LibJS: Add TypedArray.prototype.@@iterator

Userland/Libraries/LibJS/Runtime/TypedArrayPrototype.cpp

@@ -61,6 +61,9 @@ void TypedArrayPrototype::initialize(GlobalObject& object)
 
     // 23.2.3.30 %TypedArray%.prototype.toString ( ), https://tc39.es/ecma262/#sec-%typedarray%.prototype.tostring
     define_direct_property(vm.names.toString, global_object().array_prototype()->get_without_side_effects(vm.names.toString), attr);
+
+    // 23.2.3.32 %TypedArray%.prototype [ @@iterator ] ( ), https://tc39.es/ecma262/#sec-%typedarray%.prototype-@@iterator
+    define_direct_property(*vm.well_known_symbol_iterator(), get_without_side_effects(vm.names.values), attr);
 }
 
 TypedArrayPrototype::~TypedArrayPrototype()

Userland/Libraries/LibJS/Tests/builtins/TypedArray/TypedArray.prototype.@@iterator.js

@@ -0,0 +1,89 @@
+const TYPED_ARRAYS = [
+    Uint8Array,
+    Uint8ClampedArray,
+    Uint16Array,
+    Uint32Array,
+    Int8Array,
+    Int16Array,
+    Int32Array,
+    Float32Array,
+    Float64Array,
+];
+
+const BIGINT_TYPED_ARRAYS = [BigUint64Array, BigInt64Array];
+
+const ALL_TYPED_ARRAYS = TYPED_ARRAYS.concat(BIGINT_TYPED_ARRAYS);
+
+describe("correct behavior", () => {
+    test("length is 0", () => {
+        ALL_TYPED_ARRAYS.forEach(T => {
+            expect(T.prototype[Symbol.iterator]).toHaveLength(0);
+        });
+    });
+
+    test("same value as %TypedArray%.prototype.values", () => {
+        ALL_TYPED_ARRAYS.forEach(T => {
+            expect(T.prototype[Symbol.iterator]).toBe(T.prototype.values);
+        });
+    });
+
+    test("basic functionality", () => {
+        TYPED_ARRAYS.forEach(T => {
+            const typedArray = new T([1, 2, 3]);
+            const iterator = typedArray[Symbol.iterator]();
+            expect(iterator.next()).toEqual({ value: 1, done: false });
+            expect(iterator.next()).toEqual({ value: 2, done: false });
+            expect(iterator.next()).toEqual({ value: 3, done: false });
+            expect(iterator.next()).toEqual({ value: undefined, done: true });
+            expect(iterator.next()).toEqual({ value: undefined, done: true });
+            expect(iterator.next()).toEqual({ value: undefined, done: true });
+        });
+
+        BIGINT_TYPED_ARRAYS.forEach(T => {
+            const typedArray = new T([1n, 2n, 3n]);
+            const iterator = typedArray[Symbol.iterator]();
+            expect(iterator.next()).toEqual({ value: 1n, done: false });
+            expect(iterator.next()).toEqual({ value: 2n, done: false });
+            expect(iterator.next()).toEqual({ value: 3n, done: false });
+            expect(iterator.next()).toEqual({ value: undefined, done: true });
+            expect(iterator.next()).toEqual({ value: undefined, done: true });
+            expect(iterator.next()).toEqual({ value: undefined, done: true });
+        });
+    });
+
+    test("can be iterated with for-of", () => {
+        TYPED_ARRAYS.forEach(T => {
+            const typedArray = new T([1, 2, 3]);
+            const result = [];
+
+            for (const value of typedArray) result.push(value);
+
+            expect(result).toHaveLength(3);
+            expect(result[0]).toBe(1);
+            expect(result[1]).toBe(2);
+            expect(result[2]).toBe(3);
+        });
+
+        BIGINT_TYPED_ARRAYS.forEach(T => {
+            const typedArray = new T([1n, 2n, 3n]);
+            const result = [];
+
+            for (const value of typedArray) result.push(value);
+
+            expect(result).toHaveLength(3);
+            expect(result[0]).toBe(1n);
+            expect(result[1]).toBe(2n);
+            expect(result[2]).toBe(3n);
+        });
+    });
+});
+
+describe("errors", () => {
+    test("this value must be a TypedArray object", () => {
+        ALL_TYPED_ARRAYS.forEach(T => {
+            expect(() => {
+                T.prototype[Symbol.iterator].call({});
+            }).toThrowWithMessage(TypeError, "Not an object of type TypedArray");
+        });
+    });
+});