From 92de44fa1fdeda74a9b8254f968829df4c957da0 Mon Sep 17 00:00:00 2001 From: Noam Postavsky Date: Sat, 17 Mar 2018 21:14:11 -0400 Subject: [PATCH] Don't error when indenting malformed Lisp (Bug#30891) * lisp/emacs-lisp/lisp-mode.el (lisp-indent-calc-next): If we run out of indent stack, reset the parse state. --- lisp/emacs-lisp/lisp-mode.el | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/lisp/emacs-lisp/lisp-mode.el b/lisp/emacs-lisp/lisp-mode.el index 205c810b978..13ad06e4aee 100644 --- a/lisp/emacs-lisp/lisp-mode.el +++ b/lisp/emacs-lisp/lisp-mode.el @@ -827,6 +827,10 @@ by more than one line to cross a string literal." (prog1 (let (indent) (cond ((= (forward-line 1) 1) nil) + ;; Negative depth, probably some kind of syntax error. + ((null indent-stack) + ;; Reset state. + (setq ppss (parse-partial-sexp (point) (point)))) ((car indent-stack)) ((integerp (setq indent (calculate-lisp-indent ppss))) (setf (car indent-stack) indent))