Generate kind-correct wildcards when selecting from a wildcard #17025
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Previously, derivedSelect would incorrectly approximate `fn.R` by `? >: Nothing <: Any` in `i16997.min.scala`, which subsequently lead to a kind-incorrect type application `Any[Y]` that broke type inference. scala#16999 proposed to fix this by changing type inference, but it seems like we don't need to do that if we make sure our wildcards are always kind-correct. Note that the wildcard logic in lookupRefined could be removed: it seems like it was supposed to be used by `reduceProjection` according to its documentation, but the constructor of `NamedType` disallows wildcards as prefixes so it didn't actually do anything there. Co-Authored-By: Dale Wijnand <[email protected]>
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Previously, derivedSelect would incorrectly approximate
fn.Rby? >: Nothing <: Anyini16997.min.scala, which subsequently lead to a kind-incorrect type applicationAny[Y]that broke type inference. #16999 proposed to fix this by changing type inference, but it seems like we don't need to do that if we make sure our wildcards are always kind-correct.Note that the wildcard logic in lookupRefined could be removed: it seems like it was supposed to be used by
reduceProjectionaccording to its documentation, but the constructor ofNamedTypedisallows wildcards as prefixes so it didn't actually do anything there.Co-Authored-By: Dale Wijnand [email protected]