refactor: add build.postcss.preset config

lib/builder/webpack/utils/postcss.js

@@ -43,10 +43,7 @@ export default class PostcssConfig {
         'postcss-url': {},
 
         // https://github.com/csstools/postcss-preset-env
-        'postcss-preset-env': {
-          // https://cssdb.org/#staging-process
-          stage: 2
-        },
+        'postcss-preset-env': this.preset || {},
         'cssnano': this.dev ? false : { preset: 'default' }
       }
     }
@@ -114,6 +111,10 @@ export default class PostcssConfig {
 
     // Apply default plugins
     if (isPureObject(config)) {
+      if (config.preset) {
+        this.preset = config.preset
+        delete config.preset
+      }
       _.defaults(config, this.defaultConfig)
 
       this.loadPlugins(config)

lib/common/nuxt.config.js

@@ -76,7 +76,12 @@ export default {
     },
     transpile: [], // Name of NPM packages to be transpiled
     vueLoader: {},
-    postcss: {},
+    postcss: {
+      preset: {
+        // https://cssdb.org/#staging-process
+        stage: 2
+      }
+    },
     templates: [],
     watch: [],
     devMiddleware: {},

package.json

@@ -74,7 +74,6 @@
     "@nuxtjs/babel-preset-app": "^0.3.0",
     "@nuxtjs/friendly-errors-webpack-plugin": "^2.0.2",
     "@nuxtjs/youch": "^4.2.3",
-    "autoprefixer": "^8.6.5",
     "babel-loader": "^8.0.0-beta",
     "cache-loader": "^1.2.2",
     "caniuse-lite": "^1.0.30000874",

test/fixtures/with-config/nuxt.config.js

@@ -72,6 +72,16 @@ export default {
       return Object.assign({}, config, {
         devtool: 'nosources-source-map'
       })
+    },
+    postcss: {
+      preset: {
+        features: {
+          'custom-selectors': true
+        },
+        autoprefixer: {
+          grid: true
+        }
+      }
     }
   },
   css: [{ src: '~/assets/app.css' }],

yarn.lock

@@ -1216,17 +1216,6 @@ autoprefixer@^8.5.0:
     postcss "^6.0.22"
     postcss-value-parser "^3.2.3"
 
-autoprefixer@^8.6.5:
-  version "8.6.5"
-  resolved "https://registry.yarnpkg.com/autoprefixer/-/autoprefixer-8.6.5.tgz#343f3d193ed568b3208e00117a1b96eb691d4ee9"
-  dependencies:
-    browserslist "^3.2.8"
-    caniuse-lite "^1.0.30000864"
-    normalize-range "^0.1.2"
-    num2fraction "^1.2.2"
-    postcss "^6.0.23"
-    postcss-value-parser "^3.2.3"
-
 aws-sign2@~0.7.0:
   version "0.7.0"
   resolved "https://registry.yarnpkg.com/aws-sign2/-/aws-sign2-0.7.0.tgz#b46e890934a9591f2d2f6f86d7e6a9f1b3fe76a8"
@@ -1725,7 +1714,7 @@ caniuse-api@^3.0.0:
     lodash.memoize "^4.1.2"
     lodash.uniq "^4.5.0"
 
-caniuse-lite@^1.0.0, caniuse-lite@^1.0.30000864, caniuse-lite@^1.0.30000865, caniuse-lite@^1.0.30000874:
+caniuse-lite@^1.0.0, caniuse-lite@^1.0.30000865, caniuse-lite@^1.0.30000874:
   version "1.0.30000874"
   resolved "https://registry.yarnpkg.com/caniuse-lite/-/caniuse-lite-1.0.30000874.tgz#a641b1f1c420d58d9b132920ef6ba87bbdcd2223"