test: add example (#828)

Author: alexander-akait

test/cases/split-chunks-no-vendor/expected/bundle.css

@@ -0,0 +1,13 @@
+/* This could be bootstrap.css */
+body {
+  background: green;
+}
+
+body {
+  background: red;
+}
+
+.async {
+  color: red;
+}
+

test/cases/split-chunks-no-vendor/index.js

@@ -0,0 +1,8 @@
+// eslint-disable-next-line import/no-extraneous-dependencies
+import "bootstrap/bootstrap.css";
+import "./style.css";
+
+// eslint-disable-next-line import/first
+import "package/index";
+
+import("other-css/other.css");

test/cases/split-chunks-no-vendor/node_modules/bootstrap/bootstrap.css

@@ -0,0 +1,3 @@
+body {
+  background: red;
+}

test/cases/split-chunks-no-vendor/node_modules/other-css/other.css

@@ -0,0 +1,40 @@
+import Self from "../../../src";
+
+module.exports = {
+  entry: "./index.js",
+  module: {
+    rules: [
+      {
+        test: /\.css$/,
+        use: [Self.loader, "css-loader"],
+      },
+    ],
+  },
+  optimization: {
+    splitChunks: {
+      chunks: "all",
+      cacheGroups: {
+        default: false,
+        vendors: false,
+        vendor: {
+          test: /[\\/]node_modules[\\/]/,
+          name: "vendor",
+          chunks: "all",
+          enforce: true,
+        },
+        styles: {
+          name: "bundle",
+          type: "css/mini-extract",
+          chunks: "all",
+          priority: 100,
+          enforce: true,
+        },
+      },
+    },
+  },
+  plugins: [
+    new Self({
+      filename: "[name].css",
+    }),
+  ],
+};