fix: handle undefined prevroute during createStore/firstRoute

[stevelr]

Inside createStore, during execution of firstRoute(), req.prevRoute is undefined, so when the middleware chain gets to call("beforeLeave", { prev=true }), route becomes undefined, and it crashes with "no beforeLeave on undefined".
I've been using rudy for over a month without running into this, so there is probably another issue in my code or build process, but this change made it work for me.

[hedgepigdaniel]

Excellent, thanks!

rudy/packages/rudy/src/core/createRequest.js

Lines 59 to 60 in 3492cac

	const prevRoute = kind === 'init' ? routes[prev.type] || {} : routes[type]

It looks like prevRoute might be {} or undefined - undefined in the case that kind !== 'init' and the current action type is not in routesMap (e.g. its NOT_FOUND and you haven't defined that). Perhaps before prevRoute was ending up as {}, and that was enough to avoid the crash?

I prefer the idea that if there is no previous route, prevRoute is undefined/null rather than an empty object (since anyone referring to it should be accounting for the concept being potentially invalid, e.g. on the first route, or from a 404). I think we should make that consistent, and add some unit tests to cover

• The creation of the request so that it returns the correct prevRoute
• The call middleware so that it responds correctly to different values of prevRoute

If you wanted to work on that there's some unit tests here you can use as an example: 77ad467

Otherwise I'll aim to do it soon.

[ScriptedAlchemy]

awesome find

[ScriptedAlchemy]

@hedgepigdaniel lets catch up I think it's time i get some skin in this game with you

[hedgepigdaniel]

@stevelr Any chance you can create a simple reproduction of this?

I'm struggling to understand how and why route could be undefined in that case.

[hedgepigdaniel]

Some background:

• formatRoutes is called in createRouter which should be before any actions are dispatched, and it adds a route for NOT_FOUND in case that's the trigger.
• Where prevRoute is set in createRequest, const prevRoute = kind === 'init' ? routes[prev.type] || {} : routes[type] even if routes[prev.type] is undefined, prevRoute would still end up as {}.

[ScriptedAlchemy]

@stevelr bump on reproduction

[stevelr]

I'm the last one mentioned here so I hope this wasn't blocked on me. I'm not a rudy user and I don't know if this is even still relevant. I shouldn't be on the decision chain for this.