[GROOVY-8856] Trait with generic will fail compilation if it has a static method that return the defined generic type.

• Type: Bug
• Status: Closed
• Priority: Blocker
• Resolution: Not A Problem
• Affects Version/s: 2.5.0, 2.5.1, 2.5.2, 2.5.3
• Component/s: Compiler
• Environment: macOS 10.14 ; OpenJDK 1.8.0_181-b02
• Assignee: Unassigned
• Reporter: Dwi Elfianto
• Created: 24/Oct/18 12:19
• Updated: 27/Oct/18 01:39
• Resolved: 27/Oct/18 01:39

Description

If you define a trait with generic type T and have a static method that return that type, compilation will fail with the following message:

Error:(5, 5) Groovyc: unable to resolve class T

Simple code for reproducing this bug:

trait MyTrait<T extends List> {
    static T myMethod() {
        return [1, 2, 3]
    }
}

 Groovy 2.4.x does not have this issue, from my testing this only happen in 2.5.x