Git for Windows "No tags file" Response from "git diff" Command

Question

Git version: 2.14.2.2

Whenever I run git diff on a repository I am greeted with the response No tags file. I have tried running the command on multiple repositories, multiple consoles (Cmd, PowerShell, MINGW64, Visual Studio Command Prompt) and all have the same response.

Strangely, the git log command also fails. Many other commands work, however, such as git status, git pull, etc. It seems to be only log and diff.

I have uninstalled Git entirely and reinstalled. Restarted my system. Tried referencing the git.exe directly (which yields the exact same response). Nothing is working and I have not seen this error anywhere else. I compared my user configs with those of a colleague and they are identical.

Some portion of the command executes properly, because if I supply two commit hashes, and I intentionally break one, the response I receive is:

It seems like another program may be hijacking the git diff command. I believe this because I'm not sure "No tags file" is even a possible Git response. Not sure what else it would be.

To make things even more confusing- my ultimate goal is to run the git diff within the context of an msbuild and it DOES EXECUTE CORRECTLY. Now, I could be satisfied with this, but I need to modify the diff command slightly, and running a full build each time is not productive, nor easy to troubleshoot. There is a task within the build script that runs an Exec command and it has no issues performing the diff. I'm also able to execute a Diff Against Current within SourceTree, which to the best of my knowledge, runs a git diff behind the scenes.

Any help would be very much appreciated.

:: Edits ::

Various commands:

git diff HEAD~1 HEAD
git diff master~1 master
git diff <commit-hash-1> <commit-hash-2>
git log HEAD~1..HEAD
git log master~1..master
git log <commit-hash-1>..<commit-hash-2>

Output:

Every one of the commands above returns the same No tags file response, in all of my repos.

Cat Head:

cd .git
cat HEAD
ls -R refs

Output:

New Repo:

mkdir testrepo
cd testrepo
git init
echo "file1" > file1.txt
git add .
git commit -m "initial commit of file1.txt"
echo "Hi there!" > file2.txt
git add .
git commit -m "added file2.txt"
git log
git diff HEAD~1 HEAD

Output:

git config -e:

git config --global -e:

::Edits 2::

I uninstalled all of my diffing/source control tools (SourceTree, Git, SVN, WinMerge, KDiff). Installed the portable version of Git. Opened CMD to a repo, put in full path to the git.exe portable and it still returned the No tags file response.

I also reviewed all of my path variables for: git, vim, ming, mintty and anything else that seemed suspect, but didn't find any.

I have restarted after performing all steps, and yet the problem persists.

::Edits 3::

I have a different user on my laptop, switched to that user and the git diff works properly, so clearly there is something with my main user that is conflicting. Will continue to look into my User directory for issues.

Answer 1

Here are the steps I'd take in this situation:

1. Try the following and check the response:

   git diff HEAD~1 HEAD
   git diff master~1 master
   git diff <commit-hash-1> <commit-hash-2>
   

2. Try the same with log:

   git log HEAD~1..HEAD
   git log master~1..master
   git log <commit-hash-1>..<commit-hash-2>
   

   I'm actually guessing that your refs are messed up, which means that the direct hashes might work, but the HEAD and/or master one may not.

3. Look into the .git/refs folder

   From the main repo folder:

   cd .git
   cat HEAD
   ls -R refs
   

   Hopefully, HEAD is pointing to a branch, and if master is checked out, cat HEAD output should look like:

   ref: refs/heads/master
   

   Then, the ls -R refs, should show a heads folder, with files for each of your local branches (i.e. master and possibly others). You also likely have refs/remotes and refs/tags directories.

   If any of these things are radically different or missing, that could be your issue...

4. Since you have reinstalled git, create a brand new repo and try the same commands:

   mkdir testrepo
   cd testrepo
   git init
   echo "file1" > file1.txt
   git add .
   git commit -m "initial commit of file1.txt"
   echo "Hi there!" > file2.txt
   git add .
   git commit -m "added file2.txt"
   git log
   git diff HEAD~1 HEAD
   

   If this last one works, then git is likely working okay, but some tool you have is messing things up.

5. Post your config from git config -e and git config --global -e - maybe we can see something?