Update dataset_plot.py

xarray/plot/dataset_plot.py

@@ -722,7 +722,7 @@ def _temp_dataarray(ds: Dataset, y: Hashable, locals_: dict[str, Any]) -> DataAr
     from xarray.core.dataarray import DataArray
 
     coords = dict(ds[y].coords)
-    dims = dict.fromkeys(ds[y].dims)
+    dims = set(ds[y].dims)
 
     # Add extra coords to the DataArray from valid kwargs, if using all
     # kwargs there is a risk that we add unnecessary dataarrays as
@@ -735,11 +735,10 @@ def _temp_dataarray(ds: Dataset, y: Hashable, locals_: dict[str, Any]) -> DataAr
         darray = ds.get(key)
         if darray is not None:
             coords[key] = darray
-            for d in darray.dims:
-                dims[d] = None
+            dims.update(darray.dims)
 
     # Trim dataset from unneccessary dims:
-    ds_trimmed = ds.drop_dims(ds.dims - dims.keys())
+    ds_trimmed = ds.drop_dims(ds.sizes.keys() - dims)  # TODO: Use ds.dims in the future
 
     # The dataarray has to include all the dims. Broadcast to that shape
     # and add the additional coords: