replace Object.keys with mapModules, thx @c0defre4k

- follow @c0defre4k tip to use mapModules instead of Object.keys in search file

Author: Ffloriel

src/index.js

@@ -21,7 +21,6 @@ export default class PurgecssPlugin {
         // Go through chunks and purge as configured
         compilation.chunks.forEach(chunk => {
           const { name: chunkName, files } = chunk
-          const modules = chunk.mapModules(mod => mod)
           const assetsToPurge = search
             .assets(compilation.assets, ['.css'])
             .filter(asset => files.indexOf(asset.name) >= 0)
@@ -31,7 +30,7 @@ export default class PurgecssPlugin {
               .entries(entryPaths, chunkName)
               .concat(
                 search.files(
-                  modules,
+                  chunk,
                   this.options.moduleExtensions || [],
                   file => file.resource
                 )

src/search.js

@@ -1,29 +1,28 @@
 import path from 'path'
 
 export const assets = (assets = [], extensions = []) =>
-    Object.keys(assets)
-        .map(name => {
-            return (
-                extensions.indexOf(
-                    path.extname(
-                        name.indexOf('?') >= 0
-                            ? name.split('?').slice(0, -1).join('')
-                            : name
-                    )
-                ) >= 0 && { name, asset: assets[name] }
-            )
-        })
-        .filter(a => a)
+  Object.keys(assets)
+    .map(name => {
+      return (
+        extensions.indexOf(
+          path.extname(
+            name.indexOf('?') >= 0
+              ? name
+                  .split('?')
+                  .slice(0, -1)
+                  .join('')
+              : name
+          )
+        ) >= 0 && { name, asset: assets[name] }
+      )
+    })
+    .filter(a => a)
 
-export const files = (modules = {}, extensions = [], getter = a => a) =>
-    Object.keys(modules)
-        .map(name => {
-            const file = getter(modules[name])
-
-            if (!file) {
-                return null
-            }
-
-            return extensions.indexOf(path.extname(file)) >= 0 && file
-        })
-        .filter(a => a)
+export const files = (chunk, extensions = [], getter = a => a) =>
+  chunk
+    .mapModules(module => {
+      const file = getter(module)
+      if (!file) return null
+      return extensions.indexOf(path.extname(file)) >= 0 && file
+    })
+    .filter(a => a)