[BUG] Unknown file extension ".ts" on fresh init when adding `"type": "module"`

Context:

• Playwright Version: 1.27.1
• Operating System: Mac
• Node.js version: 16.5.0
• Browser: N/A
• Extra: N/A

System:

• OS: macOS 12.6
• Memory: 89.59 MB / 16.00 GB

Binaries:

• Node: 16.5.0 - ~/.nvm/versions/node/v16.5.0/bin/node
• npm: 8.3.0 - ~/.nvm/versions/node/v16.5.0/bin/npm

Languages:

• Bash: 3.2.57 - /bin/bash

Code Snippet

N/A

Describe the bug

In a completely empty directory I ran npm init playwright@latest, and chose

✔ Do you want to use TypeScript or JavaScript? · TypeScript
✔ Where to put your end-to-end tests? · tests
✔ Add a GitHub Actions workflow? (y/N) · false
✔ Install Playwright browsers (can be done manually via 'npx playwright install')? (Y/n) · false

Then I ran npx playwright test and everything ran correctly. Then I added "type": "module" to my package.json and ran npx playwright test again.

Received this error

TypeError: Unknown file extension ".ts" for /Users/my-name/Development/playwright-ts-bug/playwright.config.ts

[acdcjunior]

I got this error in a monorepo where the package with TS tests had "type": "module", and playwright was installed in the root.

Setting "type": "module", in the root as well fixed the problem.

I don’t have non "type": "module", packages, so take it with a grain of salt.

[pleek91]

Okay, I’ll update node and try that again when I have a chance. Thank you! I’ll close this issue.