feat: add support for Visual Studio 2026

[keelbismark]

This pull request introduces initial support for the upcoming Visual Studio 2026 (internal version 18.0).

The key changes include:

• Version Detection: Added '2026' and version '18.0' to the version maps in SelectVisualStudioVersion and _DetectVisualStudioVersions. This allows GYP to correctly identify VS 2026 installations.
• Version Creation: Included a new VisualStudioVersion definition for '2026' in the _CreateVersion function.
• Toolset Update: Set the default_toolset to v145. This aligns with the toolset version observed in the Visual Studio 2026 Insider Preview builds, resolving potential MSB8020 errors for users on the latest previews.

These changes enable developers using early versions of Visual Studio 2026 to generate and build projects with GYP seamlessly.

[keelbismark]

Hi team,

This is my first PR here! I've tested the change successfully on the VS 2026 Insider Preview locally.

I was unable to run the full test suite on Windows due to the known os.uname() platform issue in the test framework.

Thanks for adding the Windows label! I'm ready for the review process and for the CI/CD workflows to be approved and run.

[keelbismark]

Follow-up: Just wanted to confirm that I was able to successfully run the full unit test suite (29 passed, 5 skipped) after some local environment setup. The code is stable and passes all existing tests.

[cclauss]

Can one or more tests be added to verify that this performs the expected actions?

Also, Error: pylib/gyp/MSVSVersion.py:553:89: E501 Line too long (95 > 88)

[keelbismark]

Hi cclauss, thanks for the review!

I've fixed the E501 line length issue in a new commit.

Regarding testing: I've verified this change performs the expected actions by successfully generating and compiling the Breakpad project using the Ninja backend with VS 2026. The change also passes the existing unit test suite locally (29 passed, 5 skipped).

Could you please approve the workflows so the CI can run the full test matrix? Thanks!

[StefanStojanovic]

Thanks for this work. I see you have a PR with same changes in node--gyp repo. I assume the idea is to land this one, close the other one, and then pull it in as a gyp-next update. Correct?

[keelbismark]

Yes, that's correct

[StefanStojanovic]

OK, the changes seem reasonable. Simply enabling a new VS version.

One thing that needs to be done after this lands in node-gyp is to add tests there for the new VS version, eg. look for VS2026 by version number, VSSetup: VS2026 with C++ workload, etc.

[keelbismark]

Understood. Tests for VS 2026 in node-gyp will be added after the gyp-next update

[cclauss]

RSLGTM