__(self, other):
 
 
 _FREQUENCY_CONDITION = '|'.join(_FREQUENCIES.keys())
-_PATTERN = r'^((?P<multiple>\d+)|())(?P<freq>({0}))$'.format(
+_PATTERN = r'^((?P<multiple>\d+)|())(?P<freq>({}))$'.format(
     _FREQUENCY_CONDITION)
 
 

xarray/coding/times.py

@@ -23,7 +23,7 @@
 
 
 # standard calendars recognized by cftime
-_STANDARD_CALENDARS = set(['standard', 'gregorian', 'proleptic_gregorian'])
+_STANDARD_CALENDARS = {'standard', 'gregorian', 'proleptic_gregorian'}
 
 _NS_PER_TIME_DELTA = {'us': int(1e3),
                       'ms': int(1e6),

xarray/conventions.py

@@ -186,7 +186,7 @@ def ensure_dtype_not_object(var, name=None):
             if strings.is_bytes_dtype(inferred_dtype):
                 fill_value = b''
             elif strings.is_unicode_dtype(inferred_dtype):
-                fill_value = u''
+                fill_value = ''
             else:
                 # insist on using float for numeric values
                 if not np.issubdtype(inferred_dtype, np.floating):

xarray/convert.py

@@ -30,7 +30,7 @@ def encode(var):
 def _filter_attrs(attrs, ignored_attrs):
     """ Return attrs that are not in ignored_attrs
     """
-    return dict((k, v) for k, v in attrs.items() if k not in ignored_attrs)
+    return {k: v for k, v in attrs.items() if k not in ignored_attrs}
 
 
 def from_cdms2(variable):
@@ -119,7 +119,7 @@ def set_cdms2_attrs(var, attrs):
 def _pick_attrs(attrs, keys):
     """ Return attrs with keys in keys list
     """
-    return dict((k, v) for k, v in attrs.items() if k in keys)
+    return {k: v for k, v in attrs.items() if k in keys}
 
 
 def _get_iris_args(attrs):
@@ -188,7 +188,7 @@ def _iris_obj_to_attrs(obj):
     if obj.units.origin != '1' and not obj.units.is_unknown():
         attrs['units'] = obj.units.origin
     attrs.update(obj.attributes)
-    return dict((k, v) for k, v in attrs.items() if v is not None)
+    return {k: v for k, v in attrs.items() if v is not None}
 
 
 def _iris_cell_methods_to_str(cell_methods_obj):

xarray/core/alignment.py

@@ -341,10 +341,10 @@ def reindex_variables(
     for dim, indexer in indexers.items():
         if isinstance(indexer, DataArray) and indexer.dims != (dim,):
             warnings.warn(
-                "Indexer has dimensions {0:s} that are different "
-                "from that to be indexed along {1:s}. "
-                "This will behave differently in the future.".format(
-                    str(indexer.dims), dim),
+                "Indexer has dimensions {:s} that are different "
+                "from that to be indexed along {:s}. "
+                "This will behave differently in the future."
+                .format(str(indexer.dims), dim),
                 FutureWarning, stacklevel=3)
 
         target = new_indexes[dim] = utils.safe_cast_to_index(indexers[dim])

xarray/core/combine.py

@@ -41,9 +41,8 @@ def _infer_tile_ids_from_nested_list(entry, current_pos):
 
     if isinstance(entry, list):
         for i, item in enumerate(entry):
-            for result in _infer_tile_ids_from_nested_list(item,
-                                                           current_pos + (i,)):
-                yield result
+            yield from _infer_tile_ids_from_nested_list(
+                item, current_pos + (i,))
     else:
         yield current_pos, entry
 
@@ -735,10 +734,12 @@ def _auto_concat(datasets, dim=None, data_vars='all', coords='different',
             concat_dims = set(ds0.dims)
             if ds0.dims != ds1.dims:
                 dim_tuples = set(ds0.dims.items()) - set(ds1.dims.items())
-                concat_dims = set(i for i, _ in dim_tuples)
+                concat_dims = {i for i, _ in dim_tuples}
             if len(concat_dims) > 1:
-                concat_dims = set(d for d in concat_dims
-                                  if not ds0[d].equals(ds1[d]))
+                concat_dims = {
+                    d for d in concat_dims
+                    if not ds0[d].equals(ds1[d])
+                }
             if len(concat_dims) > 1:
                 raise ValueError('too many different dimensions to '
                                  'concatenate: %s' % concat_dims)

xarray/core/dataarray.py

@@ -1389,7 +1389,7 @@ def expand_dims(self, dim: Union[None, Hashable, Sequence[Hashable],
         elif isinstance(dim, Sequence) and not isinstance(dim, str):
             if len(dim) != len(set(dim)):
                 raise ValueError('dims should not contain duplicate values.')
-            dim = OrderedDict(((d, 1) for d in dim))
+            dim = OrderedDict((d, 1) for d in dim)
         elif dim is not None and not isinstance(dim, Mapping):
             dim = OrderedDict(((cast(Hashable, dim), 1),))