Add MySqlDataReader.GetTimeSpan. Fixes #438

Author: bgrainger

src/MySqlConnector/MySql.Data.MySqlClient/MySqlDataReader.cs

@@ -223,6 +223,9 @@ public override long GetChars(int ordinal, long dataOffset, char[] buffer, int b
 		public DateTimeOffset GetDateTimeOffset(int ordinal) => GetResultSet().GetCurrentRow().GetDateTimeOffset(ordinal);
 		public DateTimeOffset GetDateTimeOffset(string name) => GetDateTimeOffset(GetOrdinal(name));
 
+		public TimeSpan GetTimeSpan(int ordinal) => (TimeSpan) GetValue(ordinal);
+		public TimeSpan GetTimeSpan(string name) => GetTimeSpan(GetOrdinal(name));
+
 		public override string GetString(int ordinal) => GetResultSet().GetCurrentRow().GetString(ordinal);
 		public string GetString(string name) => GetString(GetOrdinal(name));
 

tests/SideBySide/DataTypes.cs

@@ -477,7 +477,7 @@ public void QueryZeroDateTime(bool convertZeroDateTime)
 		[InlineData("`Time`", "TIME", new object[] { null, "-838 -59 -59", "838 59 59", "0 0 0", "0 14 3 4 567890" })]
 		public void QueryTime(string column, string dataTypeName, object[] expected)
 		{
-			DoQuery<InvalidCastException>("times", column, dataTypeName, ConvertToTimeSpan(expected), reader => reader.GetFieldValue<TimeSpan>(0));
+			DoQuery("times", column, dataTypeName, ConvertToTimeSpan(expected), reader => reader.GetTimeSpan(0));
 		}
 
 		[Theory]