Make MySqlException serializable. Fixes #601

Author: bgrainger

docs/content/tutorials/migrating-from-connector-net.md

@@ -146,3 +146,4 @@ The following bugs in Connector/NET are fixed by switching to MySqlConnector. (~
 * [#93220](https://bugs.mysql.com/bug.php?id=93220): Can’t call FUNCTION when parameter name contains parentheses
 * [#93370](https://bugs.mysql.com/bug.php?id=93370): `MySqlParameterCollection.Add` precondition check isn't consistent
 * [#93374](https://bugs.mysql.com/bug.php?id=93374): `MySqlDataReader.GetStream` throws `IndexOutOfRangeException`
+* [#93825](https://bugs.mysql.com/bug.php?id=93825): `MySqlException` loses data when serialized

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

@@ -1,13 +1,35 @@
 using System;
 using System.Data.Common;
+#if !NETSTANDARD1_3
+using System.Runtime.Serialization;
+#endif
 
 namespace MySql.Data.MySqlClient
 {
+#if !NETSTANDARD1_3
+	[Serializable]
+#endif
 	public sealed class MySqlException : DbException
 	{
 		public int Number { get; }
 		public string SqlState { get; }
 
+#if !NETSTANDARD1_3
+		private MySqlException(SerializationInfo info, StreamingContext context)
+			: base(info, context)
+		{
+			Number = info.GetInt32("Number");
+			SqlState = info.GetString("SqlState");
+		}
+
+		public override void GetObjectData(SerializationInfo info, StreamingContext context)
+		{
+			base.GetObjectData(info, context);
+			info.AddValue("Number", Number);
+			info.AddValue("SqlState", SqlState);
+		}
+#endif
+
 		internal MySqlException(string message)
 			: this(message, null)
 		{

tests/MySqlConnector.Tests/MySqlConnector.Tests.csproj

@@ -32,7 +32,7 @@
 
   <ItemGroup Condition=" '$(Configuration)' == 'Baseline' ">
     <PackageReference Include="MySql.Data" Version="8.0.13" />
-    <Compile Remove="ByteBufferWriterTests.cs;CachedProcedureTests.cs;ConnectionTests.cs;FakeMySqlServer.cs;FakeMySqlServerConnection.cs;LoadBalancerTests.cs;NormalizeTests.cs;StatementPreparerTests.cs;TypeMapperTests.cs;UtilityTests.cs" />
+    <Compile Remove="ByteBufferWriterTests.cs;CachedProcedureTests.cs;ConnectionTests.cs;FakeMySqlServer.cs;FakeMySqlServerConnection.cs;LoadBalancerTests.cs;MySqlExceptionTests.cs;NormalizeTests.cs;StatementPreparerTests.cs;TypeMapperTests.cs;UtilityTests.cs" />
   </ItemGroup>
 
   <ItemGroup Condition=" '$(TargetFramework)' == 'net462' ">

tests/MySqlConnector.Tests/MySqlExceptionTests.cs

@@ -0,0 +1,29 @@
+using System.IO;
+using System.Runtime.Serialization.Formatters.Binary;
+using MySql.Data.MySqlClient;
+using Xunit;
+
+namespace MySqlConnector.Tests
+{
+	public class MySqlExceptionTests
+	{
+		[Fact]
+		public void IsSerializable()
+		{
+			var exception = new MySqlException(1, "two", "three");
+			MySqlException copy;
+
+			using (var stream = new MemoryStream())
+			{
+				var formatter = new BinaryFormatter();
+				formatter.Serialize(stream, exception);
+				stream.Position = 0;
+				copy = (MySqlException) formatter.Deserialize(stream);
+			}
+
+			Assert.Equal(exception.Number, copy.Number);
+			Assert.Equal(exception.SqlState, copy.SqlState);
+			Assert.Equal(exception.Message, copy.Message);
+		}
+	}
+}