Improve support for Scala 3 code generation through Scalameta dialects #63
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Also remove the hack to uppercase enums in #62, as that's not needed anymore. Quasiquotes need the dialect to be fixed at compile time via import. As it runs during compile time, we can't parameterize it with a dialect. This is something we can't do here, as we want to dynamically toggle the output variant, depending on the scala version of the project using the plugin. So to help keeping changes in check, we keep Scala 2 syntax in our quasiquote literals, i.e. we parse q"import io.circe._"), and only apply the dialect during pretty printing, which works for most things where the AST is the same. I.e., imports have the same AST representation.
…12 for this module
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Not sure where this ghost build job is coming from: |
It's the other way around fortunately. We introduced the uppercasing in #63 which isn't part of any release, but would have impacted code with heavy use of enums. I'm reverting that here to reduce the potential impact. |
thanks for the context - makes sense now 🙇 |
This also reverts the hack to use uppercase enums from #62, as it's not needed anymore.
Reasoning for using dialects only during printing
Scalameta uses dialects to express differentes between Scala versions. Quasiquotes need the dialect to be fixed at compile time via import. As it runs during compile time, we can't parameterize it with a dialect dynamically. This is something we can't do here, as we want to dynamically toggle the output variant, depending on the Scala version of the project using the plugin.
On the other hand, we have a lot of code gen blocks using quasiquotes. We also have tons of Scala 2 syntax in our tests.
So to help keeping changes in check, we keep Scala 2 syntax in our quasiquote literals and in tests for now, i.e. we parse
q"import io.circe._"), and only apply the dialect during pretty printing. This works fine for most things where the AST is the same. I.e. imports have the same AST representation in Scala 2 and 3, even though the syntax is different.