Improvements on (TICKS . HZ)

This patch is in response to Eli's review (Bug#32902#10).
* src/systime.c: Doc strings of affected functions now refer
to format-time-string instead of to Lisp manual, and
format-time-string's doc string covers time values.
* test/src/systime-tests.el (format-time-string-with-zone):
Check decode-time too.
(decode-then-encode-time, time-arith-tests): New tests.

1 files changed, 89 insertions, 27 deletions

diff --git a/test/src/timefns-tests.el b/test/src/timefns-tests.el
index 435dcf7db70..ebeb43de163 100644
--- a/test/src/timefns-tests.el
+++ b/test/src/timefns-tests.el
@@ -19,7 +19,7 @@
 
 (require 'ert)
 
-;;; Check format-time-string with various TZ settings.
+;;; Check format-time-string and decode-time with various TZ settings.
 ;;; Use only POSIX-compatible TZ values, since the tests should work
 ;;; even if tzdb is not in use.
 (ert-deftest format-time-string-with-zone ()
@@ -35,32 +35,61 @@
   ;; Similarly, stick to the limited set of time zones that are
   ;; supported by both POSIX and MS-Windows: exactly 3 ASCII letters
   ;; in the abbreviation, and no DST.
-  (let ((look '(1202 22527 999999 999999))
-        (format "%Y-%m-%d %H:%M:%S.%3N %z (%Z)"))
-    ;; UTC.
-    (should (string-equal
-             (format-time-string "%Y-%m-%d %H:%M:%S.%3N %z" look t)
-             "1972-06-30 23:59:59.999 +0000"))
-    ;; "UTC0".
-    (should (string-equal
-             (format-time-string format look "UTC0")
-             "1972-06-30 23:59:59.999 +0000 (UTC)"))
-    ;; Negative UTC offset, as a Lisp list.
-    (should (string-equal
-             (format-time-string format look '(-28800 "PST"))
-             "1972-06-30 15:59:59.999 -0800 (PST)"))
-    ;; Negative UTC offset, as a Lisp integer.
-    (should (string-equal
-             (format-time-string format look -28800)
-             ;; MS-Windows build replaces unrecognizable TZ values,
-             ;; such as "-08", with "ZZZ".
-             (if (eq system-type 'windows-nt)
-                 "1972-06-30 15:59:59.999 -0800 (ZZZ)"
-               "1972-06-30 15:59:59.999 -0800 (-08)")))
-    ;; Positive UTC offset that is not an hour multiple, as a string.
-    (should (string-equal
-             (format-time-string format look "IST-5:30")
-             "1972-07-01 05:29:59.999 +0530 (IST)"))))
+  (let ((format "%Y-%m-%d %H:%M:%S.%3N %z (%Z)"))
+    (dolist (look '((1202 22527 999999 999999)
+		    (7879679999900 . 100000)
+		    (78796799999999999999 . 1000000000000)))
+      ;; UTC.
+      (should (string-equal
+	       (format-time-string "%Y-%m-%d %H:%M:%S.%3N %z" look t)
+	       "1972-06-30 23:59:59.999 +0000"))
+      (should (equal (decode-time look t)
+		     '(59 59 23 30 6 1972 5 nil 0)))
+      ;; "UTC0".
+      (should (string-equal
+	       (format-time-string format look "UTC0")
+	       "1972-06-30 23:59:59.999 +0000 (UTC)"))
+      (should (equal (decode-time look "UTC0")
+		     '(59 59 23 30 6 1972 5 nil 0)))
+      ;; Negative UTC offset, as a Lisp list.
+      (should (string-equal
+	       (format-time-string format look '(-28800 "PST"))
+	       "1972-06-30 15:59:59.999 -0800 (PST)"))
+      (should (equal (decode-time look '(-28800 "PST"))
+		     '(59 59 15 30 6 1972 5 nil -28800)))
+      ;; Negative UTC offset, as a Lisp integer.
+      (should (string-equal
+	       (format-time-string format look -28800)
+	       ;; MS-Windows build replaces unrecognizable TZ values,
+	       ;; such as "-08", with "ZZZ".
+	       (if (eq system-type 'windows-nt)
+		   "1972-06-30 15:59:59.999 -0800 (ZZZ)"
+		 "1972-06-30 15:59:59.999 -0800 (-08)")))
+      (should (equal (decode-time look -28800)
+		     '(59 59 15 30 6 1972 5 nil -28800)))
+      ;; Positive UTC offset that is not an hour multiple, as a string.
+      (should (string-equal
+	       (format-time-string format look "IST-5:30")
+	       "1972-07-01 05:29:59.999 +0530 (IST)"))
+      (should (equal (decode-time look "IST-5:30")
+		     '(59 29 5 1 7 1972 6 nil 19800))))))
+
+(ert-deftest decode-then-encode-time ()
+  (let ((time-values (list 0 -2 1 0.0 -0.0 -2.0 1.0
+			   most-negative-fixnum most-positive-fixnum
+			   (1- most-negative-fixnum)
+			   (1+ most-positive-fixnum)
+			   1e+INF -1e+INF 1e+NaN -1e+NaN
+			   '(0 1 0 0) '(1 0 0 0) '(-1 0 0 0)
+			   '(123456789000000 . 1000000)
+			   (cons (1+ most-positive-fixnum) 1000000000000)
+			   (cons 1000000000000 (1+ most-positive-fixnum)))))
+    (dolist (a time-values)
+      (let* ((d (ignore-errors (decode-time a t)))
+	     (e (encode-time d))
+	     (diff (float-time (time-subtract a e))))
+	(should (or (not d)
+		    (and (<= 0 diff) (< diff 1))))))))
 
 ;;; This should not dump core.
 (ert-deftest format-time-string-with-outlandish-zone ()
@@ -80,3 +109,36 @@
 
 (ert-deftest time-equal-p-nil-nil ()
   (should (time-equal-p nil nil)))
+
+(ert-deftest time-arith-tests ()
+  (let ((time-values (list 0 -1 1 0.0 -0.0 -1.0 1.0
+			   most-negative-fixnum most-positive-fixnum
+			   (1- most-negative-fixnum)
+			   (1+ most-positive-fixnum)
+			   1e+INF -1e+INF 1e+NaN -1e+NaN
+			   '(0 0 0 1) '(0 0 1 0) '(0 1 0 0) '(1 0 0 0)
+			   '(-1 0 0 0) '(1 2 3 4) '(-1 2 3 4)
+			   '(-123456789 . 100000) '(123456789 . 1000000)
+			   (cons (1+ most-positive-fixnum) 1000000000000)
+			   (cons 1000000000000 (1+ most-positive-fixnum)))))
+    (dolist (a time-values)
+      (dolist (b time-values)
+	(let ((aa (time-subtract (time-add a b) b)))
+	  (should (or (time-equal-p a aa) (and (floatp aa) (isnan aa)))))
+	(should (= 1 (+ (if (time-less-p a b) 1 0)
+			(if (time-equal-p a b) 1 0)
+			(if (time-less-p b a) 1 0)
+			(if (or (and (floatp a) (isnan a))
+				(and (floatp b) (isnan b)))
+			    1 0))))
+	(should (or (not (time-less-p 0 b))
+		    (time-less-p a (time-add a b))
+		    (time-equal-p a (time-add a b))
+		    (and (floatp (time-add a b)) (isnan (time-add a b)))))
+	(let ((x (float-time (time-add a b)))
+	      (y (+ (float-time a) (float-time b))))
+	  (should (or (and (isnan x) (isnan y))
+		      (= x y)
+		      (< 0.99 (/ x y) 1.01)
+		      (< 0.99 (/ (- (float-time a)) (float-time b))
+			 1.01))))))))