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Diffstat (limited to 'tests/untried/pos/t8177b.scala')
-rw-r--r-- | tests/untried/pos/t8177b.scala | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/tests/untried/pos/t8177b.scala b/tests/untried/pos/t8177b.scala new file mode 100644 index 000000000..82f41b615 --- /dev/null +++ b/tests/untried/pos/t8177b.scala @@ -0,0 +1,13 @@ +// exercise coevolveSym: SingleType with an underlying RefinedType, via a type alias +trait Thing { type A } +object IntThing extends Thing { type A = Int } +object ThingHolder { type Alias[AIn] = Thing { type A = AIn } } + +// The following erroneously failed with error: method f overrides nothing. +// because asSeenFrom produced a typeref of the shape T'#A where A referred to a symbol defined in a T of times past +// More precisely, the TypeRef case of TypeMap's mapOver correctly modified prefix +// from having an underlying type of { type A = Ain } to { type A = Int }, with a new symbol for A (now with info Int), +// but the symbol in the outer type ref wasn't co-evolved (so it still referred to the { type A = AIn } underlying the old prefix) +// coEvolveSym used to only look at prefixes that were directly RefinedTypes, but they could also be SingleTypes with an underlying RefinedType +class View[AIn](val in: ThingHolder.Alias[AIn]) { def f(p: in.A): in.A = p } +class SubView extends View[Int](IntThing) { override def f(p: in.A): in.A = p } |