Bug: Watch mode on Linux causes a ENOSPC Node.js error

[maraisr]

Versions:

• Yarn: v0.21.3
• Node: v6.9.2
• npm: 3.10.9
• Ubuntu: 16.10

Installed using: yarn global add jest (With a chown at ~/.config/yarn/global/node_modules/)

Command failed: jest -c lib/tools/testing/jest.config.json --no-cache --watch

If I run jest -c lib/tools/testing/jest.config.json --no-cache testing works 100% fine.

Error message:

fs.js:1431
    throw error;
    ^

Error: watch /home/fooBar/dev/blah/lib/tools/testing/node_modules/core-js/modules ENOSPC
    at exports._errnoException (util.js:1022:11)
    at FSWatcher.start (fs.js:1429:19)
    at Object.fs.watch (fs.js:1456:11)
    at NodeWatcher.watchdir (/home/fooBar/.config/yarn/global/node_modules/sane/src/node_watcher.js:148:20)
    at Walker.<anonymous> (/home/fooBar/.config/yarn/global/node_modules/sane/src/node_watcher.js:361:12)
    at emitTwo (events.js:106:13)
    at Walker.emit (events.js:191:7)
    at /home/fooBar/.config/yarn/global/node_modules/walker/lib/walker.js:69:16
    at go$readdir$cb (/home/fooBar/.config/yarn/global/node_modules/graceful-fs/graceful-fs.js:149:14)
    at FSReqWrap.oncomplete (fs.js:123:15)

Tmp dir: yarn config set tmp /tmp/

Disk free space: df -h / (11% used)

Jest config: at lib/tools/testing/jest.config.json

{
	"clearMocks": true,
	"bail": true,
	"transform": {
		".(ts|tsx)": "<rootDir>/lib/tools/testing/node_modules/ts-jest/preprocessor.js"
	},
	"testResultsProcessor": "<rootDir>/lib/tools/testing/node_modules/ts-jest/coverageprocessor.js",
	"testMatch": [
		"**/__tests__/*.(ts|tsx|js)"
	],
	"moduleFileExtensions": [
		"ts",
		"tsx",
		"js"
	],
	"moduleDirectories": [
		"node_modules",
		"<rootDir>/lib/tools/testing/node_modules"
	],
	"collectCoverage": true,
	"coverageDirectory": "./reports/",
	"coverageReporters": [
		"clover",
		"lcov",
		"text-summary"
	],
	"coverageThreshold": {
		"global": {
			"branches": 50,
			"functions": 80,
			"lines": 60
		}
	},
	"collectCoverageFrom": [
		"{src,lib}/**/*.{ts,js}",
		"!lib/{tools}/**/*",
		"!**/{node_modules,vendor}/**"
	]
}

[cpojer]

This means there is no space on your drive. Please cleanup your disk.

[maraisr]

@cpojer not sure if you read the issue, but;

Disk free space: df -h / (11% used)

was mentioned in there - disk space although reported as the issue, is actually not the issue.

[maraisr]

Bump @cpojer

[zackabrah]

I am having the same issue, and there's definitely free disk space

[cpojer]

Unfortunately we do not have resources to debug this on Linux. If you have time and you could take a look and help us with a pull request to fix it, that would be greatly appreciated.

[maraisr]

@cpojer I'll take a look - but I also believe it is not limited to the Linux OS. Regardless, do you mind re-opening this issue?

[maraisr]

From my findings its not related to Jest at all. On Linux (or Mac) we have a max number of system watchers we can place at an IO level (from my understanding). So for large projects, it seems that Jest is trying to watch just way to many files.

To fix:

echo fs.inotify.max_user_watches=524288 | sudo tee -a /etc/sysctl.conf && sudo sysctl -p

Source: Node.JS Error: ENOSPC

[cpojer]

Thanks for investigating, if you install watchman, it should work.

[samit4me]

Just recently switched from Windows 7 to Ubuntu 16.04.2 LTS and Jest was working great in Windows but failed to run under Linux for the same reasons listed above. It only seems to fail if you add the --watch flag.

Firstly I took @cpojer advice and installed watchmen as per docs and ran the jest --watch again and I got the following errors:

jest --watch

events.js:163
      throw er; // Unhandled 'error' event
      ^

Error: A non-recoverable condition has triggered.  Watchman needs your help!
The triggering condition was at timestamp=1493335106: inotify-add-watch(/home/username/project_name/node_modules/browser-resolve/node_modules/resolve/example) -> The user limit on the total number of inotify watches was reached; increase the fs.inotify.max_user_watches sysctl
All requests will continue to fail with this message until you resolve
the underlying problem.  You will find more information on fixing this at
https://facebook.github.io/watchman/docs/troubleshooting.html#poison-inotify-add-watch

    at ChildProcess.<anonymous> (/home/username/project_name/node_modules/sane/node_modules/fb-watchman/index.js:207:21)
    at emitTwo (events.js:106:13)
    at ChildProcess.emit (events.js:194:7)
    at maybeClose (internal/child_process.js:899:16)
    at Socket.<anonymous> (internal/child_process.js:342:11)
    at emitOne (events.js:96:13)
    at Socket.emit (events.js:191:7)
    at Pipe._handle.close [as _onclose] (net.js:510:12)
npm ERR! Test failed.  See above for more details.

This was useful as it tells you what to do, so I then used the fix from @maraisr and jest is now working on Ubuntu 🎉 🍻

echo fs.inotify.max_user_watches=524288 | sudo tee -a /etc/sysctl.conf && sudo sysctl -p

Thank you for figuring this out @maraisr @cpojer 👍 Do you think something should be added to the Jest website?

[samseralam]

Thanks Bro @maraisr