Puppeteer から Playwright への移行

Compatibility

The Playwright team says most Puppeteer APIs can be used as they are, and the guide covers moving to both the Playwright Library and Playwright Test. Beyond Chromium, Playwright also drives Firefox and WebKit, which Puppeteer does not support.

Before you switch

1. Import the browser explicitly: const { chromium } = require('playwright'), then chromium.launch(). firefox and webkit work the same way.
2. Replace browser.createIncognitoBrowserContext(...) with browser.newContext(...), and use browser contexts for state isolation.
3. Rename the calls the cheat sheet lists: page.setViewport becomes page.setViewportSize, page.waitForNetworkIdle(...) becomes page.waitForLoadState('networkidle'), and waitUntil: 'networkidle2' becomes waitUntil: 'networkidle'.
4. Move element actions onto locators: page.click(selector) becomes page.locator(selector).click(), and likewise for focus, hover and tap. page.select becomes selectOption, page.type becomes fill, and file uploads through elementHandle.uploadFile(...) become setInputFiles(...).
5. Cookies move from the page to the context: browserContext.cookies, browserContext.addCookies and browserContext.clearCookies.
6. For tests, the guide recommends Playwright Test over Jest plus Puppeteer. Import test and expect from @playwright/test, take page from the test’s parameters, and replace page.$eval() checks with web-first assertions such as expect(locator).toContainText(...).

Pitfalls

• Locators are strict. Any action on a locator that targets a DOM element throws if more than one element matches the selector.
• ElementHandle is discouraged. page.$(...) and page.$x(...) have no direct replacement in the cheat sheet: the guide points at locators instead.
• The cheat sheet maps page.deleteCookie(...cookies) to browserContext.clearCookies(), so check deletions of specific cookies against the Playwright API reference.
• Playwright Test creates an isolated Page for each test. To share one page across tests, create it in test.beforeAll() and close it in test.afterAll().
• page.waitForNavigation and page.waitForSelector still exist, but auto-waiting makes them unnecessary in many cases, and the guide says networkidle is rarely useful for the same reason.
• To intercept and change requests, use page.route().