Fix TZ problem with datetime<.

2 files changed, 16 insertions, 6 deletions

diff --git a/module/datetime.scm b/module/datetime.scm
index 8df055de..2b330a9c 100644
--- a/module/datetime.scm
+++ b/module/datetime.scm
@@ -262,14 +262,18 @@
       (time< a b)))
 
 (define-public (datetime< a b)
-  (if (date= (get-date a) (get-date b))
-      (time< (get-time a) (get-time b))
-      (date< (get-date a) (get-date b))))
+  (let ((a (get-datetime a))
+        (b (get-datetime b)))
+    (if (date= (get-date a) (get-date b))
+        (time< (get-time% a) (get-time% b))
+        (date< (get-date a) (get-date b)))))
 
 (define-public (datetime<= a b)
-  (if (date= (get-date a) (get-date b))
-      (time<= (get-time a) (get-time b))
-      (date<= (get-date a) (get-date b))))
+  (let ((a (get-datetime a))
+        (b (get-datetime b)))
+   (if (date= (get-date a) (get-date b))
+       (time<= (get-time% a) (get-time% b))
+       (date<= (get-date a) (get-date b)))))
 
 (define-public (date/-time< a b)
   (datetime< (as-datetime a) (as-datetime b)))
diff --git a/tests/datetime-compare.scm b/tests/datetime-compare.scm
index eab2b949..cd077e87 100644
--- a/tests/datetime-compare.scm
+++ b/tests/datetime-compare.scm
@@ -64,6 +64,12 @@
 (test-assert "date/-time< other dt, same date"
   (date/-time< #2020-01-01 #2020-01-01T10:00:00))
 
+;; In UTC+2 (CEST) the below datetime overflows into midnight the following
+;; day. Earlier versions of this program only looked at the time component
+(test-assert "date/-time< TZ overflow"
+  (date/-time< #2020-04-05
+               (datetime date: #2020-04-05 time: #22:00:00 tz: "UTC")))
+
 (test-assert "date/-time< time-only"
   (date/-time< #00:00:00 #10:00:00))