Restore the URL when POP transitions are canceled

[remix-run]

Restore the URL when POP transitions are canceled

[michalkvasnicak]

Maybe BrowserHistory and HashHistory should be "children" of MemoryHistory?

[mjackson]

As of right now even MemoryHistory isn't able to pull this off. What we're missing is a way to get the "current" index after a POP.

[michalkvasnicak]

I think we need to track a previous location in go() and pushState() calls then pass the previous location to cancelTransition() call together with location we are on. Something like cancelTransition(previous, current).

We are now tracking pendingLocation in transitionTo() but I think we can't use it as previous location to cancelTransition() call because previous and current will be always the same.

In the MemoryHistory it doesn't matter because it isn't listening to POP events and can be modified only using the go(), goBack(), goForward(), replaceState() and pushState() methods. In this case transition will wait for confirmation.

But maybe I am wrong.

[michalkvasnicak]

Another question is, what will happen if user won't use window.confirm but some sort of a modal window that will be nonblocking and pushes back button during a confirmation of previous transition?

1. A
2. B
3. C
4. go back
5. I am on the C but app is asking me for a confirmation and I push back button again
6. I am on B and I confirm previous confirmation and I will be redirected to C?

[michalkvasnicak]

Maybe we should not call transitionTo() if there is any pending transition?

[michalkvasnicak]

Im DOM histories we should track previous and current location in onpopstate/hashchange handlers and pushState() only.

[michalkvasnicak]

@mjackson what do you think about this?

[mjackson]

I think we need to track a previous location in go() and pushState() calls

This will not work immediately after a refresh. Imagine the user comes to the site, navigates from A => B => C and then refreshes the page. At that point, we'd like to know that we have a current value of 2 (assuming a 0-based index).

what will happen if user won't use window.confirm but some sort of a modal window that will be nonblocking and pushes back button during a confirmation of previous transition?

Currently, there is an invariant that prevents this from happening. However, in the situation you described this obviously isn't ideal. I think the right thing to do in that case would be for the user to detect the second transition, remove the modal, and proceed with the latter transition.