Error in jest watch when using yarn for dependency installation

If you are reporting a bug, please fill in below. Otherwise feel free to remove this template entirely.

Can you reproduce the problem with latest npm?

Can you still reproduce it?

Yes.

Description

npm test, yarnpkg test, yarn test all fail when dependencies are installed with yarn install. They all work fine when dependencies are installed with npm install.

In CI mode (not watched), tests run fine after installing deps with yarn. Research indicates others are having similar problems with tools like Watchman which leads me to believe that something is different in how Jest is performing the watch depending on how it is installed. There is also a sense that this has to do with OSX Sierra.

Expected behavior

Tests run

Actual behavior

Crash. See stack trace beow.

Environment

Run these commands in the project folder and fill in their results:

1. npm ls react-scripts: react-scripts@0.8.5
2. node -v: v7.4.0
3. npm -v: 4.1.2

Then, specify:

1. Operating system: Darwin trefoil 16.3.0 Darwin Kernel Version 16.3.0: Thu Nov 17 20:23:58 PST 2016; root:xnu-3789.31.2~1/RELEASE_X86_64 x86_64

2. Browser and version: Not a browser isssue

Reproducible Demo

Easy: this happens from a fresh create-react-app when Yarn (freshly brewed today) is installed. yarnpkg test will fail. Now delete node_modules and run npm install now npm test works fine. delete node_modues and run yarn install, bad behavior returns.

Push to GitHub and paste the link here.

https://github.com/aztecrex/demo-create-react-app-yarn-problem

Full stack trace:

2017-01-30 18:58 node[77220] (FSEvents.framework) FSEventStreamStart: register_with_server: ERROR: f2d_register_rpc() => (null) (-22)
2017-01-30 18:58 node[77220] (FSEvents.framework) FSEventStreamStart: register_with_server: ERROR: f2d_register_rpc() => (null) (-22)
2017-01-30 18:58 node[77220] (FSEvents.framework) FSEventStreamStart: register_with_server: ERROR: f2d_register_rpc() => (null) (-22)
2017-01-30 18:58 node[77220] (FSEvents.framework) FSEventStreamStart: register_with_server: ERROR: f2d_register_rpc() => (null) (-22)
2017-01-30 18:58 node[77220] (FSEvents.framework) FSEventStreamStart: register_with_server: ERROR: f2d_register_rpc() => (null) (-22)
2017-01-30 18:58 node[77220] (FSEvents.framework) FSEventStreamStart: register_with_server: ERROR: f2d_register_rpc() => (null) (-22)
2017-01-30 18:58 node[77220] (FSEvents.framework) FSEventStreamStart: register_with_server: ERROR: f2d_register_rpc() => (null) (-22)
2017-01-30 18:58 node[77220] (FSEvents.framework) FSEventStreamStart: register_with_server: ERROR: f2d_register_rpc() => (null) (-22)
2017-01-30 18:58 node[77220] (FSEvents.framework) FSEventStreamStart: register_with_server: ERROR: f2d_register_rpc() => (null) (-22)
events.js:160
      throw er; // Unhandled 'error' event
      ^

Error: Error watching file for changes: EMFILE
    at exports._errnoException (util.js:1022:11)
    at FSEvent.FSWatcher._handle.onchange (fs.js:1283:11)
error Command failed with exit code 1.

[tsironis]

I fixed the issue upgrading yarn to v0.20.1 and then brew install watchman. Apparently, there is a problem watching file changes in macOS Sierra.

[aztecrex]

Removed those dirs and the “install watchman” workaround fixes the problem. Uninstalling watchman causes it to re-occur.

@hongrich glad I tried it again