Users aren't warned when relations have poorly implemented is_relation methods.

[ieaves]

The traverse_relation_graph, get_type_inference_path, and cast_to_inferred_type all implement a depth-first search algorithm returning the first childless node for which either the Series or transformed Series is of the same type as the node.

This algorithm implicitly assumes the is_relation method on a user defined relation is in fact unique. When the is_relation method is not unique we should warn the user somehow.

Ideas

• Run a suite of unit tests against the constructed graph upon construction looking for multiple matching types
• modify the search algorithm to look for multiple matches (much less efficient as it requires running many more is_relation and transform operations)
• others...?

[ieaves]

Solution #1

Run a suite of unit tests against the constructed graph upon construction looking for multiple matching types