I was going through the code here and found out that it's completely …

…missing

the point, it could be much tighter and easier to understand. So here's the
candidate replacement code plus some assertions, I intend to let it run for
some time and if no assertion errors come up (they shouldn't) do the replace.

This was almost my very first Moodle code. Isn't experience wonderful? ;-)

calendar/lib.php

@@ -116,6 +116,20 @@ function calendar_get_mini($courses, $groups, $users, $cal_month = false, $cal_y
         $startwday += 7;
     }
 
+    // TODO: THIS IS TEMPORARY CODE!
+    // [pj] I was just reading through this and realized that I when writing this code I was probably
+    // asking for trouble, as all these time manipulations seem to be unnecessary and a simple
+    // make_timestamp would accomplish the same thing. So here goes a test:
+    $test_start = make_timestamp($y, $m, 1);
+    $test_end   = make_timestamp($y, $m, $display->maxdays, 23, 59, 59);
+    if($test_start != usertime($display->tstart) - dst_offset_on($display->tstart)) {
+        notify('Failed assertion in calendar/lib.php line 126; display->tstart = '.$display->tstart.', dst_offset = '.dst_offset_on($display->tstart).', usertime = '.usertime($display->tstart).', make_t = '.$test_start);
+    }
+    if($test_end != usertime($display->tend) - dst_offset_on($display->tend)) {
+        notify('Failed assertion in calendar/lib.php line 130; display->tend = '.$display->tend.', dst_offset = '.dst_offset_on($display->tend).', usertime = '.usertime($display->tend).', make_t = '.$test_end);
+    }
+
+
     // Get the events matching our criteria. Don't forget to offset the timestamps for the user's TZ!
     $whereclause = calendar_sql_where(
         usertime($display->tstart) - dst_offset_on($display->tstart),