Ensure the inline match scrutinee type conforms to the recalculated type #24988
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When simplifying an inline match, the compiler intentionally recalculates the type of the scrutinee by removing Typed nodes. However, after that recalculation, it uses that type to define a scrutinee proxy symbol, which would cause typing errors, when it would try to point to the original tree eg: it would generate: ``` val b: B // B <: A val scrutinee$: B // type recalculated from (b: A) = (b: A) // original tree; after this fix we add .asInstanceOf[B] ``` The reason this issue has been unnoticed before is because for the proxy symbol to appear, the scrutinee has to be used on the right hand side (directly or through a unapply pattern) which the original tests didn't have.
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When simplifying an inline match, the compiler intentionally recalculates the type of the scrutinee by removing
Typednodes. However, after that recalculation, it uses that type to define a scrutinee proxy symbol, which would cause typing errors, when it would try to point to the original tree eg:it would generate:
The reason this issue has been unnoticed before is because for the proxy symbol to appear, the scrutinee has to be used on the right hand side (directly or through an unapply pattern) which the original tests didn't have.
Fixes #24479
Some additional context: #11291