Fix DateTime.Now and CurrentTimeToUtc during DST transition time (#4172)

[mono.git] / mcs / class / corlib / System / TimeZoneInfo.cs

diff --git a/mcs/class/corlib/System/TimeZoneInfo.cs b/mcs/class/corlib/System/TimeZoneInfo.cs
index bbb5051574b32924789a8df1ca4d12a63e6812fe..7a12080c6a89b822ca68d4806c861d4785655836 100644 (file)
--- a/mcs/class/corlib/System/TimeZoneInfo.cs
+++ b/mcs/class/corlib/System/TimeZoneInfo.cs
@@ -826,7 +826,7 @@ namespace System
                                        return tz.BaseUtcOffset;
                        }
 
-                       if (tzRule != null && tz.IsInDST (tzRule, stdUtcDateTime)) {
+                       if (tzRule != null && tz.IsInDST (tzRule, dateTime)) {
                                // Replicate what .NET does when given a time which falls into the hour which is lost when
                                // DST starts. isDST should always be true but the offset should be BaseUtcOffset without the
                                // DST delta while in that hour.
@@ -883,7 +883,7 @@ namespace System
                        AdjustmentRule rule = GetApplicableRule (dateTime);
                        if (rule != null) {
                                DateTime tpoint = TransitionPoint (rule.DaylightTransitionEnd, dateTime.Year);
-                               if (dateTime > tpoint - rule.DaylightDelta  && dateTime <= tpoint)
+                               if (dateTime > tpoint - rule.DaylightDelta && dateTime <= tpoint)
                                        return true;
                        }
                                
@@ -913,7 +913,6 @@ namespace System
                                DST_start -= BaseUtcOffset;
                                DST_end -= (BaseUtcOffset + rule.DaylightDelta);
                        }
-
                        return (dateTime >= DST_start && dateTime < DST_end);
                }
                
@@ -1199,31 +1198,16 @@ namespace System
                                        return false;
                        }
 
-                       var inDelta = false;
-                       for (var i =  transitions.Count - 1; i >= 0; i--) {
-                               var pair = transitions [i];
-                               DateTime ttime = pair.Key;
-                               TimeType ttype = pair.Value;
-
-                               var delta =  new TimeSpan (0, 0, ttype.Offset) - BaseUtcOffset;
-
-                               if ((ttime + delta) > date) {
-                                       inDelta = ttime <= date;
-                                       continue;
-                               }
-
-                               offset =  new TimeSpan (0, 0, ttype.Offset);
-                               if (inDelta) {
-                                       // Replicate what .NET does when given a time which falls into the hour which is lost when
-                                       // DST starts. isDST should be true but the offset should be the non-DST offset.
-                                       isDst = transitions [i - 1].Value.IsDst;
-                               } else {
-                                       isDst = ttype.IsDst;
+                       AdjustmentRule current = GetApplicableRule(date);
+                       if (current != null) {
+                               DateTime tStart = TransitionPoint(current.DaylightTransitionStart, date.Year);
+                               DateTime tEnd = TransitionPoint(current.DaylightTransitionEnd, date.Year);
+                               if ((date >= tStart) && (date <= tEnd)) {
+                                       offset = baseUtcOffset + current.DaylightDelta; 
+                                       isDst = true;
+                                       return true;
                                }
-
-                               return true;
                        }
-
                        return false;
                }
 
@@ -1513,7 +1497,7 @@ namespace System
 
                        if (zone.IsAmbiguousTime (time)) {
                                isAmbiguousLocalDst = true;
-                               return baseOffset;
+//                             return baseOffset;
                        }
 
                        return zone.GetUtcOffset (time, out isDaylightSavings);