Third try for a fix for #1044: handle TypevarsMissContext mode in wildApprox #1064
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When `wildApprox` encounters a PolyParam it approximates it by its bounds in the current constraint set, but this is incorrect if `TypevarsMissContext` is set, we might get the bounds of another use of this `PolyType`. This is exactly what happened in i1044.scala where the implicit view `refArrayOps` needs to be used twice with two different type parameters. The fix is to approximate a PolyParam by its original bounds in its PolyType if `TypevarsMissContext` is set. This fix was inspired by the approach of scala#1054.
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Third try for a fix for #1044: handle TypevarsMissContext mode in wildApprox
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Review by @odersky, this is an alternative to #1054
When
wildApproxencounters a PolyParam it approximates it by itsbounds in the current constraint set, but this is incorrect if
TypevarsMissContextis set, we might get the bounds of another use ofthis
PolyType. This is exactly what happened in i1044.scala where theimplicit view
refArrayOpsneeds to be used twice with two differenttype parameters.
The fix is to approximate a PolyParam by its original bounds in its
PolyType if
TypevarsMissContextis set.This fix was inspired by the approach of #1054.