Here's my normal method for supporting their GIT based repository on a non-Microsoft system.. Can I do a similar thing with Source Tree. I do a lot of code sharing.. Note my client doesn't used stash. I am using Source Tree with Xamarin and Visual Studio online..
First of all, create a hosted TFS account and added a New Team Project + Git
Create alternative login credentials since you cannot have an @ symbol in your login info. Follow the Create Team Project and Enable alternative Credentials instructionshere
After enabling the alternative credentials open Xamarin Studio and my solution file open as well.
Under the Version Control menu item select Publish (Only available with solution file open)
Select the Registered Repositiories tab and select Add
Enter an appropriate name. Select https protocol.
Enter your hosted TFS URL ie. xxx.visualstudio.com.
For port, enter 443.
The path will be: /DefaultCollection/_git/ + project name (exactly as you typed it including spaces)
User will be the alternative username you created in step 2. Click OK on both open windows.
You will be prompted to confirm publishing. Select OK.
You will then be prompted for your password. Enter you alternative password you created in step 2. If you accidentally enter the wrong password here, you must delete the entry from your key chain. Instructions can be found here
The way to test this:
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