JSTests/test262/test/language/statements/class/elements/privatefieldget-typeerror-4.js

// Copyright (C) 2017 Valerie Young. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.

/*---
description: TypeError when referenced private field cannot be found in `this`'s [[PrivateFieldValues]]
esid: sec-getvalue
info: |
  GetValue ( V )
    ...
    5. If IsPropertyReference(V), then
      ...
      b. If IsPrivateReference(V), then
        i. Let env be the running execution context's PrivateNameEnvironment.
        ii. Let field be ? ResolveBinding(GetReferencedName(V), env).
        iii. Assert: field is a Private Name.
        iv. Return ? PrivateFieldGet(field, base).

  PrivateFieldGet (P, O )
    1. Assert: P is a Private Name value.
    2. If O is not an object, throw a TypeError exception.
    3. Let entry be PrivateFieldFind(P, O).
    4. If entry is empty, throw a TypeError exception.

  PrivateFieldFind (P, O)
    1. Assert: P is a Private Name value.
    2. Assert: O is an object with a [[PrivateFieldValues]] internal slot.
    3. For each element entry in O.[[PrivateFieldValues]],
      a. If entry.[[PrivateName]] is P, return entry.
    4. Return empty.

features: [class, class-fields-private]
---*/

function classfactory() {
  return class {
    #x;
    f() {
      this.#x;
    }
  }
}

var C1 = classfactory();
var C2 = classfactory();

var c1 = new C1();
var c2 = new C2();

assert.throws(TypeError, function() {
  // when f() is called in class C1, the Private Name binding for #x in C1 will
  // not found in C2's [[PrivateNameValues]]
  c1.f.call(c2);
})