Enable exhaustivity and reachability checks for opaque types #23909
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| classSym.is(Case) || | ||
| (tpw.isInstanceOf[TypeRef] && { | ||
| val tref = tpw.asInstanceOf[TypeRef] | ||
| tref.symbol.isOpaqueAlias && !tref.info.hiBound.isNothingType |
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Should I extract this logic into a separate function? If so, where would be a good place to put it?
| else NoType | ||
| }.filter(_.exists) | ||
| parts | ||
| case tref: TypeRef if tref.symbol.isOpaqueAlias && !tref.info.hiBound.isNothingType => |
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None of this logic should be limited to opaque type aliases. It should work also for abstract type members, or not work for either. From the outside of its scope, an opaque type alias is an abstract type member. It makes no sense to treat them differently in this situation.
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c70aaa3
Is this correct?
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Seems correct to me, as far as that comment is concerned.
I cannot vouch for the whole PR. I am not familiar with pattern-match analysis.
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I see, thank you for the review.
closes #23620
If opaques type have upper bounds, use it for exhaustivity and reachability checks