zsh: cd to git repository root with ctrl-g in the line editor

config/zsh/line-editor.zsh

@@ -52,6 +52,17 @@ bindkey -M viins '^[f' vi-forward-word
 # Shortcut to start neovim.
 bindkey -s '^v' '^unvim\r'
 
+# cd to the root of the git repository (if within one).
+cd-git-root() {
+  local top_level="$(git rev-parse --show-toplevel 2>/dev/null)"
+  [[ -z "$top_level" ]] && return 1
+  zle push-line
+  BUFFER="builtin cd -- ${(q)top_level}"
+  zle accept-line
+}
+zle -N cd-git-root
+bindkey -M viins '^g' cd-git-root
+
 if command -v fzf >/dev/null 2>&1; then
   # Add `fzf` key bindings if it's installed:
   #   - CTRL-T: paste the selected file path(s) into the command line