Webpack 5 update breaks wrapper-webpack-plugin

[bodenloszt]

Hello, guys!

I have a Preact project that uses Webpack 4 as it's bundling utility. I want to update to Webpack 5. I encountered lots of errors and changes that had to be done and right now I am almost at the end of it. But I am currently facing a huge blocker.

The project I work on has a webpack-server.config that uses wrapper-webpack-plugin at one point and it looks like this:

        new WrapperPlugin({
            test: /\.js$/,
            header: `
                exports['setupGlobals'] = function (globals) {
                    var navigator = globals.navigator;
                    var location = globals.location;

                    var render = `,
            footer: `
                return { render: render };
            }`
        })

Later it uses setupGlobals().render() as:

const { html, chunks, http2Links } = serverApp.setupGlobals(getGlobals(ctx)).render(clone(state));

After I upgraded Webpack 4 -> Webpack 5, this Wrapper doesn't work anymore. It returns render as undefined so it can't be called.

The build is working webpack 5.84.0 compiled -> Build done! but when I try to access the app via browser, I get error 500 and this error:

500 TypeError: serverApp.setupGlobals(...).render is not a function

Does anyhow have any idea why this wrapper wouldn't work in Webpack 5? Thanks a bunch!