tor-browser

The Tor Browser
git clone https://git.dasho.dev/tor-browser.git
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unscopables-prop-get-err.js (1152B)

      1 // Copyright 2015 Mike Pennisi. All rights reserved.
      2 // This code is governed by the BSD license found in the LICENSE file.
      3 
      4 /*---
      5 esid: sec-getidentifierreference
      6 es6id: 8.1.2.1
      7 description: >
      8  Behavior when accessing property of `Symbol.unscopables` property throws an
      9  error
     10 info: |
     11  [...]
     12  2. Let envRec be lex's EnvironmentRecord.
     13  3. Let exists be ? envRec.HasBinding(name).
     14 
     15  8.1.1.2.1 HasBinding
     16 
     17  [...]
     18  5. If the withEnvironment flag of envRec is false, return true.
     19  6. Let unscopables be ? Get(bindings, @@unscopables).
     20  7. If Type(unscopables) is Object, then
     21     a. Let blocked be ToBoolean(? Get(unscopables, N)).
     22     b. If blocked is true, return false.
     23 
     24  13.11.7 (The `with` Statement) Runtime Semantics: Evaluation
     25 
     26  [...]
     27  5. Set the withEnvironment flag of newEnv’s EnvironmentRecord to true.
     28  [...]
     29 flags: [noStrict]
     30 features: [Symbol.unscopables]
     31 ---*/
     32 
     33 var env = { x: 86 };
     34 env[Symbol.unscopables] = {};
     35 
     36 Object.defineProperty(env[Symbol.unscopables], 'x', {
     37  get: function() {
     38    throw new Test262Error();
     39  }
     40 });
     41 
     42 with (env) {
     43  assert.throws(Test262Error, function() {
     44    x;
     45  });
     46 }
     47 
     48 reportCompare(0, 0);