[GROOVY-10816] @NamedVariant does not work on methods on a trait or default methods on an interface

• Type: Bug
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Affects Version/s: 4.0.6
• Labels: default-methods named-parameters
• Assignee: Unassigned
• Reporter: Robert Elliot
• Created: 07/Nov/22 22:42
• Updated: 24/Aug/23 12:16

Description

The following code fails to compile:

import groovy.transform.NamedVariant

trait Foo {
  @NamedVariant
  def foo(String username = "sdf", String email = "ghj") {}
}

with this error:

Groovyc: Error during @NamedVariant processing. Class Foo$Trait$Helper already has a named-arg method of type [org.codehaus.groovy.ast.Parameter@15247533[name: namedArgs, type: java.util.Map, hasDefaultValue: false]]

It works fine as a class.

It fails as an interface with a default method.

Perhaps this is intended, but if so I failed to find any documentation specifying that @NamedVariant only works with classes.