scala-cli eagerly sets -java-output-version not understood by scalac

[som-snytt]

Version(s)
Scala CLI version: 1.0.0-RC2
Scala version (default): 3.2.2

Describe the bug
Today I was resolved to try scala-cli again, so I zapped my caches, followed the getting started on scala-lang, googled for scala-cli docs because I saw an announcement recently about the latest version, kind of finally found the virtuslab blog, though not the recent announcement I thought I remembered.

This is to say, I was surprised there was still more than one step to start using scala-cli, which I will use often because the FOMO was killing me.

Trying the trivial pwd example requires tweaks, but the hard part is having to downgrade my ambient JDK or install via --jvm 19.

To Reproduce

➜  snips scala-cli pwd.sc
Compiling project (Scala 3.2.2, JVM)
Error: 20 is not a valid choice for -java-output-version
  scalac -help  gives more information
Error compiling project (Scala 3.2.2, JVM)
Compilation failed

It still fails if I add

//> using option -java-output-version:19

Expected behaviour
It would be nicer not to specify the compiler option, which ought to default to what is natural.

Unfortunately, scalac doesn't report its default:

 -java-output-version  Compile code with classes specific to the given version of the Java platform available on the
                       classpath and emit bytecode for this version. Corresponds to -release flag in javac.
                       Choices 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19

Scala 2 does the obvious and uses the obvious option name:

  -release:<release>           Compile for a version of the Java API and target class file. (8,9,10,11,12,13,14,15,16,17,18,19,[20])

[som-snytt]

I encountered this again today while evangelizing at scala/scala3#18107

[lwronski]

Hi @som-snytt, thanks for reporting. Scala CLI uses the -release option, which is now aliased to -java-output-version for backward compatibility with older Scala versions.

Setting -release 19 should solve the issue, allowing you to override the default value:

//> using option -release 19

I think that if users pass //> using option -java-output-version:19, scala-cli should override the default for --release options.