More-compatible subsecond calendrical timestamps

Instead of appending a subseconds member to the result of
‘decode-time’, this keeps the format unchanged unless you give
a new optional argument to ‘decode-time’.  Also, the augmented
format now puts the subsecond info in the SECONDS element, so
the total number of elements is unchanged; this is more
compatible with code that expects the traditional 9 elements,
such as ‘(pcase decoded-time (`(,SEC ,MIN ,HOUR ,DAY ,MON
,YEAR ,DOW ,DST ,ZONE) ...) ...)’.
* doc/lispref/os.texi, doc/misc/emacs-mime.texi, etc/NEWS:
* lisp/net/soap-client.el (soap-decode-date-time):
* lisp/simple.el (decoded-time):
Document the new behavior.
* lisp/calendar/icalendar.el (icalendar--decode-isodatetime):
* lisp/calendar/iso8601.el (iso8601-parse)
(iso8601-parse-time, iso8601-parse-duration)
(iso8601--decoded-time):
* lisp/calendar/parse-time.el (parse-time-string):
* lisp/calendar/time-date.el (decoded-time-add)
(decoded-time--alter-second):
* lisp/org/org.el (org-parse-time-string):
* lisp/simple.el (decoded-time):
* src/timefns.c (Fdecode_time, Fencode_time):
* test/lisp/calendar/icalendar-tests.el:
(icalendar--decode-isodatetime):
* test/lisp/calendar/iso8601-tests.el (test-iso8601-date-years)
(test-iso8601-date-dates, test-iso8601-date-obsolete)
(test-iso8601-date-weeks, test-iso8601-date-ordinals)
(test-iso8601-time, test-iso8601-combined)
(test-iso8601-duration, test-iso8601-intervals)
(standard-test-dates, standard-test-time-of-day-fractions)
(standard-test-time-of-day-beginning-of-day)
(standard-test-time-of-day-utc)
(standard-test-time-of-day-zone)
(standard-test-date-and-time-of-day, standard-test-interval):
* test/lisp/calendar/parse-time-tests.el (parse-time-tests):
* test/src/timefns-tests.el (format-time-string-with-zone)
(encode-time-dst-numeric-zone):
Revert recent changes that added a SUBSECS member to
calendrical timestamps, since that component is no longer
present (the info, if any, is now in the SECONDS member).
* lisp/calendar/time-date.el (decoded-time-add)
(decoded-time--alter-second):
Support fractional seconds in the new form.  Simplify.
* src/timefns.c (Fdecode_time): Support new arg FORM.
(Fencode_time): Support subsecond resolution.
* test/src/timefns-tests.el (format-time-string-with-zone)
(decode-then-encode-time): Test subsecond calendrical timestamps.

1 files changed, 4 insertions, 10 deletions

diff --git a/lisp/calendar/iso8601.el b/lisp/calendar/iso8601.el
index 51f5dff9091..30352c7e75f 100644
--- a/lisp/calendar/iso8601.el
+++ b/lisp/calendar/iso8601.el
@@ -129,8 +129,7 @@ well as variants like \"2008W32\" (week number) and
         (let ((time (iso8601-parse-time time-string)))
           (setf (decoded-time-hour date) (decoded-time-hour time))
           (setf (decoded-time-minute date) (decoded-time-minute time))
-	  (setf (decoded-time-second date) (decoded-time-second time))
-	  (setf (decoded-time-subsec date) (decoded-time-subsec time))))
+          (setf (decoded-time-second date) (decoded-time-second time))))
       ;; The time zone is optional.
       (when zone-string
         (setf (decoded-time-zone date)
@@ -237,8 +236,6 @@ well as variants like \"2008W32\" (week number) and
           (iso8601--decoded-time :hour hour
                                  :minute (or minute 0)
                                  :second (or second 0)
-				 ;; FIXME: Support subsec.
-				 :subsec 0
                                  :zone (and zone
                                             (* 60 (iso8601-parse-zone
                                                    zone)))))))))
@@ -277,9 +274,7 @@ Return the number of minutes."
                            :day (or (match-string 3 string) 0)
                            :hour (or (match-string 5 string) 0)
                            :minute (or (match-string 6 string) 0)
-			   :second (or (match-string 7 string) 0)
-			   ;; FIXME: Support subsec.
-			   :subsec 0))
+                           :second (or (match-string 7 string) 0)))
    ;; PnW: Weeks.
    ((iso8601--match iso8601--duration-week-match string)
     (let ((weeks (string-to-number (match-string 1 string))))
@@ -341,7 +336,7 @@ Return the number of minutes."
 
 (cl-defun iso8601--decoded-time (&key second minute hour
                                       day month year
-                                      dst zone subsec)
+                                      dst zone)
   (list (iso8601--value second)
         (iso8601--value minute)
         (iso8601--value hour)
@@ -350,8 +345,7 @@ Return the number of minutes."
         (iso8601--value year)
         nil
         dst
-        zone
-	subsec))
+        zone))
 
 (defun iso8601--encode-time (time)
   "Like `encode-time', but fill in nil values in TIME."