[REGRESSION]: Tests not detected as ES module in v1.20

[henrikstorck]

Context:

• GOOD Playwright Version: 1.19.2
• BAD Playwright Version: 1.20.0
• Operating System: Windows

Code Snippet

https://github.com/henrikstorck/playwright-test

Describe the bug

When running npm test in the above repository, I get the following error message with playwright v1.20:

> npm test

Running 0 test using 0 worker


Error [ERR_REQUIRE_ESM]: require() of ES Module D:\Projects\playwright-test\tests\test.js from D:\Projects\playwright-test\node_modules\@playwright\test\lib\loader.js not supported.
Instead change the require of test.js in D:\Projects\playwright-test\node_modules\@playwright\test\lib\loader.js to a dynamic import() which is available in all CommonJS modules.

   at node_modules\@playwright\test\lib\loader.js:244

  242 |
  243 |       if (isModule) return await esmImport();
> 244 |       return require(file);
      |              ^
  245 |     } catch (error) {
  246 |       if (error.code === 'ERR_MODULE_NOT_FOUND' && error.message.includes('Did you mean to import')) {
  247 |         var _$exec;

    at Loader._requireOrImport (D:\Projects\playwright-test\node_modules\@playwright\test\lib\loader.js:244:14)
    at Loader.loadTestFile (D:\Projects\playwright-test\node_modules\@playwright\test\lib\loader.js:142:18)
    at Runner._runFiles (D:\Projects\playwright-test\node_modules\@playwright\test\lib\runner.js:295:44)
    at Runner._run (D:\Projects\playwright-test\node_modules\@playwright\test\lib\runner.js:231:23)
    at async TimeoutRunner.run (D:\Projects\playwright-test\node_modules\playwright-core\lib\utils\async.js:38:14)
    at async raceAgainstTimeout (D:\Projects\playwright-test\node_modules\playwright-core\lib\utils\async.js:85:15)
    at async Runner.runAllTests (D:\Projects\playwright-test\node_modules\@playwright\test\lib\runner.js:188:20)
    at async runTests (D:\Projects\playwright-test\node_modules\@playwright\test\lib\cli.js:184:18)
    at async Command.<anonymous> (D:\Projects\playwright-test\node_modules\@playwright\test\lib\cli.js:79:7)

=================
 no tests found.
=================

Since updating to playwright v1.20, playwright appears to no longer detect tests in nested directories as part of ES modules, which causes the test execution to fail because playwright loads the tests with require() instead of import.

When downgrading to v1.19, the test gets detected and executed successfully as expected.

I'm assuming that folderIsModule is broken in v1.20. (possibly caused by #12292)
When debugging the function, it appears as if it is not able to iterate through the parent directories. Because of that it can't find the package.json with the "type": "module" and therefore doesn't detect if the file is part of an ES module.

If my assumption is right, changing path.basename in the folderIsModule function to path.dirname should allow folderIsModule to correctly iterate through it's parent directories and find the package.json.

Reproducable on local Windows machine and ubuntu runner for github action.

[pavelfeldman]

Fixed, pending 1.20.1 update.

[mroderick]

If you can't wait for the release, you can use the beta tag when installing the package :)

[frederikhors]

Something is broken with 1.20.1 from 1.20.0 I think because of this on Windows.

I don't have time now to fill the regression report, but playwright doesn't start with 1.20.1 for ERR_MODULE_NOT_FOUND error.