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// Copyright (C) 2016 the V8 project authors. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-globaldeclarationinstantiation
es6id: 15.1.8
description: Declaration of lexical bindings
info: |
[...]
16. For each element d in lexDeclarations do
a. NOTE Lexically declared names are only instantiated here but not
initialized.
b. For each element dn of the BoundNames of d do
i. If IsConstantDeclaration of d is true, then
1. Perform ? envRec.CreateImmutableBinding(dn, true).
ii. Else,
1. Perform ? envRec.CreateMutableBinding(dn, false).
[...]
---*/
// Extensibility of the global object should have no bearing on lexical
// declarations.
Object.preventExtensions(this);
$.evalScript('let test262let = 1;');
test262let = 2;
assert.sameValue(test262let, 2, '`let` binding is mutable');
assert.sameValue(
this.hasOwnProperty('test262let'),
false,
'property not created on the global object (let)'
);
$.evalScript('const test262const = 3;');
assert.throws(TypeError, function() {
test262const = 4;
}, '`const` binding is strictly immutable');
assert.sameValue(test262const, 3, '`const` binding cannot be modified');
assert.sameValue(
this.hasOwnProperty('test262const'),
false,
'property not created on the global object (const)'
);
$.evalScript('class test262class {}');
test262class = 5;
assert.sameValue(test262class, 5, '`class` binding is mutable');
assert.sameValue(
this.hasOwnProperty('test262class'),
false,
'property not created on the global object (class)'
);
|
