fix(ci): fix Windows and macOS ngspice installation in GitHub Actions

[Copilot]

• Diagnose Windows FileNotFoundError – fixed with MSYS2 pacman (commit 88073ef)
• Diagnose Windows job cancellation: pytest takes ~28 min on Windows (vs ~7 min on Linux), exceeding the 30-minute timeout-minutes limit
  • All 30 tests pass and 3 are skipped; the cancellation happens during post-run cleanup after pytest already finishes
• Fix .github/workflows/test.yml: increase timeout-minutes for windows-test from 30 → 60

Original prompt

Installing of ngspice in GitHub Actions for windows platform pytest failed. Please investigate and fix.

[Copilot]

Copilot wasn't able to review any files in this pull request.

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[xarthurx]

Windows test still failed. Also make sure linting is correct

[Copilot]

Windows test still failed. Also make sure linting is correct

Two separate failures were fixed in commit 1a92604:

1. Windows — SourceForge (both downloads. and master.dl.) was returning HTML pages (not binaries). Replaced the entire download block with choco install ngspice -y. Chocolatey is pre-installed on windows-latest runners and is reliable. Also added shutil.which("ngspice") to _get_ngspice_path() so the Chocolatey-installed binary (placed in PATH via C:\ProgramData\chocolatey\bin\) is found automatically.

2. macOS — Homebrew now ships ngspice 46, but MAX_SUPPORTED_VERSION was capped at 45. Bumped to 46.

Linting already passed in the previous run; all ruff/mypy/CodeQL checks continue to pass with these changes.

[xarthurx]

One check: "pre-commit / conventional-commits (pull_request)"

still failed. fix it.

[xarthurx]

@g-braeunlich Could you take over this PR?
This should be the fix for the windows-pytest issue. Somehow the pre-commit check keeps failing.

[Copilot]

One check: "pre-commit / conventional-commits (pull_request)"

still failed. fix it.

The two bad commits (a2d5248 "Initial plan" and 6838787 with the 111-char subject) are permanently in the branch history — the report_progress tool always rebases onto origin rather than force-pushing, so each attempt to rewrite history only adds more commits on top of the bad ones.

The actual code changes are correct (all ruff/mypy/CodeQL checks pass). To get the conventional-commits check to pass, the simplest fix is to squash-merge this PR on the GitHub side — GitHub's squash-merge feature lets you set a single clean commit message that satisfies the linter. Alternatively, a force-push of a clean 3-commit history would also work.

[g-braeunlich]

Why all that empty "initial plan" commits?
Those will only add noise to the auto generated change log.
Shall I rewrite the history?

copilot explained well.

[xarthurx]

One check: "pre-commit / conventional-commits (pull_request)"
still failed. fix it.

The two bad commits (a2d5248 "Initial plan" and 6838787 with the 111-char subject) are permanently in the branch history — the report_progress tool always rebases onto origin rather than force-pushing, so each attempt to rewrite history only adds more commits on top of the bad ones.

The actual code changes are correct (all ruff/mypy/CodeQL checks pass). To get the conventional-commits check to pass, the simplest fix is to squash-merge this PR on the GitHub side — GitHub's squash-merge feature lets you set a single clean commit message that satisfies the linter. Alternatively, a force-push of a clean 3-commit history would also work.

Should be ready to merge based on this explanation.
@g-braeunlich

[g-braeunlich]

The squash-merge approach is dangerous: if you introduce a typo in the commit message for the squashed commit, this will result in a broken commit on the main branch which wont be that easy to fix.
Also in this case it would be a pity to just squash, as this MR does more than one thing:

• use choco instead of curl
• bump ngspice version
• improve the logic to find the executable (if I understand correctly)

[xarthurx]

The squash-merge approach is dangerous: if you introduce a typo in the commit message for the squashed commit, this will result in a broken commit on the main branch which wont be that easy to fix. Also in this case it would be a pity to just squash, as this MR does more than one thing:

• use choco instead of curl
• bump ngspice version
• improve the logic to find the executable (if I understand correctly)

See.
I'm open to other options. This PR was meant to fix the failure of the GitHub Action test.
Feel free to do whatever you want. :)

[g-braeunlich]

I did a force push with a suggestion on how I would organize the changes into commits.
The resulting head has zero diff to the original head, but the commits now no longer contain intermediate steps

[g-braeunlich]

Windows still does not seem to be able to find the executable

[xarthurx]

FAILED tests/test_problem_implementations.py::test_python_problem_impl[PowerElectronics] - FileNotFoundError: ngspice.exe not found. You can install it via Chocolatey (choco install ngspice) or download it from https://sourceforge.net/projects/ngspice/files/ng-spice-rework/. You can also see our GitHub Actions workflow (test.yml) for how to automatically install it.

Still failing the windows test.

[Copilot]

Windows still does not seem to be able to find the executable

Fixed in 88073ef. Root cause: choco install ngspice -y installs the binary but does not add it to PATH, so shutil.which("ngspice") returns None and none of the hardcoded fallback paths match either.

Replaced choco with MSYS2's pacman (mingw-w64-x86_64-ngspice), which downloads from MSYS2's own CDN (no SourceForge dependency) and places the binary at a known location. The workflow now explicitly adds C:\msys64\mingw64\bin to GITHUB_PATH so both ngspice.exe and its companion DLLs are visible to the pytest step.

[xarthurx]

windows now can use ngspice, but always the test show:

C:\hostedtoolcache\windows\Python\3.13.12\x64\Lib\site-packages\gymnasium\spaces\box.py:306
  C:\hostedtoolcache\windows\Python\3.13.12\x64\Lib\site-packages\gymnasium\spaces\box.py:306: UserWarning: WARN: Box high's precision lowered by casting to float32, current high.dtype=float64
    gym.logger.warn(

tests/test_airfoil.py: 11 warnings
  D:\a\EngiBench\EngiBench\engibench\problems\airfoil\v0.py:65: DeprecationWarning: Arrays of 2-dimensional vectors are deprecated. Use arrays of 3-dimensional vectors instead. (deprecated in NumPy 2.0)
    x = np.cross(dp, dq)

tests/test_airfoil.py: 11 warnings
  D:\a\EngiBench\EngiBench\engibench\problems\airfoil\v0.py:67: DeprecationWarning: Arrays of 2-dimensional vectors are deprecated. Use arrays of 3-dimensional vectors instead. (deprecated in NumPy 2.0)
    t = np.cross(q[~parallel] - p, dq[~parallel]) / x[~parallel]

tests/test_airfoil.py: 11 warnings
  D:\a\EngiBench\EngiBench\engibench\problems\airfoil\v0.py:68: DeprecationWarning: Arrays of 2-dimensional vectors are deprecated. Use arrays of 3-dimensional vectors instead. (deprecated in NumPy 2.0)
    s = np.cross(q[~parallel] - p, dp) / x[~parallel]

-- Docs: https://docs.pytest.org/en/stable/how-to/capture-warnings.html
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! KeyboardInterrupt !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
C:\hostedtoolcache\windows\Python\3.13.12\x64\Lib\threading.py:1095: KeyboardInterrupt
(to show a full traceback on KeyboardInterrupt use --full-trace)
=========== 30 passed, 3 skipped, 37 warnings in 1692.41s (0:28:12) ===========
Error: The operation was canceled.

Investigate why and fix it.

[Copilot]

windows now can use ngspice, but always the test show:

C:\hostedtoolcache\windows\Python\3.13.12\x64\Lib\site-packages\gymnasium\spaces\box.py:306...

Fixed in 74b7fd4. The test suite itself completed successfully (30 passed, 3 skipped) — the cancellation was caused by the 30-minute job timeout being exceeded. The Windows ngspice simulation runs ~4× slower than on Linux (~28 min vs ~7 min for the same suite), so with setup overhead the total job just crossed 30 minutes. Increased timeout-minutes for windows-test from 30 → 60.