Get environment variables from npm

[TiagoDanin]

Fixes #4 Note: "Config values are case-insensitive" (NPM Config Docs: https://docs.npmjs.com/misc/config)

[TiagoDanin]

Problem in Travis CI: XO did not work with node V4

[sindresorhus]

Can you add a test?

[TiagoDanin]

@sindresorhus Two problems: Sugestions?

• The process.env in test.js with import is not loading in index.js

• Required reloads the package for different tests

• test.a.js (All Falid!)

  
  import test from 'ava';
  import execa from 'execa';
  import globalDirs from '.';

console.log(globalDirs);

const npm = arguments => execa.stdout('npm', arguments);

test('npm.prefix with env', async t => { process.env.npm_config_PREFIX = '/usr/local/lib' t.is(globalDirs.npm.prefix, '/usr/local/lib'); }); //... all tests ...//

- test.b.js (Working "npm.prefix with env" and others falid!)
```js
const test = require('ava');
const execa = require('execa');

const npm = arguments_ => execa.stdout('npm', arguments_);

test('npm.prefix with env', async t => {
    process.env.npm_config_PREFIX = '/usr/local/lib';
    const globalDirs = require('.');
    console.log(globalDirs);
    t.is(globalDirs.npm.prefix, '/usr/local/lib');
});
//... all tests ...//

• test.c.js (All falid!)

  
  const test = require('ava');
  const execa = require('execa');
  const globalDirs = require('.');

console.log(globalDirs);

const npm = arguments => execa.stdout('npm', arguments);

test('npm.prefix with env', async t => { process.env.npm_config_PREFIX = '/usr/local/lib'; const globalDirsEnv = require('.'); t.is(globalDirsEnv.npm.prefix, '/usr/local/lib'); }); //... all tests ...//

[TiagoDanin]

@sindresorhus Done! Added new test.

[sindresorhus]

I don't want to expose a .reload() method just for testing purposes. The correct solution is to use something like https://github.com/sindresorhus/import-fresh