Swallowing errors

[mrmlnc]

Swallowing errors

[vjpr]

So looks like it can be reproduced (on my machine) with:

const readdirEnhanced = require('@mrmlnc/readdir-enhanced')
readdirEnhanced.readdirSync('/dev/fd')

Throws:

Error: EBADF: bad file descriptor, lstat '/dev/fd/12'
    at Object.fs.lstatSync (fs.js:941:11)
    at exports.lstat (xxx/node_modules/.registry.npmjs.org/@mrmlnc/readdir-enhanced/2.2.1/node_modules/@mrmlnc/readdir-enhanced/lib/sync/fs.js:59:20)
    at Object.safeCall [as safe] (xxx/node_modules/.registry.npmjs.org/@mrmlnc/readdir-enhanced/2.2.1/node_modules/@mrmlnc/readdir-enhanced/lib/call.js:24:8)
    at stat (xxx/node_modules/.registry.npmjs.org/@mrmlnc/readdir-enhanced/2.2.1/node_modules/@mrmlnc/readdir-enhanced/lib/stat.js:19:8)
    at DirectoryReader.processItem (xxx/node_modules/.registry.npmjs.org/@mrmlnc/readdir-enhanced/2.2.1/node_modules/@mrmlnc/readdir-enhanced/lib/directory-reader.js:178:5)
    at array.forEach.item (xxx/node_modules/.registry.npmjs.org/@mrmlnc/readdir-enhanced/2.2.1/node_modules/@mrmlnc/readdir-enhanced/lib/sync/for-each.js:14:5)
    at Array.forEach (<anonymous>)
    at Object.syncForEach [as forEach] (xxx/node_modules/.registry.npmjs.org/@mrmlnc/readdir-enhanced/2.2.1/node_modules/@mrmlnc/readdir-enhanced/lib/sync/for-each.js:13:9)
    at call.safe (xxx/node_modules/.registry.npmjs.org/@mrmlnc/readdir-enhanced/2.2.1/node_modules/@mrmlnc/readdir-enhanced/lib/directory-reader.js:87:16)
    at onceWrapper (xxx/node_modules/.registry.npmjs.org/@mrmlnc/readdir-enhanced/2.2.1/node_modules/@mrmlnc/readdir-enhanced/lib/call.js:45:17)
    at onceWrapper (xxx/node_modules/.registry.npmjs.org/@mrmlnc/readdir-enhanced/2.2.1/node_modules/@mrmlnc/readdir-enhanced/lib/call.js:45:17)
    at exports.readdir (xxx/node_modules/.registry.npmjs.org/@mrmlnc/readdir-enhanced/2.2.1/node_modules/@mrmlnc/readdir-enhanced/lib/sync/fs.js:19:5)
    at Object.safeCall [as safe] (xxx/node_modules/.registry.npmjs.org/@mrmlnc/readdir-enhanced/2.2.1/node_modules/@mrmlnc/readdir-enhanced/lib/call.js:24:8)
    at DirectoryReader.readNextDirectory (xxx/node_modules/.registry.npmjs.org/@mrmlnc/readdir-enhanced/2.2.1/node_modules/@mrmlnc/readdir-enhanced/lib/directory-reader.js:78:10)
    at Readable.DirectoryReader.stream._read (xxx/node_modules/.registry.npmjs.org/@mrmlnc/readdir-enhanced/2.2.1/node_modules/@mrmlnc/readdir-enhanced/lib/directory-reader.js:57:18)
    at Readable.read (_stream_readable.js:442:10)
    at readdirSync (xxx/node_modules/.registry.npmjs.org/@mrmlnc/readdir-enhanced/2.2.1/node_modules/@mrmlnc/readdir-enhanced/lib/sync/index.js:27:21)
    at Function.readdirSyncStat (xxx/node_modules/.registry.npmjs.org/@mrmlnc/readdir-enhanced/2.2.1/node_modules/@mrmlnc/readdir-enhanced/lib/index.js:34:10)
    at ReaderSync.api (xxx/node_modules/.registry.npmjs.org/fast-glob/2.0.4/node_modules/fast-glob/out/providers/reader-sync.js:25:24)
    at ReaderSync.read (xxx/node_modules/.registry.npmjs.org/fast-glob/2.0.4/node_modules/fast-glob/out/providers/reader-sync.js:35:32)
    at Array.map (<anonymous>)
    at getWorks (xxx/node_modules/.registry.npmjs.org/fast-glob/2.0.4/node_modules/fast-glob/out/index.js:18:18)
    at Function.sync (xxx/node_modules/.registry.npmjs.org/fast-glob/2.0.4/node_modules/fast-glob/out/index.js:24:17)
    at Test.fn (xxx/index.test.js:25:18)
    at Test.callFn (xxx/node_modules/.registry.npmjs.org/ava/0.23.0/node_modules/ava/lib/test.js:305:18)
    at Test.run (xxx/node_modules/.registry.npmjs.org/ava/0.23.0/node_modules/ava/lib/test.js:318:23)
    at runNext (xxx/node_modules/.registry.npmjs.org/ava/0.23.0/node_modules/ava/lib/sequence.js:58:44)
    at Sequence.run (xxx/node_modules/.registry.npmjs.org/ava/0.23.0/node_modules/ava/lib/sequence.js:90:10)
    at Concurrent.run (xxx/node_modules/.registry.npmjs.org/ava/0.23.0/node_modules/ava/lib/concurrent.js:41:37)
    at runNext (xxx/node_modules/.registry.npmjs.org/ava/0.23.0/node_modules/ava/lib/sequence.js:58:44)
    at Sequence.run (xxx/node_modules/.registry.npmjs.org/ava/0.23.0/node_modules/ava/lib/sequence.js:90:10)
    at runNext (xxx/node_modules/.registry.npmjs.org/ava/0.23.0/node_modules/ava/lib/sequence.js:58:44)
    at Sequence.run (xxx/node_modules/.registry.npmjs.org/ava/0.23.0/node_modules/ava/lib/sequence.js:90:10)
    at Bluebird.try (xxx/node_modules/.registry.npmjs.org/ava/0.23.0/node_modules/ava/lib/runner.js:224:48)
    at tryCatcher (xxx/node_modules/.registry.npmjs.org/bluebird/3.5.1/node_modules/bluebird/js/release/util.js:16:23)
    at Function.Promise.attempt.Promise.try (xxx/node_modules/.registry.npmjs.org/bluebird/3.5.1/node_modules/bluebird/js/release/method.js:39:29)
    at Runner.run (xxx/node_modules/.registry.npmjs.org/ava/0.23.0/node_modules/ava/lib/runner.js:224:22)
    at process.on.options (xxx/node_modules/.registry.npmjs.org/ava/0.23.0/node_modules/ava/lib/main.js:84:10)
    at emitOne (events.js:116:13)
    at process.emit (events.js:211:7)
    at process.on.message (xxx/node_modules/.registry.npmjs.org/ava/0.23.0/node_modules/ava/lib/process-adapter.js:14:10)
    at emitTwo (events.js:126:13)
    at process.emit (events.js:214:7)
    at emit (internal/child_process.js:772:12)
    at _combinedTickCallback (internal/process/next_tick.js:141:11)
    at process._tickCallback (internal/process/next_tick.js:180:9) errno: -9, code: 'EBADF', syscall: 'lstat', path: '/dev/fd/12' } }

$ ls -al /dev/fd

dr-xr-xr-x  1 root     wheel         0 15 Feb 15:26 .
dr-xr-xr-x  3 root     wheel      7075 15 Feb 15:26 ..
crw--w----  1 Me       tty     16,  30 17 Feb 11:49 0
crw--w----  1 Me       tty     16,  30 17 Feb 11:49 1
crw--w----  1 Me       tty     16,  30 17 Feb 11:49 2
dr--r--r--  1 root     wheel         0 15 Feb 15:26 4

This doesn't involve any memfs/unionfs stuff from above.

[vjpr]

Using zsh autocompletion:

~ ls /dev/fd/
0%   1%   10%  11%  12   2%   3

Using ls:

 ~ ls /dev/fd
0 1 2 4

Maybe the additional fd links are creating inside the running process...

https://unix.stackexchange.com/questions/74454/somethings-special-about-dev-fd-3

[mrmlnc]

Hello, @vjpr,

Thanks for reporting! I'll take a look at it very soon.

[mrmlnc]

So, I see that your issue has a two problems (EBADF and code sample). Sorry, but I don't fully understand your problems. Please use GitHub Issue template for clarifying your problem.

EBADF

What is happening?

Why readdirSync works?

Because fs.readdirSync just reads the catalog and doesn't try to read the items inside it.

Why readdir-enhanced works?

Because it works like fs.readdirSync without { deep: true } option. Inside fast-glob we use deep option.

Why glob works?

Because glob first tries to understand what he's dealing with. Related issue that will help to fix this problem:

• #60

Why fast-glob doesn't it work?

Inside fast-glob we use deep: true option and try to look inside the directories. When we try to get lstat or stat it throws error.

Questions

0. What's the expected behavior here?

Code sample

fs.writeFileSync('/app/foo.json', 'foo')
// Results
glob.sync('/app') // ['/app']
fg.sync('/app') // [] Because we don't read entries inside directory (will be fixed by #47)

fs.writeFileSync('/app/foo.json', 'foo')
fs.symlinkSync('/app', '/app/foo')
// Results
glob.sync('/app') // ['/app']
fg.sync('/app') // [] Because we don't read entries inside directory (will be fixed by #47)

glob.sync('./app/**'); // [ 'app', 'app/foo', 'app/foo.json' ]
fg.sync('./app/**', { onlyFiles: false }); // [ 'app/foo', 'app/foo.json' ]

Questions

0. What's the expected behavior here?

[vjpr]

What about:

console.log(glob.sync('/app/foo/*')) // ? ['/app/foo/foo.json']
console.log(fg.sync('/app/foo/*')) // ? []

They should return the same.

[mrmlnc]

Original FS:

const fs = require('fs');

const glob = require('glob');
const fg = require('fast-glob');
const re = require('readdir-enhanced');

fs.mkdirpSync('./app');
fs.writeFileSync('./app/foo.json', 'foo')
fs.symlinkSync('./app', './app/foo')

console.log('fs', fs.readdirSync('./app'));
console.log('glob', glob.sync('./app/*'));
console.log('re', re.sync('./app'));
console.log('fg', fg.sync('./app/*'));

// fs [ 'foo', 'foo.json' ]
// glob [ './app/foo', './app/foo.json' ]
// re [ 'foo', 'foo.json' ]
// fg [ './app/foo.json' ]

VFS:

const fs = require('fs');

const { Volume } = require('memfs');
const { patchFs } = require('fs-monkey');
const { ufs } = require('unionfs');

const glob = require('glob');
const fg = require('fast-glob');
const re = require('readdir-enhanced');

function start() {
    vol = new Volume()
    ufs.use(fs).use(vol);
    patchFs(ufs)
}

start()

vol.mkdirpSync('./app');
vol.writeFileSync('./app/foo.json', 'foo')
vol.symlinkSync('./app', './app/foo')

console.log('fs', vol.readdirSync('./app'));
console.log('glob', glob.sync('./app/*'));
console.log('re', re.sync('./app'));
console.log('fg', fg.sync('./app/*'));

// fs [ 'foo', 'foo.json' ]
// glob [ './app/foo', './app/foo.json' ]
// re [ 'foo', 'foo.json' ]

// Maximum call stack size exceeded
// From `node_modules/unionfs/lib/union.js`

[vjpr]

@streamich Seems like memfs gets stuck in an infinite loop when reading a dir containing a symlink to itself. Original fs as seen above handles this case with no problem.

E.g.

/app
/app/foo -> /app

[mrmlnc]

I'm closing this issue.

The problem with deep reading will be solved in #60.

Feel free to create separate issues for your problems using the GitHub Issue template (env & actual & expected).