// Copyright (c) 2017, the Dart project authors.  Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
// @dart=2.9
/*@testedFeatures=inference*/
library test;

class A {}

class B extends A {
  A operator +(C v) => null;
  B operator -(int i) => null;
  B operator *(B v) => null;
  C operator &(A v) => null;
}

class C extends B {}

T f<T>() => null;

class Test {
  B member;

  static void test(Test t) {
    /*@ type=Test* */  t
        ?. /*@target=Test.member*/ member = /*@ typeArgs=B* */ f();

     t?.
            /*@target=Test.member*/ /*@target=Test.member*/ member
         ??= /*@ typeArgs=B* */ f();

     t?.
            /*@target=Test.member*/ /*@target=Test.member*/ member
        /*@target=B.+*/ += /*@ typeArgs=C* */ f();

     t?.
            /*@target=Test.member*/ /*@target=Test.member*/ member
        /*@target=B.**/ *= /*@ typeArgs=B* */ f();

     t?.
            /*@target=Test.member*/ /*@target=Test.member*/ member
        /*@target=B.&*/ &= /*@ typeArgs=A* */ f();

    /*@target=B.-*/ --  t?.
        /*@target=Test.member*/ /*@target=Test.member*/ member;

     t?.
            /*@target=Test.member*/ /*@target=Test.member*/ member
        /*@target=B.-*/ --;

    var /*@ type=B* */ v1 =
        /*@ type=Test* */  t
            ?. /*@target=Test.member*/ member = /*@ typeArgs=B* */ f();

    var /*@ type=B* */ v2 =
         t
                ?. /*@target=Test.member*/ /*@target=Test.member*/ member
             ??= /*@ typeArgs=B* */ f();

    var /*@ type=A* */ v3 =
         t
                ?. /*@target=Test.member*/ /*@target=Test.member*/ member
            /*@target=B.+*/ += /*@ typeArgs=C* */ f();

    var /*@ type=B* */ v4 =
         t
                ?. /*@target=Test.member*/ /*@target=Test.member*/ member
            /*@target=B.**/ *= /*@ typeArgs=B* */ f();

    var /*@ type=C* */ v5 =
         t
                ?. /*@target=Test.member*/ /*@target=Test.member*/ member
            /*@target=B.&*/ &= /*@ typeArgs=A* */ f();

    var /*@ type=B* */ v6 = /*@target=B.-*/ --  t
        ?. /*@target=Test.member*/ /*@target=Test.member*/ member;

    var /*@ type=B* */ v7 =  t
            ?. /*@target=Test.member*/ /*@target=Test.member*/ member
        /*@target=B.-*/ --;
  }
}

main() {}