generate module id from project root to ensure consistent hash regardless of project path (close #613)

Author: yyx990803

lib/gen-id.js

@@ -1,8 +1,13 @@
 // utility for generating a uid for each component file
 // used in scoped CSS rewriting
+var path = require('path')
 var hash = require('hash-sum')
 var cache = Object.create(null)
 
-module.exports = function genId (file) {
+module.exports = function genId (file, context) {
+  context = context || process.cwd()
+  var contextPath = context.split(path.sep)
+  var rootId = contextPath[contextPath.length - 1]
+  file = rootId + '/' + path.relative(context, file)
   return cache[file] || (cache[file] = hash(file))
 }

lib/loader.js

@@ -60,7 +60,7 @@ module.exports = function (content) {
 
   var filePath = this.resourcePath
   var fileName = path.basename(filePath)
-  var moduleId = 'data-v-' + genId(filePath)
+  var moduleId = 'data-v-' + genId(filePath, this._compiler.context)
   var styleRewriter = styleRewriterPath + '?id=' + moduleId
 
   var cssLoaderOptions = ''