[GROOVY-7789] ClosureParams type inference compilation error when wrapping closure with object

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.4.6, 2.5.15, 4.0.0-beta-1, 3.0.9
• Fix Version/s: 3.0.14, 2.5.20, 4.0.7
• Component/s: Static compilation
• Assignee: Eric Milles
• Reporter: Krzysztof Białek
• Created: 14/Mar/16 20:45
• Updated: 19/Sep/23 14:41
• Resolved: 05/Nov/22 19:36

Description

The following code does not compile:

import groovy.transform.*
import groovy.transform.stc.*

@CompileStatic
class Test {

    class A<IN> {
        Closure c

        A(@ClosureParams(value = FromString, options = 'IN') Closure c) {
            this.c = c
        }

        void call(IN param) {
            c.call(param)
        }
    }

    def <IN> A wrap(@ClosureParams(value = FromString, options = 'IN') Closure c) {
        new A<IN>(c)
    }

    def test() {
        (wrap { i -> i.size() }).call([])
    }

}

Compilation error:

org.codehaus.groovy.control.MultipleCompilationErrorsException: startup failed:
/tmp/groovy-2.4.6/test.groovy: 25: [Static type checking] - Cannot find matching method java.lang.Object#size(). Please check if the declared type is right and if the method exists.
 @ line 24, column 22.
           (wrap { i -> i.size() }).call([])

I'd expect 'i' being infered as java.util.List
Explicit this.<List>wrap does not help neither

Issue Links

• relates to: GROOVY-11168 Ability to `@DelegatesTo` the return type