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Profiling a Test with Playwright's Trace Viewer

Playwright's Trace Viewer is a powerful tool that allows you to profile your tests. It provides a detailed view of each action, including the state of the page before and after the action. You can inspect the log, source, and network during each step of the test.

Running Your Tests

First, you need to run your tests. Use the command npx playwright show-report to do this.

npx playwright show-report

Opening the Trace Viewer

After running your tests, an HTML report will open in your browser. You'll see a trace icon next to the test name file name. Click on this icon to open the Trace Viewer for that specific test.

Alternatively, you can open the detailed view of a specific test, scroll down to the 'Traces' tab, and click on the trace screenshot to view it.

Analyzing Your Test

Inside the Trace Viewer, you'll see all actions performed by Playwright along with their respective timings. This information is invaluable when you're trying to identify bottlenecks or slow running tests.

Remember, the Trace Viewer creates a DOM snapshot, so you can fully interact with it, open devtools, and more.

Happy testing with Playwright! For more tips and tricks, check out our blog post on Mastering Playwright Test Automation.