Improve FileUtils.forceDelete() tests on Windows#791
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garydgregory merged 7 commits intomasterfrom Oct 2, 2025
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On Windows, the `DeleteFile` Win32 API has a little quirk: it refuses to delete files with the legacy **DOS read-only attribute** set. (Because apparently 99% of Windows users don’t realize that “deleting a file” is actually an operation on the *directory*, not the file itself 😉). So the usual drill is: clear the read-only flag first, then delete. * Until JDK 25, `File.delete()` did this for you behind the scenes: it quietly stripped the flag before calling into `DeleteFile`. That meant your file might be left behind (with the flag missing) if the *real* ACLs didn’t allow deletion. * From JDK 25 onward, `File.delete()` doesn’t touch the flag anymore. If the bit is set, `DeleteFile` fails, end of story. * `FileUtils.forceDelete()` already knows how to juggle the flag itself, so its behavior didn’t change. This PR: * Updates two tests that were (unfairly) comparing `File.delete` with `FileUtils.forceDelete`. With JDK 25, their expectations diverged. * Adds a new test to confirm that `FileUtils.forceDelete` restores the read-only flag if the actual deletion fails. > [!WARNING] > I didn’t develop this on a Windows box, so I couldn’t test it locally. Leaving this as a **draft PR** until CI tells us whether Windows agrees with me.
ppkarwasz
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Introduce a helper that snapshots file and parent directory attributes before `setReadOnly` is applied. If a deletion attempt fails, the holder can restore the original attributes to keep the filesystem state consistent.
On Linux/Unix, both POSIX and DOS attribute views may be supported, while on Windows only DOS attributes are available. Check for POSIX first to ensure the correct view is used across platforms.
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Merged, thank you @ppkarwasz. |
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Since the issues around I’ve opened three follow-up JIRA tickets to track the remaining problems:
Partial fixes for these are available in the |
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On Windows, the
DeleteFileWin32 API has a little quirk: it refuses to delete files with the legacy DOS read-only attribute set. (Because apparently 99% of Windows users don’t realize that “deleting a file” is actually an operation on the directory, not the file itself 😉).So the usual drill is: clear the read-only flag first, then delete.
File.delete()did this for you behind the scenes: it quietly stripped the flag before calling intoDeleteFile. That meant your file might be left behind (with the flag missing) if the real ACLs didn’t allow deletion.File.delete()doesn’t touch the flag anymore. If the bit is set,DeleteFilefails, end of story.FileUtils.forceDelete()already knows how to juggle the flag itself, so its behavior didn’t change.This PR:
File.deletewithFileUtils.forceDelete. With JDK 25, their expectations diverged.Adds a new test to confirm thatFileUtils.forceDeleterestores the read-only flag if the actual deletion fails.