Fix #9439: Translate Java varargs ...T into T* instead of (T & Object)*
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...T into T* instead of (T & Object)*...T into T* instead of (T & Object)*
sjrd
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In bytecode, vararg parameters are encoded as arrays with the ACC_VARARGS flag set on the method. Previously we first parsed them as arrays then translated the array into a repeated param. With this commit we directly parse them as repeated params. This isn't really any simpler since we need to keep track of the fact that we're in a varargs method, but it will become useful in the next commit where we start treating arrays differently from varargs (`T[]` will still be translated as `Array[T & Object]` whereas `T...` will be translated as `T*` and handled specially in ElimRepeated to preserve soundness). Similarly for joint compilation, we now directly desugar varargs as `RepeatedParam[T]` instead of `Array[T] @Repeated`, this doesn't change anything currently because: - When giving a type to the method, we call `annotatedToRepeated` on each parameter type - `typedAppliedTypeTree` takes care of adding `& Object` for both `Array[T]` and `RepeatedParam[T]` coming From Java (this is what the next commit will change).
This is much more convenient for users but is more complicated for the compiler since we might still need to translate the varargs into an `Object[]` in bytecode. Since ElimRepeated was already responsible for doing some adaptation of repeated arguments, it now also takes care of this (unlike Scala 2 where this is handled in Erasure). Fixes scala#9439.
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This is much more convenient for users but is more complicated for the
compiler since we still need to translate the varargs into an
Object[]in bytecode. Since ElimRepeated was already responsible for doing some
adaptation of repeated arguments, it now also takes care of this (this
differs from Scala 2 which handles this at Erasure).