1  (require 'ert)
 2  
 3  (defun measure-emacs-startup ()
 4    (float-time (time-subtract after-init-time before-init-time)))
 5  
 6  (ert-deftest test-emacs-startup-time ()
 7    "Display Emacs' startup time."
 8    :tags '(performance startup-time)
 9    (let ((load-time (measure-emacs-startup)))
10      (should (numberp load-time))
11      (message "⏰ Emacs startup time: %.3f second(s)" load-time)
12      (should t)))
13  
14  (provide 'startup-time)