Support strict type checking

[bjoluc]

I transitioned the whole project to strict type checking including noImplicitAny, which made me aware of a problem: The WrappedApp's constructor didn't pass the ctx to initStore. In fact, ctx was declared optional for initStore, but required by the MakeStoreOptions definition. This is now fixed.

Other notable changes:

• Update the demo app.tsx to drop the deprecated NextJSAppProps
• Add missing @types/react-test-renderer dev dependency

[bjoluc]

Also, regarding the "nasty hackery" in the client-side tests: Jest supports a jsdom environment, which we could use to get a real window object without hacking. Only requirement: Server and client tests have to be in separate files, since the Jest environment can only be set on a per-file basis. What do you think?

[bjoluc]

Another unrelated (and rather unimportant) thing I noticed: ESLint seems to ignore the .prettierrc configuration, making it throw errors for missing trailing commas. However, the commas are removed on-purpose by the esbenp.prettier-vscode plugin according to .prettierrc. In the end, Husky does the job via eslint --fix and makes eslint happy again. @kirill-konshin Do you think this is worth a fix?

[kirill-konshin]

Very good job! The only issue is the props part.

[kirill-konshin]

Technically since the repo is managed by ESLint, not prettier, you should not run any pure prettier plugins. I'm pushing a fix to make eslint to use prettier config more explicitly. Looks like something changed over time.

[kirill-konshin]

Also, regarding the "nasty hackery" in the client-side tests: Jest supports a jsdom environment, which we could use to get a real window object without hacking. Only requirement: Server and client tests have to be in separate files, since the Jest environment can only be set on a per-file basis. What do you think?

No objections. I'm pushing this now too. You will have to rebase your fork due to conflict.

[kirill-konshin]

Very good job, thank you. Please rebase your fork since there are changes in fix-ts-typings that you are re-implementing.

Also I think we need to update readme with TS-friendly examples. We can do it in separate PR though.

I will release a new major version once we're done here.

[bjoluc]

Ok, I will create a separate readme PR after this, also tackling #170. Thanks for your time!

[kirill-konshin]

Merged. Thank you for your contribution. I will polish things here and there and release a new version soon. And separate kudos for answering questions in issues.

[bjoluc]

You're welcome!