* TODO Test coverage [6/38]
  - [ ] chronometrist-idle-timer ()
  - [ ] chronometrist-current-project ()
  - [ ] chronometrist-project-active? (project)
  - [X] chronometrist-seconds-to-hms (seconds)
  - [ ] chronometrist-entries ()
  - [ ] chronometrist-project-at-point ()
  - [ ] chronometrist-goto-last-project ()
  - [X] chronometrist-time-add (a b)
  - [X] chronometrist-total-time-one-day (&optional date)
  - [ ] chronometrist-print-non-tabular ()
  - [ ] chronometrist-toggle-project (&optional arg)
  - [ ] chronometrist (&optional arg)
  - [ ] chronometrist-day-of-week->number (day-of-week)
  - [ ] chronometrist-date-op (date operator &optional count)
  - [X] chronometrist-report-previous-week-start (date)
  - [ ] chronometrist-report-date ()
  - [ ] chronometrist-report-date->dates-in-week (first-date-in-week)
  - [ ] chronometrist-report-dates-in-week->string (dates-in-week)
  - [ ] chronometrist-report-date->week-dates ()
  - [ ] chronometrist-report-entries ()
  - [ ] chronometrist-report-idle-timer ()
  - [ ] chronometrist-report-format-date (format-string time-date)
  - [ ] chronometrist-report-print-non-tabular ()
  - [ ] chronometrist-report (&optional keep-week)
  - [ ] chronometrist-report-previous-week (arg)
  - [ ] chronometrist-report-next-week (arg)
  - [ ] chronometrist-buffer-exists? (buffer-name)
  - [ ] chronometrist-buffer-visible? (buffer-or-buffer-name)
  - [ ] chronometrist-timestamp->list (date-time-string)
  - [ ] chronometrist-timestamp-list->seconds (date-time-list)
  - [ ] chronometrist-timestamp->seconds (date-time-string)
  - [ ] chronometrist-time-interval-span-midnight? (t1 t2)
  - [ ] chronometrist-first-event-spans-midnight? (target-date project)
  - [ ] chronometrist-get-end-time (target-date)
  - [X] chronometrist-project-time-one-day (project &optional date)
  - [ ] chronometrist-format-time (time)
  - [ ] chronometrist-open-file ()
  - [X] interval-test (start target)