HTMLCollection-supported-property-indices.html

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This WPT test may be referenced by the following Test IDs:
- /dom/collections/HTMLCollection-supported-property-indices.html - WPT Dashboard Interop Dashboard

<!doctype html>

<meta charset=utf-8>

<title></title>

<script src=/resources/testharness.js></script>

<script src=/resources/testharnessreport.js></script>

<!-- We want to use a tag name that will not interact with our test harness,

     so just make one up.  "foo" is a good one -->

<!-- Ids that look like negative indices.  These should come first, so we can

     assert that lookups for nonnegative indices find these by index -->

<foo id="-2"></foo>

<foo id="-1"></foo>

<!-- Ids that look like nonnegative indices -->

<foo id="0"></foo>

<foo id="1"></foo>

<!-- Ids that look like nonnegative indices near 2^31 = 2147483648 -->

<foo id="2147483645"></foo> <!-- 2^31 - 3 -->

<foo id="2147483646"></foo> <!-- 2^31 - 2 -->

<foo id="2147483647"></foo> <!-- 2^31 - 1 -->

<foo id="2147483648"></foo> <!-- 2^31 -->

<foo id="2147483649"></foo> <!-- 2^31 + 1 -->

<!-- Ids that look like nonnegative indices near 2^32 = 4294967296 -->

<foo id="4294967293"></foo> <!-- 2^32 - 3 -->

<foo id="4294967294"></foo> <!-- 2^32 - 2 -->

<foo id="4294967295"></foo> <!-- 2^32 - 1 -->

<foo id="4294967296"></foo> <!-- 2^32 -->

<foo id="4294967297"></foo> <!-- 2^32 + 1 -->

<script>

test(function() {

  var collection = document.getElementsByTagName("foo");

  assert_equals(collection.item(-2), null);

  assert_equals(collection.item(-1), null);

  assert_equals(collection.namedItem(-2), document.getElementById("-2"));

  assert_equals(collection.namedItem(-1), document.getElementById("-1"));

  assert_equals(collection[-2], document.getElementById("-2"));

  assert_equals(collection[-1], document.getElementById("-1"));

}, "Handling of property names that look like negative integers");

test(function() {

  var collection = document.getElementsByTagName("foo");

  assert_equals(collection.item(0), document.getElementById("-2"));

  assert_equals(collection.item(1), document.getElementById("-1"));

  assert_equals(collection.namedItem(0), document.getElementById("0"));

  assert_equals(collection.namedItem(1), document.getElementById("1"));

  assert_equals(collection[0], document.getElementById("-2"));

  assert_equals(collection[1], document.getElementById("-1"));

}, "Handling of property names that look like small nonnegative integers");

test(function() {

  var collection = document.getElementsByTagName("foo");

  assert_equals(collection.item(2147483645), null);

  assert_equals(collection.item(2147483646), null);

  assert_equals(collection.item(2147483647), null);

  assert_equals(collection.item(2147483648), null);

  assert_equals(collection.item(2147483649), null);

  assert_equals(collection.namedItem(2147483645),

                document.getElementById("2147483645"));

  assert_equals(collection.namedItem(2147483646),

                document.getElementById("2147483646"));

  assert_equals(collection.namedItem(2147483647),

                document.getElementById("2147483647"));

  assert_equals(collection.namedItem(2147483648),

                document.getElementById("2147483648"));

  assert_equals(collection.namedItem(2147483649),

                document.getElementById("2147483649"));

  assert_equals(collection[2147483645], undefined);

  assert_equals(collection[2147483646], undefined);

  assert_equals(collection[2147483647], undefined);

  assert_equals(collection[2147483648], undefined);

  assert_equals(collection[2147483649], undefined);

}, "Handling of property names that look like integers around 2^31");

test(function() {

  var collection = document.getElementsByTagName("foo");

  assert_equals(collection.item(4294967293), null);

  assert_equals(collection.item(4294967294), null);

  assert_equals(collection.item(4294967295), null);

  assert_equals(collection.item(4294967296), document.getElementById("-2"));

  assert_equals(collection.item(4294967297), document.getElementById("-1"));

  assert_equals(collection.namedItem(4294967293),

                document.getElementById("4294967293"));

  assert_equals(collection.namedItem(4294967294),

                document.getElementById("4294967294"));

  assert_equals(collection.namedItem(4294967295),

                document.getElementById("4294967295"));

  assert_equals(collection.namedItem(4294967296),

                document.getElementById("4294967296"));

  assert_equals(collection.namedItem(4294967297),

                document.getElementById("4294967297"));

  assert_equals(collection[4294967293], undefined);

  assert_equals(collection[4294967294], undefined);

  assert_equals(collection[4294967295], document.getElementById("4294967295"));

  assert_equals(collection[4294967296], document.getElementById("4294967296"));

  assert_equals(collection[4294967297], document.getElementById("4294967297"));

}, "Handling of property names that look like integers around 2^32");

test(function() {

  var elements = document.getElementsByTagName("foo");

  var old_item = elements[0];

  var old_desc = Object.getOwnPropertyDescriptor(elements, 0);

  assert_equals(old_desc.value, old_item);

  assert_true(old_desc.enumerable);

  assert_true(old_desc.configurable);

  assert_false(old_desc.writable);

  elements[0] = 5;

  assert_equals(elements[0], old_item);

  assert_throws_js(TypeError, function() {

    "use strict";

    elements[0] = 5;

});

  assert_throws_js(TypeError, function() {

    Object.defineProperty(elements, 0, { value: 5 });

});

  delete elements[0];

  assert_equals(elements[0], old_item);

  assert_throws_js(TypeError, function() {

    "use strict";

    delete elements[0];

});

  assert_equals(elements[0], old_item);

}, 'Trying to set an expando that would shadow an already-existing indexed property');

test(function() {

  var elements = document.getElementsByTagName("foo");

  var idx = elements.length;

  var old_item = elements[idx];

  var old_desc = Object.getOwnPropertyDescriptor(elements, idx);

  assert_equals(old_item, undefined);

  assert_equals(old_desc, undefined);

  // [[DefineOwnProperty]] will disallow defining an indexed expando.

  elements[idx] = 5;

  assert_equals(elements[idx], undefined);

  assert_throws_js(TypeError, function() {

    "use strict";

    elements[idx] = 5;

});

  assert_throws_js(TypeError, function() {

    Object.defineProperty(elements, idx, { value: 5 });

});

  // Check that deletions out of range do not throw

  delete elements[idx];

  (function() {

    "use strict";

    delete elements[idx];

  })();

}, 'Trying to set an expando with an indexed property name past the end of the list');

test(function(){

  var elements = document.getElementsByTagName("foo");

  var old_item = elements[0];

  var old_desc = Object.getOwnPropertyDescriptor(elements, 0);

  assert_equals(old_desc.value, old_item);

  assert_true(old_desc.enumerable);

  assert_true(old_desc.configurable);

  assert_false(old_desc.writable);

  Object.prototype[0] = 5;

  this.add_cleanup(function () { delete Object.prototype[0]; });

  assert_equals(elements[0], old_item);

  delete elements[0];

  assert_equals(elements[0], old_item);

  assert_throws_js(TypeError, function() {

    "use strict";

    delete elements[0];

});

  assert_equals(elements[0], old_item);

}, 'Trying to delete an indexed property name should never work');

</script>