Remove unneeded cube copies in tests

tests/operators/test_misc.py

@@ -30,15 +30,13 @@ def test_noop_operator():
 
 def test_remove_attribute_cube(cube):
     """Remove attribute from a Cube."""
-    cube = cube.copy()
     assert "STASH" in cube.attributes
     cube = misc.remove_attribute(cube, "STASH")[0]
     assert "STASH" not in cube.attributes
 
 
 def test_remove_attribute_cubelist(cubes):
     """Remove attribute from a CubeList."""
-    cubes = cubes.copy()
     for cube in cubes:
         assert "STASH" in cube.attributes
     cubes = misc.remove_attribute(cubes, "STASH")

tests/operators/test_plots.py

@@ -39,7 +39,6 @@ def test_check_single_cube():
 def test_spatial_contour_plot(cube, tmp_working_dir):
     """Plot spatial contour plot of instant air temp."""
     # Remove realization coord to increase coverage, and as its not needed.
-    cube = cube.copy()
     cube.remove_coord("realization")
     cube_2d = cube.slices_over("time").next()
     plot.spatial_contour_plot(cube_2d, filename="plot")
@@ -67,7 +66,6 @@ def test_postage_stamp_contour_plot(monkeypatch, tmp_path):
 def test_postage_stamp_contour_plot_sequence_coord_check(cube, tmp_working_dir):
     """Check error when cube has no time coordinate."""
     # What does this even physically mean? No data?
-    cube = cube.copy()
     cube.remove_coord("time")
     with pytest.raises(ValueError):
         plot.spatial_contour_plot(cube)

tests/operators/test_utils.py

@@ -19,19 +19,18 @@
 import CSET.operators._utils as operator_utils
 
 
-def test_missing_coord_get_cube_yxcoordname(regrid_rectilinear_cube):
-    """Missing coordinate raises error."""
-    # Missing X coordinate.
-    source = regrid_rectilinear_cube.copy()
-    source.remove_coord("longitude")
+def test_missing_coord_get_cube_yxcoordname_x(regrid_rectilinear_cube):
+    """Missing X coordinate raises error."""
+    regrid_rectilinear_cube.remove_coord("longitude")
     with pytest.raises(ValueError):
-        operator_utils.get_cube_yxcoordname(source)
+        operator_utils.get_cube_yxcoordname(regrid_rectilinear_cube)
 
-    # Missing Y coordinate.
-    source = regrid_rectilinear_cube.copy()
-    source.remove_coord("latitude")
+
+def test_missing_coord_get_cube_yxcoordname_y(regrid_rectilinear_cube):
+    """Missing Y coordinate raises error."""
+    regrid_rectilinear_cube.remove_coord("longitude")
     with pytest.raises(ValueError):
-        operator_utils.get_cube_yxcoordname(source)
+        operator_utils.get_cube_yxcoordname(regrid_rectilinear_cube)
 
 
 def test_get_cube_yxcoordname(regrid_rectilinear_cube):