feat(tool function): add autoPolyfill()

README.md

@@ -69,7 +69,7 @@ if (global && typeof global.Promise !== 'function') {
 - 可自定义 Promise 实现，直接扩展已有的 Promise 构造函数。
 - 工具函数
   - [x] initPromise()
-  - [ ] autoPolyfill()
+  - [x] autoPolyfill()
 - 静态方法
   - [x] Promise.all()
   - [x] Promise.race()
@@ -104,7 +104,15 @@ const PromisePlus = initPromise(CustomPromise)
 
 #### autoPolyfill()
 
-// TODO
+自动对当前运行环境进行 Promise Polyfill。  
+如果全局没有 Promise 支持，则会直接将内置的 Promise 实现挂载到全局；  
+如果全局已有 Promise 支持，则会对现有的 Promise 进行扩展后挂载到全局。  
+
+```javascript
+import { autoPolyfill } from 'promise-polyfill-plus'
+
+autoPolyfill()
+```
 
 ### 静态方法
 

README_EN.md

@@ -68,7 +68,7 @@ if (global && typeof global.Promise !== 'function') {
 - It can customize promise implementation and directly extend existing promise constructors.
 - Tool function
   - [x] initPromise()
-  - [ ] autoPolyfill()
+  - [x] autoPolyfill()
 - Static method
   - [x] Promise.all()
   - [x] Promise.race()
@@ -103,7 +103,15 @@ const PromisePlus = initPromise(CustomPromise)
 
 #### autoPolyfill()
 
-// TODO
+Promise polyfill for the current operating environment automatically.  
+If there is no global Promise support, the built-in Promise will be directly mounted to the global;  
+If there is global Promise support, the existing Promise will be expanded and mounted to the global.  
+
+```javascript
+import { autoPolyfill } from 'promise-polyfill-plus'
+
+autoPolyfill()
+```
 
 ### Static method
 

package.json

@@ -67,6 +67,7 @@
     "husky": "^4.3.6",
     "jest": "^26.6.3",
     "jest-config": "^26.6.3",
+    "jest-environment-node": "^26.6.2",
     "lint-staged": "^10.5.3",
     "lodash.camelcase": "^4.3.0",
     "prettier": "^2.2.1",

src/helpers/util.ts

@@ -15,6 +15,26 @@ export function isPromiseLike(val: any): val is PromiseLike<any> {
   )
 }
 
+/**
+ * 判断是否是 PromiseConstructorLike 的对象。
+ * @param promiseClass
+ */
+export function isPromiseConstructorLike(
+  promiseClass: any
+): promiseClass is PromiseConstructorLike {
+  try {
+    const instance = new promiseClass(() => {
+      // do nothing
+    })
+    if (!isPromiseLike(instance)) {
+      return false
+    }
+  } catch (err) {
+    return false
+  }
+  return true
+}
+
 /**
  * 判断是否是内置的 Promise 构造函数产生的 promise 对象。
  * @param val 需要判断的对象

src/index.ts

@@ -4,7 +4,7 @@ import Promise from './promise-polyfill-plus'
 export * from './types'
 
 // 导出构建方法
-export { initPromise } from './promise-polyfill-plus'
+export { initPromise, autoPolyfill } from './promise-polyfill-plus'
 
 // 导出主体
 export default Promise

src/promise-polyfill-plus.ts

@@ -1,5 +1,5 @@
 import { MyPromiseStatic } from './types'
-import { isPromiseLike } from './helpers/util'
+import { isPromiseConstructorLike } from './helpers/util'
 import MyPromise from './core/MyPromise'
 import initAll from './lib/all'
 import initRace from './lib/race'
@@ -26,17 +26,10 @@ const staticMethods = {
  * @param promiseClass
  */
 export function initPromise(promiseClass: PromiseConstructorLike) {
-  try {
-    const instance = new promiseClass(() => {
-      // do nothing
-    })
-    if (!isPromiseLike(instance)) {
-      throw new TypeError(
-        `Init param ${promiseClass} is not a PromiseConstructorLike object`
-      )
-    }
-  } catch (err) {
-    throw err
+  if (!isPromiseConstructorLike(promiseClass)) {
+    throw new TypeError(
+      `Init param ${promiseClass} is not a PromiseConstructorLike object`
+    )
   }
   Object.keys(staticMethods).forEach(key => {
     if (typeof (promiseClass as any)[key] !== 'function') {
@@ -48,4 +41,16 @@ export function initPromise(promiseClass: PromiseConstructorLike) {
 
 const Promise = initPromise(MyPromise)
 
+/**
+ * 自动 Polyfill 当前运行环境的 Promise
+ */
+export function autoPolyfill() {
+  const env = typeof window !== 'undefined' ? window : global
+  if (env.Promise && isPromiseConstructorLike(env.Promise)) {
+    ;(env as any).Promise = initPromise(env.Promise)
+  } else {
+    ;(env as any).Promise = Promise
+  }
+}
+
 export default Promise

test/MyPromise-init.spec.ts

@@ -1,4 +1,4 @@
-import MyPromise, { initPromise } from '../src/index'
+import MyPromise, { initPromise, autoPolyfill } from '../src/index'
 
 /**
  * 实例化测试
@@ -50,17 +50,29 @@ describe('init function test', () => {
   })
 
   it('should not be added method', () => {
-    const newPromise = initPromise(Promise)
-    expect(newPromise.all).not.toEqual(MyPromise.all)
-    expect(newPromise.race).not.toEqual(MyPromise.race)
-    expect(newPromise.resolve).not.toEqual(MyPromise.resolve)
-    expect(newPromise.reject).not.toEqual(MyPromise.reject)
+    const newPromiseClass = initPromise(Promise)
+    expect(newPromiseClass.all).not.toEqual(MyPromise.all)
+    expect(newPromiseClass.race).not.toEqual(MyPromise.race)
+    expect(newPromiseClass.resolve).not.toEqual(MyPromise.resolve)
+    expect(newPromiseClass.reject).not.toEqual(MyPromise.reject)
   })
 
   it('should be added method', () => {
-    const newPromise = initPromise(Promise)
-    expect(newPromise.deferred).not.toBeUndefined()
-    expect(newPromise.allSettled).not.toBeUndefined()
-    expect(newPromise.try).not.toBeUndefined()
+    const newPromiseClass = initPromise(Promise)
+    expect(newPromiseClass.deferred).not.toBeUndefined()
+    expect(newPromiseClass.allSettled).not.toBeUndefined()
+    expect(newPromiseClass.any).not.toBeUndefined()
+    expect(newPromiseClass.try).not.toBeUndefined()
+  })
+})
+
+describe('init function test', () => {
+  it('should be added method', () => {
+    autoPolyfill()
+    const EnvPromise: any = Promise
+    expect(EnvPromise.deferred).not.toBeUndefined()
+    expect(EnvPromise.allSettled).not.toBeUndefined()
+    expect(EnvPromise.any).not.toBeUndefined()
+    expect(EnvPromise.try).not.toBeUndefined()
   })
 })

test/env/no-promise-environment.js

@@ -0,0 +1,19 @@
+// no-promise-environment
+const NodeEnvironment = require('jest-environment-node')
+
+class NoPromiseEnvironment extends NodeEnvironment {
+  constructor(config, context) {
+    super(config, context)
+    this.testPath = context.testPath
+    this.docblockPragmas = context.docblockPragmas
+  }
+  async setup() {
+    await super.setup()
+
+    setTimeout(()=>{
+      this.global.Promise = undefined
+    })
+  }
+}
+
+module.exports = NoPromiseEnvironment

test/no_promise_env.spec.ts

@@ -0,0 +1,19 @@
+/**
+ * @jest-environment ./test/env/no-promise-environment
+ */
+
+import { autoPolyfill } from '../src'
+
+describe('init function test in no promise env', () => {
+  it('should be added method', done => {
+    setTimeout(() => {
+      autoPolyfill()
+      const EnvPromise: any = Promise
+      expect(EnvPromise.deferred).not.toBeUndefined()
+      expect(EnvPromise.allSettled).not.toBeUndefined()
+      expect(EnvPromise.any).not.toBeUndefined()
+      expect(EnvPromise.try).not.toBeUndefined()
+      done()
+    })
+  })
+})