src/spread/mult-iter.case

// Copyright (C) 2016 the V8 project authors. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
desc: Spread operator following other arguments with a valid iterator
template: default
features: [Symbol.iterator]
info: |
    12.3.6.1 Runtime Semantics: ArgumentListEvaluation

    ArgumentList : ... AssignmentExpression

    1. Let list be an empty List.
    2. Let spreadRef be the result of evaluating AssignmentExpression.
    3. Let spreadObj be GetValue(spreadRef).
    4. Let iterator be GetIterator(spreadObj).
    5. ReturnIfAbrupt(iterator).
    6. Repeat
       a. Let next be IteratorStep(iterator).
       b. ReturnIfAbrupt(next).
       c. If next is false, return list.
       d. Let nextArg be IteratorValue(next).
       e. ReturnIfAbrupt(nextArg).
       f. Append nextArg as the last element of list.
---*/

//- setup
var iter = {};
iter[Symbol.iterator] = function() {
  var nextCount = 3;
  return {
    next: function() {
      nextCount += 1;
      return { done: nextCount === 6, value: nextCount };
    }
  };
};
//- args
1, 2, 3, ...iter
//- body
assert.sameValue(arguments.length, 5);
assert.sameValue(arguments[0], 1);
assert.sameValue(arguments[1], 2);
assert.sameValue(arguments[2], 3);
assert.sameValue(arguments[3], 4);
assert.sameValue(arguments[4], 5);