Fixes.

lib/iris/experimental/ugrid/load.py

@@ -8,9 +8,6 @@
 Extensions to Iris' NetCDF loading to allow the construction of
 :class:`~iris.experimental.ugrid.mesh.Mesh`\\ es from UGRID data in the file.
 
-Eventual destination: :mod:`iris.fileformats.netcdf` (plan to split that module
-into ``load`` and ``save`` in future).
-
 """
 from contextlib import contextmanager
 from itertools import groupby
@@ -19,8 +16,8 @@
 
 from ...config import get_logger
 from ...coords import AuxCoord
-from ...fileformats import netcdf
 from ...fileformats._nc_load_rules.helpers import get_attr_units, get_names
+from ...fileformats.netcdf import loader as nc_loader
 from ...io import decode_uri, expand_filespecs
 from ...util import guess_coord_axis
 from .cf import (
@@ -202,7 +199,7 @@ def load_meshes(uris, var_name=None):
             else:
                 handling_format_spec = FORMAT_AGENT.get_spec(source, None)
 
-            if handling_format_spec.handler == netcdf.load_cubes:
+            if handling_format_spec.handler == nc_loader.load_cubes:
                 valid_sources.append(source)
             else:
                 message = f"Ignoring non-NetCDF file: {source}"
@@ -239,7 +236,7 @@ def _build_aux_coord(coord_var, file_path):
     assert isinstance(coord_var, CFUGridAuxiliaryCoordinateVariable)
     attributes = {}
     attr_units = get_attr_units(coord_var, attributes)
-    points_data = netcdf._get_cf_var_data(coord_var, file_path)
+    points_data = nc_loader._get_cf_var_data(coord_var, file_path)
 
     # Bounds will not be loaded:
     # Bounds may be present, but the UGRID conventions state this would
@@ -293,7 +290,7 @@ def _build_connectivity(connectivity_var, file_path, element_dims):
     assert isinstance(connectivity_var, CFUGridConnectivityVariable)
     attributes = {}
     attr_units = get_attr_units(connectivity_var, attributes)
-    indices_data = netcdf._get_cf_var_data(connectivity_var, file_path)
+    indices_data = nc_loader._get_cf_var_data(connectivity_var, file_path)
 
     cf_role = connectivity_var.cf_role
     start_index = connectivity_var.start_index
@@ -462,7 +459,7 @@ def _build_mesh(cf, mesh_var, file_path):
     )
     mesh_elements = filter(None, mesh_elements)
     for iris_object in mesh_elements:
-        netcdf._add_unused_attributes(
+        nc_loader._add_unused_attributes(
             iris_object, cf.cf_group[iris_object.var_name]
         )
 

lib/iris/fileformats/_nc_load_rules/helpers.py

@@ -31,9 +31,9 @@
 import iris.fileformats.netcdf
 from iris.fileformats.netcdf import (
     UnknownCellMethodWarning,
-    _get_cf_var_data,
     parse_cell_methods,
 )
+from iris.fileformats.netcdf.loader import _get_cf_var_data
 import iris.std_names
 import iris.util
 

lib/iris/tests/unit/fileformats/netcdf/test__FillValueMaskCheckAndStoreTarget.py

@@ -17,7 +17,7 @@
 
 import numpy as np
 
-from iris.fileformats.netcdf import _FillValueMaskCheckAndStoreTarget
+from iris.fileformats.netcdf.saver import _FillValueMaskCheckAndStoreTarget
 
 
 class Test__FillValueMaskCheckAndStoreTarget(tests.IrisTest):

lib/iris/tests/unit/fileformats/netcdf/test__get_cf_var_data.py

@@ -16,7 +16,7 @@
 
 from iris._lazy_data import _optimum_chunksize
 import iris.fileformats.cf
-from iris.fileformats.netcdf import _get_cf_var_data
+from iris.fileformats.netcdf.loader import _get_cf_var_data
 
 
 class Test__get_cf_var_data(tests.IrisTest):

lib/iris/tests/unit/fileformats/netcdf/test__load_aux_factory.py

@@ -16,7 +16,7 @@
 
 from iris.coords import DimCoord
 from iris.cube import Cube
-from iris.fileformats.netcdf import _load_aux_factory
+from iris.fileformats.netcdf.loader import _load_aux_factory
 
 
 class TestAtmosphereHybridSigmaPressureCoordinate(tests.IrisTest):

lib/iris/tests/unit/fileformats/netcdf/test__load_cube.py

@@ -15,7 +15,7 @@
 
 from iris.coords import DimCoord
 import iris.fileformats.cf
-from iris.fileformats.netcdf import _load_cube
+from iris.fileformats.netcdf.loader import _load_cube
 
 
 class TestCoordAttributes(tests.IrisTest):
@@ -28,7 +28,7 @@ def _patcher(engine, cf, cf_group):
         engine.cube_parts["coordinates"] = coordinates
 
     def setUp(self):
-        this = "iris.fileformats.netcdf._assert_case_specific_facts"
+        this = "iris.fileformats.netcdf.loader._assert_case_specific_facts"
         patch = mock.patch(this, side_effect=self._patcher)
         patch.start()
         self.addCleanup(patch.stop)
@@ -112,7 +112,7 @@ def test_flag_pass_thru_multi(self):
 
 class TestCubeAttributes(tests.IrisTest):
     def setUp(self):
-        this = "iris.fileformats.netcdf._assert_case_specific_facts"
+        this = "iris.fileformats.netcdf.loader._assert_case_specific_facts"
         patch = mock.patch(this)
         patch.start()
         self.addCleanup(patch.stop)

lib/iris/tests/unit/fileformats/netcdf/test__translate_constraints_to_var_callback.py

@@ -13,7 +13,9 @@
 
 import iris
 from iris.fileformats.cf import CFDataVariable
-from iris.fileformats.netcdf import _translate_constraints_to_var_callback
+from iris.fileformats.netcdf.loader import (
+    _translate_constraints_to_var_callback,
+)
 
 # import iris tests first so that some things can be initialised before
 # importing anything else

lib/iris/tests/unit/fileformats/netcdf/test_save.py

@@ -143,7 +143,7 @@ def test_None(self):
         # Test that when no fill_value argument is passed, the fill_value
         # argument to Saver.write is None or not present.
         cubes = self._make_cubes()
-        with mock.patch("iris.fileformats.netcdf.Saver") as Saver:
+        with mock.patch("iris.fileformats.netcdf.saver.Saver") as Saver:
             save(cubes, "dummy.nc")
 
         # Get the Saver.write mock
@@ -161,7 +161,7 @@ def test_single(self):
         # that value is passed to each call to Saver.write
         cubes = self._make_cubes()
         fill_value = 12345.0
-        with mock.patch("iris.fileformats.netcdf.Saver") as Saver:
+        with mock.patch("iris.fileformats.netcdf.saver.Saver") as Saver:
             save(cubes, "dummy.nc", fill_value=fill_value)
 
         # Get the Saver.write mock
@@ -178,7 +178,7 @@ def test_multiple(self):
         # each element is passed to separate calls to Saver.write
         cubes = self._make_cubes()
         fill_values = [123.0, 456.0, 789.0]
-        with mock.patch("iris.fileformats.netcdf.Saver") as Saver:
+        with mock.patch("iris.fileformats.netcdf.saver.Saver") as Saver:
             save(cubes, "dummy.nc", fill_value=fill_values)
 
         # Get the Saver.write mock
@@ -195,7 +195,7 @@ def test_single_string(self):
         # that value is passed to calls to Saver.write
         cube = Cube(["abc", "def", "hij"])
         fill_value = "xyz"
-        with mock.patch("iris.fileformats.netcdf.Saver") as Saver:
+        with mock.patch("iris.fileformats.netcdf.saver.Saver") as Saver:
             save(cube, "dummy.nc", fill_value=fill_value)
 
         # Get the Saver.write mock
@@ -211,7 +211,7 @@ def test_multi_wrong_length(self):
         # is passed as the fill_value argument, an error is raised
         cubes = self._make_cubes()
         fill_values = [1.0, 2.0, 3.0, 4.0]
-        with mock.patch("iris.fileformats.netcdf.Saver"):
+        with mock.patch("iris.fileformats.netcdf.saver.Saver"):
             with self.assertRaises(ValueError):
                 save(cubes, "dummy.nc", fill_value=fill_values)