feat(postcss-purgecss): remove compatibility with postcss 7

 #488
fix #540

BREAKING CHANGE: dropping support for postcss 7

packages/postcss-purgecss/__tests__/index.test.ts

@@ -1,6 +1,5 @@
 import fs from "fs";
-import { UserDefinedOptions } from "../src/types";
-import postcss, { PluginCreator } from "postcss";
+import postcss from "postcss";
 
 import purgeCSSPlugin from "../src/";
 
@@ -16,7 +15,7 @@ describe("Purgecss postcss plugin", () => {
         .readFileSync(`${__dirname}/fixtures/expected/${file}.css`)
         .toString();
       const result = await postcss([
-        (purgeCSSPlugin as PluginCreator<UserDefinedOptions>)({
+        purgeCSSPlugin({
           content: [`${__dirname}/fixtures/src/${file}/${file}.html`],
           fontFace: true,
           keyframes: true,
@@ -43,7 +42,7 @@ describe("Purgecss postcss plugin", () => {
         .mockReturnValue([`${__dirname}/fixtures/src/${file}/${file}.html`]);
 
       postcss([
-        (purgeCSSPlugin as PluginCreator<UserDefinedOptions>)({
+        purgeCSSPlugin({
           contentFunction,
           fontFace: true,
           keyframes: true,
@@ -68,7 +67,7 @@ describe("Purgecss postcss plugin", () => {
       .readFileSync(`${__dirname}/fixtures/expected/simple.css`)
       .toString();
     postcss([
-      (purgeCSSPlugin as PluginCreator<UserDefinedOptions>)({
+      purgeCSSPlugin({
         content: [`${__dirname}/fixtures/src/simple/simple.html`],
         rejected: true,
       }),

packages/postcss-purgecss/src/index.ts

@@ -1,4 +1,85 @@
-import postcss from "postcss";
-import { createPurgeCSSPlugin } from "./postCSSPurgeCSS";
+import { Helpers, PluginCreator, Root } from "postcss";
 
-export default createPurgeCSSPlugin(postcss);
+import PurgeCSS, {
+  defaultOptions,
+  mergeExtractorSelectors,
+  standardizeSafelist,
+} from "purgecss";
+
+import { RawContent, UserDefinedOptions } from "./types";
+
+const PLUGIN_NAME = "postcss-purgecss";
+
+async function purgeCSS(
+  opts: UserDefinedOptions,
+  root: Root,
+  { result }: Helpers
+): Promise<void> {
+  const purgeCSS = new PurgeCSS();
+  const options = {
+    ...defaultOptions,
+    ...opts,
+    safelist: standardizeSafelist(opts?.safelist),
+  };
+
+  if (opts && typeof opts.contentFunction === "function") {
+    options.content = opts.contentFunction(
+      (root.source && root.source.input.file) || ""
+    );
+  }
+
+  purgeCSS.options = options;
+
+  const { content, extractors } = options;
+
+  const fileFormatContents = content.filter(
+    (o) => typeof o === "string"
+  ) as string[];
+  const rawFormatContents = content.filter(
+    (o) => typeof o === "object"
+  ) as RawContent[];
+
+  const cssFileSelectors = await purgeCSS.extractSelectorsFromFiles(
+    fileFormatContents,
+    extractors
+  );
+  const cssRawSelectors = await purgeCSS.extractSelectorsFromString(
+    rawFormatContents,
+    extractors
+  );
+
+  const selectors = mergeExtractorSelectors(cssFileSelectors, cssRawSelectors);
+
+  //purge unused selectors
+  purgeCSS.walkThroughCSS(root, selectors);
+
+  if (purgeCSS.options.fontFace) purgeCSS.removeUnusedFontFaces();
+  if (purgeCSS.options.keyframes) purgeCSS.removeUnusedKeyframes();
+  if (purgeCSS.options.variables) purgeCSS.removeUnusedCSSVariables();
+
+  if (purgeCSS.options.rejected && purgeCSS.selectorsRemoved.size > 0) {
+    result.messages.push({
+      type: "purgecss",
+      plugin: "postcss-purgecss",
+      text: `purging ${purgeCSS.selectorsRemoved.size} selectors:
+          ${Array.from(purgeCSS.selectorsRemoved)
+            .map((selector) => selector.trim())
+            .join("\n  ")}`,
+    });
+    purgeCSS.selectorsRemoved.clear();
+  }
+}
+
+const purgeCSSPlugin: PluginCreator<UserDefinedOptions> = function (opts) {
+  if (typeof opts === "undefined")
+    throw new Error("PurgeCSS plugin does not have the correct options");
+  return {
+    postcssPlugin: PLUGIN_NAME,
+    Once(root, helpers) {
+      return purgeCSS(opts, root, helpers);
+    },
+  };
+};
+purgeCSSPlugin.postcss = true;
+
+export default purgeCSSPlugin;

packages/postcss-purgecss/src/types/index.ts

@@ -3,9 +3,6 @@ import {
   StringRegExpArray,
 } from "../../../purgecss/src/types/index";
 
-import postCSS7 from "postcss7";
-import * as postCSS8 from "postcss";
-
 export interface RawContent<T = string> {
   extension: string;
   raw: T;
@@ -34,8 +31,3 @@ export interface UserDefinedOptions {
   safelist?: UserDefinedSafelist;
   blocklist?: StringRegExpArray;
 }
-
-export type PostCSSv7 = typeof postCSS7;
-export type PostCSSv8 = typeof postCSS8.default;
-
-export type PostCSSVersions = PostCSSv8 | PostCSSv7;