├── .env
├── .github
└── workflows
│ ├── badges.yml
│ └── test.yml
├── .gitignore
├── .npmrc
├── README.md
├── cypress.json
├── cypress
├── fixtures
│ └── example.json
├── integration
│ └── spec.js
├── plugins
│ └── index.js
└── support
│ └── index.js
├── images
├── coverage-object.png
├── coverage.png
├── test.png
├── utils-coverage.png
└── yarn-report.png
├── package.json
├── public
├── favicon.ico
├── index.html
├── logo192.png
├── logo512.png
├── manifest.json
└── robots.txt
├── renovate.json
├── src
├── App.css
├── App.test.tsx
├── App.tsx
├── index.css
├── index.tsx
├── logo.svg
├── react-app-env.d.ts
├── serviceWorker.ts
├── setupTests.ts
└── utils.tsx
├── tsconfig.json
└── yarn.lock
/.env:
--------------------------------------------------------------------------------
1 | BROWSER=none
2 | SKIP_PREFLIGHT_CHECK=true
3 |
--------------------------------------------------------------------------------
/.github/workflows/badges.yml:
--------------------------------------------------------------------------------
1 | name: badges
2 | # update README badges only if the README file changes
3 | # or if the package.json file changes, or this file changes
4 | on:
5 | push:
6 | branches:
7 | - master
8 | paths:
9 | - README.md
10 | - package.json
11 | - .github/workflows/badges.yml
12 |
13 | jobs:
14 | build:
15 | name: Badges
16 | runs-on: ubuntu-latest
17 | steps:
18 | - name: Checkout 🛎
19 | uses: actions/checkout@v1
20 |
21 | - name: Install dependencies 📦
22 | uses: cypress-io/github-action@v1
23 | with:
24 | # just perform install
25 | runTests: false
26 |
27 | - name: Update version badges 🏷
28 | run: yarn update-badge cypress @cypress/instrument-cra @cypress/code-coverage
29 |
30 | # commit any changed files
31 | # https://github.com/mikeal/publish-to-github-action
32 | - name: Push any changes to repo 📤
33 | uses: mikeal/publish-to-github-action@master
34 | env:
35 | GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
36 |
--------------------------------------------------------------------------------
/.github/workflows/test.yml:
--------------------------------------------------------------------------------
1 | name: test
2 | on: [push]
3 | jobs:
4 | cypress-run:
5 | runs-on: ubuntu-latest
6 | steps:
7 | - name: Checkout 🛎
8 | uses: actions/checkout@v1
9 | # Install NPM dependencies, cache them correctly
10 | # and run all Cypress tests
11 | - name: Cypress run 🧪
12 | uses: cypress-io/github-action@v1
13 | with:
14 | start: npm start
15 | wait-on: 'http://localhost:3000'
16 | # nyc does not do very strict code coverage
17 | # the file could be empty and the check would still pass
18 | - name: check code coverage 📈
19 | run: npx nyc report --check-coverage --lines 88
20 | - name: strict code coverage 📊
21 | run: |
22 | npx check-coverage App.tsx
23 | npx check-coverage index.tsx
24 | npx only-covered App.tsx index.tsx utils.tsx
25 |
--------------------------------------------------------------------------------
/.gitignore:
--------------------------------------------------------------------------------
1 | # See https://help.github.com/articles/ignoring-files/ for more about ignoring files.
2 |
3 | # dependencies
4 | /node_modules
5 | /.pnp
6 | .pnp.js
7 |
8 | # testing
9 | /coverage
10 |
11 | # production
12 | /build
13 |
14 | # misc
15 | .DS_Store
16 | .env.local
17 | .env.development.local
18 | .env.test.local
19 | .env.production.local
20 |
21 | npm-debug.log*
22 | yarn-debug.log*
23 | yarn-error.log*
24 | .nyc_output
25 |
--------------------------------------------------------------------------------
/.npmrc:
--------------------------------------------------------------------------------
1 | package-lock=false
2 | save-exact=true
3 |
--------------------------------------------------------------------------------
/README.md:
--------------------------------------------------------------------------------
1 | # cra-ts-code-coverage-example [![renovate-app badge][renovate-badge]][renovate-app] [](.github/workflows/test.yml)
2 | > React App with TypeScript and Cypress code coverage
3 |
4 | This project was created using CRA v3
5 |
6 | ```shell
7 | $ npm i -g create-react-app
8 | + create-react-app@3.3.1
9 | $ create-react-app cra-ts-code-coverage-example --template typescript
10 | ```
11 |
12 | ## Current dependencies
13 |
14 | Name | Description
15 | --- | ---
16 |  | Cypress test runner [cypress-io/cypress](https://github.com/cypress-io/cypress)
17 |  | Instruments `react-scripts` applications on the fly
18 |  | Generates coverage reports after Cypress test runs
19 |
20 |
21 | ## Cypress tests with code coverage
22 |
23 | Add Cypress and code coverage report plugin
24 |
25 | ```shell
26 | $ yarn add -D cypress @cypress/code-coverage
27 | info Direct dependencies
28 | ├─ @cypress/code-coverage@3.7.2
29 | └─ cypress@4.5.0
30 | ```
31 |
32 | Add library to instrument application code on the fly
33 |
34 | ```shell
35 | $ yarn add -D @cypress/instrument-cra
36 | info Direct dependencies
37 | └─ @cypress/instrument-cra@1.1.0
38 | ```
39 |
40 | Change the `start` script in [package.json](package.json) to be `react-scripts -r @cypress/instrument-cra start`. If you start application now, there should be object `window.__coverage__` with code coverage numbers.
41 |
42 | 
43 |
44 | Watch video [How to instrument react-scripts web application for code coverage](https://youtu.be/edgeQZ8UpD0)
45 |
46 | ### Set up coverage plugin
47 |
48 | In [cypress/support/index.js](cypress/support/index.js) add line
49 |
50 | ```js
51 | import '@cypress/code-coverage/support'
52 | ```
53 |
54 | In [cypress/plugins/index.js](cypress/plugins/index.js) log the coverage plugin
55 |
56 | ```js
57 | module.exports = (on, config) => {
58 | require('@cypress/code-coverage/task')(on, config)
59 | // IMPORTANT to return the config object
60 | // with the any changed environment variables
61 | return config
62 | }
63 | ```
64 |
65 | Hint: check [cypress-io/code-coverage](https://github.com/cypress-io/code-coverage) README for current installation instructions.
66 |
67 | Watch video [Get code coverage reports from Cypress tests](https://youtu.be/y8StkffYra0)
68 |
69 | ### Run tests
70 |
71 | Start app and Cypress
72 |
73 | ```shell
74 | $ yarn add -D start-server-and-test
75 | info Direct dependencies
76 | └─ start-server-and-test@1.10.8
77 | ```
78 |
79 | In [package.json](package.json)
80 |
81 | ```json
82 | {
83 | "scripts": {
84 | "start": "react-scripts -r @cypress/instrument-cra start",
85 | "cy:open": "cypress open",
86 | "dev": "start-test 3000 cy:open"
87 | }
88 | }
89 | ```
90 |
91 | Tip: watch video [Using start-server-and-test to start app, run tests and shut everything down](https://youtu.be/mYXXSvcmQ6Y)
92 |
93 | Start Cypress with `npm run dev` and run a single end-to-end test [cypress/integration/spec.js](cypress/integration/spec.js)
94 |
95 | ```js
96 | it('opens the app', () => {
97 | cy.visit('/')
98 | cy.get('header.App-header').should('be.visible')
99 | cy.contains('Learn tcaeR').should('be.visible')
100 | })
101 | ```
102 |
103 | 
104 |
105 | The code coverage information is saved automatically in the folder `.nyc_output`. Run `nyc` tool to see summary in the terminal
106 |
107 | ```shell
108 | $ yarn nyc report
109 | ```
110 |
111 | 
112 |
113 | Or open generated static code coverage report with `open coverage/lcov-report/index.html`
114 |
115 | 
116 |
117 | You can drill into individual files
118 |
119 | 
120 |
121 | You can see the app has never called `add(a, b)` function, and only has called the `reverse(s)` function once passing a string.
122 |
123 | ## See also
124 |
125 | For more examples, see [cypress-io/code-coverage](https://github.com/cypress-io/code-coverage#examples) and read the Cypress [Code Coverage Guide](http://on.cypress.io/code-coverage). You can also watch [Cypress.io - State of the Art Testing Tool](https://www.youtube.com/watch?v=JL3QKQO80fs) presentation and see its [slides](https://slides.com/bahmutov/state-of-the-art).
126 |
127 | Watch series of short videos [Cypress tips & tricks](https://www.youtube.com/playlist?list=PLP9o9QNnQuAYYRpJzDNWpeuOVTwxmIxcI)
128 |
129 | [renovate-badge]: https://img.shields.io/badge/renovate-app-blue.svg
130 | [renovate-app]: https://renovateapp.com/
131 |
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/cypress.json:
--------------------------------------------------------------------------------
1 | {
2 | "baseUrl": "http://localhost:3000"
3 | }
4 |
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/cypress/fixtures/example.json:
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1 | {
2 | "name": "Using fixtures to represent data",
3 | "email": "hello@cypress.io",
4 | "body": "Fixtures are a great way to mock data for responses to routes"
5 | }
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/cypress/integration/spec.js:
--------------------------------------------------------------------------------
1 | ///
2 | it('opens the app', () => {
3 | cy.visit('/')
4 | cy.get('header.App-header').should('be.visible')
5 | cy.contains('Learn tcaeR').should('be.visible')
6 | })
7 |
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/cypress/plugins/index.js:
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1 | module.exports = (on, config) => {
2 | require('@cypress/code-coverage/task')(on, config)
3 | // IMPORTANT to return the config object
4 | // with the any changed environment variables
5 | return config
6 | }
7 |
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/cypress/support/index.js:
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1 | import '@cypress/code-coverage/support'
2 |
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/package.json:
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1 | {
2 | "name": "cra-ts-code-coverage-example",
3 | "description": "React App with TypeScript and Cypress code coverage",
4 | "version": "0.1.0",
5 | "private": true,
6 | "dependencies": {
7 | "@testing-library/jest-dom": "4.2.4",
8 | "@testing-library/react": "9.5.0",
9 | "@testing-library/user-event": "7.2.1",
10 | "@types/jest": "24.9.1",
11 | "@types/node": "12.12.30",
12 | "@types/react": "16.9.25",
13 | "@types/react-dom": "16.9.5",
14 | "react": "16.13.1",
15 | "react-dom": "16.13.1",
16 | "react-scripts": "3.4.1",
17 | "typescript": "3.8.3"
18 | },
19 | "scripts": {
20 | "start": "react-scripts -r @cypress/instrument-cra start",
21 | "build": "react-scripts build",
22 | "test": "react-scripts test",
23 | "eject": "react-scripts eject",
24 | "cy:open": "cypress open",
25 | "dev": "start-test 3000 cy:open"
26 | },
27 | "eslintConfig": {
28 | "extends": "react-app"
29 | },
30 | "nyc": {
31 | "exclude": [
32 | "src/serviceWorker.ts"
33 | ]
34 | },
35 | "browserslist": {
36 | "production": [
37 | ">0.2%",
38 | "not dead",
39 | "not op_mini all"
40 | ],
41 | "development": [
42 | "last 1 chrome version",
43 | "last 1 firefox version",
44 | "last 1 safari version"
45 | ]
46 | },
47 | "devDependencies": {
48 | "@cypress/code-coverage": "3.8.3",
49 | "@cypress/instrument-cra": "1.4.0",
50 | "check-code-coverage": "1.0.1",
51 | "cypress": "4.12.1",
52 | "dependency-version-badge": "1.2.0",
53 | "start-server-and-test": "1.11.5"
54 | }
55 | }
56 |
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/public/index.html:
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1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
12 |
13 |
17 |
18 |
27 | React App
28 |
29 |
30 |
31 |
32 |
42 |
43 |
44 |
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/public/manifest.json:
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1 | {
2 | "short_name": "React App",
3 | "name": "Create React App Sample",
4 | "icons": [
5 | {
6 | "src": "favicon.ico",
7 | "sizes": "64x64 32x32 24x24 16x16",
8 | "type": "image/x-icon"
9 | },
10 | {
11 | "src": "logo192.png",
12 | "type": "image/png",
13 | "sizes": "192x192"
14 | },
15 | {
16 | "src": "logo512.png",
17 | "type": "image/png",
18 | "sizes": "512x512"
19 | }
20 | ],
21 | "start_url": ".",
22 | "display": "standalone",
23 | "theme_color": "#000000",
24 | "background_color": "#ffffff"
25 | }
26 |
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/public/robots.txt:
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1 | # https://www.robotstxt.org/robotstxt.html
2 | User-agent: *
3 |
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/renovate.json:
--------------------------------------------------------------------------------
1 | {
2 | "extends": [
3 | "config:base"
4 | ],
5 | "automerge": true,
6 | "major": {
7 | "automerge": false
8 | },
9 | "labels": [
10 | "type: dependencies",
11 | "renovate"
12 | ],
13 | "masterIssue": true,
14 | "timezone": "America/New_York",
15 | "schedule": [
16 | "every weekend"
17 | ],
18 | "packageRules": [
19 | {
20 | "packagePatterns": ["*"],
21 | "excludePackagePatterns": [
22 | "cypress",
23 | "@cypress/code-coverage",
24 | "@cypress/instrument-cra",
25 | "start-server-and-test"
26 | ],
27 | "enabled": false
28 | }
29 | ]
30 | }
31 |
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/src/App.css:
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1 | .App {
2 | text-align: center;
3 | }
4 |
5 | .App-logo {
6 | height: 40vmin;
7 | pointer-events: none;
8 | }
9 |
10 | @media (prefers-reduced-motion: no-preference) {
11 | .App-logo {
12 | animation: App-logo-spin infinite 20s linear;
13 | }
14 | }
15 |
16 | .App-header {
17 | background-color: #282c34;
18 | min-height: 100vh;
19 | display: flex;
20 | flex-direction: column;
21 | align-items: center;
22 | justify-content: center;
23 | font-size: calc(10px + 2vmin);
24 | color: white;
25 | }
26 |
27 | .App-link {
28 | color: #61dafb;
29 | }
30 |
31 | @keyframes App-logo-spin {
32 | from {
33 | transform: rotate(0deg);
34 | }
35 | to {
36 | transform: rotate(360deg);
37 | }
38 | }
39 |
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/src/App.test.tsx:
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1 | import React from 'react';
2 | import { render } from '@testing-library/react';
3 | import App from './App';
4 |
5 | test('renders learn react link', () => {
6 | const { getByText } = render();
7 | const linkElement = getByText(/learn react/i);
8 | expect(linkElement).toBeInTheDocument();
9 | });
10 |
--------------------------------------------------------------------------------
/src/App.tsx:
--------------------------------------------------------------------------------
1 | import React from 'react';
2 | import logo from './logo.svg';
3 | import './App.css';
4 | import {reverse} from './utils'
5 |
6 | const App = () => {
7 | return (
8 |
24 | );
25 | }
26 |
27 | export default App;
28 |
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/src/index.css:
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1 | body {
2 | margin: 0;
3 | font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen',
4 | 'Ubuntu', 'Cantarell', 'Fira Sans', 'Droid Sans', 'Helvetica Neue',
5 | sans-serif;
6 | -webkit-font-smoothing: antialiased;
7 | -moz-osx-font-smoothing: grayscale;
8 | }
9 |
10 | code {
11 | font-family: source-code-pro, Menlo, Monaco, Consolas, 'Courier New',
12 | monospace;
13 | }
14 |
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/src/index.tsx:
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1 | import React from 'react';
2 | import ReactDOM from 'react-dom';
3 | import './index.css';
4 | import App from './App';
5 | import * as serviceWorker from './serviceWorker';
6 |
7 | ReactDOM.render(, document.getElementById('root'));
8 |
9 | // If you want your app to work offline and load faster, you can change
10 | // unregister() to register() below. Note this comes with some pitfalls.
11 | // Learn more about service workers: https://bit.ly/CRA-PWA
12 | serviceWorker.unregister();
13 |
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/src/logo.svg:
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1 |
8 |
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/src/react-app-env.d.ts:
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1 | ///
2 |
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/src/serviceWorker.ts:
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1 | // This optional code is used to register a service worker.
2 | // register() is not called by default.
3 |
4 | // This lets the app load faster on subsequent visits in production, and gives
5 | // it offline capabilities. However, it also means that developers (and users)
6 | // will only see deployed updates on subsequent visits to a page, after all the
7 | // existing tabs open on the page have been closed, since previously cached
8 | // resources are updated in the background.
9 |
10 | // To learn more about the benefits of this model and instructions on how to
11 | // opt-in, read https://bit.ly/CRA-PWA
12 |
13 | const isLocalhost = Boolean(
14 | window.location.hostname === 'localhost' ||
15 | // [::1] is the IPv6 localhost address.
16 | window.location.hostname === '[::1]' ||
17 | // 127.0.0.0/8 are considered localhost for IPv4.
18 | window.location.hostname.match(
19 | /^127(?:\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)){3}$/
20 | )
21 | );
22 |
23 | type Config = {
24 | onSuccess?: (registration: ServiceWorkerRegistration) => void;
25 | onUpdate?: (registration: ServiceWorkerRegistration) => void;
26 | };
27 |
28 | export function register(config?: Config) {
29 | if (process.env.NODE_ENV === 'production' && 'serviceWorker' in navigator) {
30 | // The URL constructor is available in all browsers that support SW.
31 | const publicUrl = new URL(
32 | process.env.PUBLIC_URL,
33 | window.location.href
34 | );
35 | if (publicUrl.origin !== window.location.origin) {
36 | // Our service worker won't work if PUBLIC_URL is on a different origin
37 | // from what our page is served on. This might happen if a CDN is used to
38 | // serve assets; see https://github.com/facebook/create-react-app/issues/2374
39 | return;
40 | }
41 |
42 | window.addEventListener('load', () => {
43 | const swUrl = `${process.env.PUBLIC_URL}/service-worker.js`;
44 |
45 | if (isLocalhost) {
46 | // This is running on localhost. Let's check if a service worker still exists or not.
47 | checkValidServiceWorker(swUrl, config);
48 |
49 | // Add some additional logging to localhost, pointing developers to the
50 | // service worker/PWA documentation.
51 | navigator.serviceWorker.ready.then(() => {
52 | console.log(
53 | 'This web app is being served cache-first by a service ' +
54 | 'worker. To learn more, visit https://bit.ly/CRA-PWA'
55 | );
56 | });
57 | } else {
58 | // Is not localhost. Just register service worker
59 | registerValidSW(swUrl, config);
60 | }
61 | });
62 | }
63 | }
64 |
65 | function registerValidSW(swUrl: string, config?: Config) {
66 | navigator.serviceWorker
67 | .register(swUrl)
68 | .then(registration => {
69 | registration.onupdatefound = () => {
70 | const installingWorker = registration.installing;
71 | if (installingWorker == null) {
72 | return;
73 | }
74 | installingWorker.onstatechange = () => {
75 | if (installingWorker.state === 'installed') {
76 | if (navigator.serviceWorker.controller) {
77 | // At this point, the updated precached content has been fetched,
78 | // but the previous service worker will still serve the older
79 | // content until all client tabs are closed.
80 | console.log(
81 | 'New content is available and will be used when all ' +
82 | 'tabs for this page are closed. See https://bit.ly/CRA-PWA.'
83 | );
84 |
85 | // Execute callback
86 | if (config && config.onUpdate) {
87 | config.onUpdate(registration);
88 | }
89 | } else {
90 | // At this point, everything has been precached.
91 | // It's the perfect time to display a
92 | // "Content is cached for offline use." message.
93 | console.log('Content is cached for offline use.');
94 |
95 | // Execute callback
96 | if (config && config.onSuccess) {
97 | config.onSuccess(registration);
98 | }
99 | }
100 | }
101 | };
102 | };
103 | })
104 | .catch(error => {
105 | console.error('Error during service worker registration:', error);
106 | });
107 | }
108 |
109 | function checkValidServiceWorker(swUrl: string, config?: Config) {
110 | // Check if the service worker can be found. If it can't reload the page.
111 | fetch(swUrl, {
112 | headers: { 'Service-Worker': 'script' }
113 | })
114 | .then(response => {
115 | // Ensure service worker exists, and that we really are getting a JS file.
116 | const contentType = response.headers.get('content-type');
117 | if (
118 | response.status === 404 ||
119 | (contentType != null && contentType.indexOf('javascript') === -1)
120 | ) {
121 | // No service worker found. Probably a different app. Reload the page.
122 | navigator.serviceWorker.ready.then(registration => {
123 | registration.unregister().then(() => {
124 | window.location.reload();
125 | });
126 | });
127 | } else {
128 | // Service worker found. Proceed as normal.
129 | registerValidSW(swUrl, config);
130 | }
131 | })
132 | .catch(() => {
133 | console.log(
134 | 'No internet connection found. App is running in offline mode.'
135 | );
136 | });
137 | }
138 |
139 | export function unregister() {
140 | if ('serviceWorker' in navigator) {
141 | navigator.serviceWorker.ready.then(registration => {
142 | registration.unregister();
143 | });
144 | }
145 | }
146 |
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/src/setupTests.ts:
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1 | // jest-dom adds custom jest matchers for asserting on DOM nodes.
2 | // allows you to do things like:
3 | // expect(element).toHaveTextContent(/react/i)
4 | // learn more: https://github.com/testing-library/jest-dom
5 | import '@testing-library/jest-dom/extend-expect';
6 |
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/src/utils.tsx:
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1 | export const add = (a:number, b:number) => a + b
2 |
3 | export const reverse = (s:string|null) => {
4 | if (s === null) {
5 | return 'null' // this branch will not be called from the app
6 | } else {
7 | return s.split('').reverse().join('')
8 | }
9 | }
10 |
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/tsconfig.json:
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1 | {
2 | "compilerOptions": {
3 | "target": "es5",
4 | "lib": [
5 | "dom",
6 | "dom.iterable",
7 | "esnext"
8 | ],
9 | "allowJs": true,
10 | "skipLibCheck": true,
11 | "esModuleInterop": true,
12 | "allowSyntheticDefaultImports": true,
13 | "strict": true,
14 | "forceConsistentCasingInFileNames": true,
15 | "module": "esnext",
16 | "moduleResolution": "node",
17 | "resolveJsonModule": true,
18 | "isolatedModules": true,
19 | "noEmit": true,
20 | "jsx": "react"
21 | },
22 | "include": [
23 | "src"
24 | ]
25 | }
26 |
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