mcs/class/corlib/Test/System/TimeZoneTest.cs

   1 //
   2 // TimeZoneTest.cs - NUnit Test Cases for the System.TimeZone struct
   3 //
   4 // Authors:
   5 //      Martin Baulig (martin@gnome.org)
   6 //      Sebastien Pouliot  <sebastien@ximian.com>
   7 //
   8 //   (C) 2002 Martin Baulig
   9 // Copyright (C) 2005 Novell, Inc (http://www.novell.com)
  10 //
  11
  12 using NUnit.Framework;
  13 using System;
  14 using System.IO;
  15 using System.Threading;
  16 using System.Globalization;
  17 using System.Runtime.Serialization.Formatters.Binary;
  18
  19 namespace MonoTests.System {
  20
  21 [TestFixture]
  22 public class TimeZoneTest {
  23
  24         private void CET (TimeZone t1)
  25         {
  26                 Assert.AreEqual("CET", t1.StandardName, "A01");
  27                 Assert.AreEqual("CEST", t1.DaylightName, "A02");
  28
  29                 DaylightTime d1 = t1.GetDaylightChanges (2002);
  30                 Assert.AreEqual("03/31/2002 02:00:00", d1.Start.ToString ("G", CultureInfo.InvariantCulture), "A03");
  31                 Assert.AreEqual("10/27/2002 03:00:00", d1.End.ToString ("G", CultureInfo.InvariantCulture), "A04");
  32                 Assert.AreEqual(36000000000L, d1.Delta.Ticks, "A05");
  33
  34                 DaylightTime d2 = t1.GetDaylightChanges (1996);
  35                 Assert.AreEqual("03/31/1996 02:00:00", d2.Start.ToString ("G", CultureInfo.InvariantCulture), "A06");
  36                 Assert.AreEqual("10/27/1996 03:00:00", d2.End.ToString ("G", CultureInfo.InvariantCulture), "A07");
  37                 Assert.AreEqual(36000000000L, d2.Delta.Ticks, "A08");
  38
  39                 DateTime d3 = new DateTime (2002,2,25);
  40                 Assert.AreEqual(false, t1.IsDaylightSavingTime (d3), "A09");
  41                 DateTime d4 = new DateTime (2002,4,2);
  42                 Assert.AreEqual(true, t1.IsDaylightSavingTime (d4), "A10");
  43                 DateTime d5 = new DateTime (2002,11,4);
  44                 Assert.AreEqual(false, t1.IsDaylightSavingTime (d5), "A11");
  45
  46                 Assert.AreEqual(36000000000L, t1.GetUtcOffset (d3).Ticks, "A12");
  47                 Assert.AreEqual(72000000000L, t1.GetUtcOffset (d4).Ticks, "A13");
  48                 Assert.AreEqual(36000000000L, t1.GetUtcOffset (d5).Ticks, "A14");
  49
  50                 // Test TimeZone methods with UTC DateTime in DST.
  51                 DateTime d6 = d4.ToUniversalTime ();
  52                 Assert.AreEqual(false, t1.IsDaylightSavingTime (d6), "A15");
  53                 Assert.AreEqual(0, t1.GetUtcOffset (d6).Ticks, "A16");
  54         }
  55
  56         private void EST (TimeZone t1)
  57         {
  58                 // It could be EST though...
  59                 //Assert.AreEqual("Eastern Standard Time", t1.StandardName, "B01");
  60                 //Assert.AreEqual("Eastern Daylight Time", t1.DaylightName, "B02");
  61
  62                 DaylightTime d1 = t1.GetDaylightChanges (2002);
  63                 Assert.AreEqual("04/07/2002 02:00:00", d1.Start.ToString ("G", CultureInfo.InvariantCulture), "B03");
  64                 Assert.AreEqual("10/27/2002 02:00:00", d1.End.ToString ("G", CultureInfo.InvariantCulture), "B04");
  65                 Assert.AreEqual(36000000000L, d1.Delta.Ticks, "B05");
  66
  67                 DaylightTime d2 = t1.GetDaylightChanges (1996);
  68                 Assert.AreEqual("04/07/1996 02:00:00", d2.Start.ToString ("G", CultureInfo.InvariantCulture), "B06");
  69                 Assert.AreEqual("10/27/1996 02:00:00", d2.End.ToString ("G", CultureInfo.InvariantCulture), "B07");
  70                 Assert.AreEqual(36000000000L, d2.Delta.Ticks, "B08");
  71
  72                 DateTime d3 = new DateTime (2002,2,25);
  73                 Assert.AreEqual(false, t1.IsDaylightSavingTime (d3), "B09");
  74                 DateTime d4 = new DateTime (2002,4,8);
  75                 Assert.AreEqual(true, t1.IsDaylightSavingTime (d4), "B10");
  76
  77                 DateTime d5 = new DateTime (2002,11,4);
  78                 Assert.AreEqual(false, t1.IsDaylightSavingTime (d5), "B11");
  79
  80                 Assert.AreEqual(-180000000000L, t1.GetUtcOffset (d3).Ticks, "B12");
  81                 Assert.AreEqual(-144000000000L, t1.GetUtcOffset (d4).Ticks, "B13");
  82                 Assert.AreEqual(-180000000000L, t1.GetUtcOffset (d5).Ticks, "B14");
  83
  84                 // Test TimeZone methods with UTC DateTime in DST.
  85                 DateTime d6 = d4.ToUniversalTime ();
  86                 Assert.AreEqual(false, t1.IsDaylightSavingTime (d6), "B15");
  87                 Assert.AreEqual(0, t1.GetUtcOffset (d6).Ticks, "B16");
  88         }
  89
  90         private void TST (TimeZone t1)
  91         {
  92                 Assert.AreEqual("Tokyo Standard Time", t1.StandardName, "C01");
  93                 Assert.AreEqual("Tokyo Standard Time", t1.DaylightName, "C02");
  94
  95                 DateTime d3 = new DateTime (2002,2,25);
  96                 Assert.AreEqual(false, t1.IsDaylightSavingTime (d3), "C09");
  97                 DateTime d4 = new DateTime (2002,4,8);
  98                 Assert.AreEqual(false, t1.IsDaylightSavingTime (d4), "C10");
  99                 DateTime d5 = new DateTime (2002,11,4);
 100                 Assert.AreEqual(false, t1.IsDaylightSavingTime (d5), "C11");
 101
 102                 Assert.AreEqual(324000000000L, t1.GetUtcOffset (d3).Ticks, "C12");
 103                 Assert.AreEqual(324000000000L, t1.GetUtcOffset (d4).Ticks, "C13");
 104                 Assert.AreEqual(324000000000L, t1.GetUtcOffset (d5).Ticks, "C14");
 105         }
 106
 107         private void GMT (TimeZone t1) {
 108                 // Probably wont work on MS.NET, but is better than nothing. Where do
 109                 // we change our implementation to match theirs?
 110
 111                 Assert.AreEqual("GMT", t1.StandardName, "D01");
 112                 Assert.IsTrue("BST" == t1.DaylightName || "IST" == t1.DaylightName, "D02");
 113
 114                 DaylightTime d1 = t1.GetDaylightChanges (2002);
 115                 Assert.AreEqual("03/31/2002 01:00:00", d1.Start.ToString ("G", CultureInfo.InvariantCulture), "D03");
 116                 Assert.AreEqual("10/27/2002 02:00:00", d1.End.ToString ("G", CultureInfo.InvariantCulture), "D04");
 117                 Assert.AreEqual(36000000000L, d1.Delta.Ticks, "D05");
 118
 119                 DaylightTime d2 = t1.GetDaylightChanges (1996);
 120                 Assert.AreEqual("03/31/1996 01:00:00", d2.Start.ToString ("G", CultureInfo.InvariantCulture), "D06");
 121                 Assert.AreEqual("10/27/1996 02:00:00", d2.End.ToString ("G", CultureInfo.InvariantCulture), "D07");
 122                 Assert.AreEqual(36000000000L, d2.Delta.Ticks, "D08");
 123
 124                 DateTime d3 = new DateTime (2002,2,25);
 125                 Assert.AreEqual(false, t1.IsDaylightSavingTime (d3), "D09");
 126                 DateTime d4 = new DateTime (2002,4,2);
 127                 Assert.AreEqual(true, t1.IsDaylightSavingTime (d4), "D10");
 128                 DateTime d5 = new DateTime (2002,11,4);
 129                 Assert.AreEqual(false, t1.IsDaylightSavingTime (d5), "D11");
 130
 131                 Assert.AreEqual(0L, t1.GetUtcOffset (d3).Ticks, "D12");
 132                 Assert.AreEqual(36000000000L, t1.GetUtcOffset (d4).Ticks, "D13");
 133                 Assert.AreEqual(0L, t1.GetUtcOffset (d5).Ticks, "D14");
 134
 135                 // Test TimeZone methods with UTC DateTime in DST.
 136                 DateTime d6 = d4.ToUniversalTime ();
 137                 Assert.AreEqual(false, t1.IsDaylightSavingTime (d6), "D15");
 138                 Assert.AreEqual(0, t1.GetUtcOffset (d6).Ticks, "D16");
 139         }
 140
 141         private void NZST(TimeZone t1) {
 142                 Assert.AreEqual("NZST", t1.StandardName, "E01");
 143                 Assert.AreEqual("NZDT", t1.DaylightName, "E02");
 144
 145                 DaylightTime d1 = t1.GetDaylightChanges (2013);
 146                 Assert.AreEqual("09/29/2013 02:00:00", d1.Start.ToString ("G", CultureInfo.InvariantCulture), "E03");
 147                 Assert.AreEqual("04/07/2013 03:00:00", d1.End.ToString ("G", CultureInfo.InvariantCulture), "E04");
 148                 Assert.AreEqual(36000000000L, d1.Delta.Ticks, "E05");
 149
 150                 DaylightTime d2 = t1.GetDaylightChanges (2001);
 151                 Assert.AreEqual("10/07/2001 02:00:00", d2.Start.ToString ("G", CultureInfo.InvariantCulture), "E06");
 152                 Assert.AreEqual("03/18/2001 03:00:00", d2.End.ToString ("G", CultureInfo.InvariantCulture), "E07");
 153                 Assert.AreEqual(36000000000L, d2.Delta.Ticks, "E08");
 154
 155                 DateTime d3 = new DateTime(2013,02,15);
 156                 Assert.AreEqual(true, t1.IsDaylightSavingTime (d3), "E09");
 157                 DateTime d4 = new DateTime(2013,04,30);
 158                 Assert.AreEqual(false, t1.IsDaylightSavingTime (d4), "E10");
 159                 DateTime d5 = new DateTime(2013,11,03);
 160                 Assert.AreEqual(true, t1.IsDaylightSavingTime (d5), "E11");
 161
 162                 Assert.AreEqual(36000000000L /*hour*/ * 13L, t1.GetUtcOffset (d3).Ticks, "E12");
 163                 Assert.AreEqual(36000000000L /*hour*/ * 12L, t1.GetUtcOffset (d4).Ticks, "E13");
 164                 Assert.AreEqual(36000000000L /*hour*/ * 13L, t1.GetUtcOffset (d5).Ticks, "E14");
 165
 166                 // Test TimeZone methods with UTC DateTime in DST.
 167                 DateTime d6 = d5.ToUniversalTime ();
 168                 Assert.AreEqual(false, t1.IsDaylightSavingTime (d6), "E15");
 169                 Assert.AreEqual(0, t1.GetUtcOffset (d6).Ticks, "E16");
 170         }
 171
 172         [Test]
 173         public void TestCtors ()
 174         {
 175                 TimeZone t1 = TimeZone.CurrentTimeZone;
 176                 switch (t1.StandardName) {
 177                         case "CET":
 178                                 CET (t1);
 179                                 break;
 180                         case "Eastern Standard Time":
 181                         case "EST":
 182                                 EST (t1);
 183                                 break;
 184                         case "Tokyo Standard Time":
 185                                 TST (t1);
 186                                 break;
 187                         case "GMT":
 188                                 GMT (t1);
 189                                 break;
 190                         case "NZST":
 191                                 NZST (t1);
 192                                 break;
 193                         default:
 194                                 NUnit.Framework.Assert.Ignore ("Your time zone (" + t1.StandardName + ") isn't defined in the test case");
 195                                 break;
 196                 }
 197         }
 198
 199         [Test]
 200         public void CurrentTimeZone_SerializationRoundtrip ()
 201         {
 202                 TimeZone tz = TimeZone.CurrentTimeZone;
 203                 BinaryFormatter bf = new BinaryFormatter ();
 204                 MemoryStream ms = new MemoryStream ();
 205                 bf.Serialize (ms, tz);
 206
 207                 ms.Position = 0;
 208                 TimeZone clone = (TimeZone) bf.Deserialize (ms);
 209
 210                 Assert.AreEqual (tz.DaylightName, clone.DaylightName, "DaylightName");
 211                 Assert.AreEqual (tz.StandardName, clone.StandardName, "StandardName");
 212         }
 213
 214         static private byte[] serialized_timezone = {
 215                 0x00, 0x01, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0xFF, 0xFF, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x04, 0x01, 0x00, 0x00, 0x00,
 216                 0x1C, 0x53, 0x79, 0x73, 0x74, 0x65, 0x6D, 0x2E, 0x43, 0x75, 0x72, 0x72, 0x65, 0x6E, 0x74, 0x53, 0x79, 0x73, 0x74, 0x65, 0x6D, 0x54,
 217                 0x69, 0x6D, 0x65, 0x5A, 0x6F, 0x6E, 0x65, 0x04, 0x00, 0x00, 0x00, 0x17, 0x6D, 0x5F, 0x43, 0x61, 0x63, 0x68, 0x65, 0x64, 0x44, 0x61,
 218                 0x79, 0x6C, 0x69, 0x67, 0x68, 0x74, 0x43, 0x68, 0x61, 0x6E, 0x67, 0x65, 0x73, 0x0D, 0x6D, 0x5F, 0x74, 0x69, 0x63, 0x6B, 0x73, 0x4F,
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 220                 0x5F, 0x64, 0x61, 0x79, 0x6C, 0x69, 0x67, 0x68, 0x74, 0x4E, 0x61, 0x6D, 0x65, 0x03, 0x00, 0x01, 0x01, 0x1C, 0x53, 0x79, 0x73, 0x74,
 221                 0x65, 0x6D, 0x2E, 0x43, 0x6F, 0x6C, 0x6C, 0x65, 0x63, 0x74, 0x69, 0x6F, 0x6E, 0x73, 0x2E, 0x48, 0x61, 0x73, 0x68, 0x74, 0x61, 0x62,
 222                 0x6C, 0x65, 0x09, 0x09, 0x02, 0x00, 0x00, 0x00, 0x00, 0xF8, 0x29, 0x17, 0xD6, 0xFF, 0xFF, 0xFF, 0x06, 0x03, 0x00, 0x00, 0x00, 0x15,
 223                 0x45, 0x61, 0x73, 0x74, 0x65, 0x72, 0x6E, 0x20, 0x53, 0x74, 0x61, 0x6E, 0x64, 0x61, 0x72, 0x64, 0x20, 0x54, 0x69, 0x6D, 0x65, 0x0A,
 224                 0x04, 0x02, 0x00, 0x00, 0x00, 0x1C, 0x53, 0x79, 0x73, 0x74, 0x65, 0x6D, 0x2E, 0x43, 0x6F, 0x6C, 0x6C, 0x65, 0x63, 0x74, 0x69, 0x6F,
 225                 0x6E, 0x73, 0x2E, 0x48, 0x61, 0x73, 0x68, 0x74, 0x61, 0x62, 0x6C, 0x65, 0x07, 0x00, 0x00, 0x00, 0x0A, 0x4C, 0x6F, 0x61, 0x64, 0x46,
 226                 0x61, 0x63, 0x74, 0x6F, 0x72, 0x07, 0x56, 0x65, 0x72, 0x73, 0x69, 0x6F, 0x6E, 0x08, 0x43, 0x6F, 0x6D, 0x70, 0x61, 0x72, 0x65, 0x72,
 227                 0x10, 0x48, 0x61, 0x73, 0x68, 0x43, 0x6F, 0x64, 0x65, 0x50, 0x72, 0x6F, 0x76, 0x69, 0x64, 0x65, 0x72, 0x08, 0x48, 0x61, 0x73, 0x68,
 228                 0x53, 0x69, 0x7A, 0x65, 0x04, 0x4B, 0x65, 0x79, 0x73, 0x06, 0x56, 0x61, 0x6C, 0x75, 0x65, 0x73, 0x00, 0x00, 0x03, 0x03, 0x00, 0x05,
 229                 0x05, 0x0B, 0x08, 0x1C, 0x53, 0x79, 0x73, 0x74, 0x65, 0x6D, 0x2E, 0x43, 0x6F, 0x6C, 0x6C, 0x65, 0x63, 0x74, 0x69, 0x6F, 0x6E, 0x73,
 230                 0x2E, 0x49, 0x43, 0x6F, 0x6D, 0x70, 0x61, 0x72, 0x65, 0x72, 0x24, 0x53, 0x79, 0x73, 0x74, 0x65, 0x6D, 0x2E, 0x43, 0x6F, 0x6C, 0x6C,
 231                 0x65, 0x63, 0x74, 0x69, 0x6F, 0x6E, 0x73, 0x2E, 0x49, 0x48, 0x61, 0x73, 0x68, 0x43, 0x6F, 0x64, 0x65, 0x50, 0x72, 0x6F, 0x76, 0x69,
 232                 0x64, 0x65, 0x72, 0x08, 0xEC, 0x51, 0x38, 0x3F, 0x03, 0x00, 0x00, 0x00, 0x0A, 0x0A, 0x0B, 0x00, 0x00, 0x00, 0x09, 0x04, 0x00, 0x00,
 233                 0x00, 0x09, 0x05, 0x00, 0x00, 0x00, 0x10, 0x04, 0x00, 0x00, 0x00, 0x03, 0x00, 0x00, 0x00, 0x08, 0x08, 0xCC, 0x07, 0x00, 0x00, 0x08,
 234                 0x08, 0xD5, 0x07, 0x00, 0x00, 0x08, 0x08, 0xD2, 0x07, 0x00, 0x00, 0x10, 0x05, 0x00, 0x00, 0x00, 0x03, 0x00, 0x00, 0x00, 0x09, 0x06,
 235                 0x00, 0x00, 0x00, 0x09, 0x07, 0x00, 0x00, 0x00, 0x09, 0x08, 0x00, 0x00, 0x00, 0x04, 0x06, 0x00, 0x00, 0x00, 0x21, 0x53, 0x79, 0x73,
 236                 0x74, 0x65, 0x6D, 0x2E, 0x47, 0x6C, 0x6F, 0x62, 0x61, 0x6C, 0x69, 0x7A, 0x61, 0x74, 0x69, 0x6F, 0x6E, 0x2E, 0x44, 0x61, 0x79, 0x6C,
 237                 0x69, 0x67, 0x68, 0x74, 0x54, 0x69, 0x6D, 0x65, 0x03, 0x00, 0x00, 0x00, 0x07, 0x6D, 0x5F, 0x73, 0x74, 0x61, 0x72, 0x74, 0x05, 0x6D,
 238                 0x5F, 0x65, 0x6E, 0x64, 0x07, 0x6D, 0x5F, 0x64, 0x65, 0x6C, 0x74, 0x61, 0x00, 0x00, 0x00, 0x0D, 0x0D, 0x0C, 0x00, 0x10, 0xFA, 0x0F,
 239                 0x3D, 0xF2, 0xBC, 0x88, 0x00, 0x50, 0xD5, 0xB1, 0xC1, 0x91, 0xBD, 0x88, 0x00, 0x68, 0xC4, 0x61, 0x08, 0x00, 0x00, 0x00, 0x01, 0x07,
 240                 0x00, 0x00, 0x00, 0x06, 0x00, 0x00, 0x00, 0x00, 0x50, 0x23, 0xFA, 0x07, 0x06, 0xC7, 0x88, 0x00, 0xD0, 0xE2, 0xC4, 0x0C, 0xAB, 0xC7,
 241                 0x88, 0x00, 0x68, 0xC4, 0x61, 0x08, 0x00, 0x00, 0x00, 0x01, 0x08, 0x00, 0x00, 0x00, 0x06, 0x00, 0x00, 0x00, 0x00, 0x50, 0x0C, 0x0F,
 242                 0xEF, 0xAB, 0xC3, 0x88, 0x00, 0x90, 0xE7, 0xB0, 0x73, 0x4B, 0xC4, 0x88, 0x00, 0x68, 0xC4, 0x61, 0x08, 0x00, 0x00, 0x00, 0x0B
 243         };
 244
 245         [Test]
 246         [Category ("NotWorking")]
 247         // 1.x - deserialize but strings are null
 248         // 2.x - eexception when creating a datetime with a negative value
 249         public void DeserializeKnownValue ()
 250         {
 251                 MemoryStream ms = new MemoryStream (serialized_timezone);
 252                 BinaryFormatter bf = new BinaryFormatter ();
 253                 TimeZone tz = (TimeZone) bf.Deserialize (ms);
 254                 Assert.AreEqual ("Eastern Daylight Time", tz.DaylightName, "DaylightName");
 255                 Assert.AreEqual ("Eastern Standard Time", tz.StandardName, "StandardName");
 256         }
 257
 258         [Test]
 259         public void ToLocalTimeAtDSTBoundaries ()
 260         {
 261                 TimeZone tz = TimeZone.CurrentTimeZone;
 262                 DateTime dst_start_utc = tz.GetDaylightChanges(2007).Start.ToUniversalTime ();
 263
 264                 if (dst_start_utc == DateTime.MinValue)
 265                         Assert.Ignore ("Couldn't get beginning of daylight saving time in 2007.");
 266                 Assert.IsTrue (tz.ToLocalTime (dst_start_utc.Subtract (new TimeSpan (0, 1, 0))) < tz.ToLocalTime (dst_start_utc), "0:1:59 < 0:3:00");
 267                 Assert.IsTrue (tz.ToLocalTime (dst_start_utc) < tz.ToLocalTime (dst_start_utc.Add (new TimeSpan (0, 1, 0))), "0:3:00 < 0:3:01");
 268                 Assert.IsTrue (tz.ToLocalTime (dst_start_utc.Add (new TimeSpan (0, 1, 0))) < tz.ToLocalTime (dst_start_utc.Add (new TimeSpan (0, 59, 0))), "0:3:01 < 0:3:59");
 269                 Assert.IsTrue (tz.ToLocalTime (dst_start_utc.Add (new TimeSpan (0, 59, 0))) < tz.ToLocalTime (dst_start_utc.Add (new TimeSpan (1, 0, 0))), "0:3:59 < 0:4:00");
 270                 Assert.IsTrue (tz.ToLocalTime (dst_start_utc.Add (new TimeSpan (1, 0, 0))) < tz.ToLocalTime (dst_start_utc.Add (new TimeSpan (1, 1, 0))), "0:4:00 < 0:4:01");
 271         }
 272
 273                 [Test]
 274                 public void GetUtcOffsetAtDSTBoundary ()
 275                 {
 276                         /*
 277                          * Getting a definitive list of timezones which do or don't observe Daylight
 278                          * Savings is difficult (can't say America's or USA definitively) and lengthy see
 279                          *
 280                          * http://en.wikipedia.org/wiki/Daylight_saving_time_by_country
 281                          *
 282                          * as a good starting point for a list.
 283                          *
 284                          * The following are SOME of the timezones/regions which do support daylight savings.
 285                          *
 286                          * Pacific/Auckland
 287                          * Pacific/Sydney
 288                          * USA (EST, CST, MST, PST, AKST) note this does not cover all states or regions
 289                          * Europe/London (GMT)
 290                          * CET (member states of the European Union)
 291                          *
 292                          * This test should work in all the above timezones
 293                          */
 294
 295
 296                         TimeZone tz = TimeZone.CurrentTimeZone;
 297                         int year = DateTime.Now.Year;
 298                         DaylightTime daylightChanges = tz.GetDaylightChanges(year);
 299                         DateTime dst_end = daylightChanges.End;
 300
 301                         if (dst_end == DateTime.MinValue)
 302                                 Assert.Ignore (tz.StandardName + " did not observe daylight saving time during " + year + ".");
 303
 304                         var standardOffset = tz.GetUtcOffset(daylightChanges.Start.AddMinutes(-1));
 305
 306                         Assert.AreEqual(standardOffset, tz.GetUtcOffset (dst_end));
 307                         Assert.AreEqual(standardOffset, tz.GetUtcOffset (dst_end.Add (daylightChanges.Delta.Negate ().Add (TimeSpan.FromSeconds(1)))));
 308                         Assert.AreEqual(standardOffset, tz.GetUtcOffset (dst_end.Add(daylightChanges.Delta.Negate ())));
 309                         Assert.AreNotEqual(standardOffset, tz.GetUtcOffset (dst_end.Add(daylightChanges.Delta.Negate ().Add (TimeSpan.FromSeconds(-1)))));
 310                 }
 311
 312
 313                 [Test]
 314                 public void StaticProperties ()
 315                 {
 316                         Assert.IsNotNull (TimeZoneInfo.Local, "Local");
 317                         Assert.IsNotNull (TimeZoneInfo.Utc, "Utc");
 318                 }
 319
 320                 [Test]
 321                 public void FindSystemTimeZoneById ()
 322                 {
 323                         TimeZoneInfo tzi = TimeZoneInfo.FindSystemTimeZoneById ("Canada/Eastern");
 324                         Assert.AreEqual ("EDT", tzi.DaylightName, "DaylightName");
 325                         Assert.AreEqual ("EST", tzi.StandardName, "StandardName");
 326                         Assert.IsTrue (tzi.SupportsDaylightSavingTime, "SupportsDaylightSavingTime");
 327                 }
 328
 329 #if MOBILE
 330                 // On device we cannot read the OS file system to look for /etc/localtime
 331                 // and /usr/share/zoneinfo - so we must initialize the BCL TimeZoneInfo
 332                 // from NSTimeZoneInfo. The tests here check the code paths between the
 333                 // two types - if they break then TimeZoneInfo work work at all
 334                 // ref: http://bugzilla.xamarin.com/show_bug.cgi?id=1790
 335
 336                 bool incomplete_data_on_simulator_only_bug;
 337
 338                 [Test]
 339                 public void GetSystemTimeZones ()
 340                 {
 341                         // if test is executed a second time then it report less than 400 (about 127) items available
 342                         if (incomplete_data_on_simulator_only_bug)
 343                                 Assert.Ignore ("known to fail on some iOS simulator versions - see source comments");
 344
 345                         try {
 346                                 Assert.That (TimeZoneInfo.GetSystemTimeZones ().Count, Is.GreaterThan (400), "GetSystemTimeZones");
 347                         } catch (NullReferenceException) {
 348                                 // that's a weird one. It failed on iOS 5.1 *beta* simulator (on Lion) but it worked on *final*
 349                                 // now it fails on Snow Leopard the same way (incomplete data) with iOS5 simulator (OS update ?)
 350                                 // but it *never*ever* failed on devices
 351                                 incomplete_data_on_simulator_only_bug = true;
 352 #if XAMCORE_2_0
 353                                 if (ObjCRuntime.Runtime.Arch == ObjCRuntime.Arch.SIMULATOR)
 354 #else
 355                                 if (MonoTouch.ObjCRuntime.Runtime.Arch == MonoTouch.ObjCRuntime.Arch.SIMULATOR)
 356 #endif
 357                                         Assert.Ignore ("known to fail on some iOS simulator versions - see source comments");
 358                         }
 359                 }
 360 #endif
 361         }
 362 }