Autocomplete breaks after one property for an array generic about typescript

[Andarist]

If you don't need to infer queries then this works reasonably well: TS playground

[RareSecond]

Amazing, this works super smooth! Notice for further readers: the correct typing of the tuple will only work on TypeScript >5.4.

If you would have some spare time, could you explain the differences and why your approach is better?

[Andarist]

With a small adjustment you can also make it work with TS 5.3: TS playground

If you would have some spare time, could you explain the differences and why your approach is better?

I think it's better because it gives you a clear way of relating "positional inferences". The query type depends on its own sibling model - you don't even have to create a discriminated union to achieve this. So it's more flexible because you can introduce such dependencies with unknown constraints.

I don't know why the autocompletes work in this particular way on your two first examples. This might be worth investigating or something. I know though that often autocompletes in objects for optional properties etc might stop working in inference contexts. The problem is that the inferred type (like even {}) is already valid at a particular position and TS sees that type there and not the original constraint based on which it was inferred. So there is no source from which those properties could be obtained. There are some internal ways to query those types with different flags so the constraint can actually often be obtained in such positions but not every call site is querying completions from both types (with inference enabled and with inference blocked on the source location).