Support 2-blank-line-termination in REPL in Scala 3

[cruiztorresj]

Hello, I was trying to terminate a statement pressing enter twice but it only works for Scala 2, can you please make it available for Scala 3 over Java 17 too?

Here's a screenshot depicting the issue both with SBT and the Scala 3 standalone application.

And here's a successful execution within Scala 2.

Java Virtual Machine Information:
java 17.0.3.1 2022-04-22 LTS
Java(TM) SE Runtime Environment (build 17.0.3.1+2-LTS-6)
Java HotSpot(TM) 64-Bit Server VM (build 17.0.3.1+2-LTS-6, mixed mode, sharing)

Thanks!

--
Caleb.

[som-snytt]

I think this was deemed unnecessary because of magic JLine editing capabilities, but I can't find the ticket or conversation. I also thought ctl-c was supported, but for me it exits the REPL.

[cruiztorresj]

Thanks for getting back with an answer.
I am not sure why it was deemed that way, IMO it is a Scala's REPL core functionality. It's even promoted in some books, e.g. THE Scala book by Martin Odersky et all.
Have a good day!

--
Caleb

[bishabosha]

If I could guess why this occurs it would be to support optional braces syntax - however to see 7 blank lines before any code is a bit absurd :)

Edit: I mean absurd for REPL to accept 7 blank lines as intentional code

[cruiztorresj]

Not absurd at all, those seven blank lines were meant to showcase enter was hit n (Seven in this case) number of times without the REPL terminating the statement as intended.
Thanks for changing this issue title, yours is more adequate.

Well, good luck buds. 🚀

[SethTisue]

Scala 2 lost this behavior around the time the JLine 3 upgrade landed (scala/bug#12266), but Dale and I restored it in scala/scala#9407

as discussed at 12266, control-G also works for noping out (including in Scala 3), so that's a workaround for now though as I wrote there:

tends to leave junk on the screen, but perhaps that's JLine's fault rather than something in the Scala integration