Add type hints for the (Python) codebase.

[teymour-aldridge]

One thing I think would make it substantially easier to refactor code and catch bugs which aren't possible to catch otherwise. In addition, having types makes it possible to use the wealth of code analysis tools which are out there.
I imagine for the Javascript stuff, Flow or Typescript could be used.
I'd be happy to work on this.

[czlee]

Sure, I'd support seeing type hints added where useful. It'll be a lot of work, of course, so it's fine if the transition is gradual, like a lot of refactoring work we've done on the Tabbycat code base.

[daankoning]

@teymour-aldridge still intend to do this? If not I'd be happy to begin a bit of work on this.

[czlee]

@daankoning Sorry I haven't had a chance to reply sooner. You're welcome to work on this if you're particularly interested in it, but I should say, I think there are much more egregious areas of technical debt in Tabbycat than type hints, examples:

• Our unit test coverage is currently pretty bad.
• There are some classes that have outgrown themselves and need to be refactored for DRY and separation of concerns. (Our tables generators, in files named tables.py, come to mind.)
• Our action logs are a bit ad hoc and not as useful as they could be.
• Things like Rework the preferences module to be more user-friendly #500

Happy to discuss what you're interested in! I just wanted to say it's probably not the most pressing thing on our backlog.

[daankoning]

Oh thats fine too. I'll have a look at some of those as well :)