fix: postcss-uniapp-plugin support postcss8

packages/vue-cli-plugin-uni/package.json

@@ -29,7 +29,6 @@
     "mkdirp": "^0.5.1",
     "module-alias": "^2.1.0",
     "neo-async": "^2.6.1",
-    "postcss": "^7.0.7",
     "postcss-import": "^12.0.1",
     "postcss-selector-parser": "^5.0.0",
     "postcss-value-parser": "^3.3.1",
@@ -39,5 +38,8 @@
     "wrap-loader": "^0.2.0",
     "xregexp": "4.0.0"
   },
+  "peerDependencies": {
+    "postcss": ">=7"
+  },
   "gitHead": "9e2d0f8e244724fcd64880316c57d837d1778cf8"
 }

packages/vue-cli-plugin-uni/packages/postcss/index.js

@@ -156,7 +156,7 @@ if (process.env.UNI_USING_V3) {
    * 转换 upx
    * 转换 px
    */
-  module.exports = postcss.plugin('postcss-uniapp-plugin', function (opts) {
+  const fn = function (opts) {
     opts = {
       ...defaultOpts,
       ...opts
@@ -265,5 +265,20 @@ if (process.env.UNI_USING_V3) {
         })
       }
     }
-  })
+  }
+
+  const version = Number(require('postcss/package.json').version.split('.')[0])
+
+  if (version < 8) {
+    module.exports = postcss.plugin('postcss-uniapp-plugin', fn)
+  } else {
+    module.exports = function (opts) {
+      return {
+        postcssPlugin: 'postcss-uniapp-plugin',
+        Once: fn(opts)
+      }
+    }
+
+    module.exports.postcss = true
+  }
 }

packages/vue-cli-plugin-uni/packages/postcss/index.v3.js

-const postcss = require('postcss')
 const selectorParser = require('postcss-selector-parser')
 
 const TAGS = Object.keys(require('@dcloudio/uni-cli-shared').tags)
@@ -14,8 +13,7 @@ const isInsideKeyframes = function (rule) {
 
 let rewriteUrl
 
-module.exports = postcss.plugin('postcss-uniapp-plugin', function (opts) {
-  return function (root, result) {
+function once (root) {
   if (!rewriteUrl) {
     rewriteUrl = require('@dcloudio/uni-cli-shared/lib/url-loader').rewriteUrl
   }
@@ -43,5 +41,22 @@ module.exports = postcss.plugin('postcss-uniapp-plugin', function (opts) {
       )
     }
   })
+}
+
+const version = Number(require('postcss/package.json').version.split('.')[0])
+
+if (version < 8) {
+  const postcss = require('postcss')
+  module.exports = postcss.plugin('postcss-uniapp-plugin', function (opts) {
+    return once
+  })
+} else {
+  module.exports = function (opts) {
+    return {
+      postcssPlugin: 'postcss-uniapp-plugin',
+      Once: once
     }
-})
+  }
+
+  module.exports.postcss = true
+}