if opts.projectName is defined, prevent to read the pkgPath file

[ctxhou]

Hi, I would like to suggest whether conf can prevent read the pkgPath file if the opts.projectName is defined.

Now the lib uses this way to set the pkgPath link

options = Object.assign({
  // Can't use `require` because of Webpack being annoying:
  // https://github.com/webpack/webpack/issues/196
  projectName: pkgPath && JSON.parse(fs.readFileSync(pkgPath, 'utf8')).name
}, options);

if (!options.projectName && !options.cwd) {
  throw new Error('Project name could not be inferred. Please specify the `projectName` option.');
}

I think whether it can exam the option first?
The reason is I use the electron-store, and in some cases, I don't know why it loads the pkgPath as root system path (e.g.: /Users/<UserName>/pacakge.json). This will cause the permission issues.
If we can exam the projectName first, we can prevent the conf to automatically load the pkgPath.

So the change would be:

options = Object.assign({
  // Can't use `require` because of Webpack being annoying:
  // https://github.com/webpack/webpack/issues/196
  projectName: options.projectName ? options.projectName : pkgPath && JSON.parse(fs.readFileSync(pkgPath, 'utf8')).name
}, options);

if (!options.projectName && !options.cwd) {
  throw new Error('Project name could not be inferred. Please specify the `projectName` option.');
}

[sindresorhus]

Sure, PR welcome, but really no point in having it in the Object.assign call at all then. Can just be:

options = Object.assign({}, options);

if (!options.projectName) {
	// Can't use `require` because of Webpack being annoying:
	// https://github.com/webpack/webpack/issues/196
	options.projectName = pkgPath && JSON.parse(fs.readFileSync(pkgPath, 'utf8')).name;
}

[sindresorhus]

The reason is I use the electron-store, and in some cases, I don't know why it loads the pkgPath as root system path (e.g.: /Users//pacakge.json).

Can you reproduce the issue reliably? Would be good to get that fixed for real instead of just hiding it away.

[ctxhou]

Yeah, I also hope to fix the real problem, but it's hard for me to reproduce, because I only received this error report from one of the users. I will write down all things I knew so that we can discuss the possible bug.

---

Here is the case:

• The app is published on Mac App Store
• Mac version: High Sierra (10.13)

Error message:

Uncaught Exception:
Error: EPERM: operation not permitted, open '/Users/<username>/package.json'
	at Object.fs.openSync(fs.js:645:18)
	at Object.module(anonymous function)[as openSync]
	at Object.fs.readFileSync(fs.js:551:33)
...

Here is how I declare the electron-store. It's the same with the document.

import Store from 'electron-store';
const store = new Store();

I think the possible reason is that pkgPath guess the wrong path. However, this is a special case. It only occurred in this user's case.