History Blocking: Fix loop rendering and usePrompt

[develra]

Note: This should target #9709 - but the implementation changed drastically after 3545cdc - I reviewed the changes and pulled in the bits that still work well with the previous implementation.

This PR includes two major fixes for History Blocking that I needed to be able to continue with our React Router migration. Feel free to take them whole-sale or just pick out the pieces you like. I will say the usePrompt logic took me 4/5 days of iterating and thinking hard about the various scenarios. I tried to comment the code well, but let me know if you have any additional questions.

Here is the behavior usePrompt ended up with - I think it's the best I could do with my approach. To reiterate the issues for what happens if you close a previous prompt with a new back-button click:

Chrome: closes the prompt and triggers the 'shouldBlock' conditional case (window.confirm is false) BUT if it triggers another navigation that event gets dropped on the floor as there is a navigation from the back-button pending.

Safari: closes the prompt and triggers the 'shouldBlock' conditional case (same as chrome), BUT if it triggers another navigation that event gets queued and handled in addition to the navigation event from the back-button.

Firefox: stacks the prompts on top of each other and keeps previous prompts suspended. As the user clicks 'OK' or 'Cancel, the correct response is queued and then all prompts resolve when the final one closes, all navigation triggered seem to happen.

FWIW I think Chrome is the most 'buggy' implementation as it calls a function and drops it on the floor with no error or warning. Both Safari and Firefox have reasonable implementations IMO.

prompt state	Chrome	Firefox	Safari
single prompt accepted	works as expected	works as expected	works as expected
single prompt rejected	works as expected	works as expected	works as expected
multi prompt accepted	will cancel instead	works as expected if user clicks OK on all prompts, else cancel	URL is wrong until user clicks OK and then navigates to the right place
multi prompt rejected	works as expected	works as expected	works as expected

Please pull this and play around with it. AFAICT everything is working as it should, but I could easily have missed something. I think if we do end up taking this whole-sale, it would make sense to mark usePrompt and useBlocker as unstable for the first release to work out an kinks.

Lemme know if you have any questions - I'm both here and on Discord,
Develra

[changeset-bot]

🦋 Changeset detected

Latest commit: a40985c

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 5 packages

Name	Type
@remix-run/router	Minor
react-router	Patch
react-router-dom	Patch
react-router-dom-v5-compat	Patch
react-router-native	Patch

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[chaance]

@develra and I discussed one-off already, but sharing here for anyone watching. We're closing this in favor of #9709 and plan on taking a different approach. We are not going to export usePrompt, but rather rely on useBlocker being the low-level hook needed to implement prompt behavior in userland.