Add "Change Array by Copy" tests (stage 3)

features.txt

@@ -284,6 +284,11 @@ regexp-duplicate-named-groups
 # https://github.com/tc39/proposal-symbols-as-weakmap-keys
 symbols-as-weakmap-keys
 
+# Array.prototype.toReversed, Array.prototype.toSorted, Array.prototype.toSpliced,
+# Array.prototype.with and the equivalent TypedArray methods.
+# https://github.com/tc39/proposal-change-array-by-copy/
+change-array-by-copy
+
 ## Standard language features
 #
 # Language features that have been included in a published version of the

test/built-ins/Array/prototype/Symbol.unscopables/change-array-by-copy.js

@@ -0,0 +1,29 @@
+// Copyright (C) 2021 Igalia. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-array.prototype-@@unscopables
+description: >
+    Initial value of `Symbol.unscopables` property
+info: |
+    22.1.3.32 Array.prototype [ @@unscopables ]
+
+    ...
+    12. Perform ! CreateDataPropertyOrThrow(unscopableList, "toReversed", true).
+    13. Perform ! CreateDataPropertyOrThrow(unscopableList, "toSorted", true).
+    14. Perform ! CreateDataPropertyOrThrow(unscopableList, "toSpliced", true).
+    ...
+includes: [propertyHelper.js]
+features: [Symbol.unscopables, change-array-by-copy]
+---*/
+
+var unscopables = Array.prototype[Symbol.unscopables];
+
+for (const unscopable of ["toReversed", "toSorted", "toSpliced"]) {
+    verifyProperty(unscopables, unscopable, {
+        value: true,
+        writable: true,
+        configurable: true
+    })
+};
+
+assert.sameValue(Object.hasOwnProperty.call(unscopables, "with"), false, "does not have `with`");

test/built-ins/Array/prototype/toReversed/frozen-this-value.js

@@ -0,0 +1,18 @@
+// Copyright (C) 2021 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-array.prototype.toReversed
+description: >
+  Array.prototype.toReversed works on frozen objects
+features: [change-array-by-copy]
+includes: [compareArray.js]
+---*/
+
+var arr = Object.freeze([0, 1, 2]);
+var result = arr.toReversed();
+assert.compareArray(result, [2, 1, 0]);
+
+var arrayLike = Object.freeze({ length: 3, 0: 0, 1: 1, 2: 2 });
+result = Array.prototype.toReversed.call(arrayLike);
+assert.compareArray(result, [2, 1, 0]);

test/built-ins/Array/prototype/toReversed/get-descending-order.js

@@ -0,0 +1,49 @@
+// Copyright (C) 2021 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-array.prototype.toReversed
+description: >
+  Array.prototype.toReversed gets the array elements from the last one to the first one.
+info: |
+  Array.prototype.toReversed ( )
+
+  ...
+  2. Let len be ? LengthOfArrayLike(O).
+  ...
+  5. Repeat, while k < len
+    a. Let from be ! ToString(𝔽(len - k - 1)).
+    ...
+    c. Let fromValue be ? Get(O, from).
+    ...
+features: [change-array-by-copy]
+includes: [compareArray.js]
+---*/
+
+var order = [];
+var arrayLike = {
+  length: 3,
+  get 0() {
+    order.push(0);
+  },
+  get 1() {
+    order.push(1);
+  },
+  get 2() {
+    order.push(2);
+  },
+};
+
+Array.prototype.toReversed.call(arrayLike);
+
+assert.compareArray(order, [2, 1, 0]);
+
+order = [];
+var arr = [0, 1, 2];
+Object.defineProperty(arr, 0, { get: function() { order.push(0); } });
+Object.defineProperty(arr, 1, { get: function() { order.push(1); } });
+Object.defineProperty(arr, 2, { get: function() { order.push(2); } });
+
+Array.prototype.toReversed.call(arr);
+
+assert.compareArray(order, [2, 1, 0]);

test/built-ins/Array/prototype/toReversed/holes-not-preserved.js

@@ -0,0 +1,29 @@
+// Copyright (C) 2021 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-array.prototype.toReversed
+description: >
+  Array.prototype.toReversed does not preserve holes in the array
+info: |
+  Array.prototype.toReversed ( )
+
+  ...
+  2. Let len be ? LengthOfArrayLike(O).
+  ...
+  5. Repeat, while k < len
+    a. Let from be ! ToString(𝔽(len - k - 1)).
+    ...
+    c. Let fromValue be ? Get(O, from).
+    d. Perform ? CreateDataPropertyOrThrow(A, Pk, fromValue).
+    ...
+features: [change-array-by-copy]
+includes: [compareArray.js]
+---*/
+
+var arr = [0, /* hole */, 2, /* hole */, 4];
+Array.prototype[3] = 3;
+
+var reversed = arr.toReversed();
+assert.compareArray(reversed, [4, 3, 2, undefined, 0]);
+assert(reversed.hasOwnProperty(3));

test/built-ins/Array/prototype/toReversed/ignores-species.js

@@ -0,0 +1,31 @@
+// Copyright (C) 2021 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-array.prototype.toReversed
+description: >
+  Array.prototype.toReversed ignores @@species
+info: |
+  Array.prototype.toReversed ( )
+
+  ...
+  3. Let A be ? ArrayCreate(𝔽(len)).
+  ...
+features: [change-array-by-copy]
+---*/
+
+var a = [];
+a.constructor = {};
+a.constructor[Symbol.species] = function () {}
+
+assert.sameValue(Object.getPrototypeOf(a.toReversed()), Array.prototype);
+
+var b = [];
+
+Object.defineProperty(b, "constructor", {
+  get() {
+    throw new Test262Error("Should not get .constructor");
+  }
+});
+
+b.toReversed();

test/built-ins/Array/prototype/toReversed/immutable.js

@@ -0,0 +1,16 @@
+// Copyright (C) 2021 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-array.prototype.toReversed
+description: >
+  Array.prototype.toReversed does not mutate its this value
+features: [change-array-by-copy]
+includes: [compareArray.js]
+---*/
+
+var arr = [0, 1, 2];
+arr.toReversed();
+
+assert.compareArray(arr, [0, 1, 2]);
+assert.notSameValue(arr.toReversed(), arr);

test/built-ins/Array/prototype/toReversed/length-casted-to-zero.js

@@ -0,0 +1,20 @@
+// Copyright (C) 2021 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-array.prototype.toReversed
+description: >
+  Array.prototype.toReversed creates an empty array if the this value .length is not a positive integer.
+info: |
+  Array.prototype.toReversed ( )
+
+  ...
+  2. Let len be ? LengthOfArrayLike(O).
+  ...
+features: [change-array-by-copy]
+includes: [compareArray.js]
+---*/
+
+assert.compareArray(Array.prototype.toReversed.call({ length: -2 }), []);
+assert.compareArray(Array.prototype.toReversed.call({ length: "dog" }), []);
+assert.compareArray(Array.prototype.toReversed.call({ length: NaN }), []);

test/built-ins/Array/prototype/toReversed/length-decreased-while-iterating.js

@@ -0,0 +1,32 @@
+// Copyright (C) 2021 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-array.prototype.toReversed
+description: >
+  Array.prototype.toReversed caches the length getting the array elements.
+info: |
+  Array.prototype.toReversed ( )
+
+  ...
+  2. Let len be ? LengthOfArrayLike(O).
+  ...
+  5. Repeat, while k < len
+    ...
+    c. Let fromValue be ? Get(O, from).
+    ...
+features: [change-array-by-copy]
+includes: [compareArray.js]
+---*/
+
+var arr = [0, 1, 2, 3, 4];
+Array.prototype[1] = 5;
+
+Object.defineProperty(arr, "3", {
+  get() {
+    arr.length = 1;
+    return 3;
+  }
+});
+
+assert.compareArray(arr.toReversed(), [4, 3, undefined, 5, 0]);

test/built-ins/Array/prototype/toReversed/length-exceeding-array-length-limit.js

@@ -0,0 +1,38 @@
+// Copyright (C) 2021 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-array.prototype.toReversed
+description: >
+  Array.prototype.toReversed limits the length to 2 ** 32 - 1
+info: |
+  Array.prototype.toReversed ( )
+
+  ...
+  2. Let len be ? LengthOfArrayLike(O).
+  3. Let A be ? ArrayCreate(𝔽(len)).
+  ...
+
+  ArrayCreate ( length [, proto ] )
+
+  1. If length > 2 ** 32 - 1, throw a RangeError exception.
+features: [change-array-by-copy]
+---*/
+
+// Object with large "length" property
+var arrayLike = {
+  get "0"() {
+    throw new Test262Error("Get 0");
+  },
+  get "4294967295" () { // 2 ** 32 - 1
+    throw new Test262Error("Get 2147483648");
+  },
+  get "4294967296" () { // 2 ** 32
+    throw new Test262Error("Get 2147483648");
+  },
+  length: 2 ** 32
+};
+
+assert.throws(RangeError, function() {
+  Array.prototype.toReversed.call(arrayLike);
+});

test/built-ins/Array/prototype/toReversed/length-increased-while-iterating.js

@@ -0,0 +1,30 @@
+// Copyright (C) 2021 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-array.prototype.toReversed
+description: >
+  Array.prototype.toReversed caches the length getting the array elements.
+info: |
+  Array.prototype.toReversed ( )
+
+  ...
+  2. Let len be ? LengthOfArrayLike(O).
+  ...
+  5. Repeat, while k < len
+    ...
+    c. Let fromValue be ? Get(O, from).
+    ...
+features: [change-array-by-copy]
+includes: [compareArray.js]
+---*/
+
+var arr = [0, 1, 2];
+Object.defineProperty(arr, "0", {
+  get() {
+    arr.push(4);
+    return 0;
+  }
+});
+
+assert.compareArray(arr.toReversed(), [2, 1, 0]);

test/built-ins/Array/prototype/toReversed/length-tolength.js

@@ -0,0 +1,29 @@
+// Copyright (C) 2021 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-array.prototype.toReversed
+description: >
+  Array.prototype.toReversed converts the this value length to a number.
+info: |
+  Array.prototype.toReversed ( )
+
+  ...
+  2. Let len be ? LengthOfArrayLike(O).
+  ...
+features: [change-array-by-copy]
+includes: [compareArray.js]
+---*/
+
+assert.compareArray(Array.prototype.toReversed.call({ length: "2", 0: 1, 1: 2, 2: 3 }), [2, 1]);
+
+var arrayLike = {
+  length: {
+    valueOf: () => 2
+  },
+  0: 1,
+  1: 2,
+  2: 3,
+};
+
+assert.compareArray(Array.prototype.toReversed.call(arrayLike), [2, 1]);

test/built-ins/Array/prototype/toReversed/metadata/length.js

@@ -0,0 +1,30 @@
+// Copyright (C) 2021 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-array.prototype.toReversed
+description: >
+  The "length" property of Array.prototype.toReversed
+info: |
+  17 ECMAScript Standard Built-in Objects
+
+  Every built-in function object, including constructors, has a length property
+  whose value is an integer. Unless otherwise specified, this value is equal to
+  the largest number of named arguments shown in the subclause headings for the
+  function description. Optional parameters (which are indicated with brackets:
+  [ ]) or rest parameters (which are shown using the form «...name») are not
+  included in the default argument count.
+
+  Unless otherwise specified, the length property of a built-in function object
+  has the attributes { [[Writable]]: false, [[Enumerable]]: false,
+    [[Configurable]]: true }.
+includes: [propertyHelper.js]
+features: [change-array-by-copy]
+---*/
+
+verifyProperty(Array.prototype.toReversed, "length", {
+  value: 0,
+  writable: false,
+  enumerable: false,
+  configurable: true,
+});