[GROOVY-10220] Unexpected type mismatch when having conflicting type parameter names

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 4.0.0-beta-2
• Component/s: Static Type Checker
• Assignee: Eric Milles
• Reporter: Thodoris Sotiropoulos
• Created: 10/Sep/21 12:09
• Updated: 03/Feb/22 22:32
• Resolved: 21/Sep/21 20:52

Description

I have the following Groovy program

 

class A<X, T extends Number> {}
class B<T> {
  A<? extends T, Number> x;
  B(A<? extends T, Number> x) {
    this.x = x;
  }
}

Actual Behaviour

 

org.codehaus.groovy.control.MultipleCompilationErrorsException: startup failed:
test.groovy: 5: [Static type checking] - Incompatible generic argument types. Cannot assign A<java.lang.Object, java.lang.Number> to: A<? extends T, java.lang.Number>
 @ line 5, column 14.
       this.x = x;
                ^1 error

Expected Behaviour

Compile successfully

 

Tested against master