Merge pull request #209 from blockscout/playwright-setup

playwright setup and git lfs

.gitattributes

+__snapshots__/** filter=lfs diff=lfs merge=lfs -text

.github/workflows/playwright.yml

+name: playwright
+on: [pull_request]
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    container:
+      image: mcr.microsoft.com/playwright:v1.27.0-focal
+
+    steps:
+      - run: apt-get update && apt-get install git-lfs
+      - uses: actions/checkout@v3
+        with:
+          lfs: 'true'
+      - uses: actions/setup-node@v2
+        with:
+          node-version: '16'
+      - name: Install dependencies
+        run: yarn
+      - name: Run your tests
+        run: HOME=/root yarn test-ct
+      - name: Upload test results
+        if: always()
+        uses: actions/upload-artifact@v2
+        with:
+          name: playwright-report
+          path: playwright-report
\ No newline at end of file

.gitignore

@@ -39,3 +39,6 @@ yarn-error.log*
 
 # Sentry
 .sentryclirc
+/test-results/
+/playwright-report/
+/playwright/.cache/

.husky/post-checkout

+#!/bin/sh
+command -v git-lfs >/dev/null 2>&1 || { echo >&2 "\nThis repository is configured for Git LFS but 'git-lfs' was not found on your path. If you no longer wish to use Git LFS, remove this hook by deleting '.git/hooks/post-checkout'.\n"; exit 2; }
+git lfs post-checkout "$@"

.husky/post-commit

+#!/bin/sh
+command -v git-lfs >/dev/null 2>&1 || { echo >&2 "\nThis repository is configured for Git LFS but 'git-lfs' was not found on your path. If you no longer wish to use Git LFS, remove this hook by deleting '.git/hooks/post-commit'.\n"; exit 2; }
+git lfs post-commit "$@"

.husky/post-merge

+#!/bin/sh
+command -v git-lfs >/dev/null 2>&1 || { echo >&2 "\nThis repository is configured for Git LFS but 'git-lfs' was not found on your path. If you no longer wish to use Git LFS, remove this hook by deleting '.git/hooks/post-merge'.\n"; exit 2; }
+git lfs post-merge "$@"

.husky/pre-push

+#!/bin/sh
+command -v git-lfs >/dev/null 2>&1 || { echo >&2 "\nThis repository is configured for Git LFS but 'git-lfs' was not found on your path. If you no longer wish to use Git LFS, remove this hook by deleting '.git/hooks/pre-push'.\n"; exit 2; }
+git lfs pre-push "$@"

README.md

@@ -9,6 +9,7 @@ Core technologies what used in the project are
 - [Next.js](https://nextjs.org/) as application framework
 - [Chakra](https://chakra-ui.com/) as component library; our theme customization could be found in `/theme` folder
 - [css-modules](https://github.com/css-modules/css-modules) as lib for styling custom components
+- [playwright](https://playwright.dev/) as a tool for components visual testing
 
 And of course our premier language is [Typescript](https://www.typescriptlang.org/)
 
@@ -21,6 +22,11 @@ For local development please follow next steps:
 - create local env file `.env.local` according to `.env.example` snapshot (see list of used environment variables [below](#environment-variables))
 - run `yarn dev` to spin up local dev server and navigate to the host from logs output
 
+## Components visual testing
+
+We use [playwright experimental components testing](https://playwright.dev/docs/test-components) for visual (screenshots) CI check. Test renders a single component in headless browser in docker, generates screenshots and then compares this screenshot with a reference one.
+To perform testing locally you need to install docker and run `yarn test-docker`
+
 ## Environment variables
 ### Variables list
 The app instance could be customized by passing following variables to NodeJS environment.

package.json

@@ -13,7 +13,9 @@
     "start": "next start",
     "lint:eslint": "./node_modules/.bin/eslint . --ext .js,.jsx,.ts,.tsx",
     "prepare": "husky install",
-    "format-svg": "./node_modules/.bin/svgo -r ./icons"
+    "format-svg": "./node_modules/.bin/svgo -r ./icons",
+    "test-ct": "playwright test -c playwright-ct.config.ts",
+    "test-docker": "docker run --rm --network host -v $(pwd):/work/ -w /work/ -it mcr.microsoft.com/playwright:v1.27.0-focal ./run-tests.sh"
   },
   "dependencies": {
     "@chakra-ui/react": "2.3.1",
@@ -42,6 +44,7 @@
     "use-font-face-observer": "^1.2.1"
   },
   "devDependencies": {
+    "@playwright/experimental-ct-react": "^1.26.1",
     "@types/node": "17.0.36",
     "@types/react": "18.0.9",
     "@types/react-dom": "18.0.5",
@@ -53,6 +56,7 @@
     "eslint-plugin-regexp": "^1.7.0",
     "husky": "^8.0.0",
     "lint-staged": ">=10",
+    "playwright": "^1.26.1",
     "svgo": "^2.8.0",
     "typescript": "4.7.2"
   },

playwright-ct.config.ts

+import type { PlaywrightTestConfig } from '@playwright/experimental-ct-react';
+import { devices } from '@playwright/experimental-ct-react';
+
+/**
+ * See https://playwright.dev/docs/test-configuration.
+ */
+const config: PlaywrightTestConfig = {
+  testDir: './',
+
+  testMatch: /.*\.pw\.tsx/,
+
+  /* The base directory, relative to the config file, for snapshot files created with toMatchSnapshot and toHaveScreenshot. */
+  snapshotDir: './__snapshots__',
+
+  /* Maximum time one test can run for. */
+  timeout: 10 * 1000,
+
+  /* Run tests in files in parallel */
+  fullyParallel: true,
+
+  /* Fail the build on CI if you accidentally left test.only in the source code. */
+  forbidOnly: Boolean(process.env.CI),
+
+  /* Retry on CI only */
+  retries: process.env.CI ? 2 : 0,
+
+  /* Opt out of parallel tests on CI. */
+  workers: process.env.CI ? 1 : undefined,
+
+  /* Reporter to use. See https://playwright.dev/docs/test-reporters */
+  reporter: 'html',
+
+  /* Shared settings for all the projects below. See https://playwright.dev/docs/api/class-testoptions. */
+  use: {
+
+    /* Collect trace when retrying the failed test. See https://playwright.dev/docs/trace-viewer */
+    trace: 'on-first-retry',
+
+    /* Port to use for Playwright component endpoint. */
+    ctPort: 3100,
+
+    headless: true,
+  },
+
+  /* Configure projects for major browsers */
+  projects: [
+    {
+      name: 'chromium',
+      use: {
+        ...devices['Desktop Chrome'],
+      },
+    },
+    {
+      name: 'firefox',
+      use: {
+        ...devices['Desktop Firefox'],
+      },
+    },
+    {
+      name: 'webkit',
+      use: {
+        ...devices['Desktop Safari'],
+      },
+    },
+  ],
+};
+
+export default config;

playwright/RenderWithChakra.tsx

+import { ChakraProvider } from '@chakra-ui/react';
+import type { ColorMode } from '@chakra-ui/react';
+import React from 'react';
+
+import theme from '../theme';
+
+type Props = {
+  children: React.ReactNode;
+  colorMode?: ColorMode;
+}
+
+const RenderWithChakra = ({ children, colorMode = 'light' }: Props) => {
+  return (
+    <ChakraProvider theme={{ ...theme, config: { ...theme.config, initialColorMode: colorMode } }}>
+      { children }
+    </ChakraProvider>
+  );
+};
+
+export default RenderWithChakra;

playwright/index.html

+<!DOCTYPE html>
+<html lang="en">
+  <head>
+    <meta charset="UTF-8" />
+    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+    <title>Testing Page</title>
+  </head>
+  <body>
+    <div id="root"></div>
+    <script type="module" src="/playwright/index.ts"></script>
+  </body>
+</html>

playwright/index.ts

+// Import styles, initialize component theme here.
+// import '../src/common.css';
+
+export {};

run-tests.sh

+#!/bin/sh
+yarn install
+yarn test-ct
\ No newline at end of file

ui/shared/Utilization.pw.tsx

+import { test, expect } from '@playwright/experimental-ct-react';
+import React from 'react';
+
+import RenderWithChakra from '../../playwright/RenderWithChakra';
+import Utilization from './Utilization';
+
+test.use({ viewport: { width: 100, height: 50 } });
+
+test('Utilization light', async({ mount }) => {
+  const component = await mount(
+    <RenderWithChakra>
+      <Utilization value={ 0.1 }/>
+    </RenderWithChakra>,
+  );
+  await expect(component).toHaveScreenshot();
+});
+
+test('Utilization dark', async({ mount }) => {
+  const component = await mount(
+    <RenderWithChakra colorMode="dark">
+      <Utilization value={ 0.1 }/>
+    </RenderWithChakra>,
+  );
+  await expect(component).toHaveScreenshot();
+});