stdout of spawned child process is truncated or gone. Extension doesn't get the output of the command.

[juanfe-google]

• VSCode Version:
  Version 1.21.1 (1.21.1)
• OS Version:
  OSX 10.13.3 (17D102)

The root of the issue is in nodeJS: nodejs/node#6379

Steps to Reproduce:

1. Use child_process.spawn, or any other child process function in nodejs.
2. See the output of stdout in the extension.

Example:
const proc = require('child_process').spawnSync('git', ['status']); console.log(String(proc.stdout));

[kenny-y]

Not sure this is gonna help or not: AFAIK, console.log() won't be able to write too much data in a short amount of time, and it's async (on pipes). Use process.stdout.write() and when it returns false, you'll have to wait on drain event before you can write more data.

[alexdima]

@juanfe-google

We are using spawn and exec in our own built-in git extension like here or here and AFAIK that works fine for us.

So perhaps it is a problem with spawnSync ? (which is a horrible variant to use, as it blocks the entire EH process)

[juanfe-google]

@alexandrudima In the tool I'm working on uses spawn instead of spawnSync (which was chosen to simplify the example).

The issue is specific to nodeJS running on OSX. nodejs/node#2360

[alexdima]

ping @joaomoreno

Is there some magic sauce you're using when spawning git such that you always get the entire output?

[joaomoreno]

No, not really... Just regular old spawn.

[alexdima]

@juanfe-google I cannot reproduce the problem you are describing. I'm using an extension with the following contents:

• package.json

{
    "publisher": "alex",
    "name": "46002",
    "version": "0.0.0",
    "engines": {
        "vscode": "^1.0.0"
    },
    "activationEvents": [
        "*"
    ],
    "main": "index.js"
}

• index.js

const cp = require('child_process');
const vscode = require('vscode');

const proc = cp.spawnSync('git', ['status'], {
    cwd: vscode.workspace.rootPath
});
console.log(String(proc.stdout));

And I see the entire output of git status in the VS Code Developer Tools Console.

[juanfe-google]

@alexandrudima what Mac OS X version are you running?

[alexdima]

I am using macOS High Sierra, Version 10.13.4. Would this be something that reproduces only on certain macOS versions?

[vscodebot]

This issue has been closed automatically because it needs more information and has not had recent activity. See also our issue reporting guidelines.

Happy Coding!