update black version

.flake8

@@ -4,6 +4,8 @@
 #   https://flake8.readthedocs.io/en/latest/user/error-codes.html
 #   https://pycodestyle.readthedocs.io/en/latest/intro.html#error-codes
 
+max-line-length = 80
+select = C,E,F,W,B,B950
 ignore =
     # E203: whitespace before ':'
     E203,

.pre-commit-config.yaml

@@ -13,7 +13,7 @@ repos:
         # Don't commit to master branch.
     -   id: no-commit-to-branch
 -   repo: https://github.com/psf/black
-    rev: '19.10b0'
+    rev: '20.8b1'
     hooks:
     -   id: black
         # Force black to run on whole repo, using settings from pyproject.toml

docs/iris/gallery_code/general/plot_custom_file_loading.py

@@ -314,7 +314,9 @@ def main():
     # draw contour levels for the data (the top level is just a catch-all)
     levels = (0.0002, 0.002, 0.004, 1e10)
     cs = iplt.contourf(
-        cube, levels=levels, colors=("#80ffff", "#939598", "#e00404"),
+        cube,
+        levels=levels,
+        colors=("#80ffff", "#939598", "#e00404"),
     )
 
     # draw a black outline at the lowest contour to highlight affected areas

docs/iris/src/whatsnew/latest.rst

@@ -260,6 +260,9 @@ This document explains the changes made to Iris for this release
   `matplotlib.rcdefaults <https://matplotlib.org/3.1.1/api/matplotlib_configuration_api.html?highlight=rcdefaults#matplotlib.rcdefaults>`_,
   instead the tests will **always** use ``agg``. (:pull:`3846`)
 
+* `@bjlittle`_ migrated the `black`_ support from ``19.10b0`` to ``20.8b1``.
+  (:pull:`3866`)
+
 
 .. _Read the Docs: https://scitools-iris.readthedocs.io/en/latest/
 .. _Matplotlib: https://matplotlib.org/

lib/iris/_concatenate.py

@@ -161,7 +161,7 @@ def name(self):
         return self.defn.name()
 
 
-class _OtherMetaData(namedtuple("OtherMetaData", ["defn", "dims"],)):
+class _OtherMetaData(namedtuple("OtherMetaData", ["defn", "dims"])):
     """
     Container for the metadata that defines a cell measure or ancillary
     variable.

lib/iris/analysis/_area_weighted.py

@@ -55,8 +55,10 @@ def __init__(self, src_grid_cube, target_grid_cube, mdtol=1):
         self._mdtol = mdtol
 
         # Store regridding information
-        _regrid_info = eregrid._regrid_area_weighted_rectilinear_src_and_grid__prepare(
-            src_grid_cube, target_grid_cube
+        _regrid_info = (
+            eregrid._regrid_area_weighted_rectilinear_src_and_grid__prepare(
+                src_grid_cube, target_grid_cube
+            )
         )
         (
             src_x,

lib/iris/analysis/_regrid.py

@@ -480,11 +480,15 @@ def __call__(self, src):
         for slice_cube in src.slices(sx):
             if self._regrid_info is None:
                 # Calculate the basic regrid info just once.
-                self._regrid_info = _regrid_weighted_curvilinear_to_rectilinear__prepare(
-                    slice_cube, self.weights, self._target_cube
+                self._regrid_info = (
+                    _regrid_weighted_curvilinear_to_rectilinear__prepare(
+                        slice_cube, self.weights, self._target_cube
+                    )
+                )
+            slice_result = (
+                _regrid_weighted_curvilinear_to_rectilinear__perform(
+                    slice_cube, self._regrid_info
                 )
-            slice_result = _regrid_weighted_curvilinear_to_rectilinear__perform(
-                slice_cube, self._regrid_info
             )
             result_slices.append(slice_result)
         result = result_slices.merge_cube()

lib/iris/analysis/calculus.py

@@ -623,10 +623,14 @@ def curl(i_cube, j_cube, k_cube=None):
         #    (d/dtheta (i_cube * sin(lat)) - d_j_cube_dphi)
         # phi_cmpt = 1/r * ( d/dr (r * j_cube) - d_k_cube_dtheta)
         # theta_cmpt = 1/r * ( 1/cos(lat) * d_k_cube_dphi - d/dr (r * i_cube)
-        if y_coord.name() not in [
-            "latitude",
-            "grid_latitude",
-        ] or x_coord.name() not in ["longitude", "grid_longitude"]:
+        if (
+            y_coord.name()
+            not in [
+                "latitude",
+                "grid_latitude",
+            ]
+            or x_coord.name() not in ["longitude", "grid_longitude"]
+        ):
             raise ValueError(
                 "Expecting latitude as the y coord and "
                 "longitude as the x coord for spherical curl."

lib/iris/common/mixin.py

@@ -7,7 +7,6 @@
 
 from collections.abc import Mapping
 from functools import wraps
-import re
 
 import cf_units
 

lib/iris/common/resolve.py

@@ -37,7 +37,8 @@
 )
 
 _CategoryItems = namedtuple(
-    "CategoryItems", ["items_dim", "items_aux", "items_scalar"],
+    "CategoryItems",
+    ["items_dim", "items_aux", "items_scalar"],
 )
 
 _DimCoverage = namedtuple(
@@ -50,7 +51,8 @@
 _PreparedFactory = namedtuple("PreparedFactory", ["container", "dependencies"])
 
 _PreparedItem = namedtuple(
-    "PreparedItem", ["metadata", "points", "bounds", "dims", "container"],
+    "PreparedItem",
+    ["metadata", "points", "bounds", "dims", "container"],
 )
 
 _PreparedMetadata = namedtuple("PreparedMetadata", ["combined", "src", "tgt"])

lib/iris/cube.py

@@ -3647,8 +3647,8 @@ def __eq__(self, other):
 
             # having checked the metadata, now check the coordinates
             if result:
-                coord_compares = iris.analysis._dimensional_metadata_comparison(
-                    self, other
+                coord_compares = (
+                    iris.analysis._dimensional_metadata_comparison(self, other)
                 )
                 # if there are any coordinates which are not equal
                 result = not (
@@ -3658,7 +3658,7 @@ def __eq__(self, other):
 
             if result:
                 cm_compares = iris.analysis._dimensional_metadata_comparison(
-                    self, other, object_get=Cube.cell_measures,
+                    self, other, object_get=Cube.cell_measures
                 )
                 # if there are any cell measures which are not equal
                 result = not (
@@ -3668,7 +3668,7 @@ def __eq__(self, other):
 
             if result:
                 av_compares = iris.analysis._dimensional_metadata_comparison(
-                    self, other, object_get=Cube.ancillary_variables,
+                    self, other, object_get=Cube.ancillary_variables
                 )
                 # if there are any ancillary variables which are not equal
                 result = not (

lib/iris/fileformats/_ff.py

@@ -42,23 +42,23 @@
     ("model_version", (12,)),
     ("obs_file_type", (14,)),
     ("last_fieldop_type", (15,)),
-    ("first_validity_time", (21, 22, 23, 24, 25, 26, 27,)),
-    ("last_validity_time", (28, 29, 30, 31, 32, 33, 34,)),
-    ("misc_validity_time", (35, 36, 37, 38, 39, 40, 41,)),
-    ("integer_constants", (100, 101,)),
-    ("real_constants", (105, 106,)),
-    ("level_dependent_constants", (110, 111, 112,)),
-    ("row_dependent_constants", (115, 116, 117,)),
-    ("column_dependent_constants", (120, 121, 122,)),
-    ("fields_of_constants", (125, 126, 127,)),
-    ("extra_constants", (130, 131,)),
-    ("temp_historyfile", (135, 136,)),
-    ("compressed_field_index1", (140, 141,)),
-    ("compressed_field_index2", (142, 143,)),
-    ("compressed_field_index3", (144, 145,)),
-    ("lookup_table", (150, 151, 152,)),
+    ("first_validity_time", (21, 22, 23, 24, 25, 26, 27)),
+    ("last_validity_time", (28, 29, 30, 31, 32, 33, 34)),
+    ("misc_validity_time", (35, 36, 37, 38, 39, 40, 41)),
+    ("integer_constants", (100, 101)),
+    ("real_constants", (105, 106)),
+    ("level_dependent_constants", (110, 111, 112)),
+    ("row_dependent_constants", (115, 116, 117)),
+    ("column_dependent_constants", (120, 121, 122)),
+    ("fields_of_constants", (125, 126, 127)),
+    ("extra_constants", (130, 131)),
+    ("temp_historyfile", (135, 136)),
+    ("compressed_field_index1", (140, 141)),
+    ("compressed_field_index2", (142, 143)),
+    ("compressed_field_index3", (144, 145)),
+    ("lookup_table", (150, 151, 152)),
     ("total_prognostic_fields", (153,)),
-    ("data", (160, 161, 162,)),
+    ("data", (160, 161, 162)),
 ]
 
 # Offset value to convert from UM_FIXED_LENGTH_HEADER positions to

lib/iris/fileformats/cf.py

@@ -45,7 +45,7 @@
 # NetCDF variable attributes handled by the netCDF4 module and
 # therefore automatically classed as "used" attributes.
 _CF_ATTRS_IGNORE = set(
-    ["_FillValue", "add_offset", "missing_value", "scale_factor",]
+    ["_FillValue", "add_offset", "missing_value", "scale_factor"]
 )
 
 #: Supported dimensionless vertical coordinate reference surface/phemomenon

lib/iris/fileformats/name_loaders.py

@@ -489,7 +489,7 @@ def _generate_cubes(
                     circular = False
                 if coord.name == "flight_level":
                     icoord = DimCoord(
-                        points=pts, units=coord_units, long_name=long_name,
+                        points=pts, units=coord_units, long_name=long_name
                     )
                 else:
                     icoord = DimCoord(

lib/iris/fileformats/netcdf.py

@@ -1066,7 +1066,7 @@ def write(
             `chunksizes` and `endian` keywords are silently ignored for netCDF
             3 files that do not use HDF5.
 
-            """
+        """
         if unlimited_dimensions is None:
             unlimited_dimensions = []
 

lib/iris/fileformats/nimrod_load_rules.py

@@ -417,7 +417,7 @@ def coord_system(field, handle_metadata_errors):
                 "Plotting and reprojection may be impaired."
             )
         coord_sys = iris.coord_systems.TransverseMercator(
-            *crs_args, iris.coord_systems.GeogCS(**ellipsoid),
+            *crs_args, iris.coord_systems.GeogCS(**ellipsoid)
         )
     elif field.horizontal_grid_type == 1:
         coord_sys = iris.coord_systems.GeogCS(**ellipsoid)
@@ -456,7 +456,7 @@ def horizontal_grid(cube, field, handle_metadata_errors):
         dtype=np.float32,
     )
     x_coord = DimCoord(
-        points, standard_name=x_coord_name, units=units_name, coord_system=crs,
+        points, standard_name=x_coord_name, units=units_name, coord_system=crs
     )
     cube.add_dim_coord(x_coord, 1)
     points = np.linspace(
@@ -467,7 +467,7 @@ def horizontal_grid(cube, field, handle_metadata_errors):
         dtype=np.float32,
     )
     y_coord = DimCoord(
-        points, standard_name=y_coord_name, units=units_name, coord_system=crs,
+        points, standard_name=y_coord_name, units=units_name, coord_system=crs
     )
     cube.add_dim_coord(y_coord, 0)
 

lib/iris/fileformats/pp.py

@@ -105,10 +105,10 @@
     ("lbproj", (31,)),
     ("lbtyp", (32,)),
     ("lblev", (33,)),
-    ("lbrsvd", (34, 35, 36, 37,)),
+    ("lbrsvd", (34, 35, 36, 37)),
     ("lbsrce", (38,)),
-    ("lbuser", (39, 40, 41, 42, 43, 44, 45,)),
-    ("brsvd", (46, 47, 48, 49,)),
+    ("lbuser", (39, 40, 41, 42, 43, 44, 45)),
+    ("brsvd", (46, 47, 48, 49)),
     ("bdatum", (50,)),
     ("bacc", (51,)),
     ("blev", (52,)),
@@ -163,10 +163,10 @@
     ("lbproj", (31,)),
     ("lbtyp", (32,)),
     ("lblev", (33,)),
-    ("lbrsvd", (34, 35, 36, 37,)),
+    ("lbrsvd", (34, 35, 36, 37)),
     ("lbsrce", (38,)),
-    ("lbuser", (39, 40, 41, 42, 43, 44, 45,)),
-    ("brsvd", (46, 47, 48, 49,)),
+    ("lbuser", (39, 40, 41, 42, 43, 44, 45)),
+    ("brsvd", (46, 47, 48, 49)),
     ("bdatum", (50,)),
     ("bacc", (51,)),
     ("blev", (52,)),

lib/iris/plot.py

@@ -351,7 +351,7 @@ def _check_bounds_contiguity_and_mask(coord, data, atol=None, rtol=None):
             )
 
             not_masked_at_discontiguity_along_y = np.any(
-                np.logical_and(mask_invert[:-1,], diffs_along_y)
+                np.logical_and(mask_invert[:-1], diffs_along_y)
             )
 
             not_masked_at_discontiguity = (

lib/iris/tests/test_cdm.py

@@ -1135,7 +1135,7 @@ def assert_is_not_lazy(self, cube):
         self.assertFalse(cube.has_lazy_data())
 
     def test_slices(self):
-        lat_cube = next(self.cube.slices(["grid_latitude",]))
+        lat_cube = next(self.cube.slices(["grid_latitude"]))
         self.assert_is_lazy(lat_cube)
         self.assert_is_lazy(self.cube)
 
@@ -1459,7 +1459,7 @@ def test_coord_conversion(self):
 
         # List of string and unicode
         self.assertEqual(
-            len(cube._as_list_of_coords(["grid_longitude", "grid_latitude"],)),
+            len(cube._as_list_of_coords(["grid_longitude", "grid_latitude"])),
             2,
         )
 

lib/iris/tests/test_merge.py

@@ -1038,11 +1038,11 @@ def _makecube(self, y, cm=False, av=False):
         cube.add_aux_coord(iris.coords.DimCoord(y, long_name="y"))
         if cm:
             cube.add_cell_measure(
-                iris.coords.CellMeasure([1, 1], long_name="foo"), 0,
+                iris.coords.CellMeasure([1, 1], long_name="foo"), 0
             )
         if av:
             cube.add_ancillary_variable(
-                iris.coords.AncillaryVariable([1, 1], long_name="bar"), 0,
+                iris.coords.AncillaryVariable([1, 1], long_name="bar"), 0
             )
         return cube
 

lib/iris/tests/test_netcdf.py

@@ -425,25 +425,25 @@ def test_deferred_loading(self):
 
         # Consecutive tuple index on same dimension.
         self.assertCML(
-            cube[(0, 8, 4, 2, 14, 12),],
+            cube[((0, 8, 4, 2, 14, 12),)],
             ("netcdf", "netcdf_deferred_tuple_0.cml"),
         )
         self.assertCML(
-            cube[(0, 8, 4, 2, 14, 12),][(0, 2, 4, 1),],
+            cube[((0, 8, 4, 2, 14, 12),)][((0, 2, 4, 1),)],
             ("netcdf", "netcdf_deferred_tuple_1.cml"),
         )
-        subcube = cube[(0, 8, 4, 2, 14, 12),][(0, 2, 4, 1),][
+        subcube = cube[((0, 8, 4, 2, 14, 12),)][((0, 2, 4, 1),)][
             (1, 3),
         ]
         self.assertCML(subcube, ("netcdf", "netcdf_deferred_tuple_2.cml"))
 
         # Consecutive mixture on same dimension.
         self.assertCML(
-            cube[0:20:2][(9, 5, 8, 0),][3],
+            cube[0:20:2][((9, 5, 8, 0),)][3],
             ("netcdf", "netcdf_deferred_mix_0.cml"),
         )
         self.assertCML(
-            cube[(2, 7, 3, 4, 5, 0, 9, 10),][2:6][3],
+            cube[((2, 7, 3, 4, 5, 0, 9, 10),)][2:6][3],
             ("netcdf", "netcdf_deferred_mix_0.cml"),
         )
         self.assertCML(

lib/iris/tests/test_nimrod.py

@@ -73,7 +73,7 @@ def test_huge_field_load(self):
             "probability_fields",
         }:
             cube = iris.load(
-                tests.get_data_path(("NIMROD", "uk2km", "cutouts", datafile,))
+                tests.get_data_path(("NIMROD", "uk2km", "cutouts", datafile))
             )
             self.assertCML(cube, ("nimrod", f"{datafile}.cml"))
 
@@ -87,7 +87,7 @@ def test_load_kwarg(self):
             "Ellipsoid not supported, proj_biaxial_ellipsoid:-32767, horizontal_grid_type:0",
         ):
             with open(
-                tests.get_data_path(("NIMROD", "uk2km", "cutouts", datafile,)),
+                tests.get_data_path(("NIMROD", "uk2km", "cutouts", datafile)),
                 "rb",
             ) as infile:
                 iris.fileformats.nimrod_load_rules.run(

lib/iris/tests/test_pp_cf.py

@@ -87,9 +87,7 @@ def _test_file(self, name):
         else:
             fname_name = name
 
-        self.assertCML(
-            cubes, self._ref_dir + ("from_pp", fname_name + ".cml",)
-        )
+        self.assertCML(cubes, self._ref_dir + ("from_pp", fname_name + ".cml"))
 
         # 2) Save the Cube and check the netCDF
         nc_filenames = []

lib/iris/tests/unit/analysis/area_weighted/test_AreaWeightedRegridder.py

@@ -46,8 +46,10 @@ def extract_grid(self, cube):
     def check_mdtol(self, mdtol=None):
         src_grid, target_grid = self.grids()
         # Get _regrid_info result
-        _regrid_info = eregrid._regrid_area_weighted_rectilinear_src_and_grid__prepare(
-            src_grid, target_grid
+        _regrid_info = (
+            eregrid._regrid_area_weighted_rectilinear_src_and_grid__prepare(
+                src_grid, target_grid
+            )
         )
         self.assertEqual(len(_regrid_info), 9)
         with mock.patch(