Add tests for Core; fix found issues

SabreTools.Core.Test/Tools/DateTimeHelperTests.cs

@@ -0,0 +1,65 @@
+using System;
+using SabreTools.Core.Tools;
+using Xunit;
+
+namespace SabreTools.Core.Test.Tools
+{
+    public class DateTimeHelperTests
+    {
+        #region ConvertToMsDosTimeFormat
+
+        [Fact]
+        public void ConvertToMsDosTimeFormat_MinSupported()
+        {
+            long expected = 2162688;
+            DateTime dateTime = new DateTime(1980, 01, 01, 00, 00, 00, 00);
+            long actual =  DateTimeHelper.ConvertToMsDosTimeFormat(dateTime);
+            Assert.Equal(expected, actual);
+        }
+
+        [Fact]
+        public void ConvertToMsDosTimeFormat_Y2K()
+        {
+            long expected = 673251328;
+            DateTime dateTime = new DateTime(2000, 01, 01, 00, 00, 00, 00);
+            long actual =  DateTimeHelper.ConvertToMsDosTimeFormat(dateTime);
+            Assert.Equal(expected, actual);
+        }
+
+        #endregion
+
+        #region ConvertFromMsDosTimeFormat
+
+        [Fact]
+        public void ConvertFromMsDosTimeFormat_MinSupported()
+        {
+            uint msDosDateTime = 2162688;
+            DateTime actual =  DateTimeHelper.ConvertFromMsDosTimeFormat(msDosDateTime);
+
+            Assert.Equal(1980, actual.Year);
+            Assert.Equal(01, actual.Month);
+            Assert.Equal(01, actual.Day);
+            Assert.Equal(00, actual.Hour);
+            Assert.Equal(00, actual.Minute);
+            Assert.Equal(00, actual.Second);
+            Assert.Equal(000, actual.Millisecond);
+        }
+
+        [Fact]
+        public void ConvertFromMsDosTimeFormat_Y2K()
+        {
+            uint msDosDateTime = 673251328;
+            DateTime actual =  DateTimeHelper.ConvertFromMsDosTimeFormat(msDosDateTime);
+
+            Assert.Equal(2000, actual.Year);
+            Assert.Equal(01, actual.Month);
+            Assert.Equal(01, actual.Day);
+            Assert.Equal(00, actual.Hour);
+            Assert.Equal(00, actual.Minute);
+            Assert.Equal(00, actual.Second);
+            Assert.Equal(000, actual.Millisecond);
+        }
+
+        #endregion
+    }
+}