[GROOVY-10624] Nested diamond operators do not work correctly although the expected type argument is known

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 3.0.11, 4.0.3
• Component/s: Static Type Checker
• Assignee: Eric Milles
• Reporter: Thodoris Sotiropoulos
• Created: 13/May/22 14:12
• Updated: 24/Jul/22 12:16
• Resolved: 17/May/22 18:58

Description

I have the following program:

class C<T> {
  C(D<T> x) {}
}

class D<T> {}


class Test {
  void test() {
    C<Float> x = new C<>(new D<>()); // type variables are instantiated with type Float because of the left-hand side.
  }

}

Actual behavior

org.codehaus.groovy.control.MultipleCompilationErrorsException: startup failed:
test.groovy: 10: [Static type checking] - Incompatible generic argument types. Cannot assign C<java.lang.Object> to: C<java.lang.Float>
 @ line 10, column 18.
       C<Float> x = new C<>(new D<>());
                    ^

1 error

Expected behavior

Compile successfully

Tested against master (commit: ee12bb52381e8f0583c61fc25d43de1f55b80a87)