git difftool runs git diff

Question

I am obviously overlooking something very simple here, but I am not seeing it. The command

webstorm diff ~/test.txt ~/test2.txt

runs the J

Answer 1

I just had the same problem. My git diftool configuration has been set up in my ~/.gitconfig and has been working fine, but today weirdly git difftool worked in one repo but ran git diff in another.

Fix: I updated from git 2.11.0 to git 2.11.1 and the problem seems to have gone away.

The git 2.11.1 release notes mention fixing a difftool-related regression. The described problem isn't what I was seeing, but maybe the fix fixed it anyway.

Answer 2

Run:

GIT_TRACE=1 git difftool --tool-help

to print a list of diff tools that may be used with --tool, and which are not available.

---

Secondly I believe the following simplified example may work better:

[difftool "webstorm"]
  cmd = webstorm diff "$LOCAL" "$REMOTE"

Or by specifying the path to the binary or script, e.g.

[difftool]
  prompt = NO
  external = /usr/local/bin/diffmerge

---

Check the diff configuration by:

git config --get-regex diff

Or more specifically (replace webstorm with your tool name):

git config --get difftool.webstorm.cmd

---

If still doesn't work, test it on the new repository, e.g. by following these commands:

mkdir ~/git_test && cd ~/git_test
git init && touch file && git add file && git commit -m'Adds file' -a
echo changed >> file
GIT_TRACE=1 git difftool

If above works, then make sure your repository config doesn't have anything unexpected, e.g.

more "$(git rev-parse --show-toplevel)"/.git/config

---

If you're in merge state (check by git status), you need to use mergetool instead, e.g.

git mergetool

^{Add -t tool to specify which tool. List available by git mergetool --tool-help.}

---

See also man git-difftool:

CONFIG VARIABLES
       git difftool falls back to git mergetool config variables when the difftool equivalents have not been
       defined.

       diff.tool
           The default diff tool to use.

       diff.guitool
           The default diff tool to use when --gui is specified.

       difftool.<tool>.path
           Override the path for the given tool. This is useful in case your tool is not in the PATH.

       difftool.<tool>.cmd
           Specify the command to invoke the specified diff tool.

           See the --tool=<tool> option above for more details.

       difftool.prompt
           Prompt before each invocation of the diff tool.