Improve types of fill polyfill and test fallback

src/CharWidth.ts

@@ -3,7 +3,7 @@
  * @license MIT
  */
 
-import { fill } from './core/TypedArrayUtils';
+import { fill } from './common/TypedArrayUtils';
 
 export const wcwidth = (function(opts: {nul: number, control: number}): (ucs: number) => number {
  // extracted from https://www.cl.cam.ac.uk/%7Emgk25/ucs/wcwidth.c

src/common/TypedArrayUtils.test.ts

@@ -0,0 +1,89 @@
+/**
+ * Copyright (c) 2018 The xterm.js authors. All rights reserved.
+ * @license MIT
+ */
+import { assert } from 'chai';
+import { fillFallback } from './TypedArrayUtils';
+
+type TypedArray = Uint8Array | Uint16Array | Uint32Array | Uint8ClampedArray
+ | Int8Array | Int16Array | Int32Array
+ | Float32Array | Float64Array;
+
+describe('polyfill conformance tests', function(): void {
+
+ function deepEquals(a: TypedArray, b: TypedArray): void {
+ assert.equal(a.length, b.length);
+ for (let i = 0; i < a.length; ++i) {
+ assert.equal(a[i], b[i]);
+ }
+ }
+
+ describe('TypedArray.fill', function(): void {
+ it('should work with all typed array types', function(): void {
+ const u81 = new Uint8Array(5);
+ const u82 = new Uint8Array(5);
+ deepEquals(fillFallback(u81, 2), u82.fill(2));
+ deepEquals(fillFallback(u81, -1), u82.fill(-1));
+ const u161 = new Uint16Array(5);
+ const u162 = new Uint16Array(5);
+ deepEquals(fillFallback(u161, 2), u162.fill(2));
+ deepEquals(fillFallback(u161, 65535), u162.fill(65535));
+ deepEquals(fillFallback(u161, -1), u162.fill(-1));
+ const u321 = new Uint32Array(5);
+ const u322 = new Uint32Array(5);
+ deepEquals(fillFallback(u321, 2), u322.fill(2));
+ deepEquals(fillFallback(u321, 65537), u322.fill(65537));
+ deepEquals(fillFallback(u321, -1), u322.fill(-1));
+ const i81 = new Int8Array(5);
+ const i82 = new Int8Array(5);
+ deepEquals(fillFallback(i81, 2), i82.fill(2));
+ deepEquals(fillFallback(i81, -1), i82.fill(-1));
+ const i161 = new Int16Array(5);
+ const i162 = new Int16Array(5);
+ deepEquals(fillFallback(i161, 2), i162.fill(2));
+ deepEquals(fillFallback(i161, 65535), i162.fill(65535));
+ deepEquals(fillFallback(i161, -1), i162.fill(-1));
+ const i321 = new Int32Array(5);
+ const i322 = new Int32Array(5);
+ deepEquals(fillFallback(i321, 2), i322.fill(2));
+ deepEquals(fillFallback(i321, 65537), i322.fill(65537));
+ deepEquals(fillFallback(i321, -1), i322.fill(-1));
+ const f321 = new Float32Array(5);
+ const f322 = new Float32Array(5);
+ deepEquals(fillFallback(f321, 1.2345), f322.fill(1.2345));
+ const f641 = new Float64Array(5);
+ const f642 = new Float64Array(5);
+ deepEquals(fillFallback(f641, 1.2345), f642.fill(1.2345));
+ const u8Clamped1 = new Uint8ClampedArray(5);
+ const u8Clamped2 = new Uint8ClampedArray(5);
+ deepEquals(fillFallback(u8Clamped1, 2), u8Clamped2.fill(2));
+ deepEquals(fillFallback(u8Clamped1, 257), u8Clamped2.fill(257));
+ });
+ it('start offset', function(): void {
+ for (let i = -2; i < 10; ++i) {
+ const u81 = new Uint8Array(5);
+ const u83 = new Uint8Array(5);
+ deepEquals(fillFallback(u81, 2, i), u83.fill(2, i));
+ deepEquals(fillFallback(u81, -1, i), u83.fill(-1, i));
+ }
+ });
+ it('end offset', function(): void {
+ for (let i = -2; i < 10; ++i) {
+ const u81 = new Uint8Array(5);
+ const u83 = new Uint8Array(5);
+ deepEquals(fillFallback(u81, 2, 0, i), u83.fill(2, 0, i));
+ deepEquals(fillFallback(u81, -1, 0, i), u83.fill(-1, 0, i));
+ }
+ });
+ it('start/end offset', function(): void {
+ for (let i = -2; i < 10; ++i) {
+ for (let j = -2; j < 10; ++j) {
+ const u81 = new Uint8Array(5);
+ const u83 = new Uint8Array(5);
+ deepEquals(fillFallback(u81, 2, i, j), u83.fill(2, i, j));
+ deepEquals(fillFallback(u81, -1, i, j), u83.fill(-1, i, j));
+ }
+ }
+ });
+ });
+});

src/core/TypedArrayUtils.ts → src/common/TypedArrayUtils.ts

@@ -12,11 +12,15 @@ type TypedArray = Uint8Array | Uint16Array | Uint32Array | Uint8ClampedArray
  | Int8Array | Int16Array | Int32Array
  | Float32Array | Float64Array;
 
-export function fill(array: TypedArray, value: number, start: number = 0, end?: number | undefined): TypedArray {
+export function fill<T extends TypedArray>(array: T, value: number, start?: number, end?: number): T {
  // all modern engines that support .fill
  if (array.fill) {
- return array.fill(value, start, end);
+ return array.fill(value, start, end) as T;
  }
+ return fillFallback(array, value, start, end);
+}
+
+export function fillFallback<T extends TypedArray>(array: T, value: number, start: number = 0, end: number = array.length): T {
  // safari and IE 11
  // since IE 11 does not support Array.prototype.fill either
  // we cannot use the suggested polyfill from MDN
@@ -25,9 +29,6 @@ export function fill(array: TypedArray, value: number, start: number = 0, end?:
  return array;
  }
  start = (array.length + start) % array.length;
- if (end === undefined) {
- end = array.length;
- }
  if (end >= array.length) {
  end = array.length;
  } else {