def mock_for_extract_field(self, fields, x=None, y=None):
"""
A context manager to ensure FF2PP._extract_field gets a field
instance looking like the next one in the "fields" iterable from
the "make_pp_field" call.
"""
with mock.patch("iris.fileformats._ff.FFHeader"):
ff2pp = ff.FF2PP("mock")
ff2pp._ff_header.lookup_table = [0, 0, len(fields)]
# Fake level constants, with shape specifying just one model-level.
ff2pp._ff_header.level_dependent_constants = np.zeros(1)
grid = mock.Mock()
grid.vectors = mock.Mock(return_value=(x, y))
ff2pp._ff_header.grid = mock.Mock(return_value=grid)
open_func = "builtins.open"
with mock.patch(
"iris.fileformats._ff._parse_binary_stream", return_value=[0]
), mock.patch(open_func), mock.patch(
"struct.unpack_from", return_value=[4]
), mock.patch(
"iris.fileformats.pp.make_pp_field", side_effect=fields
), mock.patch(
"iris.fileformats._ff.FF2PP._payload", return_value=(0, 0)
):
yield ff2pp
def mock_for_extract_field(self, fields, x=None, y=None):
"""
A context manager to ensure FF2PP._extract_field gets a field
instance looking like the next one in the "fields" iterable from
the "make_pp_field" call.
"""
with mock.patch('iris.fileformats._ff.FFHeader'):
ff2pp = ff.FF2PP('mock')
ff2pp._ff_header.lookup_table = [0, 0, len(fields)]
# Fake level constants, with shape specifying just one model-level.
ff2pp._ff_header.level_dependent_constants = np.zeros(1)
grid = mock.Mock()
grid.vectors = mock.Mock(return_value=(x, y))
ff2pp._ff_header.grid = mock.Mock(return_value=grid)
if six.PY3:
open_func = 'builtins.open'
else:
open_func = '__builtin__.open'
with mock.patch('numpy.fromfile', return_value=[0]), \
mock.patch(open_func), \
mock.patch('struct.unpack_from', return_value=[4]), \
mock.patch('iris.fileformats.pp.make_pp_field',
side_effect=fields), \
mock.patch('iris.fileformats._ff.FF2PP._payload',
return_value=(0, 0)):
yield ff2pp
def test_call_structure(self, _FFHeader):
# Check that the iter method calls the two necessary utility
# functions
extract_result = mock.Mock()
interpret_patch = mock.patch('iris.fileformats.pp._interpret_fields',
autospec=True, return_value=iter([]))
extract_patch = mock.patch('iris.fileformats._ff.FF2PP._extract_field',
autospec=True, return_value=extract_result)
FF2PP_instance = ff.FF2PP('mock')
with interpret_patch as interpret, extract_patch as extract:
list(iter(FF2PP_instance))
interpret.assert_called_once_with(extract_result)
extract.assert_called_once_with(FF2PP_instance)
def setUp(self):
self.filename = tests.get_data_path(("FF", "n48_multi_field"))
self.ff2pp = ff.FF2PP(self.filename)
self.ff_header = self.ff2pp._ff_header
data_shape = (73, 96)
delta = np.sin(np.linspace(0, np.pi * 5, data_shape[1])) * 5
lons = np.linspace(0, 180, data_shape[1]) + delta
lons = np.vstack([lons[:-1], lons[:-1] + 0.5 * np.diff(lons)]).T
lons = np.reshape(lons, lons.shape, order="F")
delta = np.sin(np.linspace(0, np.pi * 5, data_shape[0])) * 5
lats = np.linspace(-90, 90, data_shape[0]) + delta
lats = np.vstack([lats[:-1], lats[:-1] + 0.5 * np.diff(lats)]).T
lats = np.reshape(lats, lats.shape, order="F")
self.ff_header.column_dependent_constants = lons
self.ff_header.row_dependent_constants = lats
self.U_grid_x = lons[:-1, 1]
self.V_grid_y = lats[:-1, 1]
self.P_grid_x = lons[:, 0]
self.P_grid_y = lats[:, 0]
self.orig_make_pp_field = pp.make_pp_field
def new_make_pp_field(header):
field = self.orig_make_pp_field(header)
field.stash = self.ff2pp._custom_stash
field.bdx = field.bdy = field.bmdi
return field
# Replace the pp module function with this new function;
# this gets called in PP2FF.
pp.make_pp_field = new_make_pp_field
