GitRebaseBranches

RebaseBranches.ps1

param(
    [Parameter(Mandatory)]
    [String[]]$Branches
)

$newLineChar = [Environment]::NewLine
Write-Output $newLineChar

[String[]]$commitCountMsgs = @()
[String[]]$scriptOutputLines = @()

for ($i=0;$i -lt ($Branches.Count - 1); $i++){
    $baseBranch = $Branches[$i]
    $rebaseBranch = $Branches[$i + 1]

    $mergeBaseCmd = "git merge-base $baseBranch $rebaseBranch"
    $mergeBase = Invoke-Expression -Command $mergeBaseCmd

    $branchLastRefCmd = "git rev-parse $rebaseBranch"
    $branchLastRef = Invoke-Expression -Command $branchLastRefCmd

    $commitCountCmd = "git rev-list ${mergeBase}..${branchLastRef} --count"
    $commitCount = Invoke-Expression -Command $commitCountCmd

    $commitCountMsgs += "$commitCount commits between $baseBranch & $rebaseBranch."
    $scriptOutputLines += "git checkout $rebaseBranch"
    $scriptOutputLines += "git rebase --onto $baseBranch ${rebaseBranch}~${commitCount} $rebaseBranch"
}

Write-Output $commitCountMsgs
Write-Output $newLineChar
Write-Output $scriptOutputLines