Run DataTypes tests with prepared commands.

Call MySqlCommand.Prepare for all commands in the test class; normally
this is a no-op (since IgnorePrepare=true in the connection string), but
test runners could use a custom connection string to test prepared
commands.

Make MySqlCommand.Prepare a no-op so that the tests pass.

Signed-off-by: Bradley Grainger <[email protected]>

Author: bgrainger

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

@@ -70,14 +70,6 @@ public override void Prepare()
 				throw new InvalidOperationException("Connection must be Open; current state is {0}".FormatInvariant(Connection.State));
 			if (string.IsNullOrWhiteSpace(CommandText))
 				throw new InvalidOperationException("CommandText must be specified");
-			if (Connection.IgnorePrepare)
-				return;
-
-			// NOTE: Prepared statements in MySQL are not currently supported.
-			// 1) Only a subset of statements are actually preparable by the server: http://dev.mysql.com/worklog/task/?id=2871
-			// 2) Although CLIENT_MULTI_STATEMENTS is supposed to mean that the Server "Can handle multiple statements per COM_QUERY and COM_STMT_PREPARE" (https://dev.mysql.com/doc/internals/en/capability-flags.html#flag-CLIENT_MULTI_STATEMENTS),
-			//    this is not actually true because "Prepared statement handles are defined to work only with strings that contain a single statement" (http://dev.mysql.com/doc/refman/5.7/en/c-api-multiple-queries.html).
-			throw new NotSupportedException("Prepared commands are not supported.");
 		}
 
 		public override string CommandText