feat: add gf shortcut that does an interactive git fixup

users/myuser/git.nix

@@ -66,6 +66,25 @@
     gca = "git commit -v -S --amend";
     gcl = "git clone";
     gcr = "git commit-reuse-message -v -S";
+    gf = lib.getExe (pkgs.writeShellApplication {
+      name = "git-fixup-fzf";
+      runtimeInputs = [pkgs.fzf pkgs.gnugrep];
+      text = ''
+        if ! commit=$(git log --graph --color=always --format="%C(auto)%h%d %s %C(reset)%C(bold)%cr" "$@" \
+          | fzf --ansi --multi --no-sort --reverse --print-query --expect=ctrl-d --toggle-sort=\`); then
+          echo aborted
+          exit 0
+        fi
+
+        sha=$(grep -o '^[^a-z0-9]*[a-z0-9]\{7\}[a-z0-9]*' <<< "$commit" | grep -o '[a-z0-9]\{7\}[a-z0-9]*')
+        if [[ -z "$sha" ]]; then
+          echo "Found no checksum for selected commit. Aborting."
+          exit 1
+        fi
+
+        git fixup "$sha" "$@"
+      '';
+    });
     gp = "git push";
     gpf = "git push --force";
     gs = "git s";