@hyanwong You're closer to this than I am - this seems like it should fix #1462. yes?

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 89.65%. Comparing base (ee8ccaa) to head (e49d5e7).
⚠️ Report is 1 commits behind head on main.

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I'm not sure. I think @daniel-goldstein suggested actually implementing the iterator in #1462 (comment) rather than making it bomb out.

It should be easy, it's just choosing either 1 or 2 from his list. Do you have a preference @benjeffery ?

Is what I've done here correct in that iterating .topologies makes sense?

Let's take the simple path here and raise an error rather than try to implement the right thing

Let's take the simple path here and raise an error rather than try to implement the right thing

Yes, my focus was on preventing the easy to trigger infinite loop.

@jeromekelleher Can I get a tick here? I don't think it is worth doing more than this, we just want to prevent infinite iteration.