Error: Cannot find module

[pOoOf]

Node version (or tell us if you're using electron or some other framework):

v8.10.0

ShellJS version (the most recent version/Github branch you see the bug on):

0.8.3

Operating system:

Ubuntu

Description of the bug:

I am using shelljs to execute git commands in the jenkins build server and it works fine most of the time, shelljs is breaking randomly and i am not sure what is causing this error, here is the stack trace

Error: Cannot find module '/home/jenkins/.nvm/versions/node/v8.10.0/lib/node_modules/changelog/node_modules/shelljs/src/exec-child.js'
    at Function.Module._resolveFilename (module.js:547:15)
    at Function.Module._load (module.js:474:25)
    at Function.Module.runMain (module.js:693:10)
    at startup (bootstrap_node.js:188:16)
    at bootstrap_node.js:609:3
/home/jenkins/.nvm/versions/node/v8.10.0/lib/node_modules/changelog/node_modules/shelljs/src/common.js:399
        throw e;
        ^

ShellJSInternalError: ENOENT: no such file or directory, open '/tmp/shelljs_b8257e7bea931a3aa31d'
    at Object.fs.openSync (fs.js:646:18)
    at Object.fs.readFileSync (fs.js:551:33)
    at execSync (/home/jenkins/.nvm/versions/node/v8.10.0/lib/node_modules/changelog/node_modules/shelljs/src/exec.js:89:17)
    at Object._exec (/home/jenkins/.nvm/versions/node/v8.10.0/lib/node_modules/changelog/node_modules/shelljs/src/exec.js:205:12)
    at Object.exec (/home/jenkins/.nvm/versions/node/v8.10.0/lib/node_modules/changelog/node_modules/shelljs/src/common.js:335:23)
    at Object.getTags (/home/jenkins/.nvm/versions/node/v8.10.0/lib/node_modules/changelog/lib/gitUtils.js:58:20)
    at Pipeline.process (/home/jenkins/.nvm/versions/node/v8.10.0/lib/node_modules/changelog/lib/pipeline.js:62:23)
    at Object.<anonymous> (/home/jenkins/.nvm/versions/node/v8.10.0/lib/node_modules/changelog/bin/changelog.js:40:20)
    at Module._compile (module.js:652:30)
    at Object.Module._extensions..js (module.js:663:10)

Example ShellJS command to reproduce the error:

shell.exec(git tag -l --sort=-v:refname, {async:false, silent: !this.logging});

[nfischer]

There's something seriously wrong if shell.exec() can't find exec-child.js. This is one of the files in our module, so it should definitely be on the file system. This sounds like a package manager bug to me, or something else is deleting the file out from under you.

[pOoOf]

and what does this line means

ShellJSInternalError: ENOENT: no such file or directory, open '/tmp/shelljs_b8257e7bea931a3aa31d'

Is there is anything from my side that i can try

[nfischer]

I think that's one of the temp files we use to plumb stdio to/from the child process. I think, when we can't find the child-exec.js module, we try to throw an exception using the stderr value for the message. But there might be no stderr if child-exec.js never runs, so we're hitting a double error.

I think the main issue is still that we can't find child-exec.js though, and I don't think the "double error" is itself an issue, since it's reasonable to expect all our files to be there.

Is this something you can repro locally? I'm worried the flakiness will make this hard to investigate (I've never seen the issue locally or on our own CI).

[pOoOf]

Okay thanks, since this is happening quite randomly on cicd server, will try to reproduce this locally and if happens, will update it here.