Summary of the new feature/enhancement

Especially in the Unix world, symlinks are often define with relative target paths, which enables you to later move the symlink along with its target to a different directory subtree without breaking the link.

The .Target ETS property we add to FileInfo / DirectoryInfo instances reports a symlink's target path as defined (though there is an open bug regarding the current behavior on Unix: #13365).

However, it would also be convenient to have an easy way to resolve the target path to a full (absolute) path, which is cumbersome to do manually:

# Given $symlink as a FileInfo / DirectoryInfo instance:
$fullTargetPath = [IO.Path]::GetFullPath($symlink.Target, (Split-Path $symLink.FullName))

Proposed technical implementation details (optional)

Add a new .ResolvedTarget ETS property to FileInfo / DirectoryInfo instances that behaves as follows:

• Resolve the target path to a full path as shown above:

  • If the resulting path exists, report it as such.
  • Otherwise, report $null to indicate that the symlink is broken.

• If the item at hand isn't a symlink / reparse point, simply report its own full path - this allows unified treatment of symlinks and non-symlinks, as a simple way to get an item's full path.

Ideally, the .ResolvedTarget property would return a FileInfo / DirectoryInfo rather than a path string (with $null as the return value if the target doesn't exist), but there are two considerations:

• performance in general
• to be consistent with Get-Item / Get-ChildItem output, the usual PS provider properties must be added to the output FileInfo / DirectoryInfo instances, such as .PSPath.

To mitigate performance issues, .ResolvedTarget should only be calculated on demand and therefore be implemented as a CodeMethod property (which .Target is too).

Related issues:

• Proposed API for symbolic links dotnet/runtime#24271 (comment) (.NET Core API suggestion to add a System.IO.Path.GetFullPath() overload for canonical path resolution).

• Support getting canonical filesystem paths with symlinks resolved, similar to the Linux realpath utility #10640 (PowerShell-side proposal to implement canonical path resolution via Convert-Path -Canonical).