[GROOVY-10897] Static Type Checking selects wrong method for abstract method call check

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 4.0.7
• Fix Version/s: 4.0.8, 3.0.20
• Component/s: Static Type Checker
• Assignee: Eric Milles
• Reporter: Hannes Greule
• Created: 05/Jan/23 21:02
• Updated: 08/Dec/23 21:07
• Resolved: 16/Jan/23 18:28

Description

Consider following code:

@CompileStatic
class E extends BImpl {
    @Override
    void a() {
        super.a();
    }
    static void main(args) { }
}
interface A {
    void a()
}
interface B extends A {
    @Override
    void a()
}
class AImpl implements A {
    @Override
    void a() {
    }
}
class BImpl extends AImpl implements B {
} 

Compiling it will fail with the error
[Static type checking] - Abstract method a() cannot be called directly

However, when running it without @CompileStatic or when writing similar code in Java, it will select the non-abstract method from AImpl instead.

It seems like this is a problem in the code to choose the best method here: https://github.com/apache/groovy/blob/ea6ba7c6fcfefe3d8abdfbb6e20a44b1ebb8823e/src/main/java/org/codehaus/groovy/transform/stc/StaticTypeCheckingSupport.java#L1091

The distance from BImpl to B to the interface is less than (1) the distance to AImpl (4), therefore the abstract method is chosen as best method.

This originally happened when extending AbstractSet and calling super.addAll(...).

Issue Links

• relates to: GROOVY-11242 Stackoverflow error when calling super from overridden method