Switch to Truffle PE mode before calling into Enso

[JaroslavTulach]

Pull Request Description

Enter partial evaluation mode via CallTarget.call before invoking InteropLibrary. Fixes #5782.

Checklist

Please include the following checklist in your PR:

• All code conforms to the
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• All code has been tested:
  • Existing Unit tests must continue to pass

[hubertp]

gotta love Java :)

[radeusgd]

Why do we need this method instead of putting throw ex directly at callsite?

[radeusgd]

Okay, I see that for example ArityException or UnsupportedTypeException extend InteropException which apparently does not seem to inherit RuntimeException.

So I guess this is the reason for this magic?

But that seems totally unsafe - since we do an unchecked cast to RuntimeException of something that we know that it doesn't extend RuntimeException.

If the cast is unchecked, I guess it will go through, but it will violate the typesystem rules. That sounds very worrying at first sight.

Can we get a comment (in the code, as part of this function's doc comment) explaining why we are doing it and why is it safe in this context? (If it is safe...)

[JaroslavTulach]

This is a standard way to propagate checked exception thru Java language. Java language has (too) strict rules about checked exceptions, but there is nothing like that in the JVM (as demonstrated by Scala ignoring checked exceptions altogether). Sometimes it is useful to propagate checked exception even the Java method signatures are against it. This is the case. We have to tunnel the exception thru CallTarget interface now. Rather than wrapping the exception into runtime and unpacking it, I am trying to throw it directly. Btw. this is not the first place where this coding technique is used. There are other raise methods around the codebase already.