bugfix

Author: dcherian

xarray/core/dataset.py

@@ -3032,12 +3032,13 @@ def _rename_all(self, name_dict, dims_dict):
         # in this case, convert to IndexVariable and set indexes
         # GH4107
         for name in set(self.dims):
-            indexvar = variables.pop(name).to_index_variable()
-            variables[name] = indexvar
-            if indexes is None:
-                indexes = dict()
-            indexes[name] = indexvar.to_index()
-            coord_names.add(name)
+            if name in variables:
+                indexvar = variables.pop(name).to_index_variable()
+                variables[name] = indexvar
+                if indexes is None:
+                    indexes = dict()
+                indexes[name] = indexvar.to_index()
+                coord_names.add(name)
 
         return variables, coord_names, dims, indexes