LibJS: Add tests for %TypedArray%.prototype.with

Userland/Libraries/LibJS/Tests/builtins/TypedArray/TypedArray.prototype.with.js

@@ -0,0 +1,59 @@
+const TYPED_ARRAYS = [
+    Uint8Array,
+    Uint8ClampedArray,
+    Uint16Array,
+    Uint32Array,
+    Int8Array,
+    Int16Array,
+    Int32Array,
+    Float32Array,
+    Float64Array,
+];
+
+const BIGINT_TYPED_ARRAYS = [BigUint64Array, BigInt64Array];
+
+describe("normal behavior", () => {
+    test("length is 2", () => {
+        TYPED_ARRAYS.forEach(T => {
+            expect(T.prototype.with).toHaveLength(2);
+        });
+
+        BIGINT_TYPED_ARRAYS.forEach(T => {
+            expect(T.prototype.with).toHaveLength(2);
+        });
+    });
+
+    test("basic functionality", () => {
+        TYPED_ARRAYS.forEach(T => {
+            const a = new T([1, 2, 3, 4, 5]);
+            const values = [
+                [0, 10, [10, 2, 3, 4, 5]],
+                [-5, 10, [10, 2, 3, 4, 5]],
+                [4, 10, [1, 2, 3, 4, 10]],
+                [-1, 10, [1, 2, 3, 4, 10]],
+            ];
+            for (const [index, value, expected] of values) {
+                const b = a.with(index, value);
+                expect(a).not.toBe(b);
+                expect(a).toEqual([1, 2, 3, 4, 5]);
+                expect(b).toEqual(expected);
+            }
+        });
+
+        BIGINT_TYPED_ARRAYS.forEach(T => {
+            const a = new T([1n, 2n, 3n, 4n, 5n]);
+            const values = [
+                [0, 10n, [10n, 2n, 3n, 4n, 5n]],
+                [-5, 10n, [10n, 2n, 3n, 4n, 5n]],
+                [4, 10n, [1n, 2n, 3n, 4n, 10n]],
+                [-1, 10n, [1n, 2n, 3n, 4n, 10n]],
+            ];
+            for (const [index, value, expected] of values) {
+                const b = a.with(index, value);
+                expect(a).not.toBe(b);
+                expect(a).toEqual([1n, 2n, 3n, 4n, 5n]);
+                expect(b).toEqual(expected);
+            }
+        });
+    });
+});