Watchman crawl failed.

[vjeux]

I'm running into this error on master with a project created with npm run create-react-app ../test

jest-haste-map: Watchman crawl failed. Retrying once with node crawler.
Error: Watchman error: resolve_projpath: none of the files listed in global config root_files are present in path /Users/vjeux/random/test or any of its parent directories. Make sure watchman is running for this project. See https://facebook.github.io/watchman/docs/troubleshooting.html.

I came up with the "Painless unit testing" sentence. It's now a reality :)

[gaearon]

None of these words make any sense to our users: jest-haste-map watchman crawl node crawler resolve_projpath config root_files. They shouldn’t be in our messages.

If we recommend installing Watchman we should explain why and what it gives you (faster watching)? The message should not include any references to configs and jargon.

[gaearon]

Also the warning links to https://facebook.github.io/watchman/docs/troubleshooting.html which says nothing about how to install Watchman.

https://facebook.github.io/watchman/docs/install.html suggests to use brew or macports which is not at all beginner-friendly.

I think we need a flag to completely disable this warning/suggestion because it’s optional, and instructions are unfortunately confusing. We can still put instructions on “how to speed up watching” in our Howto.

[vjeux]

cc @cpojer

[gaearon]

@vjeux Did you previously install RN? @cpojer told me this warning only shows up if:

• The folder isn't a Git repo
• You already have Watchman

[vjeux]

I'm a Facebook engineer so watchman is installed on my machine by default ;)

[gaearon]

Ah that explains it. 😄

[cpojer]

I confirmed that this error is only thrown when using Facebook equipment so I think this isn't actionable and we can close it. I expect FB engineers to figure out how to use watchman, however we might want to improve the error message in Jest to make sure people understand it is no reason to panic.

how to repro a non fb-environment:
create ~/watchman and put {} into the file then run:
watchman shutdown-server; WATCHMAN_CONFIG_FILE=~/watchman watchman --foreground --logfile=/dev/stdout --no-save-state --statefile=/dev/null

then run jest --no-cache and you shouldn't see the error.

[gaearon]

Thanks for checking.

[pjm17971]

For what it's worth, I got this error as well, so it can happen on non-fb equipment. It was because I'd tried jest in the past and ended up with watchman installed on my machine. At least I think that's how I ended up with it. Uninstalling it made the error go away. It would be nice to not ever show this message though. It was cryptic.