Subject: Re: bug#30743: 26.0.91; ERT "wrong-type-argument" errors

From: Glenn Morris <[email-masked]>
Date: Fri, 16 Mar 2018 15:21:34 -0400

Are you sure that you are actually running Emacs 26.0.91 and its
associated lisp files? From the original report:

  value of $EMACSLOADPATH: /tmp/nff/de2/fedora-emacs-src/emacs-26.0/lisp

Perhaps those files are old.

M-x locate-library ert, and examine the result.