Fix a small incompatibility in ibuffer

Translate nil values from column functions to the empty string, so that
subsequent calls to string-width don't signal an error (Bug#26317).
* lisp/ibuffer.el (ibuffer-compile-format): If a column function returns
nil, treat it like the empty string.

1 files changed, 1 insertions, 1 deletions

diff --git a/lisp/ibuffer.el b/lisp/ibuffer.el
index 66916b2bca1..c83c21315a1 100644
--- a/lisp/ibuffer.el
+++ b/lisp/ibuffer.el
@@ -1689,7 +1689,7 @@ If point is on a group name, this function operates on that group."
                     ;; generate a call to the column function.
                     (ibuffer-aif (assq sym ibuffer-inline-columns)
                         (nth 1 it)
-                      `(,sym buffer mark)))
+                      `(or (,sym buffer mark) "")))
                    ;; You're not expected to understand this.  Hell, I
                    ;; don't even understand it, and I wrote it five
                    ;; minutes ago.