don't show git status inside `.git` dir

functions/fish_prompt.fish

@@ -1,7 +1,9 @@
 # git helper functions
 # unused
 function __git_is_repo -d "Test if the current directory is a Git repository"
-    if not command git rev-parse --git-dir > /dev/null 2>/dev/null
+    # don't consider the .git dir as part of the repo
+    # so we use --show-toplevel (which fails inside .git) instead of --git-dir
+    if not command git rev-parse --show-toplevel > /dev/null 2>/dev/null
         return 1
     end
 end
@@ -140,6 +142,7 @@ function fish_prompt
         segment $base_color " $pwd_info[3] "
     end
 
+    if __git_is_repo
         if set branch_name (__git_branch_name)
 
             if __git_is_stashed
@@ -193,6 +196,7 @@ function fish_prompt
             end
             segment "$git_color[1]" "$git_color[2]" "$prompt"
         end
+    end
 
     segment $base_color " $dir"(set_color $text_color)"$base "