feat: support the pathinfo option (#783)

src/index.js

@@ -984,10 +984,20 @@ class MiniCssExtractPlugin {
       compiler.webpack.sources;
     const source = new ConcatSource();
     const externalsSource = new ConcatSource();
+    const includePathinfo = compilation.outputOptions.pathinfo;
 
     for (const m of usedModules) {
       let content = m.content.toString();
 
+      if (includePathinfo) {
+        // From https://github.com/webpack/webpack/blob/29eff8a74ecc2f87517b627dee451c2af9ed3f3f/lib/ModuleInfoHeaderPlugin.js#L191-L194
+        const req = m.readableIdentifier(requestShortener);
+        const reqStr = req.replace(/\*\//g, "*_/");
+        const reqStrStar = "*".repeat(reqStr.length);
+        const headerStr = `/*!****${reqStrStar}****!*\\\n  !*** ${reqStr} ***!\n  \\****${reqStrStar}****/\n`;
+        content = headerStr + content;
+      }
+
       if (/^@import url/.test(content)) {
         // HACK for IE
         // http://stackoverflow.com/a/14676665/1458162

test/pathinfo.test.js

@@ -0,0 +1,57 @@
+import path from "path";
+
+import MiniCssExtractPlugin from "../src/cjs";
+
+import { compile, getCompiler } from "./helpers/index";
+
+describe("pathinfo option", () => {
+  it(`should insert pathinfo`, async () => {
+    const compiler = getCompiler(
+      "esm.js",
+      {},
+      {
+        mode: "none",
+        output: {
+          pathinfo: true,
+          path: path.resolve(__dirname, "../outputs"),
+        },
+        plugins: [
+          new MiniCssExtractPlugin({
+            filename: "[name].css",
+          }),
+        ],
+      }
+    );
+    const stats = await compile(compiler);
+    const fs = stats.compilation.compiler.outputFileSystem;
+    const extractedCss = fs
+      .readFileSync(path.resolve(__dirname, "../outputs/main.css"))
+      .toString();
+
+    expect(extractedCss).toMatch("./simple.css");
+  });
+  it(`should not insert pathinfo`, async () => {
+    const compiler = getCompiler(
+      "esm.js",
+      {},
+      {
+        mode: "none",
+        output: {
+          path: path.resolve(__dirname, "../outputs"),
+        },
+        plugins: [
+          new MiniCssExtractPlugin({
+            filename: "[name].css",
+          }),
+        ],
+      }
+    );
+    const stats = await compile(compiler);
+    const fs = stats.compilation.compiler.outputFileSystem;
+    const extractedCss = fs
+      .readFileSync(path.resolve(__dirname, "../outputs/main.css"))
+      .toString();
+
+    expect(extractedCss).not.toMatch("./simple.css");
+  });
+});