JSTests/test262/test/language/expressions/assignment/dstr/array-empty-iter-close.js

// This file was procedurally generated from the following sources:
// - src/dstr-assignment/array-empty-iter-close.case
// - src/dstr-assignment/default/assignment-expr.template
/*---
description: Iterator is closed without iterating (AssignmentExpression)
esid: sec-variable-statement-runtime-semantics-evaluation
features: [Symbol.iterator, destructuring-binding]
flags: [generated]
info: |
    VariableDeclaration : BindingPattern Initializer

    1. Let rhs be the result of evaluating Initializer.
    2. Let rval be GetValue(rhs).
    3. ReturnIfAbrupt(rval).
    4. Return the result of performing BindingInitialization for
       BindingPattern passing rval and undefined as arguments.

    ArrayAssignmentPattern : [ ]

    1. Let iterator be GetIterator(value).
    2. ReturnIfAbrupt(iterator).
    3. Return IteratorClose(iterator, NormalCompletion(empty)).

    7.4.6 IteratorClose( iterator, completion )

    [...]
    6. Let innerResult be Call(return, iterator, « »).
    [...]

---*/
var nextCount = 0;
var returnCount = 0;
var thisValue = null;
var args = null;
var iterable = {};
var iterator = {
  next: function() {
    nextCount += 1;
    return { done: true };
  },
  return: function() {
    returnCount += 1;
    thisValue = this;
    args = arguments;
    return {};
  }
};
iterable[Symbol.iterator] = function() {
  return iterator;
};

var result;
var vals = iterable;

result = [] = vals;

assert.sameValue(nextCount, 0);
assert.sameValue(returnCount, 1);
assert.sameValue(thisValue, iterator, 'correct `this` value');
assert(!!args, 'arguments object provided');
assert.sameValue(args.length, 0, 'zero arguments specified');

assert.sameValue(result, vals);