Portable comparisons (for sorting)

lib/iris/_concatenate.py

@@ -279,7 +279,11 @@ def concatenate(cubes, error_on_mismatch=False):
     # Construct a concatenated cube from each of the proto-cubes.
     concatenated_cubes = iris.cube.CubeList()
 
-    for name in sorted(proto_cubes_by_name):
+    # Emulate Python 2 behaviour.
+    def _none_sort(item):
+        return (item is not None, item)
+
+    for name in sorted(proto_cubes_by_name, key=_none_sort):
         for proto_cube in proto_cubes_by_name[name]:
             # Construct the concatenated cube.
             concatenated_cubes.append(proto_cube.concatenate())

lib/iris/_merge.py

@@ -24,6 +24,7 @@
 
 from __future__ import (absolute_import, division, print_function)
 from six.moves import (filter, input, map, range, zip)  # noqa
+import six
 
 from collections import namedtuple, OrderedDict
 from copy import deepcopy
@@ -1300,7 +1301,8 @@ def _define_space(self, space, positions, indexes, function_matrix):
         def axis_and_name(name):
             axis_dict = {'T': 1, 'Z': 2, 'Y': 3, 'X': 4}
             axis_index = axis_dict.get(self._guess_axis(name), 0)
-            return (axis_index, name)
+            # The middle element ensures sorting is the same as Python 2.
+            return (axis_index, not isinstance(name, six.integer_types), name)
         names = sorted(space, key=axis_and_name)
         dim_by_name = {}
 

lib/iris/coords.py

@@ -64,6 +64,20 @@ def name(self, default='unknown'):
         """
         return self.standard_name or self.long_name or self.var_name or default
 
+    def __lt__(self, other):
+        if not isinstance(other, CoordDefn):
+            return NotImplemented
+
+        def _sort_key(defn):
+            # Emulate Python 2 behaviour with None
+            return (defn.standard_name is not None, defn.standard_name,
+                    defn.long_name is not None, defn.long_name,
+                    defn.var_name is not None, defn.var_name,
+                    defn.units is not None, defn.units,
+                    defn.coord_system is not None, defn.coord_system)
+
+        return _sort_key(self) < _sort_key(other)
+
 
 class CoordExtent(collections.namedtuple('_CoordExtent', ['name_or_coord',
                                                           'minimum',

lib/iris/cube.py

@@ -452,9 +452,13 @@ def merge(self, unique=True):
                 proto_cube = iris._merge.ProtoCube(cube)
                 proto_cubes.append(proto_cube)
 
+        # Emulate Python 2 behaviour.
+        def _none_sort(item):
+            return (item is not None, item)
+
         # Extract all the merged cubes from the ProtoCubes.
         merged_cubes = CubeList()
-        for name in sorted(proto_cubes_by_name):
+        for name in sorted(proto_cubes_by_name, key=_none_sort):
             for proto_cube in proto_cubes_by_name[name]:
                 merged_cubes.extend(proto_cube.merge(unique=unique))
 

lib/iris/io/format_picker.py

@@ -211,17 +211,20 @@ def handler(self):
         """The handler function of this FileFormat. (Read only)"""
         return self._handler
 
+    def _sort_key(self):
+        return (-self.priority, self.name, self.file_element)
+
     def __lt__(self, other):
         if not isinstance(other, FormatSpecification):
             return NotImplemented
 
-        return (-self.priority, hash(self)) < (-other.priority, hash(other))
+        return self._sort_key() < other._sort_key()
 
     def __eq__(self, other):
         if not isinstance(other, FormatSpecification):
             return NotImplemented
 
-        return self.priority == other.priority and hash(self) == hash(other)
+        return self._sort_key() == other._sort_key()
 
     def __ne__(self, other):
         return not (self == other)

lib/iris/tests/results/file_load/known_loaders.txt

@@ -1,16 +1,16 @@
  * NetCDF OPeNDAP (priority 6)
  * NAME III (priority 5)
- * NetCDF_v4 (priority 5)
- * UM Post Processing file (PP) (priority 5)
  * NetCDF (priority 5)
  * NetCDF 64 bit offset format (priority 5)
+ * NetCDF_v4 (priority 5)
+ * UM Post Processing file (PP) (priority 5)
  * UM Fieldsfile (FF) post v5.2 (priority 4)
- * UM Fieldsfile (FF) pre v3.1 (priority 3)
- * UM Fieldsfile (FF) ancillary (priority 3)
- * UM Post Processing file (PP) little-endian (priority 3)
- * UM Fieldsfile (FF) converted with ieee to 32 bit (priority 3)
- * UM Fieldsfile (FF) ancillary converted with ieee to 32 bit (priority 3)
- * NIMROD (priority 3)
  * ABF (priority 3)
  * ABL (priority 3)
+ * NIMROD (priority 3)
+ * UM Fieldsfile (FF) ancillary (priority 3)
+ * UM Fieldsfile (FF) ancillary converted with ieee to 32 bit (priority 3)
+ * UM Fieldsfile (FF) converted with ieee to 32 bit (priority 3)
+ * UM Fieldsfile (FF) pre v3.1 (priority 3)
+ * UM Post Processing file (PP) little-endian (priority 3)
  * GRIB (priority 1)

lib/iris/tests/unit/fileformats/grib/load_rules/test_convert.py

@@ -96,7 +96,8 @@ def assert_bounded_message(self, **kwargs):
                       'edition': 1, '_forecastTime': 15,
                       '_forecastTimeUnit': 'hours',
                       'phenomenon_bounds': lambda u: (80, 120),
-                      '_phenomenonDateTime': -1}
+                      '_phenomenonDateTime': -1,
+                      'table2Version': 9999}
         attributes.update(kwargs)
         message = mock.Mock(**attributes)
         self._test_for_coord(message, convert, self.is_forecast_period,

lib/iris/tests/unit/fileformats/pp_rules/test__all_other_rules.py

@@ -118,9 +118,9 @@ def test_other_lbtim_ib(self):
         self.assertEqual(res, expected)
 
     def test_multiple_unordered_lbprocs(self):
-        field = mock.MagicMock(lbproc=192,
+        field = mock.MagicMock(lbproc=192, bzx=0, bdx=1, lbnpt=3, lbrow=3,
                                lbtim=mock.Mock(ia=24, ib=5, ic=3),
-                               lbcode=SplittableInt(1),
+                               lbcode=SplittableInt(1), x_bounds=None,
                                _x_coord_name=lambda: 'longitude',
                                _y_coord_name=lambda: 'latitude')
         res = _all_other_rules(field)[CELL_METHODS_INDEX]
@@ -129,9 +129,9 @@ def test_multiple_unordered_lbprocs(self):
         self.assertEqual(res, expected)
 
     def test_multiple_unordered_rotated_lbprocs(self):
-        field = mock.MagicMock(lbproc=192,
+        field = mock.MagicMock(lbproc=192, bzx=0, bdx=1, lbnpt=3, lbrow=3,
                                lbtim=mock.Mock(ia=24, ib=5, ic=3),
-                               lbcode=SplittableInt(101),
+                               lbcode=SplittableInt(101), x_bounds=None,
                                _x_coord_name=lambda: 'grid_longitude',
                                _y_coord_name=lambda: 'grid_latitude')
         res = _all_other_rules(field)[CELL_METHODS_INDEX]