I understand it is a hidden file in the project folder:
XCode has to adhere to the same Git repository rules as anything else, which means that the root project folder has a (hidden) folder called '.git' where all the repository data is kept. So the root project folder is your git repository folder, and SourceTree can use that too.
the git repository is the directory ".git" inside your project directory.
Setting the "Source Path/URL" of a SourceTree bookmark to the top level Xcode project works for me with Xcode 4.2.
To show hidden files
Hope that helps.
Perfect. Thanks very much.
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