fix(initialize-node): __dirname in some envrioments

[codydaig]

This patch fixes __dirname pointing to / in some envrioments by
trying process.cwd() if __dirname returne undefined.

Issues: #7085 #7932

What kind of change does this PR introduce?

Fixes #7932 where certain node environments with webpack don't place nicely to __dirname.

Did you add tests for your changes?

No. This is very difficult to reproduce in simple environments. This change only affects those where __dirname returns undefined on initialization.

If relevant, did you update the documentation?

No relevant documentation updates needed.

Summary

When __dirname points to / it falls back to process.cwd to get the projectRoot on initialization.

Does this PR introduce a breaking change?

No.

[OrKoN]

@jackfranklin could you please take a look?

[OrKoN]

Why does it work with process.cwd()? I assume that the cwd is not the Puppeteer's installation folder in node_modules, is it? In those environments, do you still rely on Puppeteer to download the browser binary?

[OrKoN]

Does it work if you specify the path via PUPPETEER_DOWNLOAD_PATH or skip download PUPPETEER_SKIP_CHROMIUM_DOWNLOAD?

[codydaig]

I don't think you can just rely on PUPPETEER_DOWNLOAD_PATH because it's starting out by setting puppeteerRootDirectory to undefined (if __dirname is root) and that errors when creating a new BrowserFetcher passing in the project root (Launcher.ts line 808). I could be mistaken and can double check this later today.

You are correct that process.cwd() doesn't return the puppeteer root Directory, but the directory in which they are in, but regardless, i believe they end up resolving the same after pkgDir.sync() finding the project root.

I know with this, it was able to find the chromium install inside the node_modules folder. I can double check the Download path env variable in a bit and see if that resolves it.

[OrKoN]

codydaig@ actually, have you tried to re-configure webpack to have the proper __dirname? https://codeburst.io/use-webpack-with-dirname-correctly-4cad3b265a92 I am a bit hesitant to merge the CL as is as it'd be installing chromium into the cwd instead of the node_modules/puppeteer folder. It'd be great if you could share a repro as I'd like to get some better understanding of how it works.

[my-lalex]

Why not use the require.resolve Node API to get the puppeteer package location?

[OrKoN]

Opened a PR to use require.resolve #8003 Also, verified that it works in a webpack bundled Puppeteer version.

[OrKoN]

That has now landed. I think it should work better than __dirname in Webpack environments. Let me know if it's not the case.

[codydaig]

Thanks! Confirmed that it's fixed. (sorry for the delay, family stuff got in the way).