[guest os booting]fix bootmenu msg

[zhentang-tz]

update the check_prompt for ovmf cases to make them compatible with both the old and new versions

Summary by CodeRabbit

Release Notes

• Bug Fixes
  • Enhanced boot menu detection to support multiple boot entry types and applications instead of fixed configurations
  • Strengthened validation of boot menu configuration parameters for improved reliability

[coderabbitai]

Walkthrough

The changes update boot menu validation logic in test configurations and source code. A configuration file modifies the boot menu prompt pattern from matching a specific boot entry ("Boot0000" UiApp) to a more flexible regex pattern that matches Boot entries with dynamic indices and allows either UiApp or BootManagerMenuApp. Simultaneously, the Python source code adds a length validation check, requiring the check_not_prompt list to contain at least 3 elements before executing boot menu output parsing logic.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~8 minutes

🚥 Pre-merge checks | ✅ 3

✅ Passed checks (3 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.
Title check	✅ Passed	The title accurately describes the main change: fixing boot menu messaging for OVMF cases to support compatibility with multiple versions.

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✨ Finishing touches

• 📝 Generate docstrings

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Post copyable unit tests in a comment

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[zhentang-tz]

Test name
Duration
Status
bootmenu.by_ovmf.positive_test.timeout_6000 1 min 4 sec Fixed
bootmenu.by_ovmf.positive_test.timeout_65535 2 min 47 sec Fixed
bootmenu.by_seabios.positive_test.timeout_6000 41 sec Fixed
bootmenu.by_seabios.positive_test.timeout_65535 1 min 37 sec Fixed

[meinaLi]

I'm curious why we need to have the condition len(check_not_prompt) >= 3. I found in cfg file it only has one check_not_prompt with check_not_prompt = LOADPARM=.2,s390-ccw Enumerated Boot Menu,.*Linux version.

[zhentang-tz]

The code hardcodes access to the 3rd element (check_not_prompt[2]). If the config is empty or missing, .split(",") returns [''] (length 1), causing the IndexError I observed. Since s390 is not our focus here, I added this condition as a non-intrusive way to bypass the crash in other variants. It ensures the script only enters the s390-specific exclusion logic when all required markers are provided.