Wrap multiple values in switch expression case

[fawind]

Closes #540

• Wrap multiple values covered in a switch expression case if they exceed the max line length.

  switch (e) {
  -  case SOME_RATHER_LONG_NAME_1, SOME_RATHER_LONG_NAME_2, SOME_RATHER_LONG_NAME_3 -> {}
  +  case SOME_RATHER_LONG_NAME_1,
  +    SOME_RATHER_LONG_NAME_2,
  +    SOME_RATHER_LONG_NAME_3 -> {}
  }

• Also collapse empty case blocks in switch expressions.

   switch (e) {
  -  case CASE_A -> {
  -  }
  +  case CASE_A -> {}
   }

[abrudin]

Was it ever clear why this PR failed the Java 16 check? The logs have expired, is it possible to retrigger the checks for this PR?

[fawind]

The failing JDK 16 and now 17 check seems to be unrelated to this change. I believe it's a general problem with the formatter as e.g. the same tests fail on master for the JDK 17 check (ref). I don't think it's in the scope of this PR to fix them.

@cushon, mind taking a look when you have a spare minute? Thanks!

[cushon]

Thanks for the fix!

I don't think it's in the scope of this PR to fix them.

Agreed: the tests aren't passing on JDK 17 at head yet. That configuration is marked as 'experimental' and won't block merging, but the UI makes it look like a failure.

Also I realized we're not breaking after the -> in expression switches with expression bodies either, but that doesn't need to happen in this change:

return switch (e) {
  case SOME_RATHER_LONG_NAME_1,
      SOME_RATHER_LONG_NAME_2,
      SOME_RATHER_LONG_NAME_3,
      SOME_RATHER_LONG_NAME_4,
      SOME_RATHER_LONG_NAME_5,
      SOME_RATHER_LONG_NAME_6,
      SOME_RATHER_LONG_NAME_7 ->
      fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff();
  case SOME_RATHER_LONG_NAME_8 ->
      fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff();
};