Testing with Jest failed with Error: Error watching file for changes: EMFILE

Question

I tried to write a test for a React.js app. Everything was going fine but after making the directory tracked with Git(made a Git repo with it). The test fails with the error below

2017-01-15 05:05 node[1278] (FSEvents.framework) FSEventStreamStart: register_with_server: ERROR: f2d_register_rpc() => (null) (-22)
2017-01-15 05:05 node[1278] (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:1406:11)

I am sure that this is because of .git directory because when I remove .git directory it is running without the error. It seems that the exception occurs in watching the files. My development environment is MacOS 10.12.2 and Node 6.9.4. How can I resolve this issue?

Answer 1

Oh, I am going to answer my question after hours of my struggling.
The best solution is to install the latest version of Watchman.
The old version of Watchman causes fsevents module throws the exception.

After installing watchman, optionally you can run sudo chown -R $(whoami):staff ~/Library/LaunchAgents to give the permission.

Answer 2

I have ran into the same problem and upgrade watchman didn't fix this for me. Reading the documentation of Jest, you will find there is an option to disable using watchman. So I guess watchman is not necessary.

What fixed this for me is to upgrade Jest to the lastest version using npm install --save-dev jest@latest.