le-python.el (lispy--python-poetry-name): Don't fail outside of project

File can be outside of project (so no root) or may not use poetry/pyproject.toml.

Author: EugeneNeuron

le-python.el

@@ -298,8 +298,8 @@ it at one time."
 (defvar lispy--python-init-file nil)
 
 (defun lispy--python-poetry-name ()
-  (let ((pyproject
-         (file-name-directory (locate-dominating-file (buffer-file-name) "pyproject.toml"))))
+  (when-let* ((root (locate-dominating-file (buffer-file-name) "pyproject.toml"))
+              (pyproject (file-name-directory root)))
     (and (file-exists-p pyproject)
          (not (equal python-shell-interpreter "python"))
          (with-current-buffer (find-file-noselect pyproject)