MOB-22620: Fix concurrent modification exception during session termination

[prudrabhat]

Description

Problem

notifyTerminationAndRemoveStatusListeners() iterates over all the connection status listeners to notify disconnection and un-registers them. Since the de-registration process involves removing the listeners from the set, iterating over the same list for removal leads to ConcurrentModificationException and not all listeners are notified of the error. This results in the connecting icon spinning forever.
This situation only occurs for terminal errors/ non retryable errors so it does not affect the normal workflow.

Solution

Iterate for de-registration over a copy of the listeners to prevent the exception and propagate the error.

Related Issue

MOB-22620

Motivation and Context

notifyTerminationAndRemoveStatusListeners() iterates over all the connection status listeners to notify disconnection and un-registers them. Since the de-registration process involves removing the listeners from the set, iterating over the same list for removal leads to ConcurrentModificationException and not all listeners are notified of the error. This results in the connecting icon spinning forever.
As a solution, iterate for de-registration over a copy of the listeners to prevent the exception and propagate the error.

How Has This Been Tested?

• Manual tests
• Existing unit tests

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• I have signed the Adobe Open Source CLA.
• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

[praveek]

How about sessionStatusListeners.clear() ?

[prudrabhat]

Yes! Clearing here is better. Will patch.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 71.20%. Comparing base (cb49261) to head (12cd318).
Report is 31 commits behind head on dev-v3.x.

Additional details and impacted files

@@              Coverage Diff               @@
##             dev-v3.x     #147      +/-   ##
==============================================
- Coverage       71.26%   71.20%   -0.06%     
+ Complexity        413      411       -2     
==============================================
  Files              66       66              
  Lines            3274     3271       -3     
  Branches          403      402       -1     
==============================================
- Hits             2333     2329       -4     
- Misses            727      730       +3     
+ Partials          214      212       -2     

Flag	Coverage Δ
android-functional-tests	24.46% <0.00%> (?)
android-unit-tests	51.24% <100.00%> (?)
functional-tests	?
unit-tests	?

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
...ng/mobile/assurance/internal/AssuranceSession.java	81.55% <100.00%> (-0.91%)	⬇️