playwright: [BUG] Can't use component testing in existing project

Context:

• Playwright Version: 1.26.1
• Operating System: Mac
• Node.js version: 16.13.0
• Browser: All

CodeSandbox link showing bug (running below repo): https://github.com/piotrpalek/playwright-issue Github link to example repo: https://github.com/piotrpalek/template-hcp/tree/playwright

The error

Error: Cannot find module '/project/template-hcp/spec/javascripts/utils/apiMock' imported from /project/template-hcp/src/App.pw.tsx

Describe the bug

Hey, I’m trying to run playwright, on an existing webpack project, but I’m getting an issue when trying to import modules without adding a file extension. It’s saying “Error: Cannot find module” when trying to run it. I’ve succeeded in making an example repo showing the exact same issue.

It would be pretty cumbersome (and against our current styleguide) to change all imports to have file extensions. Is there a workaround I could use here?

Extra

After some initial debugging I’ve found that at this point (filename.endsWith...), playwright throws an error, it’s just getting swallowed along the way. The error that it’s throwing is:

'Cannot read properties of null (reading 'endsWith')'