feat: Add Typescript support

Author: olivierwilkinson

.eslintrc

@@ -1,13 +1,18 @@
 {
-  "extends": "./node_modules/kcd-scripts/eslint.js",
+  "parser": "@typescript-eslint/parser",
+  "extends": [
+    "plugin:@typescript-eslint/recommended",
+    "./node_modules/kcd-scripts/eslint.js"
+  ],
   "rules": {
     "babel/new-cap": "off",
     "func-names": "off",
     "babel/no-unused-expressions": "off",
     "prefer-arrow-callback": "off",
     "testing-library/no-await-sync-query": "off",
     "testing-library/no-dom-import": "off",
-    "testing-library/prefer-screen-queries": "off"
+    "testing-library/prefer-screen-queries": "off",
+    "@typescript-eslint/no-var-requires": "off"
   },
   "overrides": [
     {

README.md

@@ -138,6 +138,37 @@ it('lets you configure queries', async () => {
 })
 ```
 
+### Typescript
+
+All the above methods are fully typed. To use the Browser and Element commands
+added by `setupBrowser` the global `WebdriverIO` namespace will need to be
+modified. Add the following to a typescript module:
+
+```
+import {WebdriverIOQueries} from 'webdriverio-testing-library';
+
+declare global {
+  namespace WebdriverIO {
+    interface Browser extends WebdriverIOQueries {}
+    interface Element extends WebdriverIOQueries {}
+  }
+}
+```
+
+If you are using the `@wdio/sync` framework you will need to use the
+`WebdriverIOQueriesSync` type to extend the interfaces:
+
+```
+import {WebdriverIOQueriesSync} from 'webdriverio-testing-library';
+
+declare global {
+  namespace WebdriverIO {
+    interface Browser extends WebdriverIOQueriesSync {}
+    interface Element extends WebdriverIOQueriesSync {}
+  }
+}
+```
+
 ## Other Solutions
 
 I'm not aware of any, if you are please [make a pull request][prs] and add it

package.json

@@ -3,19 +3,18 @@
   "version": "1.1.0",
   "description": "",
   "main": "dist/index.js",
-  "typings": "typings",
+  "types": "dist/index.d.ts",
   "scripts": {
     "add-contributor": "kcd-scripts contributors add",
-    "build": "kcd-scripts build",
+    "build": "tsc -p tsconfig.build.json",
     "lint": "kcd-scripts lint",
     "test:unit": "kcd-scripts test --no-watch --config=jest.config.js",
     "validate": "kcd-scripts validate build,lint,test",
     "test": "wdio wdio.conf.js",
     "semantic-release": "semantic-release"
   },
   "files": [
-    "dist",
-    "typings"
+    "dist"
   ],
   "keywords": [],
   "author": "",
@@ -28,15 +27,19 @@
     "webdriverio": "*"
   },
   "devDependencies": {
+    "@typescript-eslint/eslint-plugin": "^4.14.0",
+    "@typescript-eslint/parser": "^4.14.0",
     "@wdio/cli": "^6.11.3",
     "@wdio/local-runner": "^6.12.0",
     "@wdio/mocha-framework": "^6.11.0",
     "@wdio/spec-reporter": "^6.11.0",
     "@wdio/sync": "^6.11.0",
     "chromedriver": "^87.0.5",
-    "eslint": "^6.5.1",
+    "eslint": "^7.6.0",
     "kcd-scripts": "^5.0.0",
     "semantic-release": "^17.0.2",
+    "ts-node": "^9.1.1",
+    "typescript": "^4.1.3",
     "wdio-chromedriver-service": "^6.0.4",
     "webdriverio": "^6.12.0"
   },

src/index.js renamed to src/index.ts

@@ -1,6 +1,19 @@
-const path = require('path')
-const fs = require('fs')
-const {queries: baseQueries} = require('@testing-library/dom')
+/* eslint-disable @typescript-eslint/no-implied-eval babel/no-invalid-this */
+
+import path from 'path'
+import fs from 'fs'
+import {queries as baseQueries} from '@testing-library/dom'
+import {Element, BrowserObject, MultiRemoteBrowserObject} from 'webdriverio'
+
+import {Config, QueryName, WebdriverIOQueries} from './types'
+
+declare global {
+  interface Window {
+    TestingLibraryDom: typeof baseQueries & {
+      configure: typeof configure
+    }
+  }
+}
 
 const DOM_TESTING_LIBRARY_UMD_PATH = path.join(
   require.resolve('@testing-library/dom'),
@@ -11,9 +24,9 @@ const DOM_TESTING_LIBRARY_UMD = fs
   .readFileSync(DOM_TESTING_LIBRARY_UMD_PATH)
   .toString()
 
-let _config
+let _config: Partial<Config>
 
-async function injectDOMTestingLibrary(container) {
+async function injectDOMTestingLibrary(container: Element) {
   await container.execute(DOM_TESTING_LIBRARY_UMD)
 
   if (_config) {
@@ -23,7 +36,7 @@ async function injectDOMTestingLibrary(container) {
   }
 }
 
-function serializeArgs(args) {
+function serializeArgs(args: any[]) {
   return args.map((arg) => {
     if (arg instanceof RegExp) {
       return {RegExp: arg.toString()}
@@ -35,10 +48,12 @@ function serializeArgs(args) {
   })
 }
 
-function executeQuery([query, container, ...args], done) {
-  const deserializedArgs = args.map((arg) => {
+function executeQuery(
+  [query, container, ...args]: [QueryName, HTMLElement, ...any[]],
+  done: (result: any) => void,
+) {
+  const [matcher, options, waitForOptions] = args.map((arg) => {
     if (arg && arg.RegExp) {
-      // eslint-disable-next-line
       return eval(arg.RegExp)
     }
     if (arg && arg.Undefined) {
@@ -48,7 +63,12 @@ function executeQuery([query, container, ...args], done) {
   })
 
   Promise.resolve(
-    window.TestingLibraryDom[query](container, ...deserializedArgs),
+    window.TestingLibraryDom[query](
+      container,
+      matcher,
+      options,
+      waitForOptions,
+    ),
   )
     .then(done)
     .catch((e) => done(e.message))
@@ -62,18 +82,18 @@ Element. There are valid WebElement JSONs that exclude the key but can be turned
 into Elements, such as { ELEMENT: elementId }; this can happen in setups that
 aren't generated by @wdio/cli.
 */
-function createElement(container, elementValue) {
+function createElement(container: Element, elementValue: any) {
   return container.$({
     'element-6066-11e4-a52e-4f735466cecf': '',
     ...elementValue,
   })
 }
 
-function createQuery(element, queryName) {
-  return async (...args) => {
+function createQuery(element: Element, queryName: string) {
+  return async (...args: any[]) => {
     await injectDOMTestingLibrary(element)
 
-    const result = await element.executeAsync(executeQuery, [
+    const result = await element.executeAsync<any[], any[]>(executeQuery, [
       queryName,
       element,
       ...serializeArgs(args),
@@ -95,17 +115,17 @@ function createQuery(element, queryName) {
   }
 }
 
-function within(element) {
+function within(element: Element) {
   return Object.keys(baseQueries).reduce(
     (queries, queryName) => ({
       ...queries,
       [queryName]: createQuery(element, queryName),
     }),
     {},
-  )
+  ) as WebdriverIOQueries
 }
 
-async function setupBrowser(browser) {
+async function setupBrowser(browser: BrowserObject | MultiRemoteBrowserObject) {
   const body = await browser.$('body')
   const queries = within(body)
 
@@ -117,8 +137,8 @@ async function setupBrowser(browser) {
     browser.addCommand(
       queryName,
       function (...args) {
-        // eslint-disable-next-line babel/no-invalid-this
-        return within(this)[queryName](...args)
+        // @ts-expect-error
+        return within(this as Element)[queryName](...args)
       },
       true,
     )
@@ -127,12 +147,9 @@ async function setupBrowser(browser) {
   return queries
 }
 
-function configure(config) {
+function configure(config: Partial<Config>) {
   _config = config
 }
 
-module.exports = {
-  within,
-  setupBrowser,
-  configure,
-}
+export * from './types'
+export {within, setupBrowser, configure}

src/types.ts

@@ -0,0 +1,43 @@
+import {
+  Config as BaseConfig,
+  BoundFunction as BoundFunctionBase,
+  queries,
+} from '@testing-library/dom'
+import {Element} from 'webdriverio'
+
+export type Config = Pick<BaseConfig, 'testIdAttribute'>
+
+export type WebdriverIOQueryReturnType<T> = T extends Promise<HTMLElement>
+  ? Element
+  : T extends HTMLElement
+  ? Element
+  : T extends Promise<HTMLElement[]>
+  ? Element[]
+  : T extends HTMLElement[]
+  ? Element[]
+  : T extends null
+  ? null
+  : never
+
+export type WebdriverIOBoundFunction<T> = (
+  ...params: Parameters<BoundFunctionBase<T>>
+) => Promise<WebdriverIOQueryReturnType<ReturnType<BoundFunctionBase<T>>>>
+
+export type WebdriverIOBoundFunctionSync<T> = (
+  ...params: Parameters<BoundFunctionBase<T>>
+) => WebdriverIOQueryReturnType<ReturnType<BoundFunctionBase<T>>>
+
+export type WebdriverIOBoundFunctions<T> = {
+  [P in keyof T]: WebdriverIOBoundFunction<T[P]>
+}
+
+export type WebdriverIOBoundFunctionsSync<T> = {
+  [P in keyof T]: WebdriverIOBoundFunctionSync<T[P]>
+}
+
+export type WebdriverIOQueries = WebdriverIOBoundFunctions<typeof queries>
+export type WebdriverIOQueriesSync = WebdriverIOBoundFunctionsSync<
+  typeof queries
+>
+
+export type QueryName = keyof typeof queries

test/configure.e2e.js renamed to test/configure.e2e.ts

@@ -1,11 +1,11 @@
-const {setupBrowser, configure} = require('../src')
+import {setupBrowser, configure} from '../src';
 
 describe('configure', () => {
   beforeEach(() => {
     configure({testIdAttribute: 'data-automation-id'})
   })
   afterEach(() => {
-    configure(null)
+    configure({})
   })
 
   it('supports alternative testIdAttribute', async () => {

test/queries.e2e.js renamed to test/queries.e2e.ts

@@ -1,11 +1,11 @@
-const {setupBrowser} = require('../src')
+import {setupBrowser} from '../src';
 
 describe('queries', () => {
   it('queryBy resolves with matching element', async () => {
     const {queryByText} = await setupBrowser(browser)
 
     const button = await queryByText('Unique Button Text')
-    expect(await button.getText()).toEqual('Unique Button Text')
+    expect(await button?.getText()).toEqual('Unique Button Text')
   })
 
   it('queryBy resolves with null when there are no matching elements', async () => {

test/setupBrowser.e2e.js renamed to test/setupBrowser.e2e.ts

@@ -1,6 +1,14 @@
-const {queries: baseQueries} = require('@testing-library/dom')
+import {queries as baseQueries} from '@testing-library/dom'
 
-const {setupBrowser} = require('../src')
+import {setupBrowser} from '../src'
+import { WebdriverIOQueries } from '../src/types'
+
+declare global {
+  namespace WebdriverIO {
+    interface Browser extends WebdriverIOQueries {}
+    interface Element extends WebdriverIOQueries {}
+  }
+}
 
 describe('setupBrowser', () => {
   it('resolves with all queries', async () => {
@@ -36,15 +44,15 @@ describe('setupBrowser', () => {
   })
 
   it('adds queries as browser commands', async () => {
-    await setupBrowser(browser);
+    await setupBrowser(browser)
 
     expect(await browser.getByText('Page Heading')).toBeDefined()
   })
 
   it('adds queries as element commands scoped to element', async () => {
-    await setupBrowser(browser);
+    await setupBrowser(browser)
 
-    const nested = await browser.$('*[data-testid="nested"]');
+    const nested = await browser.$('*[data-testid="nested"]')
     const button = await nested.getByText('Button Text')
     await button.click()
 

test/within.e2e.js renamed to test/within.e2e.ts

@@ -1,4 +1,4 @@
-const {within, setupBrowser} = require('../src')
+import {within, setupBrowser} from '../src';
 
 describe('within', () => {
   it('scopes queries to element', async () => {

tsconfig.build.json

@@ -0,0 +1,7 @@
+{
+  "extends": "./tsconfig.json",
+  "compilerOptions": {
+    "declaration": true
+  },
+  "exclude": ["test", "dist"]
+}

tsconfig.json

@@ -0,0 +1,12 @@
+{
+  "compilerOptions": {
+    "baseUrl": ".",
+    "target": "es2019",
+    "module": "commonjs",
+    "strict": true,
+    "esModuleInterop": true,
+    "declaration": true,
+    "outDir": "./dist",
+    "skipLibCheck": true
+  }
+}