feat: modulesDir option

fixes problems with npx and linked libraries #1076

lib/builder/webpack/base.config.js

@@ -55,13 +55,13 @@ export default function webpackBaseConfig ({ isClient, isServer }) {
         'assets': join(this.options.srcDir, 'assets') // use in template with <img src="~assets/nuxt.png" />
       },
       modules: [
-        join(this.options.rootDir, 'node_modules'),
+        this.options.modulesDir,
         nodeModulesDir
       ]
     },
     resolveLoader: {
       modules: [
-        join(this.options.rootDir, 'node_modules'),
+        this.options.modulesDir,
         nodeModulesDir
       ]
     },

lib/builder/webpack/server.config.js

@@ -39,7 +39,8 @@ export default function webpackServerConfig () {
       // https://github.com/liady/webpack-node-externals
       nodeExternals({
         // load non-javascript files with extensions, presumably via loaders
-        whitelist: [/\.(?!(?:js|json)$).{1,5}$/i]
+        whitelist: [/\.(?!(?:js|json)$).{1,5}$/i],
+        modulesDir: this.options.modulesDir
       })
     ],
     plugins: (config.plugins || []).concat([

lib/common/options.js

@@ -25,8 +25,10 @@ export default function Options (_options) {
   _.defaultsDeep(options, Options.defaults)
 
   // Resolve dirs
-  options.rootDir = (typeof options.rootDir === 'string' && options.rootDir ? options.rootDir : process.cwd())
-  options.srcDir = (typeof options.srcDir === 'string' && options.srcDir ? resolve(options.rootDir, options.srcDir) : options.rootDir)
+  const hasValue = v => typeof v === 'string' && v
+  options.rootDir = hasValue(options.rootDir) ? options.rootDir : process.cwd()
+  options.srcDir = hasValue(options.srcDir) ? resolve(options.rootDir, options.srcDir) : options.rootDir
+  options.modulesDir = resolve(options.rootDir, hasValue(options.modulesDir) ? options.modulesDir : 'node_modules')
   options.buildDir = join(options.rootDir, options.buildDir)
 
   // If app.html is defined, set the template path to the user template