JSTests/test262/test/language/global-code/script-decl-func.js

// 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 function where permissible
info: |
  [...]
  9. Let declaredFunctionNames be a new empty List.
  10. For each d in varDeclarations, in reverse list order do
      a. If d is neither a VariableDeclaration or a ForBinding, then
         i. Assert: d is either a FunctionDeclaration or a
            GeneratorDeclaration.
         ii. NOTE If there are multiple FunctionDeclarations for the same name,
             the last declaration is used.
         iii. Let fn be the sole element of the BoundNames of d.
         iv. If fn is not an element of declaredFunctionNames, then
             1. Let fnDefinable be ? envRec.CanDeclareGlobalFunction(fn).
             2. If fnDefinable is false, throw a TypeError exception.
             3. Append fn to declaredFunctionNames.
             4. Insert d as the first element of functionsToInitialize.
  [...]
  17. For each production f in functionsToInitialize, do
      a. Let fn be the sole element of the BoundNames of f.
      b. Let fo be the result of performing InstantiateFunctionObject for f
         with argument env.
      c. Perform ? envRec.CreateGlobalFunctionBinding(fn, fo, false).
  [...]

  8.1.1.4.16 CanDeclareGlobalFunction

  1. Let envRec be the global Environment Record for which the method was
     invoked.
  2. Let ObjRec be envRec.[[ObjectRecord]].
  3. Let globalObject be the binding object for ObjRec.
  4. Let existingProp be ? globalObject.[[GetOwnProperty]](N).
  5. If existingProp is undefined, return ? IsExtensible(globalObject).
includes: [propertyHelper.js]
---*/

$262.evalScript('function brandNew() {}');

assert.sameValue(
  typeof brandNew, 'function', 'new binding on an extensible global object'
);
verifyEnumerable(this, 'brandNew');
verifyWritable(this, 'brandNew');
verifyNotConfigurable(this, 'brandNew');

Object.defineProperty(this, 'configurable', { configurable: true, value: 0 });
Object.defineProperty(
  this,
  'nonConfigurable',
  { configurable: false, writable: true, enumerable: true, value: 0 }
);

// Prevent extensions on the global object to ensure that detail is not
// considered by any of the declarations which follow.
Object.preventExtensions(this);

$262.evalScript('function configurable() {}');

assert.sameValue(
  typeof configurable, 'function', 'like-named configurable property'
);
verifyEnumerable(this, 'configurable')
verifyWritable(this, 'configurable');
verifyNotConfigurable(this, 'configurable');

$262.evalScript('function nonConfigurable() {}');

assert.sameValue(
  typeof nonConfigurable,
  'function',
  'like-named non-configurable data property that is writable and enumerable'
);
verifyEnumerable(this, 'nonConfigurable');
verifyWritable(this, 'nonConfigurable');
verifyNotConfigurable(this, 'nonConfigurable');