[GROOVY-8978] NPE when accessing protected method from subclass clone

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.5.6
• Fix Version/s: 3.0.0-beta-1, 2.5.7
• Assignee: Paul King
• Reporter: paolo di tommaso
• Created: 04/Feb/19 14:21
• Updated: 20/May/19 07:31
• Resolved: 06/May/19 15:12

Description

I'm getting a NPE when running this snippet:

@groovy.transform.CompileStatic
class LazyMap implements Map<String,Object> {

    @Delegate protected Map<String,Object> target

    LazyMap() {
        target = new HashMap<>()
    }
}

@groovy.transform.CompileStatic
class TaskConfig extends LazyMap implements Cloneable {

    TaskConfig() {  }

    TaskConfig clone() {
        def copy = (TaskConfig)super.clone()
        copy.target = new HashMap<>(this.target)
        return copy
    }
}

The problem is that `this.target` in the clone method is evaluated to `null`. It works fine if the classes are not declared CompileStatic. It was also working fine with groovy version prior to 2.5.6.