git-lfs-unlock-unchanged.ps1

[CmdletBinding()] # Fail on unknown args
param (
    [switch]$dryrun = $false,
    [switch]$help = $false
)

function Print-Usage {
    Write-Output "Git LFS unlock-unchanged"
    Write-Output "   Unlock all files which are unchanged locally."
    Write-Output "   To be unlocked a file must not be modified in the working"
    Write-Output "   copy, nor be part of any commits which haven't been pushed."
    Write-Output "Usage:"
    Write-Output "  git-lfs-unlock-unchanged.ps1 [options]"
    Write-Output "Options:"
    Write-Output " "
    Write-Output "  -dryrun      : Don't perform actions, just report what would happen"
    Write-Output "  -verbose     : Print more"
    Write-Output "  -help        : Print this help"

}

$ErrorActionPreference = "Stop"

if ($help) {
    Print-Usage
    Exit 0
}

. $PSScriptRoot\inc\locking.ps1
. $PSScriptRoot\inc\status.ps1

Write-Output "Checking for locked but unchanged files..."

$modifiedFiles = Get-Modified-Files 
Write-Verbose ("Modified files:`n    " + ($modifiedFiles -join "`n    "))

$lfsPushOutput = git lfs push --dry-run origin HEAD
if (!$?) {
    Write-Output "ERROR: failed to call 'git lfs push --dry-run'"
    Exit 5
}

# Result format is of the form
# push f4ee401c063058a78842bb3ed98088e983c32aa447f346db54fa76f844a7e85e => Path/To/File
# With some potential informationals we can ignore

$filesToBePushed = [System.Collections.ArrayList]@()
foreach ($line in $lfsPushOutput) {
    if ($line -match "^push ([a-f0-9]+)\s+=>\s+(.+)$") {
        $oid = $matches[1]
        $filename = $matches[2]
        $filesToBePushed.Add($filename.Trim()) > $null
    }
}

# Wrap in @() to avoid collapsing to a single string when only 1 file
$filesToBePushed = @($filesToBePushed | Select-Object -Unique)
Write-Verbose ("Files awaiting push: `n    " + ($filesToBePushed -join "`n    "))

$lockedFiles = Get-Locked-Files
Write-Verbose ("Locked files: `n    " + ($lockedFiles -join "`n    "))

$filesToUnlock = [System.Collections.ArrayList]@()
foreach ($filename in $lockedFiles) {
    if (-not ($modifiedFiles -contains $filename) -and -not ($filesToBePushed -contains $filename)) {
        $filesToUnlock.Add($filename) > $null
        Write-Verbose "  $filename isn't modified or awaiting push, will unlock"
    }
}

if ($filesToUnlock.Count -gt 0) {
    if ($dryrun) {
        Write-Output ("Would have unlocked:`n    " + ($filesToUnlock -join "`n    "))
    } else {
        foreach ($filename in $filesToUnlock) {
            git lfs unlock $filename
        }
    }
}