Doubly nested array subfield infers `never` for value type about form HOT 8 CLOSED

What's happening here is that, while our types are correct - they are extremely complex. Complex enough that we have to add an edgecase for only calculating a specific depth (in our case, 3 deep) so that TypeScript doesn't break.

This string is reading that 3-level depth and therefore breaking.

Tagging in our type-level perf expert @tannerlinsley to see if we can get together to investigate a potential fix

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I’ll take a look

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@chorobin might even be a better fit here. He knows way more about perf

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Looking briefly I can see a few things that could be more efficient. I don't think these types are tail recursive optimised, is this why TS was breaking and you had to add a depth limit? Usually there's a recursive limit up to 100 with non-optimised and 1000 optimised.

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If the depth limit can be modified (by manually adding types to extend it or otherwise), then it might make sense to choose a limit that is far beyond what could be reasonably expected for the form state, like 10 or so.

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@chorobin the reason we limited depth was due to TS seemingly running into OOM problems without it. Help debugging would be immensely helpful

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Do we have a reproducer of the OOM errors?

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Confirmed to be fixed by #680! Thanks @chorobin 😄😄😄

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