misc: consider datasources filtered on user as existing (#68189)

tests/test_formdef_import.py

@@ -426,6 +426,13 @@ def test_unknown_data_source(pub):
     with pytest.raises(FormdefImportError):
         FormDef.import_from_xml(io.BytesIO(export))
 
+    # cards filtered on user
+    formdef.fields = [
+        fields.StringField(id='1', type='string', data_source={'type': 'carddef:foo:_with_user_filter'})
+    ]
+    export = ET.tostring(export_to_indented_xml(formdef))
+    FormDef.import_from_xml(io.BytesIO(export))
+
     # carddef custom view as datasource
     pub.custom_view_class.wipe()
     custom_view = pub.custom_view_class()

wcs/formdef.py

@@ -1566,7 +1566,7 @@ class FormDef(StorableObject):
                             unknown_datasources.add(data_source_id)
                             continue
 
-                        if len(parts) == 2:
+                        if len(parts) == 2 or parts[2] == '_with_user_filter':
                             continue
 
                         lookup_criterias = [