Compare two directory inventories
Documentation: Microsoft Learn
Both sides get enumerated with Get-ChildItem into a projection of FullName, Length, and LastWriteTime, and Compare-Object is told to compare on exactly those three properties.
The script
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$PathA = "C:\Deploy\Current"
$PathB = "C:\Deploy\Previous"
Compare-Object (Get-ChildItem $PathA -File -Recurse | Select-Object FullName,Length,LastWriteTime) (Get-ChildItem $PathB -File -Recurse | Select-Object FullName,Length,LastWriteTime) -Property FullName,Length,LastWriteTime- Stage 1$PathA
Positional values or no named parameters
How it works
Both sides get enumerated with Get-ChildItem into a projection of FullName, Length, and LastWriteTime, and Compare-Object is told to compare on exactly those three properties. Rows tagged with a left-pointing SideIndicator exist only under $PathA, and right-pointing rows are unique to $PathB.
Adapting it
The comparison only means something once the paths are relative, so build a calculated property that trims $PathA and $PathB off the front of FullName and compare on that instead.
If the result is unexpected
Every file is reported as a difference, each appearing on exactly one side, even though the two trees were confirmed identical by other means.
The comparison includes FullName, which embeds the root path, so no file from one tree can ever match a file from the other. Compare-Object is doing precisely what it was told to do. LastWriteTime is also compared at full tick precision, so a copy that preserved timestamps only to the second still registers as different.
- Replace FullName with a calculated relative path that strips the root before the comparison runs.
- Drop LastWriteTime from the property list, or round it, if the copy method does not preserve sub-second precision.
- Compare on Length alone first to confirm the file sets match before adding timestamps back in.
- Run Get-FileHash on the remaining differences when content equality is what actually matters.
- Check for a trailing separator difference between the two root variables, which shifts every relative path by one character.
Validate the result
Comparing the corrected projections across two known-identical trees produces no output at all, which is what Compare-Object emits when the sets match.
Keep the check reliable
Normalize to relative paths before any cross-tree comparison, and hash content when the answer has to be authoritative rather than indicative.
