Gaurav » powershell

Multiple ways to open PowerShell in the current Explorer window

Gaurav — Tue, 14 Oct 2008 16:42:35 +0000

These techniques are generic and can be used for other items like command prompt as well. A word of caution, everything given below involves fiddling with the registry so please backup your system’s registry or create a restore point before trying this out.

1) Adding it to Vista Explorer’s toolbar:

This is the most convenient one in my opinion, but requires most work to enable it.

Firstly, navigate to the following registry key:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\explorer\FolderTypes\{7d49d726-3c21-4f05-99aa-fdc2c9474656}

Its should have the following items:

Note that it has following two items:

TasksItemsSelected: Enabled when an item is selected in the view.
TasksNoItemsSelected: Enabled when nothing is selected in the view.

Each of these keys have multiple items inside them each pointing to separate shortcut inside the toolbar.

Import the following registry file so that the PowerShell icon appears in the toolbar:

Download From Skydrive

Before importing I will also point out that I am assuming the a batch file exists at the following path:

C:\\Users\\Gaurav\\Programs\\shortcuts\\psh_launch.bat %2

The content of this file should be:

@echo off
pushd %1
%SystemRoot%\system32\WindowsPowerShell\v1.0\powershell.exe
@echo

You can search and replace the location of this file to your custom location inside the just downloaded registry file. Its being used in two places.

Also, remember to take a backup of this registry key or make a restore point before importing this registry key.

That’s it. Now a PowerShell Icon should appear inside the every folder.

The PowerShell icon still doesn’t appear?

Actually the registry file only modifies the folders of Document Type and the PowerShell icon will appear only inside folders of Document Type.

An easy way to make all the folders inside a Drive Document Type:

right click on drive/partition –> select Properties –> select Customize tab-> and select following options:

So this way we just forced all the folders in the drive to be of Document Type.

The same procedure can be used to add multiple items on the toolbar. Its a lot of work but the end result is worth it :)

2) Using AutoHotKey

AutoHotKey is used for creating keyboard macros.

AutoHotKey will use the same batch file that was created to launch PowerShell in the current directory.

Here is the script:

!p::
IfWinActive ahk_class CabinetWClass
{
WinGetClass explorerClass, A
ControlGetText currentPath, Edit1, ahk_class %explorerClass%
run C:\\Users\\Gaurav\\Programs\\shortcuts\\psh_launch.bat "%currentPath%"
}
return

Just fix path to the batch file, save and reload AutoHotKey.

Now press Alt + P to launch PowerShell inside the current explorer window.

3) Right Click Menu

To add PowerShell to right click menu navigate to following registry entry:

HKEY_CLASSES_ROOT\Directory\Background\shell

and create a key with name powershell inside shell and a key with name command inside it. Edit the default value of command key to:

C:\Users\Gaurav\Programs\shortcuts\psh_launch.bat “%V”

This is same batch file created earlier and the exact path needs to be fixed.

or just import this file into your registry and fix the path to the batch file:

Download from Skydrive

That’s it, now PowerShell should show up in you right-click menu inside any directory.

Context sensitive auto-completion using PowerShell, PowerTab and GIT

Gaurav — Mon, 13 Oct 2008 19:33:46 +0000

Powertab is an Awesome PowerShell TabExpansion extension. It extends the default PowerShell autocompletion and shows the results like:

The best part is that it is easily customizable.

One way to customize it is by editing it Tab Expansion database file which is located in your powershell profile directory:

TabExpansion.xml

To display some simple git commands in autocompletion all the following entries to it:

<Custom>
  <Filter>gitFilter>
  <Text>statusText>
  <Type>CustomType>
Custom>
<Custom>
  <Filter>gitFilter>
  <Text>add .Text>
  <Type>CustomType>
Custom>
<Custom>
  <Filter>gitFilter>
  <Text>pullText>
  <Type>CustomType>
Custom>
<Custom>
  <Filter>gitFilter>
  <Text>pushText>
  <Type>CustomType>
Custom>
<Custom>
  <Filter>gitFilter>
  <Text>commit -m ""Text>
  <Type>CustomType>
Custom>
<Custom>
  <Filter>gitFilter>
  <Text>commit -a -m ""Text>
  <Type>CustomType>
Custom>

To invoke this list add the following to TabExpansion.ps1 file which should be in the source directory:

'git(.*)' {
  if(Test-Path .git) {
    $global:dsTabExpansion.Tables['Custom'].select("filter = 'git' AND type = 'Custom'") | % {$_.text} | Invoke-TabItemSelector  -SelectionHandler $SelectionHandler
  }
}

This should be added in the Main tabcompletion block inside the switch statement. The function is basically matching the current command name with git and then invoking autocompletion.

Now when you type git then the output should look like below:

I am sure this is not the best way to do custom autocompletion but i couldn’t find an easier way.

This is all static stuff. To add dynamic autocompletion (like providing branch names) add following to the TabExpansion.ps1 file:

'git(.*)' {
  if(Test-Path .git) {
    # git checkout
    if($lastBlock -match 'git checkout'){
      git branch | %{ if($_ -match "^\*?\s*(.*)"){ $matches[1] } } | Invoke-TabItemSelector  -SelectionHandler $SelectionHandler
    }
    else{
      $global:dsTabExpansion.Tables['Custom'].select("filter = 'git' AND type = 'Custom'") | % {$_.text} | Invoke-TabItemSelector  -SelectionHandler $SelectionHandler
    }
  }
}

Now when you type git checkout then it should show the following in the autocomplete list:

This function checks if the user has entered git checkout as the command then it runs the git branch command, parses it and shows the result as autocomplete list.

Here are couple more commands that I wrote while trying this out:

'git(.*)' {
  if(Test-Path .git) {
    # git checkout
    if($lastBlock -match 'git checkout'){
      git branch | %{ if($_ -match "^\*?\s*(.*)"){ $matches[1] } } | Invoke-TabItemSelector  -SelectionHandler $SelectionHandler
    }
    
    # git add
    Elseif($lastBlock -match 'git add'){
      $s = $False ; git status | %{ if($s -eq $True -and $_ -match "^#\s{1,1}(\S.+)$"){ $matches[1] } ElseIf($_ -match 'Untracked files:'){ $s = $True } } | Invoke-TabItemSelector  -SelectionHandler $SelectionHandler
    }
    
    # git rm
    Elseif($lastBlock -match 'git rm'){
      git status | %{ if($_ -match "^#\s+deleted:\s+(\S.+)$"){ $matches[1] } } | Invoke-TabItemSelector  -SelectionHandler $SelectionHandler
    }
    
    else{
      $global:dsTabExpansion.Tables['Custom'].select("filter = 'git' AND type = 'Custom'") | % {$_.text} | Invoke-TabItemSelector  -SelectionHandler $SelectionHandler
    }
  }
}

These will autocomplete parameters for git add and git rm commands by running the git status command and parsing the output.

For example:

I think a lot more interesting stuff can be created using PowerTab and GIT.

Update 1:

Turns out as pointed by MOW that there is a much easier way to add custom expansions instead of editing the TabExpansion.xml file.

Just run this command inside PowerShell:

Invoke-TabExpansionEditor

It will open up a dialog box like:

Here custom items can be added by clicking the Custom link and then the database change can by saved by running the command:

Export-tabExpansionDataBase

Displaying GIT Branch on your PowerShell prompt

Gaurav — Sun, 12 Oct 2008 07:48:28 +0000

PowerShell is a command line shell like the command prompt (cmd.exe) but with a lot more features. It can be downloaded from here.

One of the features is that you can change the default prompt. Prompt can be changed by overriding the function with name “prompt”.

This function can be declared inside the PowerShell profile file which has the path:

C:\Users\Gaurav\Documents\WindowsPowerShell\Microsoft.PowerShell_profile.ps1

If the file does not exist then you will need to create this file. Declaring the following function inside the profile file will change the prompt.

function prompt {
  return "prompt> "
}

to:

Now, to display the git branch as a prompt change the function to the following:

function prompt {
  $host.ui.rawui.WindowTitle = $(get-location)
  
  $prompt_string = ""
  
  if(Test-Path .git) {
    $prompt_string = "GIT"
    git branch | foreach {
      if ($_ -match "^\*(.*)"){
        $prompt_string += $matches[1] + "> "
      }
    }
  }
  else{
    $prompt_string = "PS> "
  }
  
  Write-Host ($prompt_string) -nonewline -foregroundcolor yellow
  return " "
}

and the prompt will look like:

The code basically is checking if current directory is a git project. This can be done by checking if there is a directory with name “.git” in the current directory. If yes then it runs the “git branch” command and then passes the result through a regular expression to get the current branch.

Here is my full PowerShell prompt function:

$Global:CurrentUser = [System.Security.Principal.WindowsIdentity]::GetCurrent()
$UserType = "User"
$CurrentUser.Groups | foreach { if($_.value -eq "S-1-5-32-544") {$UserType = "Admin"} }
  
function prompt {
  if($UserType -eq "Admin") {
    $host.ui.rawui.WindowTitle = "" + $(get-location) + " : Admin"
    $host.UI.RawUI.ForegroundColor = "Yellow"
  }
  else {
    $host.ui.rawui.WindowTitle = $(get-location)
  }
  
  Write-Host("")
  
  $status_string = ""
  
  if(Test-Path .git) {
    $status_string = "GIT"
    git branch | foreach {
      if ($_ -match "^\*(.*)"){
        $status_string += $matches[1]
      }
    }
    
    $git_create_count = 0
    $git_update_count = 0
    $git_delete_count = 0
    
    git status | foreach {
      if($_ -match "modified:"){ 
        $git_update_count += 1
      }
      elseif($_ -match "deleted:"){ 
        $git_delete_count += 1
      }
      elseif($_ -match "added:"){ 
        $git_create_count += 1
      }
    }
    $status_string += " u:" + $git_update_count + " d:" + $git_delete_count + ">"
  }
  else{
    $status_string = "PS>"
  }
  
  Write-Host ($status_string) -nonewline -foregroundcolor yellow
  return " "
}

This function also displays updated and deleted files in the current git project.

Scripts execution in PowerShell is disabled?

If you just created the profile file then PowerShell may display the following error message when loading this profile we just created:

File C:\Users\Gaurav\Documents\WindowsPowerShell\Microsoft.PowerShell_profile.ps1 cannot be loaded because the execution of scripts is disabled on this system. Please see “get-help about_signing” for more details.
At line:1 char:2
+ . <<<< ‘C:\Users\Gaurav\Documents\WindowsPowerShell\Microsoft.PowerShell_profile.ps1′

This is because PowerShell does not allow the execution of scripts by default. To fix this open PowerShell in Admin mode and set the execution policy to unrestricted by running the following command:

   1: Set-ExecutionPolicy Unrestricted