Populate MySqlException.Data. Fixes #602

Author: bgrainger

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

@@ -1,4 +1,5 @@
 using System;
+using System.Collections;
 using System.Data.Common;
 #if !NETSTANDARD1_3
 using System.Runtime.Serialization;
@@ -30,6 +31,20 @@ public override void GetObjectData(SerializationInfo info, StreamingContext cont
 		}
 #endif
 
+		public override IDictionary Data
+		{
+			get
+			{
+				if (m_data == null)
+				{
+					m_data = base.Data;
+					m_data["Server Error Code"] = Number;
+					m_data["SqlState"] = SqlState;
+				}
+				return m_data;
+			}
+		}
+
 		internal MySqlException(string message)
 			: this(message, null)
 		{
@@ -56,5 +71,7 @@ internal MySqlException(int errorNumber, string sqlState, string message, Except
 
 		internal static MySqlException CreateForTimeout(Exception innerException) =>
 			new MySqlException((int) MySqlErrorCode.CommandTimeoutExpired, null, "The Command Timeout expired before the operation completed.", innerException);
+
+		IDictionary m_data;
 	}
 }

tests/MySqlConnector.Tests/MySqlExceptionTests.cs

@@ -25,5 +25,13 @@ public void IsSerializable()
 			Assert.Equal(exception.SqlState, copy.SqlState);
 			Assert.Equal(exception.Message, copy.Message);
 		}
+
+		[Fact]
+		public void Data()
+		{
+			var exception = new MySqlException(1, "two", "three");
+			Assert.Equal(1, exception.Data["Server Error Code"]);
+			Assert.Equal("two", exception.Data["SqlState"]);
+		}
 	}
 }

tests/SideBySide/ConnectAsync.cs

@@ -34,6 +34,7 @@ public async Task ConnectBadHost()
 				catch (MySqlException ex)
 				{
 					Assert.Equal((int) MySqlErrorCode.UnableToConnectToHost, ex.Number);
+					Assert.Equal((int) MySqlErrorCode.UnableToConnectToHost, ex.Data["Server Error Code"]);
 				}
 				Assert.Equal(ConnectionState.Closed, connection.State);
 			}

tests/SideBySide/ConnectSync.cs

@@ -32,6 +32,7 @@ public void ConnectBadHost()
 				catch (MySqlException ex)
 				{
 					Assert.Equal((int) MySqlErrorCode.UnableToConnectToHost, ex.Number);
+					Assert.Equal((int) MySqlErrorCode.UnableToConnectToHost, ex.Data["Server Error Code"]);
 				}
 				Assert.Equal(ConnectionState.Closed, connection.State);
 			}