posh-git
A PowerShell environment for Git
...The prompt within Git repositories can show the current branch and the state of files (additions, modifications, deletions) within. Provides tab completion for common commands when using git. Prompt formatting, among other things, can be customized. Displaying file status in the git prompt for a very large repo can be prohibitively slow. Rather than turn off file status entirely, you can disable it on a repo-by-repo basis by adding individual repository paths. PowerShell generates its prompt by executing a prompt function, if one exists. posh-git defines such a function in profile.example.ps1 that outputs the current working directory followed by an abbreviated git status.