in memory fs usage in webpack

test.js

    it("does not add translations twice if file is recompiled after change", function (done) {
        var testCase = path.join(__dirname, "../fileChange.js");
        var fs = new MemoryFS();
        fs.mkdirpSync(path.join(__dirname, "../"));
        fs.writeFileSync(testCase, "require('./otherFile.js');\n" +
                                    "i18n.registerTranslation('NEW_USER', 'New user');\n" +
                                    "i18n.registerTranslation('DELETE_USER', 'Delete User');\n" +
                                    "i18n.registerTranslation('WillBeDeleted', 'Delete');");
        fs.writeFileSync(path.join(__dirname, "../otherFile.js"), "i18n.registerTranslation('DELETE_USER', 'Delete User');");

        var options = webpackOptions({
            entry: "./fileChange.js"
        });
        var compiler = webpack(options);
        compiler.inputFileSystem = fs;
        compiler.resolvers.normal.fileSystem = compiler.inputFileSystem;
        compiler.resolvers.context.fileSystem = compiler.inputFileSystem;
        compiler.outputFileSystem = fs;

        var firstRun = true;
        var watching = compiler.watch({}, function (error, stats) {
            "use strict";

            assert.notOk(error, "Failed to compile the assets");

            if (firstRun) {
                assert.deepEqual(stats.compilation.errors, [], "First compilation failed with errors");

                firstRun = false;
                fs.writeFileSync(testCase, "i18n.registerTranslation('NEW_USER', 'Neuer Benutzer');");
                watching.invalidate(); // watch doesn't seem to work with memory fs
            } else {
                assert.deepEqual(stats.compilation.errors, [], "The implementation should not emit duplicate translation errors after recompilation with different text.");

                var translations = JSON.parse(fs.readFileSync(path.join(__dirname, "dist/translations.json")));
                assert.propertyVal(translations, "NEW_USER", "Neuer Benutzer", "Uses the updated translation");
                assert.propertyVal(translations, "DELETE_USER", "Delete User", "Does not delete translations used by other resources");
                assert.notProperty(translations, "WillBeDeleted", "The property is not used by fileChange.js anymore, so we should remove it from the translations.json");

                watching.close(done);
            }
        });
    });
    

Is this still working for you? I'm setting the fs as you are, but it still seems to be trying to resolve modules in memory fs instead of the actual file system