Attempt to fix Scala 3 enum in snippet.sc, instead reproduce an issue with TypeRepr.of[A].memberType(subtype)

[MateuszKubuszok]

When Scala CLI snippet.sc is used macro generates assertion errors when Scala 3 enum is used:

• recommended way of calculating the type is TypeRepr.of[A].memberType(subtypeSymbol)

• the current way is based on subtypeSymbol.typeRef which cannot be used for types defined in

  class SomeClass {
    type InnerType
  }

  and enum and each case becomes a type defined in another class when we use snippet.sc (interestingly the issue does not appear for case objects nor case classes)

• however this recommended solution also upcasts parametherless casess, so that children of

   enum Foo:
     case Bar(value: Int)
     case Baz

  are resolved to List(Foo.Bar, Foo) (which breaks macro in another way).

Once this is solved, all Scala 3 snippets in documentation with enums - which required:

@main def example: Unit = {
// actual code
}

can have the workaround removed.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 89.53%. Comparing base (35f50d4) to head (7e16b56).
Report is 7 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #533      +/-   ##
==========================================
+ Coverage   87.72%   89.53%   +1.81%     
==========================================
  Files         136      104      -32     
  Lines        5440     2589    -2851     
  Branches      438      243     -195     
==========================================
- Hits         4772     2318    -2454     
+ Misses        668      271     -397     

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[MateuszKubuszok]

Recommended fix - unfortunately makes parameterless cases upcasted :(

[MateuszKubuszok]

Naive attempt to apply TypeRepr.of[A].memberType(subtype) fix once we already matched types. Does not work.

[MateuszKubuszok]

Same as above.

[MateuszKubuszok]

For some reason, when working with cases that this PR attempts to fix, I sometimes get StackOverflow from expr.asTerm.show(using Printer.TreeAnsiCode) :O

[MateuszKubuszok]

Poorly named test to check if fix worked without sbt publishLocal -> scala-cli scripts/test-snippets.scala trip.