PR Summary

Add an explicit check that the destination path is not a subdirectory of the source path.

PR Context

When DirectoryInfo.MoveTo() is used and the destination is a subfolder of the source, an Access Denied exception is returned. However, the error code for this cannot be differentiated from other Access Denied cases like you don't have permission for the destination or across DFS volumes. So the FileSystemProvider falls back to CopyAndDelete() to handle this case. However, for this scenario, this results in infinite recursion.

Since you can't move a parent into a child path, it makes sense to check for this condition and return an error. This is a regression from 7.1 due to other changes needed for FileSystemProvider to fix other Move-item behavior.

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