public/Get-Up.ps1
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<#
.SYNOPSIS Gets the path of an ancestor directory, either by name or by traversing upwards by the given number of levels. .PARAMETER n Number of levels above the starting location. (One by default.) .PARAMETER NamePart Partial directory name for which to search. .PARAMETER From The directory from which to start. $PWD by default. .EXAMPLE # Get the parent of the current location C:\Windows\System32> Get-Up C:\Windows C:\Windows\System32> _ .EXAMPLE # Get the grandparent of the current location C:\Windows\System32\drivers\etc> Get-Up 2 C:\Windows\System32 C:\Windows\System32\drivers\etc> _ .EXAMPLE # Get the first ancestor containing the term 'win' C:\Windows\System32\drivers\etc> Get-Up win C:\Windows C:\Windows\System32\drivers\etc> _ .LINK Undo-Location #> function Get-Up { [OutputType([String])] [CmdletBinding(DefaultParameterSetName = 'n')] param( [Parameter(ParameterSetName = 'n', Position = 0)] [byte]$n = 1, [Parameter(ParameterSetName = 'named', Position = 0)] [string]$NamePart, [Parameter(ValueFromPipeline = $true)] [string] $From = $PWD ) $ancestors = Get-Ancestors -From $From if ($PSCmdlet.ParameterSetName -eq 'n') { if (!$n) { return $From } return $ancestors.Path | select -Index ($n - 1) } if ($PSCmdlet.ParameterSetName -eq 'named') { if ($result = $ancestors | where Name -like "$NamePart*") { return $result.Path | select -first 1 } # if we couldn't match by leaf name then match by complete path # this is mainly used for completion when MenuCompletion is off if ($result = $ancestors.Path -eq $NamePart) { return $result | select -first 1 } Write-Error "Could not find '$NamePart' as an ancestor of '$From'." -ErrorAction Stop } } |