Refactor to ESM

[cossssmin]

@Scrum I'd like to work on a new major release for posthtml-expressions that would include:

• refactoring code to ESM-only
• require Node.js 18+
• migrate tests to use Vitest
• switch style linting to eslint
• add type definitions

Please let me know if you're OK with this and I'll start work on the PR. Thanks!

[Scrum]

@cossssmin I'm glad you can do it, thank you!

[cossssmin]

Thanks, will get started and let you know when it's ready for review.

Did you have any plans for it? We could add them in this refactor.

[Scrum]

Did you have any plans for it? We could add them in this refactor.

There were a couple of ideas:

• use tsup or vitejs as a collector,
• use the general prettier rules,
• use the general rules for typescript,
• general rules for vscode/idea,
• configure ci/cd (install, test, optional build, publish by tag or after the merge),
• consider turborepo

[cossssmin]

OK, I'd start on it and when I'm done you could add those maybe? Or do you prefer we launch a major version first and then add those ideas?

[Scrum]

OK, I'd start on it and when I'm done you could add those maybe? Or do you prefer we launch a major version first and then add those ideas?

Rather, as you prefer, these are the best ideas)

[cossssmin]

Could we take this opportunity to think about what options we have for replacing node:vm so that the plugin could be used in a browser environment? Would Function work?

This would be a game-changer for frameworks like Maizzle, you could run the entire PostHTML build chain right in the browser, no serverless/Lambdas needed.

[Scrum]

It is necessary to explore this direction, in the first approximation it looks like vm-browserify

[cossssmin]

I was looking at the Alpine.js evaluator the other day, maybe something like this would be enough?

https://github.com/alpinejs/alpine/blob/main/packages/alpinejs/src/evaluator.js

Didn't know about vm-browserify, looks like it's very popular but it's only for the browser and it creates an <iframe> for each code execution which leads to other issues like web workers not working.

[cossssmin]

This also looks interesting, it uses @babel/parser to parse expressions:

https://github.com/william-yz/ts-expression-evaluator

[cossssmin]

Another idea would be to create an interface and allow for various templating engine adapters. For example, there's LiquidJS that people could use instead of the default engine.