TestMemoryFS.test.js

import path from "path";

import { createFsFromVolume, Volume } from "memfs";
import webpack from "webpack";

const assetsNames = (assets) => assets.map((asset) => asset.name);

describe("TestMemoryFS", () => {
  it("should preserve asset even if not emitted", (done) => {
    const casesDirectory = path.resolve(__dirname, "cases");
    const directoryForCase = path.resolve(
      casesDirectory,
      "publicpath-default-auto"
    );
    // eslint-disable-next-line import/no-dynamic-require, global-require
    const webpackConfig = require(path.resolve(
      directoryForCase,
      "webpack.config.js"
    ));
    const compiler = webpack({
      ...webpackConfig,
      mode: "development",
      context: directoryForCase,
      cache: false,
    });

    compiler.outputFileSystem = createFsFromVolume(new Volume());

    compiler.run((err1, stats1) => {
      if (err1) {
        done(err1);

        return;
      }

      compiler.run((err2, stats2) => {
        if (err2) {
          done(err2);

          return;
        }

        expect(assetsNames(stats1.compilation.getAssets())).toEqual(
          assetsNames(stats2.compilation.getAssets())
        );

        done();
      });
    });
  });
});