✨ feat(windows): use SHGetKnownFolderPath API#380
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You'll need to fix the type checker at least 👍
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Fix tox-dev#348 Co-authored-by: moi15moi <moi15moismokerlolilol@gmail.com>
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SHGetKnownFolderPath with default flags (0) verifies that the target folder physically exists, raising FileNotFoundError in sandboxed Windows environments where USERPROFILE points to a directory without AppData\Local. This was a regression introduced in 4.7.0 when PR tox-dev#380 replaced SHGetFolderPathW with SHGetKnownFolderPath. Passing KF_FLAG_DONT_VERIFY (0x00004000) restores the pre-4.7.0 behavior of returning the expected path without existence checks, matching how the old SHGetFolderPathW API worked. Closes tox-dev#421
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SHGetKnownFolderPath with default flags (0) verifies that the target folder physically exists, raising FileNotFoundError in sandboxed Windows environments where USERPROFILE points to a directory without AppData\Local. This was a regression introduced in 4.7.0 when PR tox-dev#380 replaced SHGetFolderPathW with SHGetKnownFolderPath. Passing KF_FLAG_DONT_VERIFY (0x00004000) restores the pre-4.7.0 behavior of returning the expected path without existence checks, matching how the old SHGetFolderPathW API worked. Closes tox-dev#421 Signed-off-by: Bernát Gábor <bgabor8@bloomberg.net>
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SHGetKnownFolderPath with default flags (0) verifies that the target folder physically exists, raising FileNotFoundError in sandboxed Windows environments where USERPROFILE points to a directory without AppData\Local. This was a regression introduced in 4.7.0 when PR tox-dev#380 replaced SHGetFolderPathW with SHGetKnownFolderPath. Passing KF_FLAG_DONT_VERIFY (0x00004000) restores the pre-4.7.0 behavior of returning the expected path without existence checks, matching how the old SHGetFolderPathW API worked. Closes tox-dev#421 Signed-off-by: Bernát Gábor <bgabor8@bloomberg.net>
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* 🐛 fix(windows): pass KF_FLAG_DONT_VERIFY to SHGetKnownFolderPath SHGetKnownFolderPath with default flags (0) verifies that the target folder physically exists, raising FileNotFoundError in sandboxed Windows environments where USERPROFILE points to a directory without AppData\Local. This was a regression introduced in 4.7.0 when PR #380 replaced SHGetFolderPathW with SHGetKnownFolderPath. Passing KF_FLAG_DONT_VERIFY (0x00004000) restores the pre-4.7.0 behavior of returning the expected path without existence checks, matching how the old SHGetFolderPathW API worked. Closes #421 Signed-off-by: Bernát Gábor <bgabor8@bloomberg.net> * test(windows): use real ctypes on Windows CI On Windows, call get_win_folder_via_ctypes with the real Windows API for each CSIDL name to verify integration. Reserve mock-based tests for non-Windows where ctypes Windows bindings don't exist. * fix(tests): resolve unused type-ignore warnings on Windows Move ctypes.WinDLL mock assignment into _setup_ctypes_mocks so the type: ignore comment only exists in one place that ty can reason about. --------- Signed-off-by: Bernát Gábor <bgabor8@bloomberg.net>
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The ctypes backend on Windows used
SHGetFolderPathW, a legacy API that Microsoft has marked deprecated since Windows Vista. It relies on integer CSIDL constants and has a hard-codedMAX_PATH(260 char) buffer, which silently truncates long paths. TheCSIDL_DOWNLOADSfolder had no dedicated constant at all, requiring a brittle workaround that appended"Downloads"to the user profile path -- breaking for any user who relocated their Downloads folder.🔄 This replaces it with
SHGetKnownFolderPath, the modern successor that uses KnownFolder GUIDs and allocates its own buffer (noMAX_PATHlimit). Every folder -- including Downloads and Desktop -- now has a proper GUID, so theCSIDL_DOWNLOADSworkaround is gone. The DLL function signatures are declared with properargtypes/restypeinstead of relying on the untypedctypes.windllsingleton, and the allocated memory is freed viaCoTaskMemFreeas required by the API contract.The fallback chain (ctypes -> registry -> env vars) is preserved. The
_pick_get_win_folderselector is simplified sincectypes.WinDLLis always available whenctypesis importable on CPython.Fix #348
Co-authored-by: moi15moi moi15moismokerlolilol@gmail.com