IssueTracker

apologies, i meant "navigate(To...)"

Yep, it appears that navigateUp() returns true, even when nothing visually changes on the screen. This seems to be caused by popBackStack(), which is always returning true even when popping the root Fragment.

Project: platform/frameworks/support
Branch: androidx-master-dev

commit 77f6f126b51ef6c880368ed5b4ac900c7b187165
Author: Ian Lake <ilake@google.com>
Date:   Wed Feb 06 10:03:44 2019

    Fix popBackStack logic when popping the root destination
   
    popBackStack() and by extension navigateUp() should
    only return true if the user was successfully navigated
    to a new destination. In cases where the entire stack
    was popped, the methods should return false so that
    additional logic, such as finishing the activity, can
    be employed.
   
    This fixes a regression introduced in
    https://issuetracker.google.com/issues/123552990
   
    Test: updated tests
    BUG: 123933201
    Change-Id: I756481f14b2c7d9b8f401bea05c4dbd16d28f614

M       navigation/runtime/src/androidTest/java/androidx/navigation/NavControllerTest.kt
M       navigation/runtime/src/main/java/androidx/navigation/NavController.java

https://android-review.googlesource.com/896574
https://goto.google.com/android-sha1/77f6f126b51ef6c880368ed5b4ac900c7b187165

This is fixed and will be available in Navigation 1.0.0-beta02.

Seeing that the `launchWhenX` APIs will soon be deprecated, maybe it would a good idea to update the documentation at: https://developer.android.com/topic/libraries/architecture/coroutines#suspend.
Cause it might get confusing for people finding that documentation page and then being told that it's gonna be deprecated.