powershell.md

Tweak things in PowerShell

- CONTENTS -

• Keep each command item unique in PSReadLine history file

Keep each command item unique in PSReadLine history file

Tested with PowerShell v7.3.6 and PSReadLine v2.3.1-beta1. It should also work with later versions but not with older ones (can even cause loss of command history).

Steps:

1. Run the following command to update PSReadLine in PowerShell. (VERY IMPORTANT!)

   Update-Module PSReadLine -AllowPrerelease

2. Add the following code to your PowerShell profile:

   Set-PSReadLineOption -AddToHistoryHandler {
     # A hack to keep each item unique in the history file.
     param([string]$itemNew)
     $historyFile = (Get-PSReadLineOption).HistorySavePath
     if (!(Test-Path $historyFile)) {
       return $true
     }
     $items = [ordered]@{}
     $sb = [System.Text.StringBuilder]::new()
     Get-Content $historyFile | ForEach-Object {
       if ($_.Length -eq 0) {
         return
       }
       [void]$sb.Append($_)
       if ($_.EndsWith('`')) {
         [void]$sb.Append("`n")
         return
       }
       $item = $sb.ToString()
       if ($items.Contains($item)) {
         $items.Remove($item)
       }
       $items.Add($item, $null)
       [void]$sb.Clear()
     }
     if ($items.Contains($itemNew)) {
       $items.Remove($itemNew)
     }
     $items.Keys | Out-File $historyFile -Force
     return $true
   }

3. Restart PowerShell.