Add TextEncoder/TextDecoder declaration

Author: jeskew

packages/util-utf8-browser/__tests__/index.ts

@@ -31,7 +31,7 @@ beforeEach(() => {
 
 describe('fromUtf8', () => {
     it('should use the Encoding API if available', () => {
-        TextEncoder = jest.fn() as any;
+        (global as any).TextEncoder = jest.fn() as any;
 
         fromUtf8('foo');
 
@@ -51,7 +51,7 @@ describe('fromUtf8', () => {
 
 describe('toUtf8', () => {
     it('should use the Encoding API if available', () => {
-        TextDecoder = jest.fn() as any;
+        (global as any).TextDecoder = jest.fn() as any;
 
         toUtf8(new Uint8Array(0));
 

packages/util-utf8-browser/__tests__/whatwgEncodingApi.ts

@@ -1,4 +1,7 @@
-import {fromUtf8, toUtf8} from '../lib/whatwgEncodingApi';
+import {
+    fromUtf8,
+    toUtf8,
+} from '../lib/whatwgEncodingApi';
 
 beforeEach(() => {
     const textDecoderInstance = {
@@ -8,10 +11,19 @@ beforeEach(() => {
         encode: jest.fn(() => new Uint8Array(0)),
     };
 
-    TextDecoder = jest.fn(() => textDecoderInstance) as any;
-    TextEncoder = jest.fn(() => textEncoderInstance) as any;
+    (global as any).TextDecoder = jest.fn(() => textDecoderInstance) as any;
+    (global as any).TextEncoder = jest.fn(() => textEncoderInstance) as any;
 });
 
+interface TextDecoderCtor {
+    new (): any;
+}
+interface TextEncoderCtor {
+    new (): any;
+}
+declare const TextDecoder: TextDecoderCtor;
+declare const TextEncoder: TextEncoderCtor;
+
 describe('WHATWG encoding spec compliant environment UTF-8 handling', () => {
     it('should use the global TextDecoder to decode UTF-8', () => {
         const decoder = new TextDecoder();

packages/util-utf8-browser/index.ts

@@ -7,6 +7,9 @@ import {
     toUtf8 as textEncoderToUtf8,
 } from './lib/whatwgEncodingApi';
 
+declare const TextDecoder: Function|undefined;
+declare const TextEncoder: Function|undefined;
+
 export function fromUtf8(input: string): Uint8Array {
     if (typeof TextEncoder === 'function') {
         return textEncoderFromUtf8(input);

packages/util-utf8-browser/lib/whatwgEncodingApi.ts

@@ -1,5 +1,48 @@
+/**
+ * A declaration of the global TextEncoder and TextDecoder constructors.
+ *
+ * @see https://encoding.spec.whatwg.org/
+ */
+namespace Encoding {
+    interface TextDecoderOptions {
+        fatal?: boolean;
+        ignoreBOM?: boolean;
+    }
+
+    interface TextDecodeOptions {
+        stream?: boolean;
+    }
+
+    interface TextDecoder {
+        readonly encoding: string;
+        readonly fatal: boolean;
+        readonly ignoreBOM: boolean;
+        decode(
+            input?: ArrayBuffer|ArrayBufferView,
+            options?: TextDecodeOptions
+        ): string;
+    }
+
+    export interface TextDecoderConstructor {
+        new (label?: string, options?: TextDecoderOptions): TextDecoder;
+    }
+
+    interface TextEncoder {
+        readonly encoding: 'utf-8';
+        encode(input?: string): Uint8Array;
+    }
+
+    export interface TextEncoderConstructor {
+        new (): TextEncoder;
+    }
+}
+
+declare const TextDecoder: Encoding.TextDecoderConstructor;
+
+declare const TextEncoder: Encoding.TextEncoderConstructor;
+
 export function fromUtf8(input: string): Uint8Array {
-    return new TextEncoder('utf-8').encode(input);
+    return new TextEncoder().encode(input);
 }
 
 export function toUtf8(input: Uint8Array): string {

packages/util-utf8-browser/package.json

@@ -14,14 +14,7 @@
   "devDependencies": {
     "@types/jest": "^19.2.2",
     "@types/node": "^7.0.12",
-    "@types/text-encoding": "0.0.30",
     "jest": "^19.0.2",
     "typescript": "^2.3"
-  },
-  "jest": {
-    "globals": {
-      "TextDecoder": true,
-      "TextEncoder": true
-    }
   }
 }

packages/util-utf8-browser/tsconfig.json

@@ -4,6 +4,7 @@
     "module": "commonjs",
     "declaration": true,
     "sourceMap": true,
-    "strict": true
+    "strict": true,
+    "stripInternal": true
   }
 }