diff --git a/t/t5801/git-remote-testgit b/t/t5801/git-remote-testgit
index c5b10f5775..f8b476499f 100755
--- a/t/t5801/git-remote-testgit
+++ b/t/t5801/git-remote-testgit
@@ -26,7 +26,8 @@ then
 	t_refspec=""
 fi
 
-GIT_DIR="$url/.git"
+unset $(git rev-parse --local-env-vars)
+GIT_DIR=$(git -C "$url" rev-parse --absolute-git-dir)
 export GIT_DIR
 
 force=