<!DOCTYPE html>
<script src="../resources/testharness.js"></script>
<script src="../resources/testharnessreport.js"></script>
<script>
function createIterable(iterations) {
  return {
    [Symbol.iterator]() {
      var i = 0;
      return {next: () => iterations[i++]};
    },
  };
}

function assertIterationJoinEqual(iterable, description) {
  test(() => {
    assert_equals(internals.dictionaryTest().stringFromIterable(iterable), Array.from(iterable).join(','));
  }, description);
}

assertIterationJoinEqual([1, 2, 3], 'Standard array of numbers.');
assertIterationJoinEqual(new Set([1, 2, 3]), 'Standard set of numbers.');
assertIterationJoinEqual([], 'Standard empty array.');
assertIterationJoinEqual(new Set(), 'Standard empty set.');

assertIterationJoinEqual(createIterable([
  {done: false, value: 1},
  {done: false, value: 2},
  {done: false, value: 3},
  {done: true},
]), 'Custom list of numbers.');

assertIterationJoinEqual(createIterable([
  {done: false, value: 1},
  {done: false, value: 2},
  {done: false, value: 3},
  {done: 'yes'},
]), 'Truthy done signal.');

assertIterationJoinEqual(createIterable([
  {value: 1},
  {value: 2},
  {value: 3},
  {done: true},
]), 'Custom list of numbers with missing "done: false" signal.');

assertIterationJoinEqual(createIterable([
  {done: false, value: 1},
  {done: false, value: 2},
  {done: true},
  {done: false, value: 3},
]), 'Terminates when done is true.');

assertIterationJoinEqual(createIterable([
  {done: true},
]), 'Empty list.');

assertIterationJoinEqual({}, 'Non-iterable object.');

test(() => {
  var iterable = {[Symbol.iterator]() { return {}; }};
  assert_throws(null, () => Array.from(iterable));
  assert_throws(null, () => internals.dictionaryTest().stringFromIterable(iterable));
}, 'Iterator object without next() function should throw.');

test(() => {
  var iterable = createIterable([
    {done: false, value: 1},
    {done: false, value: 2},
    {done: false, value: 3},
    1234,
  ]);
  assert_throws(null, () => Array.from(iterable));
  assert_throws(null, () => internals.dictionaryTest().stringFromIterable(iterable));
}, 'Non-object iterator.next() result should throw.');
</script>