Clear TestDrive with .NET IO instead of per-item Remove-Item#2917
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nohwnd wants to merge 1 commit into
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Clear TestDrive with .NET IO instead of per-item Remove-Item#2917nohwnd wants to merge 1 commit into
nohwnd wants to merge 1 commit into
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Clear-TestDrive ran Remove-Item -Path -Force -Recurse for every new root item after each block. Remove-Item costs ~470us per item where IO.Directory/IO.File Delete costs ~85us, and -Path treats the path as a wildcard pattern, so a file named like 'file[1].txt' was never deleted and leaked across block teardowns. The .NET calls treat the path literally, delete reparse points without following them into their target (same as Remove-TestDrive already does for the whole drive since 2021), and anything that throws (read-only files on Windows, locked files) falls back to Remove-Item -LiteralPath -Force -ErrorAction Ignore, keeping the old semantics for those. Also replaced a Join-Path with plain string interpolation in New-RandomTempRegistry, registry provider paths always use backslash. 🤖
This was referenced Jul 19, 2026
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Jul 19, 2026
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| # registry provider paths always use backslash; plain interpolation avoids a per-call cmdlet invocation | ||
| $Path = "$tempPath\$([IO.Path]::GetRandomFileName().Substring(0, 4))" |
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Not really a hot path, but sure 👍
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got some free fable tokens, told it to optimize (especially the hot path), looks like most of the optimizations are microscopic.
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Clear-TestDriveranRemove-Item -Path $item -Force -Recurse -ErrorAction Ignorefor every new root item after each block. Two problems with that:Remove-Itemcosts ~470us per item where[IO.Directory]::Delete/[IO.File]::Deletecost ~85us. On a TestDrive-heavy suite the cleanup was the single hottest line in the profile.-Pathtreats the path as a wildcard pattern. A file named likefile[1].txtnever matched its own name, was never deleted, and leaked across block teardowns. The reverse is also possible, a name with*in it could over-delete. The .NET calls treat the path literally, so this is also a small bug fix.Symlink semantics stay the same: recursive
Directory.Deleteremoves reparse points without following them into their target, which is whatRemove-TestDrivehas already been doing for the whole drive with the exact same call since 2021. I verified this empirically on macOS with dir symlinks, file symlinks, dangling links, the PowerShell/PowerShell#621 problematic link set, and a symlink cycle, the linked target content survives in all cases. Anything that throws (read-only files on Windows, locked files) falls back toRemove-Item -LiteralPath -Force -Recurse -ErrorAction Ignore, keeping the old behavior for those, just slower on that rare path.A ride-along in
New-RandomTempRegistry:Join-Pathreplaced with plain string interpolation, registry provider paths always use backslash and the base key has no trailing separator, so the result is identical and it skips a cmdlet invocation per new registry key.One heads-up: the symlink tests in
TestDrive.Tests.ps1are entirely commented out (they needed admin on Windows), so nothing in CI exercises symlink cleanup today. Might be worth re-enabling them at least on Linux/macOS runners in a separate PR.Verification: full suite green on macOS (inline and dot-sourced build),
TestDrive.Tests.ps1including the Clear-TestDrive #2657 regression suite andPester.TestDrive.ts.ps1pass.Related perf PRs: #2914, #2915, #2916, #2918. Measured together they cut ~21% from four representative workloads (inline build, macOS).
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