feat: support css @import hmr (vitejs#281)

package.json

@@ -84,6 +84,7 @@
     "open": "^7.0.3",
     "ora": "^4.0.4",
     "postcss": "^7.0.28",
+    "postcss-import": "^12.0.1",
     "postcss-load-config": "^2.1.0",
     "postcss-modules": "^2.0.0",
     "resolve": "^1.17.0",
@@ -103,6 +104,7 @@
     "@types/hash-sum": "^1.0.0",
     "@types/jest": "^25.2.1",
     "@types/node": "^13.13.1",
+    "@types/postcss-import": "^12.0.0",
     "@types/postcss-load-config": "^2.0.1",
     "@types/serve-handler": "^6.1.0",
     "@types/ws": "^7.2.4",

playground/App.vue

@@ -14,6 +14,7 @@
   <TestPostCss />
   <TestScopedCss />
   <TestCssModules />
+  <TestCssAtImport/>
   <TestPreprocessors />
   <TestAssets />
   <TestSrcImport />
@@ -42,6 +43,7 @@ import TestJsx from './TestJsx.vue'
 import TestAlias from './TestAlias.vue'
 import TestTransform from './TestTransform.vue'
 import TestRewriteOptimized from "./rewrite-optimized/TestRewriteOptimized.vue";
+import TestCssAtImport from './css-@import/TestCssAtImport.vue'
 
 export default {
   data: () => ({
@@ -56,6 +58,7 @@ export default {
     TestScopedCss,
     TestCssModules,
     TestPreprocessors,
+    TestCssAtImport,
     TestSrcImport,
     TestAssets,
     TestJsonImport,

playground/css-@import/TestCssAtImport.vue

@@ -0,0 +1,19 @@
+<template>
+  <h2>CSS @import</h2>
+  <div class="sfc-style-at-import">
+    &lt;style @import &gt; this should be red
+  </div>
+  <div class="script-at-import">
+    &lt;script @import &gt; this should be green
+  </div>
+</template>
+
+<style scoped>
+@import './testCssAtImportFromStyle.css';
+</style>
+
+<script>
+import './testCssAtImportFromScript.css'
+
+export default {}
+</script>

playground/css-@import/imported.css

@@ -0,0 +1,3 @@
+.script-at-import {
+  color: green;
+}

playground/css-@import/testCssAtImportFromScript.css

@@ -0,0 +1 @@
+@import './imported.css'

playground/css-@import/testCssAtImportFromStyle.css

@@ -0,0 +1,3 @@
+.sfc-style-at-import {
+  color: red;
+}

src/node/build/buildPluginCss.ts

@@ -34,7 +34,7 @@ export const createBuildCssPlugin = (
         const result = await compileCss(root, id, {
           id: '',
           source: css,
-          filename: path.basename(id),
+          filename: id,
           scoped: false,
           modules: id.endsWith('.module.css'),
           preprocessLang: id.replace(cssPreprocessLangRE, '$2') as any

src/node/server/serverPluginCss.ts

@@ -7,7 +7,9 @@ import { srcImportMap, vueCache } from './serverPluginVue'
 import {
   codegenCss,
   compileCss,
+  cssImportMap,
   cssPreprocessLangRE,
+  getCssImportBoundaries,
   rewriteCssUrls
 } from '../utils/cssUtils'
 import qs from 'querystring'
@@ -55,7 +57,11 @@ export const cssPlugin: ServerPlugin = ({ root, app, watcher, resolver }) => {
       const publicPath = resolver.fileToRequest(filePath)
 
       /** filter unused files */
-      if (!processedCSS.has(publicPath) && !srcImportMap.has(filePath)) {
+      if (
+        !cssImportMap.has(filePath) &&
+        !processedCSS.has(publicPath) &&
+        !srcImportMap.has(filePath)
+      ) {
         return debugCSS(
           `${basename(publicPath)} has changed, but it is not currently in use`
         )
@@ -66,45 +72,69 @@ export const cssPlugin: ServerPlugin = ({ root, app, watcher, resolver }) => {
         // it cannot be handled as simple css import because it may be scoped
         const styleImport = srcImportMap.get(filePath)
         vueCache.del(filePath)
-        const publicPath = cleanUrl(styleImport)
-        const index = qs.parse(styleImport.split('?', 2)[1]).index
-        console.log(
-          chalk.green(`[vite:hmr] `) + `${publicPath} updated. (style)`
-        )
-        watcher.send({
-          type: 'style-update',
-          path: `${publicPath}?type=style&index=${index}`,
-          timestamp: Date.now()
-        })
+        vueStyleUpdate(styleImport)
         return
       }
       // handle HMR for module.css
-      // it cannot process with normal css, the class which in module.css maybe removed
+      // it cannot be handled as normal css because the js exports may change
       if (filePath.endsWith('.module.css')) {
-        watcher.handleJSReload(filePath, Date.now())
+        moduleCssUpdate(filePath)
         return
       }
 
-      // bust process cache
-      processedCSS.delete(publicPath)
-
-      watcher.send({
-        type: 'style-update',
-        path: publicPath,
-        timestamp: Date.now()
-      })
+      const boundaries = getCssImportBoundaries(filePath)
+      if (boundaries.size) {
+        for (let boundary of boundaries) {
+          if (boundary.includes('.module')) {
+            moduleCssUpdate(boundary)
+          } else if (boundary.includes('.vue')) {
+            vueCache.del(cleanUrl(boundary))
+            vueStyleUpdate(resolver.fileToRequest(boundary))
+          } else {
+            normalCssUpdate(resolver.fileToRequest(boundary))
+          }
+        }
+        return
+      }
+      // no boundaries
+      normalCssUpdate(publicPath)
     }
   })
 
-  async function processCss(root: string, ctx: Context) {
-    let css = (await readBody(ctx.body))!
+  function vueStyleUpdate(styleImport: string) {
+    const publicPath = cleanUrl(styleImport)
+    const index = qs.parse(styleImport.split('?', 2)[1]).index
+    console.log(chalk.green(`[vite:hmr] `) + `${publicPath} updated. (style)`)
+    watcher.send({
+      type: 'style-update',
+      path: `${publicPath}?type=style&index=${index}`,
+      timestamp: Date.now()
+    })
+  }
 
+  function moduleCssUpdate(filePath: string) {
+    watcher.handleJSReload(filePath)
+  }
+
+  function normalCssUpdate(publicPath: string) {
+    // bust process cache
+    processedCSS.delete(publicPath)
+
+    watcher.send({
+      type: 'style-update',
+      path: publicPath,
+      timestamp: Date.now()
+    })
+  }
+
+  async function processCss(root: string, ctx: Context) {
+    const css = (await readBody(ctx.body))!
     const result = await compileCss(root, ctx.path, {
       id: '',
       source: css,
       filename: resolver.requestToFile(ctx.path),
       scoped: false,
-      modules: ctx.path.endsWith('.module.css'),
+      modules: ctx.path.includes('.module'),
       preprocessLang: ctx.path.replace(cssPreprocessLangRE, '$2') as any
     })
 

src/node/server/serverPluginVue.ts

@@ -514,10 +514,9 @@ async function compileSFCStyle(
   const start = Date.now()
 
   const { generateCodeFrame } = resolveCompiler(root)
-
   const result = (await compileCss(root, publicPath, {
     source: style.content,
-    filename: filePath,
+    filename: filePath + `?type=style&index=${index}`,
     id: ``, // will be computed in compileCss
     scoped: style.scoped != null,
     modules: style.module != null,

src/node/utils/cssUtils.ts

@@ -54,15 +54,24 @@ export async function compileCss(
   }: SFCAsyncStyleCompileOptions
 ): Promise<SFCStyleCompileResults | string> {
   const id = hash_sum(publicPath)
-  const postcssConfig = await loadPostcssConfig(root)
+  let postcssConfig = await loadPostcssConfig(root)
   const { compileStyleAsync } = resolveCompiler(root)
 
-  if (publicPath.endsWith('.css') && !modules && !postcssConfig) {
+  if (
+    publicPath.endsWith('.css') &&
+    !modules &&
+    !postcssConfig &&
+    !source.includes('@import')
+  ) {
     // no need to invoke compile for plain css if no postcss config is present
     return source
   }
 
-  return await compileStyleAsync({
+  const postcssOptions = postcssConfig && postcssConfig.options
+  const postcssPlugins = postcssConfig ? postcssConfig.plugins : []
+  postcssPlugins.push(require('postcss-import')())
+
+  const res = await compileStyleAsync({
     source,
     filename,
     id: `data-v-${id}`,
@@ -71,18 +80,32 @@ export async function compileCss(
     modulesOptions: {
       generateScopedName: `[local]_${id}`
     },
+
     preprocessLang: preprocessLang,
     preprocessCustomRequire: (id: string) => require(resolveFrom(root, id)),
-    ...(postcssConfig
-      ? {
-          postcssOptions: postcssConfig.options,
-          postcssPlugins: postcssConfig.plugins
-        }
-      : {}),
     preprocessOptions: {
       includePaths: ['node_modules']
-    }
+    },
+
+    postcssOptions,
+    postcssPlugins
   })
+
+  // record css import dependencies
+  if (res.rawResult) {
+    res.rawResult.messages.forEach((msg) => {
+      let { type, file, parent } = msg
+      if (type === 'dependency') {
+        if (cssImportMap.has(file)) {
+          cssImportMap.get(file)!.add(parent)
+        } else {
+          cssImportMap.set(file, new Set([parent]))
+        }
+      }
+    })
+  }
+
+  return res
 }
 
 export function codegenCss(
@@ -126,3 +149,23 @@ async function loadPostcssConfig(
     return (cachedPostcssConfig = null)
   }
 }
+
+export const cssImportMap = new Map<
+  string /*filePath*/,
+  Set<string /*filePath*/>
+>()
+
+export function getCssImportBoundaries(
+  filePath: string,
+  boundaries = new Set<string>()
+) {
+  if (!cssImportMap.has(filePath)) {
+    return boundaries
+  }
+  const importers = cssImportMap.get(filePath)!
+  for (const importer of importers) {
+    boundaries.add(importer)
+    getCssImportBoundaries(importer, boundaries)
+  }
+  return boundaries
+}

test/test.js

@@ -234,6 +234,29 @@ describe('vite', () => {
       }
     })
 
+    test('CSS @import', async () => {
+      const el = await page.$('.script-at-import')
+      expect(await getComputedColor(el)).toBe('rgb(0, 128, 0)')
+      if (!isBuild) {
+        await updateFile('css-@import/imported.css', (content) =>
+          content.replace('green', 'rgb(0, 0, 0)')
+        )
+        await expectByPolling(() => getComputedColor(el), 'rgb(0, 0, 0)')
+      }
+    })
+
+    test('SFC <style> w/ @import', async () => {
+      const el = await page.$('.sfc-style-at-import')
+      expect(await getComputedColor(el)).toBe('rgb(255, 0, 0)')
+      if (!isBuild) {
+        await updateFile(
+          'css-@import/testCssAtImportFromStyle.css',
+          (content) => content.replace('red', 'rgb(0, 0, 0)')
+        )
+        await expectByPolling(() => getComputedColor(el), 'rgb(0, 0, 0)')
+      }
+    })
+
     test('import *.module.css', async () => {
       const el = await page.$('.css-modules-import')
       expect(await getComputedColor(el)).toBe('rgb(255, 140, 0)')

yarn.lock

@@ -743,6 +743,13 @@
   resolved "https://registry.yarnpkg.com/@types/parse-json/-/parse-json-4.0.0.tgz#2f8bb441434d163b35fb8ffdccd7138927ffb8c0"
   integrity sha512-//oorEZjL6sbPcKUaCdIGlIUeH26mgzimjBB77G6XRgnDl/L5wOnpyBGRe/Mmf5CVW3PwEBE1NjiMZ/ssFh4wA==
 
+"@types/postcss-import@^12.0.0":
+  version "12.0.0"
+  resolved "https://registry.npmjs.org/@types/postcss-import/-/postcss-import-12.0.0.tgz#d7c584b2651258ed5b3657d25467df1c4aec33e1"
+  integrity sha512-AFgOR4zOOp/izuY7n5aEr/0SJ5e8fNYVxMkx49IA3Jf/Bs6Hhd6staMoSkdiTr9fi0z3Q1Ts5SqpFI5vv4k7BQ==
+  dependencies:
+    postcss "^7.0.27"
+
 "@types/postcss-load-config@^2.0.1":
   version "2.0.1"
   resolved "https://registry.yarnpkg.com/@types/postcss-load-config/-/postcss-load-config-2.0.1.tgz#76c789032dfc6823eab1900ad7cc95ebadf24d49"
@@ -5467,6 +5474,16 @@ postcss-discard-overridden@^4.0.1:
   dependencies:
     postcss "^7.0.0"
 
+postcss-import@^12.0.1:
+  version "12.0.1"
+  resolved "https://registry.npmjs.org/postcss-import/-/postcss-import-12.0.1.tgz#cf8c7ab0b5ccab5649024536e565f841928b7153"
+  integrity sha512-3Gti33dmCjyKBgimqGxL3vcV8w9+bsHwO5UrBawp796+jdardbcFl4RP5w/76BwNL7aGzpKstIfF9I+kdE8pTw==
+  dependencies:
+    postcss "^7.0.1"
+    postcss-value-parser "^3.2.3"
+    read-cache "^1.0.0"
+    resolve "^1.1.7"
+
 postcss-load-config@^2.1.0:
   version "2.1.0"
   resolved "https://registry.yarnpkg.com/postcss-load-config/-/postcss-load-config-2.1.0.tgz#c84d692b7bb7b41ddced94ee62e8ab31b417b003"
@@ -5733,7 +5750,7 @@ postcss-unique-selectors@^4.0.1:
     postcss "^7.0.0"
     uniqs "^2.0.0"
 
-postcss-value-parser@^3.0.0:
+postcss-value-parser@^3.0.0, postcss-value-parser@^3.2.3:
   version "3.3.1"
   resolved "https://registry.yarnpkg.com/postcss-value-parser/-/postcss-value-parser-3.3.1.tgz#9ff822547e2893213cf1c30efa51ac5fd1ba8281"
   integrity sha512-pISE66AbVkp4fDQ7VHBwRNXzAAKJjw4Vw7nWI/+Q3vuly7SNfgYXvm6i5IgFylHGK5sP/xHAbB7N49OS4gWNyQ==
@@ -6000,6 +6017,13 @@ react-is@^16.12.0:
   resolved "https://registry.yarnpkg.com/react-is/-/react-is-16.13.1.tgz#789729a4dc36de2999dc156dd6c1d9c18cea56a4"
   integrity sha512-24e6ynE2H+OKt4kqsOvNd8kBpV65zoxbA4BVsEOB3ARVWQki/DHzaUoC5KuON/BiccDaCCTZBuOcfZs70kR8bQ==
 
+read-cache@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.npmjs.org/read-cache/-/read-cache-1.0.0.tgz#e664ef31161166c9751cdbe8dbcf86b5fb58f774"
+  integrity sha1-5mTvMRYRZsl1HNvo28+GtftY93Q=
+  dependencies:
+    pify "^2.3.0"
+
 read-pkg-up@^1.0.1:
   version "1.0.1"
   resolved "https://registry.yarnpkg.com/read-pkg-up/-/read-pkg-up-1.0.1.tgz#9d63c13276c065918d57f002a57f40a1b643fb02"
@@ -6276,7 +6300,7 @@ resolve@1.1.7:
   resolved "https://registry.yarnpkg.com/resolve/-/resolve-1.1.7.tgz#203114d82ad2c5ed9e8e0411b3932875e889e97b"
   integrity sha1-IDEU2CrSxe2ejgQRs5ModeiJ6Xs=
 
-resolve@^1.1.6, resolve@^1.10.0, resolve@^1.11.0, resolve@^1.14.2, resolve@^1.17.0, resolve@^1.3.2:
+resolve@^1.1.6, resolve@^1.1.7, resolve@^1.10.0, resolve@^1.11.0, resolve@^1.14.2, resolve@^1.17.0, resolve@^1.3.2:
   version "1.17.0"
   resolved "https://registry.yarnpkg.com/resolve/-/resolve-1.17.0.tgz#b25941b54968231cc2d1bb76a79cb7f2c0bf8444"
   integrity sha512-ic+7JYiV8Vi2yzQGFWOkiZD5Z9z7O2Zhm9XMaTxdJExKasieFCr+yXZ/WmXsckHiKl12ar0y6XiXDx3m4RHn1w==