[go_router] Allow any number of the same page on the stack

[koji-1009]

Restore the function to push the same page multiple times, which was supported in v3.1.1.

Fixes flutter/flutter#107045

Refs

• https://github.com/flutter/packages/blob/go_router-v3.1.1/packages/go_router/lib/src/go_router_delegate.dart#L264
• csells/go_router@800d29a#diff-a894fc0967a6e4235d9deb900b9454f67082e9836146c1024f863bf73f578cb7R234

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[chunhtai]

I started to think support the push in the declarative way may be the wrong decision. as soon as a page is pushed to the stack, the stack will not be in sync with the url any more.
In this particular use case where you want to push the same page, does it make more sense to be a pageless route? that is, pushing use the Navigator.of(context). The difference is the pageless route will belong to the top most page route and will be move/remove with that page route

[koji-1009]

On GitHub, after opening the top of the repository, you can open the list of pull requests and open the pull request details.
Also, using this PR as an example, clicking on the flutter:main branch link will open the top of the repository. A use case would be to implement this process in Flutter Web/Android/iOS.
At this point, we have the choice between context.go and context.push. The problem in this case is not go but push, so we want to back to the last open page.

---

If we don't want the delegate to have a Map, why not change the process so that the pageKey has a random suffix (e.g. UUID). Having state.pageKey as the Route key is the preferred method for most applications that use go_router.

[chunhtai]

LGTM, just some nitpicks

[chunhtai]

can you do an await tester.pumpAndSettle() in between every push to verify it does not crash?

[koji-1009]

Thanks for the review, I fixed it in 2ee5fd6.

[prince-kumar]

LGTM

[chunhtai]

not sure why the check failed, can you rebase and try again?

[koji-1009]

flutter/plugins#6146

[stuartmorgan-g]

This change must not be landed until the underlying problem with 4.2.1 is fixed, or it will re-break everyone that was broken by 4.2.1 (since it'll publish a new version with the same bug).

@johnpryan @chunhtai please don't approve any more go_router PRs until the fix for the breakage is fixed, to avoid any accidents.

[stuartmorgan-g]

Adding a request changes until the above has been resolved to ensure this doesn't accidentally land.

The regression has been resolved