Link to issue number:

Based on #15021
Fixes #14978

Summary of the issue:

Downloading and installing an add-on follows these steps:

1. Download and install is triggered by the user
2. Download begins and writes to addonStore/_dl/addonId.download
3. Download completes, and the file is renamed and cached addonStore/_dl/addonId-1.23.nvda-addon
   i. if you change tab here, the add-on state can be lost
4. User exits NVDA add-on store
5. Add-on installation is triggered, add-on is unzipped and written to addons/addonId.pendingInstall
6. User is prompted to restart
7. On restart addons/addonId.pendingInstall is installed to addons/addonId

When changing tabs before exiting the add-on store, the state "download pending install" is lost.

Description of user facing changes

When changing tabs before exiting the add-on store, the state "download pending install" is no longer lost.

Description of development approach

The pending install state check was updated for the add-on store add-on model to include checks for download state.
Add-ons that are downloaded pending install should now be treated as if they are pending install.

The add-on state determiner now returns the correct state for add-ons which are downloaded but yet to start the install process.

Testing strategy:

Test STR described in issue

Known issues with pull request:

N/A

Change log entries:

N/A

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
• Security precautions taken.