Rename item() to at().

features.txt

@@ -189,9 +189,9 @@ Atomics.waitAsync
 
 # Item Method
 # https://github.com/tc39/proposal-item-method
-Array.prototype.item
+Array.prototype.at
-String.prototype.item
+String.prototype.at
-TypedArray.prototype.item
+TypedArray.prototype.at
 
 # Arbitrary module namespace names
 # https://github.com/tc39/ecma262/pull/2154

test/built-ins/Array/prototype/at/index-argument-tointeger.js

@@ -1,17 +1,17 @@
 // Copyright (C) 2020 Rick Waldron. All rights reserved.
 // This code is governed by the BSD license found in the LICENSE file.
 /*---
-esid: sec-array.prototype.item
+esid: sec-array.prototype.at
 description: >
   Property type and descriptor.
 info: |
-  Array.prototype.item( index )
+  Array.prototype.at( index )
 
   Let relativeIndex be ? ToInteger(index).
 
-features: [Array.prototype.item]
+features: [Array.prototype.at]
 ---*/
-assert.sameValue(typeof Array.prototype.item, 'function');
+assert.sameValue(typeof Array.prototype.at, 'function');
 
 let valueOfCallCount = 0;
 let index = {
@@ -23,5 +23,5 @@ let index = {
 
 let a = [0,1,2,3];
 
-assert.sameValue(a.item(index), 1, 'a.item({valueOf() {valueOfCallCount++; return 1;}}) must return 1');
+assert.sameValue(a.at(index), 1, 'a.at({valueOf() {valueOfCallCount++; return 1;}}) must return 1');
 assert.sameValue(valueOfCallCount, 1, 'The value of `valueOfCallCount` is 1');

test/built-ins/Array/prototype/at/index-non-numeric-argument-tointeger-invalid.js

@@ -1,20 +1,20 @@
 // Copyright (C) 2020 Rick Waldron. All rights reserved.
 // This code is governed by the BSD license found in the LICENSE file.
 /*---
-esid: sec-array.prototype.item
+esid: sec-array.prototype.at
 description: >
   Property type and descriptor.
 info: |
-  Array.prototype.item( index )
+  Array.prototype.at( index )
 
   Let relativeIndex be ? ToInteger(index).
 
-features: [Array.prototype.item]
+features: [Array.prototype.at]
 ---*/
-assert.sameValue(typeof Array.prototype.item, 'function');
+assert.sameValue(typeof Array.prototype.at, 'function');
 
 let a = [0,1,2,3];
 
 assert.throws(TypeError, () => {
-  a.item(Symbol());
+  a.at(Symbol());
-}, '`a.item(Symbol())` throws TypeError');
+}, '`a.at(Symbol())` throws TypeError');

test/built-ins/Array/prototype/at/index-non-numeric-argument-tointeger.js

@@ -0,0 +1,26 @@
+// Copyright (C) 2020 Rick Waldron. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-array.prototype.at
+description: >
+  Property type and descriptor.
+info: |
+  Array.prototype.at( index )
+
+  Let relativeIndex be ? ToInteger(index).
+
+features: [Array.prototype.at]
+---*/
+assert.sameValue(typeof Array.prototype.at, 'function');
+
+let a = [0,1,2,3];
+
+assert.sameValue(a.at(false), 0, 'a.at(false) must return 0');
+assert.sameValue(a.at(null), 0, 'a.at(null) must return 0');
+assert.sameValue(a.at(undefined), 0, 'a.at(undefined) must return 0');
+assert.sameValue(a.at(""), 0, 'a.at("") must return 0');
+assert.sameValue(a.at(function() {}), 0, 'a.at(function() {}) must return 0');
+assert.sameValue(a.at([]), 0, 'a.at([]) must return 0');
+
+assert.sameValue(a.at(true), 1, 'a.at(true) must return 1');
+assert.sameValue(a.at("1"), 1, 'a.at("1") must return 1');

test/built-ins/Array/prototype/at/length.js

@@ -0,0 +1,24 @@
+// Copyright (C) 2020 Rick Waldron. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-array.prototype.at
+description: >
+  Array.prototype.at.length value and descriptor.
+info: |
+  Array.prototype.at( index )
+
+  17 ECMAScript Standard Built-in Objects
+
+includes: [propertyHelper.js]
+features: [Array.prototype.at]
+---*/
+assert.sameValue(typeof Array.prototype.at, 'function');
+
+assert.sameValue(
+  Array.prototype.at.length, 1,
+  'The value of Array.prototype.at.length is 1'
+);
+
+verifyNotEnumerable(Array.prototype.at, 'length');
+verifyNotWritable(Array.prototype.at, 'length');
+verifyConfigurable(Array.prototype.at, 'length');

test/built-ins/Array/prototype/at/name.js

@@ -0,0 +1,24 @@
+// Copyright (C) 2020 Rick Waldron. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-array.prototype.at
+description: >
+  Array.prototype.at.name value and descriptor.
+info: |
+  Array.prototype.at( index )
+
+  17 ECMAScript Standard Built-in Objects
+
+includes: [propertyHelper.js]
+features: [Array.prototype.at]
+---*/
+assert.sameValue(typeof Array.prototype.at, 'function');
+
+assert.sameValue(
+  Array.prototype.at.name, 'item',
+  'The value of Array.prototype.at.name is "item"'
+);
+
+verifyNotEnumerable(Array.prototype.at, 'name');
+verifyNotWritable(Array.prototype.at, 'name');
+verifyConfigurable(Array.prototype.at, 'name');

test/built-ins/Array/prototype/at/prop-desc.js

@@ -1,22 +1,22 @@
 // Copyright (C) 2020 Rick Waldron. All rights reserved.
 // This code is governed by the BSD license found in the LICENSE file.
 /*---
-esid: sec-array.prototype.item
+esid: sec-array.prototype.at
 description: >
   Property type and descriptor.
 info: |
-  Array.prototype.item( index )
+  Array.prototype.at( index )
 
   17 ECMAScript Standard Built-in Objects
 includes: [propertyHelper.js]
-features: [Array.prototype.item]
+features: [Array.prototype.at]
 ---*/
-assert.sameValue(typeof Array.prototype.item, 'function');
+assert.sameValue(typeof Array.prototype.at, 'function');
 
 assert.sameValue(
-  typeof Array.prototype.item,
+  typeof Array.prototype.at,
   'function',
-  'The value of `typeof Array.prototype.item` is "function"'
+  'The value of `typeof Array.prototype.at` is "function"'
 );
 
 verifyNotEnumerable(Array.prototype, 'item');

test/built-ins/Array/prototype/at/return-abrupt-from-this.js

@@ -0,0 +1,22 @@
+// Copyright (C) 2020 Rick Waldron. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-array.prototype.at
+description: >
+  Return abrupt from ToObject(this value).
+info: |
+  Array.prototype.at( index )
+
+  Let O be ? ToObject(this value).
+
+features: [Array.prototype.at]
+---*/
+assert.sameValue(typeof Array.prototype.at, 'function');
+
+assert.throws(TypeError, () => {
+  Array.prototype.at.call(undefined);
+}, '`Array.prototype.at.call(undefined)` throws TypeError');
+
+assert.throws(TypeError, () => {
+  Array.prototype.at.call(null);
+}, '`Array.prototype.at.call(null)` throws TypeError');

test/built-ins/Array/prototype/at/returns-item-relative-index.js

@@ -1,7 +1,7 @@
 // Copyright (C) 2020 Rick Waldron. All rights reserved.
 // This code is governed by the BSD license found in the LICENSE file.
 /*---
-esid: sec-array.prototype.item
+esid: sec-array.prototype.at
 description: >
   Returns the item value at the specified relative index
 info: |
@@ -17,14 +17,14 @@ info: |
   If k < 0 or k ≥ len, then return undefined.
   Return ? Get(O, ! ToString(k)).
 
-features: [Array.prototype.item]
+features: [Array.prototype.at]
 ---*/
-assert.sameValue(typeof Array.prototype.item, 'function');
+assert.sameValue(typeof Array.prototype.at, 'function');
 
 let a = [1, 2, 3, 4, ,5];
 
-assert.sameValue(a.item(0), 1, 'a.item(0) must return 1');
+assert.sameValue(a.at(0), 1, 'a.at(0) must return 1');
-assert.sameValue(a.item(-1), 5, 'a.item(-1) must return 5');
+assert.sameValue(a.at(-1), 5, 'a.at(-1) must return 5');
-assert.sameValue(a.item(-2), undefined, 'a.item(-2) must return undefined');
+assert.sameValue(a.at(-2), undefined, 'a.at(-2) must return undefined');
-assert.sameValue(a.item(-3), 4, 'a.item(-3) must return 4');
+assert.sameValue(a.at(-3), 4, 'a.at(-3) must return 4');
-assert.sameValue(a.item(-4), 3, 'a.item(-4) must return 3');
+assert.sameValue(a.at(-4), 3, 'a.at(-4) must return 3');

test/built-ins/Array/prototype/at/returns-item.js

@@ -1,7 +1,7 @@
 // Copyright (C) 2020 Rick Waldron. All rights reserved.
 // This code is governed by the BSD license found in the LICENSE file.
 /*---
-esid: sec-array.prototype.item
+esid: sec-array.prototype.at
 description: >
   Returns the item value at the specified index
 info: |
@@ -17,15 +17,15 @@ info: |
   If k < 0 or k ≥ len, then return undefined.
   Return ? Get(O, ! ToString(k)).
 
-features: [Array.prototype.item]
+features: [Array.prototype.at]
 ---*/
-assert.sameValue(typeof Array.prototype.item, 'function');
+assert.sameValue(typeof Array.prototype.at, 'function');
 
 let a = [1, 2, 3, 4,,5];
 
-assert.sameValue(a.item(0), 1, 'a.item(0) must return 1');
+assert.sameValue(a.at(0), 1, 'a.at(0) must return 1');
-assert.sameValue(a.item(1), 2, 'a.item(1) must return 2');
+assert.sameValue(a.at(1), 2, 'a.at(1) must return 2');
-assert.sameValue(a.item(2), 3, 'a.item(2) must return 3');
+assert.sameValue(a.at(2), 3, 'a.at(2) must return 3');
-assert.sameValue(a.item(3), 4, 'a.item(3) must return 4');
+assert.sameValue(a.at(3), 4, 'a.at(3) must return 4');
-assert.sameValue(a.item(4), undefined, 'a.item(4) must return undefined');
+assert.sameValue(a.at(4), undefined, 'a.at(4) must return undefined');
-assert.sameValue(a.item(5), 5, 'a.item(5) must return 5');
+assert.sameValue(a.at(5), 5, 'a.at(5) must return 5');

test/built-ins/Array/prototype/at/returns-undefined-for-holes-in-sparse-arrays.js

@@ -0,0 +1,43 @@
+// Copyright (C) 2020 Rick Waldron. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-array.prototype.at
+description: >
+  Returns the item value at the specified index, respecting holes in sparse arrays.
+info: |
+  Array.prototypeitem ( )
+
+  Let O be ? ToObject(this value).
+  Let len be ? LengthOfArrayLike(O).
+  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)).
+
+features: [Array.prototype.at]
+---*/
+assert.sameValue(
+  typeof Array.prototype.at,
+  'function',
+  'The value of `typeof Array.prototype.at` is "function"'
+);
+
+let a = [0, 1, , 3, 4, , 6];
+
+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), undefined, 'a.at(2) must return undefined');
+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), undefined, 'a.at(5) must return undefined');
+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), undefined, 'a.at(-2) must return undefined');
+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), undefined, 'a.at(-5) must return undefined');
+assert.sameValue(a.at(-6), 1, 'a.at(-6) must return 1');

test/built-ins/Array/prototype/at/returns-undefined-for-out-of-range-index.js

@@ -0,0 +1,20 @@
+// Copyright (C) 2020 Rick Waldron. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-array.prototype.at
+description: >
+  Returns undefined if the specified index less than or greater than the available index range.
+info: |
+  Array.prototype.at( index )
+
+  If k < 0 or k ≥ len, then return undefined.
+features: [Array.prototype.at]
+---*/
+assert.sameValue(typeof Array.prototype.at, 'function');
+
+let a = [];
+
+assert.sameValue(a.at(-2), undefined, 'a.at(-2) must return undefined'); // wrap around the end
+assert.sameValue(a.at(0), undefined, 'a.at(0) must return undefined');
+assert.sameValue(a.at(1), undefined, 'a.at(1) must return undefined');
+

test/built-ins/Array/prototype/item/index-non-numeric-argument-tointeger.js

@@ -1,26 +0,0 @@
-// Copyright (C) 2020 Rick Waldron. All rights reserved.
-// This code is governed by the BSD license found in the LICENSE file.
-/*---
-esid: sec-array.prototype.item
-description: >
-  Property type and descriptor.
-info: |
-  Array.prototype.item( index )
-
-  Let relativeIndex be ? ToInteger(index).
-
-features: [Array.prototype.item]
----*/
-assert.sameValue(typeof Array.prototype.item, 'function');
-
-let a = [0,1,2,3];
-
-assert.sameValue(a.item(false), 0, 'a.item(false) must return 0');
-assert.sameValue(a.item(null), 0, 'a.item(null) must return 0');
-assert.sameValue(a.item(undefined), 0, 'a.item(undefined) must return 0');
-assert.sameValue(a.item(""), 0, 'a.item("") must return 0');
-assert.sameValue(a.item(function() {}), 0, 'a.item(function() {}) must return 0');
-assert.sameValue(a.item([]), 0, 'a.item([]) must return 0');
-
-assert.sameValue(a.item(true), 1, 'a.item(true) must return 1');
-assert.sameValue(a.item("1"), 1, 'a.item("1") must return 1');

test/built-ins/Array/prototype/item/length.js

@@ -1,24 +0,0 @@
-// Copyright (C) 2020 Rick Waldron. All rights reserved.
-// This code is governed by the BSD license found in the LICENSE file.
-/*---
-esid: sec-array.prototype.item
-description: >
-  Array.prototype.item.length value and descriptor.
-info: |
-  Array.prototype.item( index )
-
-  17 ECMAScript Standard Built-in Objects
-
-includes: [propertyHelper.js]
-features: [Array.prototype.item]
----*/
-assert.sameValue(typeof Array.prototype.item, 'function');
-
-assert.sameValue(
-  Array.prototype.item.length, 1,
-  'The value of Array.prototype.item.length is 1'
-);
-
-verifyNotEnumerable(Array.prototype.item, 'length');
-verifyNotWritable(Array.prototype.item, 'length');
-verifyConfigurable(Array.prototype.item, 'length');

test/built-ins/Array/prototype/item/name.js

@@ -1,24 +0,0 @@
-// Copyright (C) 2020 Rick Waldron. All rights reserved.
-// This code is governed by the BSD license found in the LICENSE file.
-/*---
-esid: sec-array.prototype.item
-description: >
-  Array.prototype.item.name value and descriptor.
-info: |
-  Array.prototype.item( index )
-
-  17 ECMAScript Standard Built-in Objects
-
-includes: [propertyHelper.js]
-features: [Array.prototype.item]
----*/
-assert.sameValue(typeof Array.prototype.item, 'function');
-
-assert.sameValue(
-  Array.prototype.item.name, 'item',
-  'The value of Array.prototype.item.name is "item"'
-);
-
-verifyNotEnumerable(Array.prototype.item, 'name');
-verifyNotWritable(Array.prototype.item, 'name');
-verifyConfigurable(Array.prototype.item, 'name');

test/built-ins/Array/prototype/item/return-abrupt-from-this.js

@@ -1,22 +0,0 @@
-// Copyright (C) 2020 Rick Waldron. All rights reserved.
-// This code is governed by the BSD license found in the LICENSE file.
-/*---
-esid: sec-array.prototype.item
-description: >
-  Return abrupt from ToObject(this value).
-info: |
-  Array.prototype.item( index )
-
-  Let O be ? ToObject(this value).
-
-features: [Array.prototype.item]
----*/
-assert.sameValue(typeof Array.prototype.item, 'function');
-
-assert.throws(TypeError, () => {
-  Array.prototype.item.call(undefined);
-}, '`Array.prototype.item.call(undefined)` throws TypeError');
-
-assert.throws(TypeError, () => {
-  Array.prototype.item.call(null);
-}, '`Array.prototype.item.call(null)` throws TypeError');

test/built-ins/Array/prototype/item/returns-undefined-for-holes-in-sparse-arrays.js

@@ -1,43 +0,0 @@
-// Copyright (C) 2020 Rick Waldron. All rights reserved.
-// This code is governed by the BSD license found in the LICENSE file.
-/*---
-esid: sec-array.prototype.item
-description: >
-  Returns the item value at the specified index, respecting holes in sparse arrays.
-info: |
-  Array.prototypeitem ( )
-
-  Let O be ? ToObject(this value).
-  Let len be ? LengthOfArrayLike(O).
-  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)).
-
-features: [Array.prototype.item]
----*/
-assert.sameValue(
-  typeof Array.prototype.item,
-  'function',
-  'The value of `typeof Array.prototype.item` is "function"'
-);
-
-let a = [0, 1, , 3, 4, , 6];
-
-assert.sameValue(a.item(0), 0, 'a.item(0) must return 0');
-assert.sameValue(a.item(1), 1, 'a.item(1) must return 1');
-assert.sameValue(a.item(2), undefined, 'a.item(2) must return undefined');
-assert.sameValue(a.item(3), 3, 'a.item(3) must return 3');
-assert.sameValue(a.item(4), 4, 'a.item(4) must return 4');
-assert.sameValue(a.item(5), undefined, 'a.item(5) must return undefined');
-assert.sameValue(a.item(6), 6, 'a.item(6) must return 6');
-assert.sameValue(a.item(-0), 0, 'a.item(-0) must return 0');
-assert.sameValue(a.item(-1), 6, 'a.item(-1) must return 6');
-assert.sameValue(a.item(-2), undefined, 'a.item(-2) must return undefined');
-assert.sameValue(a.item(-3), 4, 'a.item(-3) must return 4');
-assert.sameValue(a.item(-4), 3, 'a.item(-4) must return 3');
-assert.sameValue(a.item(-5), undefined, 'a.item(-5) must return undefined');
-assert.sameValue(a.item(-6), 1, 'a.item(-6) must return 1');

test/built-ins/Array/prototype/item/returns-undefined-for-out-of-range-index.js

@@ -1,20 +0,0 @@
-// Copyright (C) 2020 Rick Waldron. All rights reserved.
-// This code is governed by the BSD license found in the LICENSE file.
-/*---
-esid: sec-array.prototype.item
-description: >
-  Returns undefined if the specified index less than or greater than the available index range.
-info: |
-  Array.prototype.item( index )
-
-  If k < 0 or k ≥ len, then return undefined.
-features: [Array.prototype.item]
----*/
-assert.sameValue(typeof Array.prototype.item, 'function');
-
-let a = [];
-
-assert.sameValue(a.item(-2), undefined, 'a.item(-2) must return undefined'); // wrap around the end
-assert.sameValue(a.item(0), undefined, 'a.item(0) must return undefined');
-assert.sameValue(a.item(1), undefined, 'a.item(1) must return undefined');
-

test/built-ins/String/prototype/at/index-argument-tointeger.js

@@ -1,17 +1,17 @@
 // Copyright (C) 2020 Rick Waldron. All rights reserved.
 // This code is governed by the BSD license found in the LICENSE file.
 /*---
-esid: sec-string.prototype.item
+esid: sec-string.prototype.at
 description: >
   Property type and descriptor.
 info: |
-  String.prototype.item( index )
+  String.prototype.at( index )
 
   Let relativeIndex be ? ToInteger(index).
 
-features: [String.prototype.item]
+features: [String.prototype.at]
 ---*/
-assert.sameValue(typeof String.prototype.item, 'function');
+assert.sameValue(typeof String.prototype.at, 'function');
 
 let valueOfCallCount = 0;
 let index = {
@@ -23,5 +23,5 @@ let index = {
 
 let s = "01";
 
-assert.sameValue(s.item(index), '1', 's.item({valueOf() {valueOfCallCount++; return 1;}}) must return 1');
+assert.sameValue(s.at(index), '1', 's.at({valueOf() {valueOfCallCount++; return 1;}}) must return 1');
 assert.sameValue(valueOfCallCount, 1, 'The value of `valueOfCallCount` is 1');

test/built-ins/String/prototype/at/index-non-numeric-argument-tointeger-invalid.js

@@ -1,20 +1,20 @@
 // Copyright (C) 2020 Rick Waldron. All rights reserved.
 // This code is governed by the BSD license found in the LICENSE file.
 /*---
-esid: sec-string.prototype.item
+esid: sec-string.prototype.at
 description: >
   Property type and descriptor.
 info: |
-  String.prototype.item( index )
+  String.prototype.at( index )
 
   Let relativeIndex be ? ToInteger(index).
 
-features: [String.prototype.item]
+features: [String.prototype.at]
 ---*/
-assert.sameValue(typeof String.prototype.item, 'function');
+assert.sameValue(typeof String.prototype.at, 'function');
 
 let s = "01";
 
 assert.throws(TypeError, () => {
-  s.item(Symbol());
+  s.at(Symbol());
-}, '`s.item(Symbol())` throws TypeError');
+}, '`s.at(Symbol())` throws TypeError');

test/built-ins/String/prototype/at/index-non-numeric-argument-tointeger.js

@@ -0,0 +1,26 @@
+// Copyright (C) 2020 Rick Waldron. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-string.prototype.at
+description: >
+  Property type and descriptor.
+info: |
+  String.prototype.at( index )
+
+  Let relativeIndex be ? ToInteger(index).
+
+features: [String.prototype.at]
+---*/
+assert.sameValue(typeof String.prototype.at, 'function');
+
+let s = "01";
+
+assert.sameValue(s.at(false), '0', 's.at(false) must return 0');
+assert.sameValue(s.at(null), '0', 's.at(null) must return 0');
+assert.sameValue(s.at(undefined), '0', 's.at(undefined) must return 0');
+assert.sameValue(s.at(""), '0', 's.at("") must return 0');
+assert.sameValue(s.at(function() {}), '0', 's.at(function() {}) must return 0');
+assert.sameValue(s.at([]), '0', 's.at([]) must return 0');
+
+assert.sameValue(s.at(true), '1', 's.at(true) must return 1');
+assert.sameValue(s.at("1"), '1', 's.at("1") must return 1');

test/built-ins/String/prototype/at/length.js

@@ -0,0 +1,24 @@
+// Copyright (C) 2020 Rick Waldron. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-string.prototype.at
+description: >
+  String.prototype.at.length value and descriptor.
+info: |
+  String.prototype.at( index )
+
+  17 ECMAScript Standard Built-in Objects
+
+includes: [propertyHelper.js]
+features: [String.prototype.at]
+---*/
+assert.sameValue(typeof String.prototype.at, 'function');
+
+assert.sameValue(
+  String.prototype.at.length, 1,
+  'The value of String.prototype.at.length is 1'
+);
+
+verifyNotEnumerable(String.prototype.at, 'length');
+verifyNotWritable(String.prototype.at, 'length');
+verifyConfigurable(String.prototype.at, 'length');

test/built-ins/String/prototype/at/name.js

@@ -0,0 +1,24 @@
+// Copyright (C) 2020 Rick Waldron. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-string.prototype.at
+description: >
+  String.prototype.at.name value and descriptor.
+info: |
+  String.prototype.at( index )
+
+  17 ECMAScript Standard Built-in Objects
+
+includes: [propertyHelper.js]
+features: [String.prototype.at]
+---*/
+assert.sameValue(typeof String.prototype.at, 'function');
+
+assert.sameValue(
+  String.prototype.at.name, 'item',
+  'The value of String.prototype.at.name is "item"'
+);
+
+verifyNotEnumerable(String.prototype.at, 'name');
+verifyNotWritable(String.prototype.at, 'name');
+verifyConfigurable(String.prototype.at, 'name');

test/built-ins/String/prototype/at/prop-desc.js

@@ -1,22 +1,22 @@
 // Copyright (C) 2020 Rick Waldron. All rights reserved.
 // This code is governed by the BSD license found in the LICENSE file.
 /*---
-esid: sec-string.prototype.item
+esid: sec-string.prototype.at
 description: >
   Property type and descriptor.
 info: |
-  String.prototype.item( index )
+  String.prototype.at( index )
 
   17 ECMAScript Standard Built-in Objects
 includes: [propertyHelper.js]
-features: [String.prototype.item]
+features: [String.prototype.at]
 ---*/
-assert.sameValue(typeof String.prototype.item, 'function');
+assert.sameValue(typeof String.prototype.at, 'function');
 
 assert.sameValue(
-  typeof String.prototype.item,
+  typeof String.prototype.at,
   'function',
-  'The value of `typeof String.prototype.item` is "function"'
+  'The value of `typeof String.prototype.at` is "function"'
 );
 
 verifyNotEnumerable(String.prototype, 'item');

test/built-ins/String/prototype/at/return-abrupt-from-this.js

@@ -0,0 +1,22 @@
+// Copyright (C) 2020 Rick Waldron. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-string.prototype.at
+description: >
+  Return abrupt from RequireObjectCoercible(this value).
+info: |
+  String.prototype.at( index )
+
+  Let O be ? RequireObjectCoercible(this value).
+
+features: [String.prototype.at]
+---*/
+assert.sameValue(typeof String.prototype.at, 'function');
+
+assert.throws(TypeError, () => {
+  String.prototype.at.call(undefined);
+}, '`String.prototype.at.call(undefined)` throws TypeError');
+
+assert.throws(TypeError, () => {
+  String.prototype.at.call(null);
+}, '`String.prototype.at.call(null)` throws TypeError');

test/built-ins/String/prototype/at/returns-code-unit.js

@@ -1,7 +1,7 @@
 // Copyright (C) 2020 Rick Waldron. All rights reserved.
 // This code is governed by the BSD license found in the LICENSE file.
 /*---
-esid: sec-String.prototype.item
+esid: sec-String.prototype.at
 description: >
   The method should return an Iterator instance.
 info: |
@@ -17,14 +17,14 @@ info: |
   If k < 0 or k ≥ len, then return undefined.
   Return ? Get(O, ! ToString(k)).
 
-features: [String.prototype.item]
+features: [String.prototype.at]
 ---*/
-assert.sameValue(typeof String.prototype.item, 'function');
+assert.sameValue(typeof String.prototype.at, 'function');
 
 let s = "12\uD80034";
 
-assert.sameValue(s.item(0), "1", 's.item(0) must return "1"');
+assert.sameValue(s.at(0), "1", 's.at(0) must return "1"');
-assert.sameValue(s.item(1), "2", 's.item(1) must return "2"');
+assert.sameValue(s.at(1), "2", 's.at(1) must return "2"');
-assert.sameValue(s.item(2), "\uD800", 's.item(2) must return "\\uD800"');
+assert.sameValue(s.at(2), "\uD800", 's.at(2) must return "\\uD800"');
-assert.sameValue(s.item(3), "3", 's.item(3) must return "3"');
+assert.sameValue(s.at(3), "3", 's.at(3) must return "3"');
-assert.sameValue(s.item(4), "4", 's.item(4) must return "4"');
+assert.sameValue(s.at(4), "4", 's.at(4) must return "4"');

test/built-ins/String/prototype/at/returns-item-relative-index.js

@@ -17,13 +17,13 @@ info: |
   If k < 0 or k ≥ len, then return undefined.
   Return ? Get(O, ! ToString(k)).
 
-features: [String.prototype.item]
+features: [String.prototype.at]
 ---*/
-assert.sameValue(typeof String.prototype.item, 'function');
+assert.sameValue(typeof String.prototype.at, 'function');
 
 let s = "12345";
 
-assert.sameValue(s.item(0), "1", 's.item(0) must return "1"');
+assert.sameValue(s.at(0), "1", 's.at(0) must return "1"');
-assert.sameValue(s.item(-1), "5", 's.item(-1) must return "5"');
+assert.sameValue(s.at(-1), "5", 's.at(-1) must return "5"');
-assert.sameValue(s.item(-3), "3", 's.item(-3) must return "3"');
+assert.sameValue(s.at(-3), "3", 's.at(-3) must return "3"');
-assert.sameValue(s.item(-4), "2", 's.item(-4) must return "2"');
+assert.sameValue(s.at(-4), "2", 's.at(-4) must return "2"');

test/built-ins/String/prototype/at/returns-item.js

@@ -17,14 +17,14 @@ info: |
   If k < 0 or k ≥ len, then return undefined.
   Return ? Get(O, ! ToString(k)).
 
-features: [String.prototype.item]
+features: [String.prototype.at]
 ---*/
-assert.sameValue(typeof String.prototype.item, 'function');
+assert.sameValue(typeof String.prototype.at, 'function');
 
 let s = "12345";
 
-assert.sameValue(s.item(0), "1", 's.item(0) must return "1"');
+assert.sameValue(s.at(0), "1", 's.at(0) must return "1"');
-assert.sameValue(s.item(1), "2", 's.item(1) must return "2"');
+assert.sameValue(s.at(1), "2", 's.at(1) must return "2"');
-assert.sameValue(s.item(2), "3", 's.item(2) must return "3"');
+assert.sameValue(s.at(2), "3", 's.at(2) must return "3"');
-assert.sameValue(s.item(3), "4", 's.item(3) must return "4"');
+assert.sameValue(s.at(3), "4", 's.at(3) must return "4"');
-assert.sameValue(s.item(4), "5", 's.item(4) must return "5"');
+assert.sameValue(s.at(4), "5", 's.at(4) must return "5"');

test/built-ins/String/prototype/at/returns-undefined-for-out-of-range-index.js

@@ -0,0 +1,20 @@
+// Copyright (C) 2020 Rick Waldron. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-string.prototype.at
+description: >
+  Creates an iterator from a custom object.
+info: |
+  String.prototype.at( index )
+
+  If k < 0 or k ≥ len, then return undefined.
+features: [String.prototype.at]
+---*/
+assert.sameValue(typeof String.prototype.at, 'function');
+
+let s = "";
+
+assert.sameValue(s.at(-2), undefined, 's.at(-2) must return undefined'); // wrap around the end
+assert.sameValue(s.at(0), undefined, 's.at(0) must return undefined');
+assert.sameValue(s.at(1), undefined, 's.at(1) must return undefined');
+

test/built-ins/String/prototype/item/index-non-numeric-argument-tointeger.js

@@ -1,26 +0,0 @@
-// Copyright (C) 2020 Rick Waldron. All rights reserved.
-// This code is governed by the BSD license found in the LICENSE file.
-/*---
-esid: sec-string.prototype.item
-description: >
-  Property type and descriptor.
-info: |
-  String.prototype.item( index )
-
-  Let relativeIndex be ? ToInteger(index).
-
-features: [String.prototype.item]
----*/
-assert.sameValue(typeof String.prototype.item, 'function');
-
-let s = "01";
-
-assert.sameValue(s.item(false), '0', 's.item(false) must return 0');
-assert.sameValue(s.item(null), '0', 's.item(null) must return 0');
-assert.sameValue(s.item(undefined), '0', 's.item(undefined) must return 0');
-assert.sameValue(s.item(""), '0', 's.item("") must return 0');
-assert.sameValue(s.item(function() {}), '0', 's.item(function() {}) must return 0');
-assert.sameValue(s.item([]), '0', 's.item([]) must return 0');
-
-assert.sameValue(s.item(true), '1', 's.item(true) must return 1');
-assert.sameValue(s.item("1"), '1', 's.item("1") must return 1');

test/built-ins/String/prototype/item/length.js

@@ -1,24 +0,0 @@
-// Copyright (C) 2020 Rick Waldron. All rights reserved.
-// This code is governed by the BSD license found in the LICENSE file.
-/*---
-esid: sec-string.prototype.item
-description: >
-  String.prototype.item.length value and descriptor.
-info: |
-  String.prototype.item( index )
-
-  17 ECMAScript Standard Built-in Objects
-
-includes: [propertyHelper.js]
-features: [String.prototype.item]
----*/
-assert.sameValue(typeof String.prototype.item, 'function');
-
-assert.sameValue(
-  String.prototype.item.length, 1,
-  'The value of String.prototype.item.length is 1'
-);
-
-verifyNotEnumerable(String.prototype.item, 'length');
-verifyNotWritable(String.prototype.item, 'length');
-verifyConfigurable(String.prototype.item, 'length');

test/built-ins/String/prototype/item/name.js

@@ -1,24 +0,0 @@
-// Copyright (C) 2020 Rick Waldron. All rights reserved.
-// This code is governed by the BSD license found in the LICENSE file.
-/*---
-esid: sec-string.prototype.item
-description: >
-  String.prototype.item.name value and descriptor.
-info: |
-  String.prototype.item( index )
-
-  17 ECMAScript Standard Built-in Objects
-
-includes: [propertyHelper.js]
-features: [String.prototype.item]
----*/
-assert.sameValue(typeof String.prototype.item, 'function');
-
-assert.sameValue(
-  String.prototype.item.name, 'item',
-  'The value of String.prototype.item.name is "item"'
-);
-
-verifyNotEnumerable(String.prototype.item, 'name');
-verifyNotWritable(String.prototype.item, 'name');
-verifyConfigurable(String.prototype.item, 'name');

test/built-ins/String/prototype/item/return-abrupt-from-this.js

@@ -1,22 +0,0 @@
-// Copyright (C) 2020 Rick Waldron. All rights reserved.
-// This code is governed by the BSD license found in the LICENSE file.
-/*---
-esid: sec-string.prototype.item
-description: >
-  Return abrupt from RequireObjectCoercible(this value).
-info: |
-  String.prototype.item( index )
-
-  Let O be ? RequireObjectCoercible(this value).
-
-features: [String.prototype.item]
----*/
-assert.sameValue(typeof String.prototype.item, 'function');
-
-assert.throws(TypeError, () => {
-  String.prototype.item.call(undefined);
-}, '`String.prototype.item.call(undefined)` throws TypeError');
-
-assert.throws(TypeError, () => {
-  String.prototype.item.call(null);
-}, '`String.prototype.item.call(null)` throws TypeError');

test/built-ins/String/prototype/item/returns-undefined-for-out-of-range-index.js

@@ -1,20 +0,0 @@
-// Copyright (C) 2020 Rick Waldron. All rights reserved.
-// This code is governed by the BSD license found in the LICENSE file.
-/*---
-esid: sec-string.prototype.item
-description: >
-  Creates an iterator from a custom object.
-info: |
-  String.prototype.item( index )
-
-  If k < 0 or k ≥ len, then return undefined.
-features: [String.prototype.item]
----*/
-assert.sameValue(typeof String.prototype.item, 'function');
-
-let s = "";
-
-assert.sameValue(s.item(-2), undefined, 's.item(-2) must return undefined'); // wrap around the end
-assert.sameValue(s.item(0), undefined, 's.item(0) must return undefined');
-assert.sameValue(s.item(1), undefined, 's.item(1) must return undefined');
-

test/built-ins/TypedArray/prototype/at/index-argument-tointeger.js

@@ -1,25 +1,25 @@
 // 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.item
+esid: sec-%typedarray%.prototype.at
 description: >
   Property type and descriptor.
 info: |
-  %TypedArray%.prototype.item( index )
+  %TypedArray%.prototype.at( index )
 
   Let relativeIndex be ? ToInteger(index).
 
 includes: [testTypedArray.js]
-features: [TypedArray, TypedArray.prototype.item]
+features: [TypedArray, TypedArray.prototype.at]
 ---*/
 assert.sameValue(
-  typeof TypedArray.prototype.item,
+  typeof TypedArray.prototype.at,
   'function',
-  'The value of `typeof TypedArray.prototype.item` is "function"'
+  'The value of `typeof TypedArray.prototype.at` is "function"'
 );
 
 testWithTypedArrayConstructors(TA => {
-  assert.sameValue(typeof TA.prototype.item, 'function', 'The value of `typeof TA.prototype.item` is "function"');
+  assert.sameValue(typeof TA.prototype.at, 'function', 'The value of `typeof TA.prototype.at` is "function"');
   let valueOfCallCount = 0;
   let index = {
     valueOf() {
@@ -30,6 +30,6 @@ testWithTypedArrayConstructors(TA => {
 
   let a = new TA([0,1,2,3]);
 
-  assert.sameValue(a.item(index), 1, 'a.item({valueOf() {valueOfCallCount++; return 1;}}) must return 1');
+  assert.sameValue(a.at(index), 1, 'a.at({valueOf() {valueOfCallCount++; return 1;}}) must return 1');
   assert.sameValue(valueOfCallCount, 1, 'The value of `valueOfCallCount` is 1');
 });

test/built-ins/TypedArray/prototype/at/index-non-numeric-argument-tointeger-invalid.js

@@ -1,28 +1,28 @@
 // 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.item
+esid: sec-%typedarray%.prototype.at
 description: >
   Property type and descriptor.
 info: |
-  %TypedArray%.prototype.item( index )
+  %TypedArray%.prototype.at( index )
 
   Let relativeIndex be ? ToInteger(index).
 
 includes: [testTypedArray.js]
-features: [TypedArray, TypedArray.prototype.item]
+features: [TypedArray, TypedArray.prototype.at]
 ---*/
 assert.sameValue(
-  typeof TypedArray.prototype.item,
+  typeof TypedArray.prototype.at,
   'function',
-  'The value of `typeof TypedArray.prototype.item` is "function"'
+  'The value of `typeof TypedArray.prototype.at` is "function"'
 );
 
 testWithTypedArrayConstructors(TA => {
-  assert.sameValue(typeof TA.prototype.item, 'function', 'The value of `typeof TA.prototype.item` is "function"');
+  assert.sameValue(typeof TA.prototype.at, 'function', 'The value of `typeof TA.prototype.at` is "function"');
   let a = new TA([0,1,2,3]);
 
   assert.throws(TypeError, () => {
-    a.item(Symbol());
+    a.at(Symbol());
-  }, '`a.item(Symbol())` throws TypeError');
+  }, '`a.at(Symbol())` throws TypeError');
 });

test/built-ins/TypedArray/prototype/at/index-non-numeric-argument-tointeger.js

@@ -0,0 +1,35 @@
+// 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: >
+  Property type and descriptor.
+info: |
+  %TypedArray%.prototype.at( index )
+
+  Let relativeIndex be ? ToInteger(index).
+
+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 => {
+  assert.sameValue(typeof TA.prototype.at, 'function', 'The value of `typeof TA.prototype.at` is "function"');
+
+  let a = new TA([0,1,2,3]);
+
+  assert.sameValue(a.at(false), 0, 'a.at(false) must return 0');
+  assert.sameValue(a.at(null), 0, 'a.at(null) must return 0');
+  assert.sameValue(a.at(undefined), 0, 'a.at(undefined) must return 0');
+  assert.sameValue(a.at(""), 0, 'a.at("") must return 0');
+  assert.sameValue(a.at(function() {}), 0, 'a.at(function() {}) must return 0');
+  assert.sameValue(a.at([]), 0, 'a.at([]) must return 0');
+
+  assert.sameValue(a.at(true), 1, 'a.at(true) must return 1');
+  assert.sameValue(a.at("1"), 1, 'a.at("1") must return 1');
+});

test/built-ins/TypedArray/prototype/at/length.js

@@ -0,0 +1,28 @@
+// 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: >
+  TypedArray.prototype.at.length value and descriptor.
+info: |
+  %TypedArray%.prototype.at( index )
+
+  17 ECMAScript Standard Built-in Objects
+
+includes: [propertyHelper.js, testTypedArray.js]
+features: [TypedArray.prototype.at]
+---*/
+assert.sameValue(
+  typeof TypedArray.prototype.at,
+  'function',
+  'The value of `typeof TypedArray.prototype.at` is "function"'
+);
+
+assert.sameValue(
+  TypedArray.prototype.at.length, 1,
+  'The value of TypedArray.prototype.at.length is 1'
+);
+
+verifyNotEnumerable(TypedArray.prototype.at, 'length');
+verifyNotWritable(TypedArray.prototype.at, 'length');
+verifyConfigurable(TypedArray.prototype.at, 'length');

test/built-ins/TypedArray/prototype/at/name.js

@@ -0,0 +1,28 @@
+// 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: >
+  %TypedArray%.prototype.at.name value and descriptor.
+info: |
+  %TypedArray%.prototype.at( index )
+
+  17 ECMAScript Standard Built-in Objects
+
+includes: [propertyHelper.js, testTypedArray.js]
+features: [TypedArray.prototype.at]
+---*/
+assert.sameValue(
+  typeof TypedArray.prototype.at,
+  'function',
+  'The value of `typeof TypedArray.prototype.at` is "function"'
+);
+
+assert.sameValue(
+  TypedArray.prototype.at.name, 'item',
+  'The value of TypedArray.prototype.at.name is "item"'
+);
+
+verifyNotEnumerable(TypedArray.prototype.at, 'name');
+verifyNotWritable(TypedArray.prototype.at, 'name');
+verifyConfigurable(TypedArray.prototype.at, 'name');

test/built-ins/TypedArray/prototype/at/prop-desc.js

@@ -1,20 +1,20 @@
 // 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.item
+esid: sec-%typedarray%.prototype.at
 description: >
   Property type and descriptor.
 info: |
-  %TypedArray%.prototype.item( index )
+  %TypedArray%.prototype.at( index )
 
   17 ECMAScript Standard Built-in Objects
 includes: [propertyHelper.js, testTypedArray.js]
-features: [TypedArray.prototype.item]
+features: [TypedArray.prototype.at]
 ---*/
 assert.sameValue(
-  typeof TypedArray.prototype.item,
+  typeof TypedArray.prototype.at,
   'function',
-  'The value of `typeof TypedArray.prototype.item` is "function"'
+  'The value of `typeof TypedArray.prototype.at` is "function"'
 );
 
 verifyNotEnumerable(TypedArray.prototype, 'item');

test/built-ins/TypedArray/prototype/at/return-abrupt-from-this.js

@@ -0,0 +1,40 @@
+// 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: >
+  Return abrupt from ToObject(this value).
+info: |
+  %TypedArray%.prototype.at( index )
+
+  Let O be the this value.
+  Perform ? ValidateTypedArray(O).
+
+includes: [testTypedArray.js]
+features: [TypedArray,TypedArray.prototype.at]
+---*/
+assert.sameValue(
+  typeof TypedArray.prototype.at,
+  'function',
+  'The value of `typeof TypedArray.prototype.at` is "function"'
+);
+
+assert.throws(TypeError, () => {
+  TypedArray.prototype.at.call(undefined);
+}, '`TypedArray.prototype.at.call(undefined)` throws TypeError');
+
+assert.throws(TypeError, () => {
+  TypedArray.prototype.at.call(null);
+}, '`TypedArray.prototype.at.call(null)` throws TypeError');
+
+testWithTypedArrayConstructors(TA => {
+  assert.sameValue(typeof TA.prototype.at, 'function', 'The value of `typeof TA.prototype.at` is "function"');
+
+  assert.throws(TypeError, () => {
+    TA.prototype.at.call(undefined);
+  }, '`TA.prototype.at.call(undefined)` throws TypeError');
+
+  assert.throws(TypeError, () => {
+    TA.prototype.at.call(null);
+  }, '`TA.prototype.at.call(null)` throws TypeError');
+});

test/built-ins/TypedArray/prototype/at/returns-item-relative-index.js

@@ -1,11 +1,11 @@
 // 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.item
+esid: sec-%typedarray%.prototype.at
 description: >
   Returns the item value at the specified relative index
 info: |
-  %TypedArray%.prototype.item( index )
+  %TypedArray%.prototype.at( index )
 
   Let O be the this value.
   Perform ? ValidateTypedArray(O).
@@ -19,19 +19,19 @@ info: |
   Return ? Get(O, ! ToString(k)).
 
 includes: [testTypedArray.js]
-features: [TypedArray,TypedArray.prototype.item]
+features: [TypedArray,TypedArray.prototype.at]
 ---*/
 assert.sameValue(
-  typeof TypedArray.prototype.item,
+  typeof TypedArray.prototype.at,
   'function',
-  'The value of `typeof TypedArray.prototype.item` is "function"'
+  'The value of `typeof TypedArray.prototype.at` is "function"'
 );
 
 testWithTypedArrayConstructors(TA => {
   let a = new TA([1, 2, 3, 4, 5]);
-  assert.sameValue(a.item(0), 1, 'a.item(0) must return 1');
+  assert.sameValue(a.at(0), 1, 'a.at(0) must return 1');
-  assert.sameValue(a.item(-1), 5, 'a.item(-1) must return 5');
+  assert.sameValue(a.at(-1), 5, 'a.at(-1) must return 5');
-  assert.sameValue(a.item(-2), 4, 'a.item(-2) must return 4');
+  assert.sameValue(a.at(-2), 4, 'a.at(-2) must return 4');
-  assert.sameValue(a.item(-3), 3, 'a.item(-3) must return 3');
+  assert.sameValue(a.at(-3), 3, 'a.at(-3) must return 3');
-  assert.sameValue(a.item(-4), 2, 'a.item(-4) must return 2');
+  assert.sameValue(a.at(-4), 2, 'a.at(-4) must return 2');
 });

test/built-ins/TypedArray/prototype/at/returns-item.js

@@ -1,11 +1,11 @@
 // 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.item
+esid: sec-%typedarray%.prototype.at
 description: >
   Returns the item value at the specified index
 info: |
-  %TypedArray%.prototype.item( index )
+  %TypedArray%.prototype.at( index )
 
   Let O be the this value.
   Perform ? ValidateTypedArray(O).
@@ -19,20 +19,20 @@ info: |
   Return ? Get(O, ! ToString(k)).
 
 includes: [testTypedArray.js]
-features: [TypedArray,TypedArray.prototype.item]
+features: [TypedArray,TypedArray.prototype.at]
 ---*/
 assert.sameValue(
-  typeof TypedArray.prototype.item,
+  typeof TypedArray.prototype.at,
   'function',
-  'The value of `typeof TypedArray.prototype.item` is "function"'
+  'The value of `typeof TypedArray.prototype.at` is "function"'
 );
 
 testWithTypedArrayConstructors(TA => {
-  assert.sameValue(typeof TA.prototype.item, 'function', 'The value of `typeof TA.prototype.item` is "function"');
+  assert.sameValue(typeof TA.prototype.at, 'function', 'The value of `typeof TA.prototype.at` is "function"');
   let a = new TA([1, 2, 3, 4]);
 
-  assert.sameValue(a.item(0), 1, 'a.item(0) must return 1');
+  assert.sameValue(a.at(0), 1, 'a.at(0) must return 1');
-  assert.sameValue(a.item(1), 2, 'a.item(1) must return 2');
+  assert.sameValue(a.at(1), 2, 'a.at(1) must return 2');
-  assert.sameValue(a.item(2), 3, 'a.item(2) must return 3');
+  assert.sameValue(a.at(2), 3, 'a.at(2) must return 3');
-  assert.sameValue(a.item(3), 4, 'a.item(3) must return 4');
+  assert.sameValue(a.at(3), 4, 'a.at(3) must return 4');
 });

test/built-ins/TypedArray/prototype/at/returns-undefined-for-holes-in-sparse-arrays.js

@@ -0,0 +1,50 @@
+// 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');
+});

test/built-ins/TypedArray/prototype/at/returns-undefined-for-out-of-range-index.js

@@ -0,0 +1,28 @@
+// 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 undefined if the specified index less than or greater than the available index range.
+info: |
+  %TypedArray%.prototype.at( index )
+
+  If k < 0 or k ≥ len, then return undefined.
+
+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 => {
+  assert.sameValue(typeof TA.prototype.at, 'function', 'The value of `typeof TA.prototype.at` is "function"');
+  let a = new TA([]);
+
+  assert.sameValue(a.at(-2), undefined, 'a.at(-2) must return undefined'); // wrap around the end
+  assert.sameValue(a.at(0), undefined, 'a.at(0) must return undefined');
+  assert.sameValue(a.at(1), undefined, 'a.at(1) must return undefined');
+});

test/built-ins/TypedArray/prototype/item/index-non-numeric-argument-tointeger.js

@@ -1,35 +0,0 @@
-// 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.item
-description: >
-  Property type and descriptor.
-info: |
-  %TypedArray%.prototype.item( index )
-
-  Let relativeIndex be ? ToInteger(index).
-
-includes: [testTypedArray.js]
-features: [TypedArray, TypedArray.prototype.item]
----*/
-assert.sameValue(
-  typeof TypedArray.prototype.item,
-  'function',
-  'The value of `typeof TypedArray.prototype.item` is "function"'
-);
-
-testWithTypedArrayConstructors(TA => {
-  assert.sameValue(typeof TA.prototype.item, 'function', 'The value of `typeof TA.prototype.item` is "function"');
-
-  let a = new TA([0,1,2,3]);
-
-  assert.sameValue(a.item(false), 0, 'a.item(false) must return 0');
-  assert.sameValue(a.item(null), 0, 'a.item(null) must return 0');
-  assert.sameValue(a.item(undefined), 0, 'a.item(undefined) must return 0');
-  assert.sameValue(a.item(""), 0, 'a.item("") must return 0');
-  assert.sameValue(a.item(function() {}), 0, 'a.item(function() {}) must return 0');
-  assert.sameValue(a.item([]), 0, 'a.item([]) must return 0');
-
-  assert.sameValue(a.item(true), 1, 'a.item(true) must return 1');
-  assert.sameValue(a.item("1"), 1, 'a.item("1") must return 1');
-});

test/built-ins/TypedArray/prototype/item/length.js

@@ -1,28 +0,0 @@
-// 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.item
-description: >
-  TypedArray.prototype.item.length value and descriptor.
-info: |
-  %TypedArray%.prototype.item( index )
-
-  17 ECMAScript Standard Built-in Objects
-
-includes: [propertyHelper.js, testTypedArray.js]
-features: [TypedArray.prototype.item]
----*/
-assert.sameValue(
-  typeof TypedArray.prototype.item,
-  'function',
-  'The value of `typeof TypedArray.prototype.item` is "function"'
-);
-
-assert.sameValue(
-  TypedArray.prototype.item.length, 1,
-  'The value of TypedArray.prototype.item.length is 1'
-);
-
-verifyNotEnumerable(TypedArray.prototype.item, 'length');
-verifyNotWritable(TypedArray.prototype.item, 'length');
-verifyConfigurable(TypedArray.prototype.item, 'length');

test/built-ins/TypedArray/prototype/item/name.js

@@ -1,28 +0,0 @@
-// 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.item
-description: >
-  %TypedArray%.prototype.item.name value and descriptor.
-info: |
-  %TypedArray%.prototype.item( index )
-
-  17 ECMAScript Standard Built-in Objects
-
-includes: [propertyHelper.js, testTypedArray.js]
-features: [TypedArray.prototype.item]
----*/
-assert.sameValue(
-  typeof TypedArray.prototype.item,
-  'function',
-  'The value of `typeof TypedArray.prototype.item` is "function"'
-);
-
-assert.sameValue(
-  TypedArray.prototype.item.name, 'item',
-  'The value of TypedArray.prototype.item.name is "item"'
-);
-
-verifyNotEnumerable(TypedArray.prototype.item, 'name');
-verifyNotWritable(TypedArray.prototype.item, 'name');
-verifyConfigurable(TypedArray.prototype.item, 'name');

test/built-ins/TypedArray/prototype/item/return-abrupt-from-this.js

@@ -1,40 +0,0 @@
-// 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.item
-description: >
-  Return abrupt from ToObject(this value).
-info: |
-  %TypedArray%.prototype.item( index )
-
-  Let O be the this value.
-  Perform ? ValidateTypedArray(O).
-
-includes: [testTypedArray.js]
-features: [TypedArray,TypedArray.prototype.item]
----*/
-assert.sameValue(
-  typeof TypedArray.prototype.item,
-  'function',
-  'The value of `typeof TypedArray.prototype.item` is "function"'
-);
-
-assert.throws(TypeError, () => {
-  TypedArray.prototype.item.call(undefined);
-}, '`TypedArray.prototype.item.call(undefined)` throws TypeError');
-
-assert.throws(TypeError, () => {
-  TypedArray.prototype.item.call(null);
-}, '`TypedArray.prototype.item.call(null)` throws TypeError');
-
-testWithTypedArrayConstructors(TA => {
-  assert.sameValue(typeof TA.prototype.item, 'function', 'The value of `typeof TA.prototype.item` is "function"');
-
-  assert.throws(TypeError, () => {
-    TA.prototype.item.call(undefined);
-  }, '`TA.prototype.item.call(undefined)` throws TypeError');
-
-  assert.throws(TypeError, () => {
-    TA.prototype.item.call(null);
-  }, '`TA.prototype.item.call(null)` throws TypeError');
-});

test/built-ins/TypedArray/prototype/item/returns-undefined-for-holes-in-sparse-arrays.js

@@ -1,50 +0,0 @@
-// 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.item
-description: >
-  Returns the item value at the specified index, holes are filled in sparse arrays.
-info: |
-  %TypedArray%.prototype.item( 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.item]
----*/
-assert.sameValue(
-  typeof TypedArray.prototype.item,
-  'function',
-  'The value of `typeof TypedArray.prototype.item` 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.item(0), 0, 'a.item(0) must return 0');
-  assert.sameValue(a.item(1), 1, 'a.item(1) must return 1');
-  assert.sameValue(a.item(2), filler, 'a.item(2) must return the value of filler');
-  assert.sameValue(a.item(3), 3, 'a.item(3) must return 3');
-  assert.sameValue(a.item(4), 4, 'a.item(4) must return 4');
-  assert.sameValue(a.item(5), filler, 'a.item(5) must return the value of filler');
-  assert.sameValue(a.item(6), 6, 'a.item(6) must return 6');
-  assert.sameValue(a.item(-0), 0, 'a.item(-0) must return 0');
-  assert.sameValue(a.item(-1), 6, 'a.item(-1) must return 6');
-  assert.sameValue(a.item(-2), filler, 'a.item(-2) must return the value of filler');
-  assert.sameValue(a.item(-3), 4, 'a.item(-3) must return 4');
-  assert.sameValue(a.item(-4), 3, 'a.item(-4) must return 3');
-  assert.sameValue(a.item(-5), filler, 'a.item(-5) must return the value of filler');
-  assert.sameValue(a.item(-6), 1, 'a.item(-6) must return 1');
-});

test/built-ins/TypedArray/prototype/item/returns-undefined-for-out-of-range-index.js

@@ -1,28 +0,0 @@
-// 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.item
-description: >
-  Returns undefined if the specified index less than or greater than the available index range.
-info: |
-  %TypedArray%.prototype.item( index )
-
-  If k < 0 or k ≥ len, then return undefined.
-
-includes: [testTypedArray.js]
-features: [TypedArray,TypedArray.prototype.item]
----*/
-assert.sameValue(
-  typeof TypedArray.prototype.item,
-  'function',
-  'The value of `typeof TypedArray.prototype.item` is "function"'
-);
-
-testWithTypedArrayConstructors(TA => {
-  assert.sameValue(typeof TA.prototype.item, 'function', 'The value of `typeof TA.prototype.item` is "function"');
-  let a = new TA([]);
-
-  assert.sameValue(a.item(-2), undefined, 'a.item(-2) must return undefined'); // wrap around the end
-  assert.sameValue(a.item(0), undefined, 'a.item(0) must return undefined');
-  assert.sameValue(a.item(1), undefined, 'a.item(1) must return undefined');
-});