tests/compiler/dart2js_native/native_field_name_test.dart

// Copyright (c) 2011, 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.

import 'native_testing.dart';

// Check that native fields are not incorrectly renamed.

@Native("A")
class A {
  int myLongPropertyName;
  int getValue;

  int method(int z) => myLongPropertyName;
}

// This code is inside the setup function, so the function names are not
// accessible, but the makeA variable is global through the magic of JS scoping.
// The contents of this are of course not analyzable by the compiler.
void setup() {
  JS('', r"""
(function(){
  function getter() {
    return ++this.getValue;
  }

  function setter(x) {
    this.getValue += 10;
  }

  function A(){
    var a = Object.create(
        { constructor: A },
        { myLongPropertyName: { get: getter,
                                set: setter,
                                configurable: false,
                                writeable: false
                              }
        });
    a.getValue = 0;
    return a;
  }

  makeA = function(){return new A()};

  self.nativeConstructor(A);
})()""");
}

/*A*/ makeA() native;

main() {
  nativeTesting();
  setup();
  var a = makeA();
  a.myLongPropertyName = 21;
  int gotten = a.myLongPropertyName;
  Expect.equals(11, gotten);

  var a2 = makeA();
  if (a2 is A) {
    // Inside this 'if' the compiler knows that a2 is an A, so it is tempted
    // to access myLongPropertyName directly, using its minified name.  But
    // renaming of native properties can only work using getters and setters
    // that access the original name.
    a2.myLongPropertyName = 21;
    int gotten = a2.myLongPropertyName;
    Expect.equals(11, gotten);
  }
}