Fixed flake8 gitlab error (landlab#1512)

* update the pre-commit flake8 hook

* remove comprehension lint

* add flake8-comprehension to hook

* add news fragments

* remove some additional lint from the tests folder

.pre-commit-config.yaml

@@ -21,11 +21,16 @@ repos:
     require_serial: true
     types_or: [python, pyi, jupyter]
     additional_dependencies: [".[jupyter]"]
-- repo: https://gitlab.com/pycqa/flake8
-  rev: 3.9.2
+
+- repo: https://github.com/pycqa/flake8
+  rev: 4.0.1
   hooks:
-  - id: flake8
-    # additional_dependencies: [flake8-bugbear]
+    - id: flake8
+      additional_dependencies:
+      - flake8-comprehensions
+      # - flake8-bugbear
+      #   - flake8-simplify
+
 - repo: https://gitlab.com/iamlikeme/nbhooks
   rev: 1.0.0
   hooks:

landlab/bmi/standard_names.py

@@ -58,4 +58,4 @@
 }
 
 
-LANDLAB_NAME = dict((value, key) for key, value in STANDARD_NAME.items() if key)
+LANDLAB_NAME = {value: key for key, value in STANDARD_NAME.items() if key}

landlab/cmd/landlab.py

@@ -151,7 +151,7 @@ def grids(ctx):
     verbose = ctx.parent.parent.params["verbose"]
     silent = ctx.parent.parent.params["silent"]
 
-    index = dict(grids={})
+    index = {"grids": {}}
     for cls in GRIDS:
         index["grids"][cls.__name__] = _categorize_class(cls)
         index["grids"][cls.__name__]["field-io"] += [
@@ -199,7 +199,7 @@ def components(ctx):
 
     from sphinx.util.docstrings import prepare_docstring
 
-    index = dict(components={})
+    index = {"components": {}}
     for cls in get_all_components():
         if verbose and not silent:
             out(f"indexing: {cls.__name__}")

landlab/components/flexure/funcs.py

@@ -126,7 +126,7 @@ def subside_point_load(load, loc, coords, params=None, out=None):
     >>> print(round(dz.max(), 9) / 2.)
     5.265e-07
     """
-    params = params or dict(eet=6500.0, youngs=7.0e10)
+    params = params or {"eet": 6500.0, "youngs": 7.0e10}
     eet, youngs = params["eet"], params["youngs"]
     gamma_mantle = params.get("gamma_mantle", 33000.0)
 

landlab/components/flow_accum/flow_accum_to_n.py

@@ -75,7 +75,7 @@ def __init__(self, delta, D, num_receivers):
         """
 
         self.num_receivers = num_receivers
-        self.s = list()
+        self.s = []
         self.delta = delta
         self.D = D
 
@@ -135,7 +135,7 @@ def construct__stack(self, nodes):
         try:
             base = set(nodes)
         except TypeError:
-            base = set([nodes])
+            base = {nodes}
 
         # instantiate the time keeping variable i, and a variable to keep track
         # of the visit time. Using visit time allows us to itterate through
@@ -151,7 +151,7 @@ def construct__stack(self, nodes):
         num_visits[list(base)] += 1
 
         i = 1
-        visited = set([])
+        visited = set()
         for node_i in base:
             # select the nodes to visit
             visit = set(self.D[self.delta[node_i] : self.delta[node_i + 1]])
@@ -177,8 +177,8 @@ def construct__stack(self, nodes):
             # increase counter
             i += 1
 
-            visited = set([])
-            new_completes = set([])
+            visited = set()
+            new_completes = set()
 
             for node_i in completed:
 

landlab/components/lake_fill/lake_fill_barnes.py

@@ -684,7 +684,7 @@ def _fill_to_flat_with_tracking(
         >>> out == {8: deque([7]), 16: deque([15, 9, 14, 22])}
         True
         """
-        lakemappings = dict()
+        lakemappings = {}
         outlet_ID = self._grid.BAD_INDEX
         while True:
             try:
@@ -887,7 +887,7 @@ def _fill_to_slant_with_optional_tracking(
         ...           'ignore_overfill flag at component instantiation.')
         ValueError was raised: Pit is overfilled due to creation of two outlets as the minimum gradient gets applied. Suppress this Error with the ignore_overfill flag at component instantiation.
         """
-        lakemappings = dict()
+        lakemappings = {}
         outlet_ID = self._grid.BAD_INDEX
         while True:
             try:

landlab/components/pet/potential_evapotranspiration_field.py

@@ -2,7 +2,7 @@
 
 from landlab import Component
 
-_VALID_METHODS = set(["Constant", "PriestleyTaylor", "MeasuredRadiationPT", "Cosine"])
+_VALID_METHODS = {"Constant", "PriestleyTaylor", "MeasuredRadiationPT", "Cosine"}
 
 
 def _assert_method_is_valid(method):

landlab/components/plant_competition_ca/plant_competition_ca.py

@@ -2,7 +2,7 @@
 
 from landlab import Component
 
-_VALID_METHODS = set(["Grid"])
+_VALID_METHODS = {"Grid"}
 GRASS = 0
 SHRUB = 1
 TREE = 2

landlab/components/radiation/radiation.py

@@ -2,7 +2,7 @@
 
 from landlab import Component
 
-_VALID_METHODS = set(["Grid"])
+_VALID_METHODS = {"Grid"}
 
 
 def _assert_method_is_valid(method):

landlab/components/soil_moisture/soil_moisture_dynamics.py

@@ -2,7 +2,7 @@
 
 from landlab import Component
 
-_VALID_METHODS = set(["Grid", "Multi"])
+_VALID_METHODS = {"Grid", "Multi"}
 
 
 def assert_method_is_valid(method):

landlab/components/vegetation_dynamics/vegetation_dynamics.py

@@ -2,7 +2,7 @@
 
 from landlab import Component
 
-_VALID_METHODS = set(["Grid"])
+_VALID_METHODS = {"Grid"}
 
 
 def assert_method_is_valid(method):

landlab/graph/graph.py

@@ -211,7 +211,7 @@ def thaw(self):
         self._frozen = False
 
     def _add_variable(self, name, var, dims=None, attrs=None):
-        kwds = dict(data=var, dims=dims, attrs=attrs)
+        kwds = {"data": var, "dims": dims, "attrs": attrs}
         self.ds.update({name: xr.DataArray(**kwds)})
         if self._frozen:
             self.freeze()

landlab/grid/base.py

@@ -454,7 +454,7 @@ def fields(self, include="*", exclude=None):
         if isinstance(exclude, str):
             exclude = [exclude]
 
-        layer_groups = set(["_".join(["layer", at]) for at in self.groups])
+        layer_groups = {"_".join(["layer", at]) for at in self.groups}
         layer_groups.add("layer")
 
         canonical_names = set()

landlab/grid/create.py

@@ -114,9 +114,10 @@ def add_field_from_function(grid, name, functions, at="node"):
     ModelGrid
         The grid with the new field.
     """
-    valid_functions = set(_SYNTHETIC_FIELD_CONSTRUCTORS) | set(
-        ["read_esri_ascii", "read_netcdf"]
-    )
+    valid_functions = set(_SYNTHETIC_FIELD_CONSTRUCTORS) | {
+        "read_esri_ascii",
+        "read_netcdf",
+    }
 
     for func_name, func_args in as_list_of_tuples(functions):
         if func_name not in valid_functions:

landlab/io/esri_ascii.py

@@ -231,7 +231,7 @@ def _header_is_valid(header):
         The header has the key but its values is of the wrong type.
     """
     header_keys = set(header)
-    required_keys = set(["ncols", "nrows", "cellsize"])
+    required_keys = {"ncols", "nrows", "cellsize"}
 
     if not required_keys.issubset(header_keys):
         raise MissingRequiredKeyError(", ".join(required_keys - header_keys))
@@ -336,7 +336,7 @@ def read_asc_header(asc_file):
     Traceback (most recent call last):
     KeyTypeError: Unable to convert nrows to <type 'int'>
     """
-    header = dict()
+    header = {}
     for (key, value) in _header_lines(asc_file):
         header[key] = value
 

landlab/io/netcdf/dump.py

@@ -131,13 +131,11 @@ def to_netcdf(
 
 def _add_time_dimension_to_dataset(dataset, time=0.0):
     """Add a time dimension to all variables except those at_layer."""
-    names = set(
-        [
-            name
-            for name in dataset.variables
-            if name.startswith("at_") and not name.startswith("at_layer")
-        ]
-    )
+    names = {
+        name
+        for name in dataset.variables
+        if name.startswith("at_") and not name.startswith("at_layer")
+    }
 
     for name in names:
         dataset[name] = (("time",) + dataset[name].dims, dataset[name].values[None])

landlab/io/netcdf/read.py

@@ -177,7 +177,7 @@ def _read_netcdf_structured_data(root):
         Data values, reshaped to match that of the grid. Keys are the
         variable names as read from the NetCDF file.
     """
-    fields = dict()
+    fields = {}
     grid_mapping_exists = False
     grid_mapping_dict = None
     for (name, var) in root.variables.items():

landlab/io/netcdf/write.py

@@ -91,7 +91,7 @@ def _get_dimension_sizes(shape):
     """
     names = _AXIS_DIMENSION_NAMES[-1 : -(len(shape) + 1) : -1]
 
-    sizes = dict()
+    sizes = {}
     for (axis, name) in enumerate(names):
         sizes[name] = shape[-(axis + 1)]
 
@@ -530,9 +530,12 @@ def _set_netcdf_grid_mapping_variable(root, grid_mapping):
         setattr(var, attr, grid_mapping[attr])
 
 
-_VALID_NETCDF_FORMATS = set(
-    ["NETCDF3_CLASSIC", "NETCDF3_64BIT", "NETCDF4_CLASSIC", "NETCDF4"]
-)
+_VALID_NETCDF_FORMATS = {
+    "NETCDF3_CLASSIC",
+    "NETCDF3_64BIT",
+    "NETCDF4_CLASSIC",
+    "NETCDF4",
+}
 
 
 def _guess_at_location(fields, names):

landlab/io/shapefile/read_shapefile.py

@@ -258,10 +258,10 @@ def read_shapefile(
 
     sf = _read_shapefile(file, dbf)
 
-    link_field_conversion = link_field_conversion or dict()
-    node_field_conversion = node_field_conversion or dict()
-    link_field_dtype = link_field_dtype or dict()
-    node_field_dtype = node_field_dtype or dict()
+    link_field_conversion = link_field_conversion or {}
+    node_field_conversion = node_field_conversion or {}
+    link_field_dtype = link_field_dtype or {}
+    node_field_dtype = node_field_dtype or {}
 
     if sf.shapeTypeName != "POLYLINE":
         raise ValueError(

landlab/layers/eventlayers.py

@@ -528,7 +528,7 @@ def __init__(self, number_of_stacks, allocated=0):
         self._number_of_layers = 0
         self._number_of_stacks = number_of_stacks
         self._surface_index = np.zeros(number_of_stacks, dtype=int)
-        self._attrs = dict()
+        self._attrs = {}
 
         dims = (self.number_of_layers, self.number_of_stacks)
         self._attrs["_dz"] = np.empty(dims, dtype=float)

landlab/plot/imshow.py

@@ -304,7 +304,7 @@ def _imshow_grid_values(
             + grid.xy_of_lower_left[0]
         )
 
-        kwds = dict(cmap=cmap)
+        kwds = {"cmap": cmap}
         (kwds["vmin"], kwds["vmax"]) = (values.min(), values.max())
         if (limits is None) and ((vmin is None) and (vmax is None)):
             if symmetric_cbar:

landlab/plot/imshowhs.py

@@ -445,9 +445,13 @@ def _imshowhs_grid_values(
 
     # Poperties of bounding box of colorbar label, if used:
     if add_label_bbox:
-        bbox_prop = dict(
-            boxstyle="round", pad=0.1, facecolor="white", alpha=0.7, edgecolor="white"
-        )
+        bbox_prop = {
+            "boxstyle": "round",
+            "pad": 0.1,
+            "facecolor": "white",
+            "alpha": 0.7,
+            "edgecolor": "white",
+        }
     else:
         bbox_prop = None
 
@@ -501,7 +505,7 @@ def _imshowhs_grid_values(
         blend_modes = ["hsv", "overlay", "soft"]
         if plot_type == "DEM":
 
-            kwds = dict(cmap=cmap)
+            kwds = {"cmap": cmap}
             (kwds["vmin"], kwds["vmax"]) = (values.min(), values.max())
             if (limits is None) and ((vmin is None) and (vmax is None)):
                 if symmetric_cbar:
@@ -566,7 +570,7 @@ def _imshowhs_grid_values(
                 shape = (-1,)
             val1 = values_at_node_drape1.reshape(shape)
 
-            kwds = dict(cmap=cmap)
+            kwds = {"cmap": cmap}
             (kwds["vmin"], kwds["vmax"]) = (val1.min(), val1.max())
             if (limits is None) and ((vmin is None) and (vmax is None)):
                 if symmetric_cbar:
@@ -699,7 +703,7 @@ def _imshowhs_grid_values(
 
                 if cmap2 is None:
                     cmap2 = plt.cm.terrain
-                kwds = dict(cmap=cmap2)
+                kwds = {"cmap": cmap2}
                 (kwds["vmin"], kwds["vmax"]) = (val2.min(), val2.max())
                 if (limits is None) and ((vmin is None) and (vmax is None)):
                     if symmetric_cbar:

landlab/utils/decorators.py

@@ -70,7 +70,7 @@ def _wrapped(grid):
                 ds = grid
 
             if name not in ds:
-                setattr(grid, self._dataset, ds.update(dict(name=func(grid))))
+                setattr(grid, self._dataset, ds.update({"name": func(grid)}))
 
             return getattr(grid, self._dataset)[name].values
 

news/1512.misc

@@ -0,0 +1,3 @@
+
+Fixed a broken *pre-commit* hook that caused an error when checking for lint
+with *flake8*.

news/1512.misc.1

@@ -0,0 +1,3 @@
+
+Added *flake8-comprehension* to the *flake8* *pre-commit* hook to identify
+comprehension-related lint.

notebooks/conftest.py

@@ -9,7 +9,7 @@
 def collect_notebooks(src):
     p = pathlib.Path(src)
     if p.is_dir():
-        return set([_p.absolute() for _p in iter_notebooks_in_dir(p, src)])
+        return {_p.absolute() for _p in iter_notebooks_in_dir(p, src)}
     else:
         raise ValueError("{0}: not a directory".format(src))
 

notebooks/run_notebook_checks.py

@@ -13,9 +13,9 @@
 def collect_notebooks(src):
     p = pathlib.Path(src)
     if p.is_dir():
-        return set([_p.absolute() for _p in iter_notebooks_in_dir(p, src)])
+        return {_p.absolute() for _p in iter_notebooks_in_dir(p, src)}
     elif is_a_notebook(p):
-        return set([p.absolute()])
+        return {p.absolute()}
     else:
         raise ValueError("{0}: not a directory or a notebook".format(src))