Link to issue number:

Fix up of #12984

Summary of the issue:

Backwards compatibility for the following code was broken in 2021.3 beta.

from gui import isInMessageBox

Note: this code creates a copy of the value of isInMessageBox, and as such, was only accurate if it was being imported when it was being checked. Importing like this also prevents gui.isInMessageBox from being updated:

from gui import isInMessageBox
isInMessageBox = False  # this doesn't update gui.isInMessageBox

Description of how this pull request fixes the issue:

Creates a isInMessageBox that is updated by isInMessageBox.
Note that while from gui import isInMessageBox can run without error now, using or updating the variable will not work as expected, nor has it ever worked properly.

Testing strategy:

Manual testing with 2021.2 and this PR

1. Open the NVDA python console
2. With no other NVDA dialogs open, run this code snippet, confirm the result is False, False

   from gui import isInMessageBox
   print(isInMessageBox)
   
   import gui
   print(gui.isInMessageBox)

3. Open the About dialog, run the code snippet, confirm the result is False, True, True

   print(isInMessageBox)
   
   from gui import isInMessageBox
   print(isInMessageBox)
   
   import gui
   print(gui.isInMessageBox)

4. With no other NVDA dialogs open, run this code snippet, confirm the result is False, True

   from gui import isInMessageBox
   isInMessageBox = True
   
   import gui
   print(gui.isInMessageBox)
   
   gui.isInMessageBox = True
   print(gui.isInMessageBox)

Known issues with pull request:

None

Change log entries:

None needed, fixes regression

Code Review Checklist:

• Pull Request description:
  • description is up to date
  • change log entries
• Testing:
  • Unit tests
  • System (end to end) tests
  • Manual testing
• API is compatible with existing add-ons.
• Documentation:
  • User Documentation
  • Developer / Technical Documentation
  • Context sensitive help for GUI changes
• UX of all users considered:
  • Speech
  • Braille
  • Low Vision
  • Different web browsers
  • Localization in other languages / culture than English