Open Radar

 
Summary:
The TouchID alert sometimes does not disappear before the reply block of LAContext's evaluatePolicy:localizedReason:reply: executes.

Steps to Reproduce:
1. Make sure the app, in this case PasscodeTest, is not running in the background.
2. Tap to open the PasscodeTest app while having a finger on the TouchID sensor.
3. Observe that the label changes from "Evaluating..." to "Unlocked" and the background screen turns green, but the TouchID alert remains on the screen.

Expected Results:
TouchID alert dialog should dismiss before the reply block begins executing.

Actual Results:
The TouchID alert dialog remains on the screen after the reply block has executed. When you tap "Enter Password" or "Cancel," the TouchID alert disappears, but the screen becomes unresponsive to touches and the home button does not close the app. In order to get the iPhone to be responsive again, you have to press the power button to turn off the screen and then unlock the phone.

Version:
iOS 8.2 (12D436)

Notes:
Attached is a video of me demonstrating the reproducible steps, along with the results described above. Also attached is a sample project named PasscodeTest that I use in the video. Note, I found this issue significantly difficult to reproduce with the debugger.

Configuration:
iPhone 6 Plus 16GB AT&T, using WIFI