[BUG] PopRootAndTick in ViewStackServiceBase leaves behind the wrong viewmodel

[limefrogyank]

[BUG] PopRootAndTick in ViewStackServiceBase leaves behind the wrong viewmodel

[limefrogyank]

I don’t have easy access to testing on iOS so I don’t know. *Edited the above paragraph for clarity* I've only tested on Android...

[RLittlesII]

That means your code somehow made it to the master branch, as my branch is cut from the most recent master.

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[RLittlesII]

@limefrogyank Thanks for reporting this. I had some other issues that I resolved on Xamarin.iOS around PopToRoot not too long ago. I will look into this and see if we can find a resolution.
The thought behind removing is to try and leave a ViewModel on the stack.

Is this really specific to Xamarin.Forms Android? I will try and reproduce it on iOS to be safe, as that seems an odd side effect.

[RLittlesII]

@limefrogyank So I am trying to reproduce this, but no matter how many Red Pages I push on iOS, I don't see the problem. I have a branch GH189 where I am reproducing this. Can you verify that this code still produces an error on your side? I am moving to test Android now, just want to be sure my reproduction is correct.

[limefrogyank]

Oh, you've got the changes I made already put into your branch. The original code for PopRootAndTick was this:

IImmutableList<T> poppedStack = ImmutableList<T>.Empty;

            if (stackSubject?.Value == null || !stackSubject.Value.Any())
            {
                throw new InvalidOperationException("Stack is empty.");
            }

            stackSubject
                .Take(stackSubject.Value.Count - 1)
                .Where(stack => stack != null)
                .Subscribe(stack => poppedStack = stack.RemoveRange(stack.IndexOf(stack[0]), stack.Count - 1));

            stackSubject.OnNext(poppedStack);

Yeah, that's the bad code...

[RLittlesII]

@limefrogyank Can you verify master is fixed? Then I would argue we can close this and attach it to the PR that solved the problem.

[limefrogyank]

This works fine for me. Sorry to slip that in unnoticed.

Fixed with dc23331

Right?

[RLittlesII]

Yes. No worries about it. It was a big PR with a lot of files changed. Appreciate the contribution!