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child_process.exec tries to launch node (instead of shell command) in some odd circumstances

I am trying to run some simple commands using child_process.exec. But in some odd corner cases, it tries to execute the given command with node, rather than the given (or default) shell.
Results
E.g., given below code, I get the following results:
cmd
Result
❌
'"yarn" -v'
Cannot find module 'C:\cwd\yarn.js'
❌
'"npm" -v'
Cannot find module 'C:\cwd\node_modules\npm\bin\npm-cli.js'
✅
'yarn -v'
(works as expected)
✅
'"C:\path\to\yarn" -v'
(works as expected)
OS: Win10
Node: v16., v17. (tried several of them)
EDIT: This seems to be a cmd-specific problem. If I set processOptions.shell = 'bash', it does not occur.
Full Error Message
node:internal/modules/cjs/loader:936
throw err;
^
Error: Cannot find module 'C:\cwd\yarn.js'
at Function.Module._resolveFilename (node:internal/modules/cjs/loader:933:15)
at Function.Module._load (node:internal/modules/cjs/loader:778:27)
at Function.executeUserEntryPoint [as runMain] (node:internal/modules/run_main:81:12)
at node:internal/main/run_main_module:17:47 {
code: 'MODULE_NOT_FOUND',
requireStack: []
}
Done - code 1 signal null
Thoughts
It appears that there is a special logic that is triggered, iff the "executable" is in double quotes, and has no spaces or path separators in them...?
Not sure if feature or bug?
Code
// test.js
const cp = require('child_process');
const cmd = '"yarn" install';
const child = cp.exec(cmd);
// ###########################################################################
// process monitoring
// ###########################################################################
child.on('exit', (code, signal) => {
console.log('Done - code', code, ' signal', signal);
});
child.on('error', (err) => {
console.error(`Error:`, err);
});
// inherit stdio
child.stdout.pipe(process.stdout);
process.stdin.pipe(child.stdin);
child.stderr.pipe(process.stderr);

Turns out, it is a volta bug. I filed it here.
Easy to verify: Change the command to do other things on top of "yarn" install. The following still shows hi, but the yarn part still bugs out, so it is definitely not an issue with node or cmd:
const cmd = 'echo "hi" && "yarn" install';
const child = cp.exec(cmd);
Some more explanation: volta manages node, npm and yarn for you, making it very easy to install/uninstall/pin versions globally or even per folder/project. That means that "yarn" install does not actually run yarn, but actually this:
Runs a volta executable
Which will then run yarn...
...which evidently messed up the logic to look up the actual executable.
This happens only with yarn and npm. Everything else (thus far) seems fine, including node itself.

Truffle '"Migrations" -- cb is not a function'

I wrote a simple smart contract in Solidity 0.6.6 that I'm trying to deploy to the BSC Testnet.
This is what I have in my truffle-config.js file (privateKeys is an array with a single entry of ['0x + privatekey']:
networks: {
bscTestnet: {
provider: () => new HDWalletProvider(
privateKeys,
'https://data-seed-prebsc-1-s1.binance.org:8545/'
),
network_id: 97,
skipDryRun: true
}
}
When I run the command "truffle migrate --reset --network bscTestnet" I get the following error:
Compiling your contracts...
===========================
> Everything is up to date, there is nothing to compile.
Starting migrations...
======================
> Network name: 'bscTestnet'
> Network id: 97
> Block gas limit: 30000000 (0x1c9c380)
1_initial_migration.js
======================
Deploying 'Migrations'
----------------------
Error: *** Deployment Failed ***
"Migrations" -- cb is not a function.
at /Users/admin/.nvm/versions/node/v17.4.0/lib/node_modules/truffle/build/webpack:/packages/deployer/src/deployment.js:365:1
at runMicrotasks (<anonymous>)
at processTicksAndRejections (node:internal/process/task_queues:96:5)
at Migration._deploy (/Users/admin/.nvm/versions/node/v17.4.0/lib/node_modules/truffle/build/webpack:/packages/migrate/Migration.js:70:1)
at Migration._load (/Users/admin/.nvm/versions/node/v17.4.0/lib/node_modules/truffle/build/webpack:/packages/migrate/Migration.js:56:1)
at Migration.run (/Users/admin/.nvm/versions/node/v17.4.0/lib/node_modules/truffle/build/webpack:/packages/migrate/Migration.js:217:1)
at Object.runMigrations (/Users/admin/.nvm/versions/node/v17.4.0/lib/node_modules/truffle/build/webpack:/packages/migrate/index.js:150:1)
at Object.runFrom (/Users/admin/.nvm/versions/node/v17.4.0/lib/node_modules/truffle/build/webpack:/packages/migrate/index.js:110:1)
at Object.runAll (/Users/admin/.nvm/versions/node/v17.4.0/lib/node_modules/truffle/build/webpack:/packages/migrate/index.js:114:1)
at Object.run (/Users/admin/.nvm/versions/node/v17.4.0/lib/node_modules/truffle/build/webpack:/packages/migrate/index.js:79:1)
at runMigrations (/Users/admin/.nvm/versions/node/v17.4.0/lib/node_modules/truffle/build/webpack:/packages/core/lib/commands/migrate/run.js:80:1)
at Object.module.exports [as run] (/Users/admin/.nvm/versions/node/v17.4.0/lib/node_modules/truffle/build/webpack:/packages/core/lib/commands/migrate/run.js:44:1)
at Command.run (/Users/admin/.nvm/versions/node/v17.4.0/lib/node_modules/truffle/build/webpack:/packages/core/lib/command.js:189:1)
Truffle v5.4.31 (core: 5.4.31)
Node v17.4.0

Opened an Issue a about it: https://github.com/trufflesuite/truffle/issues/4676
I guess its a bug in HardwareWallet2.0.2.
Reverting to HardwareWallet2.0.0 solved the problem for me
npm i #truffle/hdwallet-provider#2.0.0

UPDATE:
Right, workaround: I rolled #HDWalletProvider back to v2.0.1 and was able to migrate.
I assume there must be an issue with the new version for ppl who updated today.
================
Same problem with Polygon Mumbai.
Function "cb" refers to the callback function. The strange part is the error message doesn't reference my own code at all; it references the migrations.js located in:
<.nvm/versions/node/v16.11.1/lib/node_modules/truffle/build/webpack:/packages/deployer/src/deployment.js:365:1
at processTicksAndRejections (node:internal/process/task_queues:96:5>
This leads me to believe there's a problem with out 1_initial_migration.js... however that's auto-generated so I can't see any problem... it's strange.
1_initial_migration.js:
const Migrations = artifacts.require("Migrations");
module.exports = function(deployer) {
deployer.deploy(Migrations);
};

Error: spawn node ENOENT

I'm working on my Electron app with Express server and when I build it with electron-packager, I get an error.
Uncaught Exception:
Error: spawn node ENOENT
at exports._errnoException (util.js:1024:11)
at Process.ChildProcess._handle.onexit (internal/child_process.js:192:19)
at onErrorNT (internal/child_process.js:374:16)
at _combinedTickCallback (internal/process/next_tick.js:138:11)
at process._tickCallback (internal/process/next_tick.js:180:9)
at Function.Module.runMain (module.js:607:11)
at startup (bootstrap_node.js:167:16)
at bootstrap_node.js:589:3
here is my main.js where child process is called
const cp = require('child_process');
let instance = cp.spawn('node',['./app.js']);
var electron = require('electron');
var browserWindow = electron.BrowserWindow;
var app = electron.app;
app.on('ready', function(){
// appWindow
var appWindow;
appWindow = new browserWindow({
width:1120,
height:620,
webPreferences: {
plugins: true
},
icon: __dirname + '/public/icon/icon.png'
});
appWindow.loadURL('file://' +__dirname + '/public/prva.html');
//appWindow.webContents.openDevTools();
});
// close app after all windows are closed
app.on('window-all-closed', () => {
app.quit()
})
Does anyone know solution for this error?

You most likely have a problem with your app.js script. You should hook onto some of the event listeners to understand what's really going on. There's an error, exit, close, disconnect, and message events you can listen for. You can also hook onto a number of other things such as the stdin, stdout, stderr as well. Checkout the documentation for the different events, hook onto all of them and output some information and you should be able to track down the issue.
You should also check to see if your express services runs properly directly from the command line rather than from within this Electron app. If it does then you've likely got a path wrong. This could be either that child_process cannot find the "node" application to run, or it can't find your startup script. In either case, you can use the path module to build up the correct path.

spawn ls ENOENT when watched file is modified

I am learning Node.js via the book Node.js the Right Way. I am trying to run the following example to watch changes to a file called target.txt that resides in the the same directory as the .js file.
"use strict";
const
fs = require('fs'),
spawn = require('child_process').spawn,
filename = process.argv[2];
if (!filename) {
throw Error("A file to watch must be specified!");
}
fs.watch(filename, function () {
let ls = spawn('ls', ['-lh', filename]);
ls.stdout.pipe(process.stdout);
});
console.log("Now watching " + filename + " for changes...");
I get the following error when I change the text file and save it:
events.js:160
throw er; // Unhandled 'error' event
^
Error: spawn ls ENOENT
at exports._errnoException (util.js:1018:11)
at Process.ChildProcess._handle.onexit (internal/child_process.js:193:32)
at onErrorNT (internal/child_process.js:367:16)
at _combinedTickCallback (internal/process/next_tick.js:80:11)
at process._tickCallback (internal/process/next_tick.js:104:9)
Node.js version: v6.11.0
IDE: Visual Studio Code 1.13.1
OS: Windows 10 64x

There's no ls on Windows, you should use dir instead.
However, that's not an executable. To run .bat and .cmd files you can:
Spawn cmd.exe and pass those files as arguments:
require('child_process').spawn('cmd', ['/c', 'dir']);
Use spawn with the shell option set to true:
require('child_process').spawn('dir', [], { shell: true });
Use exec instead of spawn:
require('child_process').exec('dir', (err, stdout, stderr) => { ... });
For more on that, take a look at this section in the official docs.
EDIT:
I'm not sure I understood you question in the comment correctly, but if you go for the second option, for example, you code will look like this:
...
fs.watch(filename, function () {
let dir = spawn('dir', [filename], { shell: true });
dir.stdout.pipe(process.stdout);
});
...
Please, keep in mind you may need to adjust this code slightly. I'm writing all this from memory as I don't have access to a Windows machine right now, so I can't test it myself.

node-transmission package not working

I tried installing this package : https://github.com/FLYBYME/node-transmission in my local nodejs installation but I am getting following error while running example.js from the above github repository.
Error: connect ECONNREFUSED 127.0.0.1:9091
at Object.exports._errnoException (util.js:1022:11)
at exports._exceptionWithHostPort (util.js:1045:20)
at TCPConnectWrap.afterConnect [as oncomplete] (net.js:1090:14)
code: 'ECONNREFUSED',
errno: 'ECONNREFUSED',
syscall: 'connect',
address: '127.0.0.1',
port: 9091
After a bit research I tried to run a server at port 9091 using this code(in a separate server.js file)
const http = require('http')
const port = 9091
const requestHandler = (request, response) => {
console.log(request.url)
response.end('Hello Node.js Server!')
}
const server = http.createServer(requestHandler)
server.listen(port, (err) => {
if (err) {
return console.log('something bad happened', err)
}
console.log(`server is listening on ${port}`)
})
After running a server on port 9091, I started getting this error with example.js :
SyntaxError: Unexpected token H in JSON at position 0
at JSON.parse (<anonymous>)
at IncomingMessage.onEnd (F:NodeJS\node-transmission-master\lib\transmission.js:453:33)
at emitNone (events.js:91:20)
at IncomingMessage.emit (events.js:185:7)
at endReadableNT (_stream_readable.js:974:12)
at _combinedTickCallback (internal/process/next_tick.js:74:11)
at process._tickCallback (internal/process/next_tick.js:98:9)
What must be causing this? I have no idea which step I have done wrong. That's why I described the whole process I followed.
I am very new to nodejs. Any help will be deeply appreciated.

The library is expecting a JSON formatted response and you are sending a simple text response. If you look through their source code you can see that their callServer function expects a stringified JSON but I can't see that in their docs.
You can change your code like so:
const http = require('http')
const port = 9091
const requestHandler = (request, response) => {
console.log(request.url)
// Format your response as a stringified JSON
response.end(JSON.stringify({message: 'Hello Node.js Server!'}));
}
const server = http.createServer(requestHandler)
server.listen(port, (err) => {
if (err) {
return console.log('something bad happened', err)
}
console.log(`server is listening on ${port}`)
})

In order to run the example from the node-transmission package, you need first to install and start the transmission-daemon.
The following steps are for Ubuntu:
Login as root or change to root with su - (be always careful what you do/install as root)
Install the transmission-daemon linux package: apt-get install transmission-daemon
Edit the daemon configuration for either disabling authentication or setting up your username/password (there is no default password). You can disable authentication by editing the relative flag in the configuration file:
pico /etc/transmission-daemon/settings.json
Set the auth flag to false: rpc-authentication-required:false
Press Ctrl-X then Y and then Enter to save the change
Start the daemon: start transmission-daemon
You should be able now to execute successfully the example.js and download its torrent link.