Meta-annotations written at use-site are ignored

Compiler version

3.0.0

Minimized code

This is an issue I’ve encountered while trying to port squeryl to scala 3.

In a MyColumnBase.java file:

import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;

@Retention(RetentionPolicy.RUNTIME)
public @interface MyColumnBase {

    String value() default "";
    
    String name() default "";

}

and in a scala file:

import annotation.meta.field

type MyColumn = MyColumnBase @field

class MyTable(
  @MyColumn(name="BRAND_NAME")
  val brandName: String
) {
    @MyColumn(name="WEIGHT")
    val weightInGrams: Option[String] = None
}

val clasz = classOf[MyTable]

for(m <- clasz.getDeclaredFields) {
  m.setAccessible(true)
  if(m.getName == "weightInGrams" || m.getName == "brandName"){
    println(s"inspecting field ${m.getName}")
    assert(m.getAnnotations().size == 1, s"no annotation found for ${m.getName}")
  }
}

Output

Array() had size 0 instead of expected size 1 no annotation found for brandName

Expectation

I would expect to see the annotation on the field brandName. In scala 2.13, I can at least.

[smarter]

Same thing yes.

[smarter]

In that case the meta-annotation isn’t needed since we’re directly annotating a field (from https://www.scala-lang.org/api/current/scala/annotation/meta/index.html):

By default, annotations on (val-, var- or plain) constructor parameters end up on the parameter, not on any other entity. Annotations on fields by default only end up on the field.