bug fix: read the appropriate key of topologies

python/dolfinx/io/gmshio.py

@@ -269,20 +269,21 @@ def model_to_mesh(
 
         # Check that all cells are tagged once
         _d = model.getDimension()
-        if _d not in topologies.keys():
-            raise RuntimeError("All cells are expected to be tagged once; none found")
         _elementTypes, _elementTags, _nodeTags = model.mesh.getElements(dim=_d, tag=-1)
         # assert only one type of elements
         # assert len(_elementTypes) == 1  # NOTE: already checked in extract_topology_and_markers
+        _elementType_dim = _elementType[0]
+        if _elementType_dim not in topologies.keys():
+            raise RuntimeError("All cells are expected to be tagged once; none found")
         nbcells = len(_elementTags[0])
-        nbcells_tagged = len(topologies[_d]["entity_tags"])
+        nbcells_tagged = len(topologies[_elementType_dim]["entity_tags"])
         if nbcells != nbcells_tagged:
             e = (
                 "All cells are expected to be tagged once;"
                 f"found: {nbcells_tagged}, expected: {nbcells}"
             )
             raise RuntimeError(e)
-        nbcells_tagged_once = len(np.unique(topologies[_d]["entity_tags"]))
+        nbcells_tagged_once = len(np.unique(topologies[_elementType_dim]["entity_tags"]))
         if nbcells_tagged != nbcells_tagged_once:
             e = "All cells are expected to be tagged once; found duplicates"
             raise RuntimeError(e)