[pmeems]

Expand the ActiveX test host checks for the final plan phase. The new checks use the existing COM interfaces and preserve the JSON report and timeout behavior.

• Cover multiple loads, stable IDs, navigation, resizing, clearing and reloading, invalid inputs, empty-map behavior, and GDI/OpenGL rendering paths.
• Add a README for building and using the manual and automated host. Update the root README and testing guide.
• Record the verified late-bound COM error mapping in project testing memory.

Validation: Debug x64 and Win32 builds completed with zero warnings. The origin/development Debug x64 baseline also had zero warnings. Core tests passed (268, with 1 opt-in network test skipped); ActiveX tests passed (46, with 2 opt-in tests skipped). All 26 host checks passed on x64 and Win32. The manual host opened and closed successfully.

The hosted checks require an interactive Windows desktop and are not part of headless CI.

[Julian-MW]

Code review summary

Reviewed all 5 changed files, including the complete MainForm.cs changes, the host README, testing documentation, root README, and testing memory. Checked the changes against the repository guidance and the ActiveX host/COM behavior.

Findings: No actionable correctness, reliability, or maintainability issues identified in the changed code.

Validation: The PR's GitHub Actions build (x64, Debug) job completed successfully, including its build and test steps. The interactive Windows ActiveX host checks are not part of CI; I did not independently run those desktop-only checks, so the manual x64/Win32 results in the PR description remain author-reported.

Recommendation: Looks good to merge, subject to the usual human review of the reported interactive-host validation.

Risk: Low based on the diff reviewed.

[Copilot]

🟢 Approval recommended

No active review issues block approval of the expanded ActiveX host checks and documentation.

No open issues 🎉

What changed in this PR

Expands the WinForms ActiveX test host’s automated checks using existing COM interfaces, while preserving JSON reporting and timeout behavior.

Changes:

• Adds checks for multiple datasets, stable layer IDs, navigation, resizing, clearing and reloading, invalid inputs, and empty-map behavior.
• Extends rendering checks to request OpenGL while allowing GDI fallback.
• Documents manual and automated host usage and records late-bound COM error mapping.

Hosted checks require an interactive Windows desktop and remain outside headless CI. Builds and tests were not rerun during this review.

File	Description
samples/​CSharp/​ActiveXTestHost/​README.md	Adds build, usage, automated-check, and limitation documentation.
samples/​CSharp/​ActiveXTestHost/​MainForm.cs	Expands automated checks and adds shared assertion helpers.
README.md	Adds the ActiveX test host to the repository layout.
docs/​TESTING.md	Updates hosted-check coverage and links to host instructions.
.ai/​memory/​testing/​testing.md	Records the late-bound invalid-layer-ID exception mapping.

_{Review effort: Balanced}