Allow GetDateTime to read a string as a DateTime. Fixes #980

bgrainger · bgrainger · commit 876514b98182 · 2021-07-02T14:30:39.000-07:00
diff --git a/src/MySqlConnector/Core/Row.cs b/src/MySqlConnector/Core/Row.cs
@@ -2,6 +2,7 @@
 using System.Buffers.Text;
 using System.IO;
 using System.Runtime.InteropServices;
+using System.Text;
 using MySqlConnector.Protocol;
 using MySqlConnector.Protocol.Payloads;
 using MySqlConnector.Utilities;
@@ -353,6 +354,16 @@ public ulong GetUInt64(int ordinal)
 		public DateTime GetDateTime(int ordinal)
 		{
 			var value = GetValue(ordinal);
+
+			if (value is string dateString)
+			{
+				// slightly inefficient to roundtrip the bytes through a string, but this is assumed to be an infrequent code path; this could be optimised to reprocess the original bytes
+				if (dateString.Length is >= 10 and <= 26)
+					value = ParseDateTime(Encoding.UTF8.GetBytes(dateString));
+				else
+					throw new FormatException("Couldn't interpret '{0}' as a valid DateTime".FormatInvariant(value));
+			}
+
 			if (value is MySqlDateTime mySqlDateTime)
 				return mySqlDateTime.GetDateTime();
 			return (DateTime) value;
@@ -462,6 +473,82 @@ protected Row(ResultSet resultSet)
 		protected ResultSet ResultSet { get; }
 		protected MySqlConnection Connection => ResultSet.Connection;
 
+		protected object ParseDateTime(ReadOnlySpan<byte> value)
+		{
+			Exception? exception = null;
+			if (!Utf8Parser.TryParse(value, out int year, out var bytesConsumed) || bytesConsumed != 4)
+				goto InvalidDateTime;
+			if (value.Length < 5 || value[4] != 45)
+				goto InvalidDateTime;
+			if (!Utf8Parser.TryParse(value.Slice(5), out int month, out bytesConsumed) || bytesConsumed != 2)
+				goto InvalidDateTime;
+			if (value.Length < 8 || value[7] != 45)
+				goto InvalidDateTime;
+			if (!Utf8Parser.TryParse(value.Slice(8), out int day, out bytesConsumed) || bytesConsumed != 2)
+				goto InvalidDateTime;
+
+			if (year == 0 && month == 0 && day == 0)
+			{
+				if (Connection.ConvertZeroDateTime)
+					return DateTime.MinValue;
+				if (Connection.AllowZeroDateTime)
+					return new MySqlDateTime();
+				throw new InvalidCastException("Unable to convert MySQL date/time to System.DateTime, set AllowZeroDateTime=True or ConvertZeroDateTime=True in the connection string. See https://mysqlconnector.net/connection-options/");
+			}
+
+			int hour, minute, second, microseconds;
+			if (value.Length == 10)
+			{
+				hour = 0;
+				minute = 0;
+				second = 0;
+				microseconds = 0;
+			}
+			else
+			{
+				if (value[10] != 32)
+					goto InvalidDateTime;
+				if (!Utf8Parser.TryParse(value.Slice(11), out hour, out bytesConsumed) || bytesConsumed != 2)
+					goto InvalidDateTime;
+				if (value.Length < 14 || value[13] != 58)
+					goto InvalidDateTime;
+				if (!Utf8Parser.TryParse(value.Slice(14), out minute, out bytesConsumed) || bytesConsumed != 2)
+					goto InvalidDateTime;
+				if (value.Length < 17 || value[16] != 58)
+					goto InvalidDateTime;
+				if (!Utf8Parser.TryParse(value.Slice(17), out second, out bytesConsumed) || bytesConsumed != 2)
+					goto InvalidDateTime;
+
+				if (value.Length == 19)
+				{
+					microseconds = 0;
+				}
+				else
+				{
+					if (value[19] != 46)
+						goto InvalidDateTime;
+
+					if (!Utf8Parser.TryParse(value.Slice(20), out microseconds, out bytesConsumed) || bytesConsumed != value.Length - 20)
+						goto InvalidDateTime;
+					for (; bytesConsumed < 6; bytesConsumed++)
+						microseconds *= 10;
+				}
+			}
+
+			try
+			{
+				return Connection.AllowZeroDateTime ? (object) new MySqlDateTime(year, month, day, hour, minute, second, microseconds) :
+					new DateTime(year, month, day, hour, minute, second, microseconds / 1000, Connection.DateTimeKind).AddTicks(microseconds % 1000 * 10);
+			}
+			catch (Exception ex)
+			{
+				exception = ex;
+			}
+
+InvalidDateTime:
+			throw new FormatException("Couldn't interpret '{0}' as a valid DateTime".FormatInvariant(Encoding.UTF8.GetString(value)), exception);
+		}
+
 		protected unsafe static Guid CreateGuidFromBytes(MySqlGuidFormat guidFormat, ReadOnlySpan<byte> bytes) =>
 			guidFormat switch
 			{
diff --git a/src/MySqlConnector/Core/TextRow.cs b/src/MySqlConnector/Core/TextRow.cs
@@ -128,81 +128,5 @@ private static uint ParseUInt32(ReadOnlySpan<byte> data) =>
 
 		private static long ParseInt64(ReadOnlySpan<byte> data) =>
 			!Utf8Parser.TryParse(data, out long value, out var bytesConsumed) || bytesConsumed != data.Length ? throw new FormatException() : value;
-
-		private object ParseDateTime(ReadOnlySpan<byte> value)
-		{
-			Exception? exception = null;
-			if (!Utf8Parser.TryParse(value, out int year, out var bytesConsumed) || bytesConsumed != 4)
-				goto InvalidDateTime;
-			if (value.Length < 5 || value[4] != 45)
-				goto InvalidDateTime;
-			if (!Utf8Parser.TryParse(value.Slice(5), out int month, out bytesConsumed) || bytesConsumed != 2)
-				goto InvalidDateTime;
-			if (value.Length < 8 || value[7] != 45)
-				goto InvalidDateTime;
-			if (!Utf8Parser.TryParse(value.Slice(8), out int day, out bytesConsumed) || bytesConsumed != 2)
-				goto InvalidDateTime;
-
-			if (year == 0 && month == 0 && day == 0)
-			{
-				if (Connection.ConvertZeroDateTime)
-					return DateTime.MinValue;
-				if (Connection.AllowZeroDateTime)
-					return new MySqlDateTime();
-				throw new InvalidCastException("Unable to convert MySQL date/time to System.DateTime, set AllowZeroDateTime=True or ConvertZeroDateTime=True in the connection string. See https://mysqlconnector.net/connection-options/");
-			}
-
-			int hour, minute, second, microseconds;
-			if (value.Length == 10)
-			{
-				hour = 0;
-				minute = 0;
-				second = 0;
-				microseconds = 0;
-			}
-			else
-			{
-				if (value[10] != 32)
-					goto InvalidDateTime;
-				if (!Utf8Parser.TryParse(value.Slice(11), out hour, out bytesConsumed) || bytesConsumed != 2)
-					goto InvalidDateTime;
-				if (value.Length < 14 || value[13] != 58)
-					goto InvalidDateTime;
-				if (!Utf8Parser.TryParse(value.Slice(14), out minute, out bytesConsumed) || bytesConsumed != 2)
-					goto InvalidDateTime;
-				if (value.Length < 17 || value[16] != 58)
-					goto InvalidDateTime;
-				if (!Utf8Parser.TryParse(value.Slice(17), out second, out bytesConsumed) || bytesConsumed != 2)
-					goto InvalidDateTime;
-
-				if (value.Length == 19)
-				{
-					microseconds = 0;
-				}
-				else
-				{
-					if (value[19] != 46)
-						goto InvalidDateTime;
-
-					if (!Utf8Parser.TryParse(value.Slice(20), out microseconds, out bytesConsumed) || bytesConsumed != value.Length - 20)
-						goto InvalidDateTime;
-					for (; bytesConsumed < 6; bytesConsumed++)
-						microseconds *= 10;
-				}
-			}
-
-			try
-			{
-				return Connection.AllowZeroDateTime ? (object) new MySqlDateTime(year, month, day, hour, minute, second, microseconds) :
-					new DateTime(year, month, day, hour, minute, second, microseconds / 1000, Connection.DateTimeKind).AddTicks(microseconds % 1000 * 10);
-			}
-			catch (Exception ex)
-			{
-				exception = ex;
-			}
-
-			InvalidDateTime:
-			throw new FormatException("Couldn't interpret '{0}' as a valid DateTime".FormatInvariant(Encoding.UTF8.GetString(value)), exception);
-		}
 	}
 }
diff --git a/tests/SideBySide/DataTypes.cs b/tests/SideBySide/DataTypes.cs
@@ -984,6 +984,74 @@ public void ReadNewDate(bool prepare)
 			}
 		}
 
+		[Theory]
+		[InlineData("Date", false, "9999 12 31")]
+		[InlineData("Date", true, "9999 12 31")]
+		[InlineData("DateTime", false, "9999 12 31 23 59 59 999999")]
+		[InlineData("DateTime", true, "9999 12 31 23 59 59 999999")]
+		[InlineData("Time", false, null)]
+		[InlineData("Time", true, null)]
+		public void ReadVarCharFromNestedQueryAsDate(string columnName, bool prepare, string expectedValue)
+		{
+			var expectedDate = (DateTime?) ConvertToDateTime(new object[] { expectedValue }, DateTimeKind.Unspecified)[0];
+
+			// returns VARCHAR in MySQL 5.7; DATE in MySQL 8.0
+			using var cmd = new MySqlCommand($@"SELECT MAX(CASE WHEN 1 = t.`Key` THEN t.`{columnName}` END) AS `Max`
+FROM (SELECT `{columnName}`, 1 AS `Key` FROM datatypes_times) t
+GROUP BY t.`Key`
+ORDER BY t.`Key`", Connection);
+			if (prepare)
+				cmd.Prepare();
+
+			using var reader = cmd.ExecuteReader();
+			Assert.True(reader.Read());
+			if (expectedDate.HasValue)
+				Assert.Equal(expectedDate.Value, reader.GetDateTime(0));
+			else
+				Assert.ThrowsAny<Exception>(() => reader.GetDateTime(0));
+		}
+
+		[Theory]
+#if !BASELINE
+		[InlineData("1001-02", false, null)]
+		[InlineData("1001-02", true, null)]
+		[InlineData("2000-01-02 03-04-05", true, null)]
+		[InlineData("2000-01-02 18:19:20.9876543", false, null)]
+		[InlineData("2000-01-02 18:19:20.9876543", true, null)]
+		[InlineData("2000-01-02 03-04-05 123456", false, null)]
+#endif
+		[InlineData("1001-02-03", false, "1001 2 3")]
+		[InlineData("1001-02-0A", true, null)]
+		[InlineData("2000-01-02 03:04:05", false, "2000 1 2 3 4 5")]
+		[InlineData("2000-01-02T03:04:05", false, null)]
+		[InlineData("2000-01-02 2003-04-05", true, null)]
+		[InlineData("2000-01-02 18:19:20.9", true, "2000 1 2 18 19 20 900000")]
+		[InlineData("2000-01-02 18:19:20.98", false, "2000 1 2 18 19 20 980000")]
+		[InlineData("2000-01-02 18:19:20.987", true, "2000 1 2 18 19 20 987000")]
+		[InlineData("2000-01-02 18:19:20.9876", false, "2000 1 2 18 19 20 987600")]
+		[InlineData("2000-01-02 18:19:20.98765", true, "2000 1 2 18 19 20 987650")]
+		[InlineData("2000-01-02 18:19:20.987654", false, "2000 1 2 18 19 20 987654")]
+		public void ReadVarCharAsDate(string value, bool prepare, string expectedValue)
+		{
+			var expectedDate = (DateTime?) ConvertToDateTime(new object[] { expectedValue }, DateTimeKind.Unspecified)[0];
+
+			// returns VARCHAR in MySQL 5.7; DATE in MySQL 8.0
+			using var cmd = new MySqlCommand($@"SELECT '{value}' AS value", Connection);
+			if (prepare)
+				cmd.Prepare();
+
+			using var reader = cmd.ExecuteReader();
+			Assert.True(reader.Read());
+			if (expectedDate.HasValue)
+				Assert.Equal(expectedDate.Value, reader.GetDateTime(0));
+			else
+#if BASELINE
+				Assert.ThrowsAny<Exception>(() => reader.GetDateTime(0));
+#else
+				Assert.Throws<FormatException>(() => reader.GetDateTime(0));
+#endif
+		}
+
 		[Theory]
 		[InlineData("Geometry", "GEOMETRY", new byte[] { 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 240, 63, 0, 0, 0, 0, 0, 0, 240, 63 })]
 		[InlineData("Point", "GEOMETRY", new byte[] { 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 240, 63, 0, 0, 0, 0, 0, 0, 240, 63 })]
@@ -1717,8 +1785,7 @@ private static object[] ConvertToTimeSpan(object[] input)
 
 		private static int[] SplitAndParse(object obj)
 		{
-			var value = obj as string;
-			if (value is null)
+			if (obj is not string value)
 				return null;
 
 			var split = value.Split();
