Replace xarray.Dataset.dims with xarray.Dataset.sizes

This fixes a FutureWarning:

FutureWarning: The return type of `Dataset.dims` will be changed to return a set of dimension names in future, in order to be more consistent with `DataArray.dims`. To access a mapping from dimension names to lengths, please use `Dataset.sizes`.

tests/portprinter/test_port_printer_queue.py

@@ -48,9 +48,9 @@ def test_multiple_printers(tmpdir, with_two_components):
         assert os.path.isfile("air__density.nc")
         ds = xarray.open_dataset("air__density.nc", engine="h5netcdf")
         assert "air__density" in ds.variables
-        assert ds.dims["time"] == 5
+        assert ds.sizes["time"] == 5
 
         assert os.path.isfile("glacier_top_surface__slope.nc")
         ds = xarray.open_dataset("glacier_top_surface__slope.nc", engine="h5netcdf")
         assert "glacier_top_surface__slope" in ds.variables
-        assert ds.dims["time"] == 5
+        assert ds.sizes["time"] == 5

tests/printers/nc/test_database.py

@@ -46,9 +46,9 @@ def test_2d_constant_shape(tmpdir):
         assert set(root.dims) == {"y", "x", "time"}
         assert set(root.data_vars) == {"mesh", "Elevation"}
 
-        assert root.dims["x"] == 3
-        assert root.dims["y"] == 2
-        assert root.dims["time"] == 2
+        assert root.sizes["x"] == 3
+        assert root.sizes["y"] == 2
+        assert root.sizes["time"] == 2
 
         assert root.variables["Elevation"].shape == (2, 2, 3)
 
@@ -105,9 +105,9 @@ def test_2d_changing_shape(tmpdir):
         assert set(root.dims) == {"y", "x", "time"}
         assert set(root.data_vars) == {"mesh", "Temperature"}
 
-        assert root.dims["x"] == 3
-        assert root.dims["y"] == 3
-        assert root.dims["time"] == 1
+        assert root.sizes["x"] == 3
+        assert root.sizes["y"] == 3
+        assert root.sizes["time"] == 1
 
         assert root.data_vars["Temperature"].shape == (1, 3, 3)
         assert root.data_vars["Temperature"][0].data == approx(