fix(webpack): don't use hashes when watching

helps preventing memory leaks on dev mode and more clear source

lib/builder/builder.js

@@ -204,6 +204,18 @@ export default class Builder {
     return options
   }
 
+  getFileName(name) {
+    let fileName = this.options.build.filenames[name]
+
+    // Don't use hashes when watching
+    // https://github.com/webpack/webpack/issues/1914#issuecomment-174171709
+    if (this.options.dev) {
+      fileName = fileName.replace(/\[(chunkhash|contenthash|hash)\]\./g, '')
+    }
+
+    return fileName
+  }
+
   async generateRoutesAndFiles() {
     debug('Generating files...')
     // -- Templates --

lib/builder/webpack/base.config.js

@@ -25,8 +25,8 @@ export default function webpackBaseConfig({ name, isServer }) {
     },
     output: {
       path: resolve(this.options.buildDir, 'dist'),
-      filename: this.options.build.filenames.app,
-      chunkFilename: this.options.build.filenames.chunk,
+      filename: this.getFileName('app'),
+      chunkFilename: this.getFileName('chunk'),
       publicPath: (isUrl(this.options.build.publicPath)
         ? this.options.build.publicPath
         : urlJoin(this.options.router.base, this.options.build.publicPath))
@@ -118,7 +118,7 @@ export default function webpackBaseConfig({ name, isServer }) {
   const extractCSS = this.options.build.extractCSS
   if (extractCSS) {
     const extractOptions = Object.assign(
-      { filename: this.options.build.filenames.css },
+      { filename: this.getFileName('css') },
       typeof extractCSS === 'object' ? extractCSS : {}
     )
     config.plugins.push(new ExtractTextPlugin(extractOptions))

lib/builder/webpack/client.config.js

@@ -73,7 +73,7 @@ export default function webpackClientConfig() {
     new webpack.optimize.CommonsChunkPlugin({
       name: 'manifest',
       minChunks: Infinity,
-      filename: this.options.build.filenames.manifest
+      filename: this.getFileName('manifest')
     })
   )
 
@@ -200,7 +200,7 @@ function commonChunksPlugin(config) {
   config.plugins.unshift(
     new webpack.optimize.CommonsChunkPlugin({
       name: 'vendor',
-      filename: this.options.build.filenames.vendor,
+      filename: this.getFileName('vendor'),
       minChunks(module, count) {
         // Detect and externalize well-known vendor if detected
         if (module.context && maybeVendor.some(v => module.context.includes(v))) {