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diff --git a/js/src/tests/test262/built-ins/TypedArray/prototype/at/returns-undefined-for-holes-in-sparse-arrays.js b/js/src/tests/test262/built-ins/TypedArray/prototype/at/returns-undefined-for-holes-in-sparse-arrays.js
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+++ b/js/src/tests/test262/built-ins/TypedArray/prototype/at/returns-undefined-for-holes-in-sparse-arrays.js
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+// Copyright (C) 2020 Rick Waldron. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-%typedarray%.prototype.at
+description: >
+  Returns the item value at the specified index, holes are filled in sparse arrays.
+info: |
+  %TypedArray%.prototype.at( index )
+
+  Let O be the this value.
+  Perform ? ValidateTypedArray(O).
+  Let len be O.[[ArrayLength]].
+  Let relativeIndex be ? ToInteger(index).
+  If relativeIndex ≥ 0, then
+    Let k be relativeIndex.
+  Else,
+    Let k be len + relativeIndex.
+  If k < 0 or k ≥ len, then return undefined.
+  Return ? Get(O, ! ToString(k)).
+
+includes: [testTypedArray.js]
+features: [TypedArray, TypedArray.prototype.at]
+---*/
+assert.sameValue(
+  typeof TypedArray.prototype.at,
+  'function',
+  'The value of `typeof TypedArray.prototype.at` is "function"'
+);
+
+testWithTypedArrayConstructors(TA => {
+  let a = new TA([0, 1, , 3, 4, , 6]);
+  let filler = 0;
+  if (TA.name.startsWith('Float')) {
+    filler = NaN;
+  }
+  assert.sameValue(a.at(0), 0, 'a.at(0) must return 0');
+  assert.sameValue(a.at(1), 1, 'a.at(1) must return 1');
+  assert.sameValue(a.at(2), filler, 'a.at(2) must return the value of filler');
+  assert.sameValue(a.at(3), 3, 'a.at(3) must return 3');
+  assert.sameValue(a.at(4), 4, 'a.at(4) must return 4');
+  assert.sameValue(a.at(5), filler, 'a.at(5) must return the value of filler');
+  assert.sameValue(a.at(6), 6, 'a.at(6) must return 6');
+  assert.sameValue(a.at(-0), 0, 'a.at(-0) must return 0');
+  assert.sameValue(a.at(-1), 6, 'a.at(-1) must return 6');
+  assert.sameValue(a.at(-2), filler, 'a.at(-2) must return the value of filler');
+  assert.sameValue(a.at(-3), 4, 'a.at(-3) must return 4');
+  assert.sameValue(a.at(-4), 3, 'a.at(-4) must return 3');
+  assert.sameValue(a.at(-5), filler, 'a.at(-5) must return the value of filler');
+  assert.sameValue(a.at(-6), 1, 'a.at(-6) must return 1');
+});
+
+reportCompare(0, 0);