pkg/front_end/testcases/inference_new/infer_assign_to_property_null_aware.dart

// 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() {}