Xcode couldn't communicate with helper application

[QwazyWabbit]

I installed SourceTree for Mac for use with Bitbucket projects but now Xcode can't commit to my local Git repositories created prior to installing SourceTree. I maintain several local GIT and remote SVN repositories on my MacBook Pro and Xcode has always offered to create them when creating new projects but now, after installing SourceTree, I cannot commit to or create any repositories from within Xcode.

Deleting the SourceTree app doesn't repair this.

It seems SourceTree is interfering with Xcode's ability to commit to and maintain these repos. Querying and comparing working copy with repository appears to work normally.

Upon commit, Xcode says "Couldn't communicate with a helper application".

How do I get SourceTree to let Xcode do its thing directly on these repositories?

SourceTree for Mac v2.3

[QwazyWabbit · Accepted solution]

Further research and I can answer my own question:

Solution: Don't leave Full name and Email address blank in Preferences General.

[Zbyszek Pietras]

It still works! THX

[BigMike]

The location in Xcode preferences has changed in Xcode 10.2.1, now under Source Control -> Git.  I entered my Developer ID full name and email address and it work perfectly first time.

[Dan Esrey]

I wasn't able to add my name and email in Preferences; if I typed in the values and then navigated to a different window and back again, my changes were gone. What I ended up doing was using terminal. 

xcrun git config -- global user.name "your name"
xcrun git config -- global user.email email address

[AalokJIPL]

The solution is to add changes once with a git command. Use terminal and navigate to Xcode project folder. If you are in the right folder, this command:

ls -al

will list a .git folder. Then you know you're in the right place. Then execute

git commit -a -m "Commit title here"

After that commit via Xcode should work again. If not try the same steps again for 2 to 3 times.

I just check the git status and try to commit again 3 times and the issue is resolved.