Add optimizer plugin for new CSS compiler

packages/core/diagnostic/src/diagnostic.js

@@ -177,7 +177,10 @@ export function errorToDiagnostic(
       origin: defaultValues?.origin ?? 'Error',
       message: escapeMarkdown(error.message),
       name: error.name,
-      stack: error.highlightedCodeFrame ?? error.codeFrame ?? error.stack,
+      stack:
+        codeFrames == null
+          ? error.highlightedCodeFrame ?? error.codeFrame ?? error.stack
+          : undefined,
       codeFrames,
     },
   ];

packages/optimizers/css/package.json

@@ -0,0 +1,29 @@
+{
+  "name": "@parcel/optimizer-css",
+  "version": "2.0.1",
+  "license": "MIT",
+  "publishConfig": {
+    "access": "public"
+  },
+  "funding": {
+    "type": "opencollective",
+    "url": "https://opencollective.com/parcel"
+  },
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/parcel-bundler/parcel.git"
+  },
+  "main": "lib/CSSOptimizer.js",
+  "source": "src/CSSOptimizer.js",
+  "engines": {
+    "node": ">= 12.0.0",
+    "parcel": "^2.0.1"
+  },
+  "dependencies": {
+    "@parcel/css": "1.0.0-alpha.4",
+    "@parcel/plugin": "^2.0.1",
+    "@parcel/source-map": "^2.0.0",
+    "@parcel/utils": "^2.0.1",
+    "browserslist": "^4.6.6"
+  }
+}

packages/optimizers/css/src/CSSOptimizer.js

@@ -0,0 +1,110 @@
+// @flow strict-local
+
+import SourceMap from '@parcel/source-map';
+import {Optimizer} from '@parcel/plugin';
+// $FlowFixMe
+import {transform} from '@parcel/css';
+import {blobToBuffer} from '@parcel/utils';
+import browserslist from 'browserslist';
+
+export default (new Optimizer({
+  async optimize({
+    bundle,
+    contents: prevContents,
+    getSourceMapReference,
+    map: prevMap,
+    options,
+  }) {
+    if (!bundle.env.shouldOptimize) {
+      return {contents: prevContents, map: prevMap};
+    }
+
+    let targets = getTargets(bundle.env.engines.browsers);
+    let code = await blobToBuffer(prevContents);
+    let result = transform({
+      filename: bundle.name,
+      code,
+      minify: true,
+      source_map: !!bundle.env.sourceMap,
+      targets,
+    });
+
+    let map;
+    if (result.map != null) {
+      map = new SourceMap(options.projectRoot);
+      map.addVLQMap(JSON.parse(result.map));
+    }
+
+    let contents = result.code;
+    if (bundle.env.sourceMap) {
+      let reference = await getSourceMapReference(map);
+      if (reference != null) {
+        contents += '\n' + '/*# sourceMappingURL=' + reference + ' */\n';
+      }
+    }
+
+    return {
+      contents,
+      map,
+    };
+  },
+}): Optimizer);
+
+const BROWSER_MAPPING = {
+  and_chr: 'chrome',
+  and_ff: 'firefox',
+  ie_mob: 'ie',
+  op_mob: 'opera',
+  and_qq: null,
+  and_uc: null,
+  baidu: null,
+  bb: null,
+  kaios: null,
+  op_mini: null,
+};
+
+let cache = new Map();
+
+function getTargets(browsers) {
+  if (browsers == null) {
+    return undefined;
+  }
+
+  let cached = cache.get(browsers);
+  if (cached != null) {
+    return cached;
+  }
+
+  let targets = {};
+  for (let browser of browserslist(browsers)) {
+    let [name, v] = browser.split(' ');
+    if (BROWSER_MAPPING[name] === null) {
+      continue;
+    }
+
+    let version = parseVersion(v);
+    if (version == null) {
+      continue;
+    }
+
+    if (targets[name] == null || version < targets[name]) {
+      targets[name] = version;
+    }
+  }
+
+  cache.set(browsers, targets);
+  return targets;
+}
+
+function parseVersion(version) {
+  let [major, minor = 0, patch = 0] = version
+    .split('-')[0]
+    .split('.')
+    .map(v => parseInt(v, 10));
+
+  if (isNaN(major) || isNaN(minor) || isNaN(patch)) {
+    return null;
+  }
+
+  return (major << 16) | (minor << 8) | patch;
+}

yarn.lock

@@ -2133,6 +2133,13 @@
   dependencies:
     "@octokit/openapi-types" "^6.2.0"
 
+"@parcel/css@1.0.0-alpha.4":
+  version "1.0.0-alpha.4"
+  resolved "https://registry.yarnpkg.com/@parcel/css/-/css-1.0.0-alpha.4.tgz#967520401053f8eb0d5f23ed58b4afbcebc6c9de"
+  integrity sha512-/wd7WWesAekEexrL7slIkb1gNXX/XYF8bMZUEcEKjDdkfne5SyINLTGbV3WzvsEjzRwgBL5kBET5nX59GJ3JVg==
+  dependencies:
+    detect-libc "^1.0.3"
+
 "@parcel/source-map@^2.0.0":
   version "2.0.0"
   resolved "https://registry.yarnpkg.com/@parcel/source-map/-/source-map-2.0.0.tgz#41cf004109bbf277ceaf096a58838ff6a59af774"