Implement SIP-77: Method Block End Markers

[soronpo]

Implements scala/improvement-proposals#116

[soronpo]

Are the tests in the main branch supposed to be working correctly? These changes were fine locally for 3.7.4, but I can't get the main branch to test successfully even without any modifications.

[hamzaremmal]

@soronpo I haven't checked why this PR doesn't pass in details as I'm on my phone, but from the diff, I would say that you need to add the object in scala.Predef, not just stdlibPatches.
And to answer your question, of course the tests are supposed to work correctly :).

[bishabosha]

[error] Test dotty.tools.pc.tests.completion.CompletionBacktickSuite.soft-keyword-ident failed: java.lang.AssertionError:
[error] expected single completion item, obtained 2 items.
[error] List(end: Int
[error] , endMarkersForMethodBlocks - scala.runtime.stdLibPatches.language.experimental
[error] )
[error] , took 0.234 sec
[info] Test run dotty.tools.pc.tests.completion.Co

@soronpo looks like your new definition adds a new completion in this test

[soronpo]

[error] Test dotty.tools.pc.tests.completion.CompletionBacktickSuite.soft-keyword-ident failed: java.lang.AssertionError:
[error] expected single completion item, obtained 2 items.
[error] List(end: Int
[error] , endMarkersForMethodBlocks - scala.runtime.stdLibPatches.language.experimental
[error] )
[error] , took 0.234 sec
[info] Test run dotty.tools.pc.tests.completion.Co

@soronpo looks like your new definition adds a new completion in this test

Blame the AI, hahaha. I'll check it out, thanks.

[soronpo]

It's implemented and the CI should pass now, but currently there is a workaround for the completion tests to prevent suggesting experimental language values. Should the expected completion result change or indeed rejecting the suggestion is the right approach? If so, what is the proper way to implement it?

[som-snytt]

Thanks, I just noticed #16062 where I did not have the wherewithal to SIP it.

[som-snytt]

For infix, the trees are InfixOp at parser, as at https://github.com/scala/scala3/pull/16062/files

I didn't see a test for it, but my motivating example was infix for some reason.

Just to double-check

      InfixOp(Ident(sb), Ident(++=), Literal("hello")),
      InfixOp(Ident(sb), Ident(++=), Literal("world"))))

becomes

      Apply(Select(Select(This(Ident(C)), sb), ++=), List(Literal("hello"))),
      Apply(Select(Select(This(Ident(C)), sb), ++=), List(Literal("world")))))