// 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 Index {}

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 operator [](Index i) => null;
  void operator []=(Index i, B v) {}

  void test() {
    this /*@target=Test.[]=*/ [
        /*@typeArgs=Index**/ f()] = /*@typeArgs=B**/ f();

    this /*@target=Test.[]*/ /*@target=Test.[]=*/ [
            /*@typeArgs=Index**/ f()]
         ??= /*@typeArgs=B**/ f();

    this /*@target=Test.[]*/ /*@target=Test.[]=*/ [
            /*@typeArgs=Index**/ f()]
        /*@target=B.+*/ += /*@typeArgs=C**/ f();

    this /*@target=Test.[]*/ /*@target=Test.[]=*/ [
            /*@typeArgs=Index**/ f()]
        /*@target=B.**/ *= /*@typeArgs=B**/ f();

    this /*@target=Test.[]*/ /*@target=Test.[]=*/ [
            /*@typeArgs=Index**/ f()]
        /*@target=B.&*/ &= /*@typeArgs=A**/ f();

    /*@target=B.-*/ --this /*@target=Test.[]*/ /*@target=Test.[]=*/
        [/*@typeArgs=Index**/ f()];

    this /*@target=Test.[]*/ /*@target=Test.[]=*/
        [/*@typeArgs=Index**/ f()] /*@target=B.-*/ --;

    var /*@type=B**/ v1 = this /*@target=Test.[]=*/ [
        /*@typeArgs=Index**/ f()] = /*@typeArgs=B**/ f();

    var /*@type=B**/ v2 = this /*@target=Test.[]*/ /*@target=Test.[]=*/ [
            /*@typeArgs=Index**/ f()]
         ??= /*@typeArgs=B**/ f();

    var /*@type=A**/ v3 = this /*@target=Test.[]*/ /*@target=Test.[]=*/ [
            /*@typeArgs=Index**/ f()]
        /*@target=B.+*/ += /*@typeArgs=C**/ f();

    var /*@type=B**/ v4 = this /*@target=Test.[]*/ /*@target=Test.[]=*/ [
            /*@typeArgs=Index**/ f()]
        /*@target=B.**/ *= /*@typeArgs=B**/ f();

    var /*@type=C**/ v5 = this /*@target=Test.[]*/ /*@target=Test.[]=*/ [
            /*@typeArgs=Index**/ f()]
        /*@target=B.&*/ &= /*@typeArgs=A**/ f();

    var /*@type=B**/ v6 =
        /*@target=B.-*/ --this /*@target=Test.[]*/ /*@target=Test.[]=*/
            [/*@typeArgs=Index**/ f()];

    var /*@type=B**/ v7 = this /*@target=Test.[]*/ /*@target=Test.[]=*/
        [/*@typeArgs=Index**/ f()] /*@target=B.-*/ --;
  }
}

main() {}