Feature request: abbreviate path from git root

[elsassph]

System Details

• posh-git version/path: 1.0.0 beta3 ~/.local/share/powershell/Modules/posh-git/1.0.0
• PowerShell version: 6.2.3
• git version 2.21.0 (Apple Git-122.2)
• OS: Unix 18.7.0.0

Issue Description

My abbreviated path can be pretty long and maybe there could be an option to abbreviate based on the closest git root (including the folder name), so it would essentially show the path within the project I'm working.

e.g.

~/company/work/projects/client/project-name/src [master] >

Could be further shortened to:

-/project-name/src [master] >

[elsassph]

What are the contributions guidelines? Has this feature (with proposed implementation) a chance to be accepted?
cc @dahlbyk @rkeithhill

[rkeithhill]

We should probably have some contribution guidelines. Short version, following the existing coding style in the function/script you're modifying. If there are tests for the function you are modifying, please add new Pester tests to cover the changed/new functionality. All tests must pass before PR would be accepted. And yes, IMO I would accept this feature. My only question is would it be enough to add an optional parameter to the Get-PromptPath function which would require the user to have to change the $GitPromptSettings.DefaultPromptPath setting. Or should we also add yet another setting to enable this feature? Could go either way.

[elsassph]

@rkeithhill well I also did a PR adding an extra option for it. CI is green, but I'll look into adding a test specific to it.

Maybe the path manipulations would be worth extracting into more easily testable functions BTW, unless that would add noise (I'm not familiar with all subtleties of pwsh).

[dahlbyk]

Closed by #720. Thanks for the contribution!