Use 'is null' to test for null.

Author: bgrainger

src/MySqlConnector.Logging.Microsoft.Extensions.Logging/MicrosoftExtensionsLoggingLoggerProvider.cs

@@ -18,7 +18,7 @@ private class MicrosoftExtensionsLoggingLogger : IMySqlConnectorLogger
 
 			public void Log(MySqlConnectorLogLevel level, string message, object[] args = null, Exception exception = null)
 			{
-				if (args == null || args.Length == 0)
+				if (args is null || args.Length == 0)
 					m_logger.Log(GetLevel(level), 0, message, exception, s_getMessage);
 				else
 					m_logger.Log(GetLevel(level), 0, (message, args), exception, s_messageFormatter);

src/MySqlConnector.Logging.Serilog/SerilogLoggerProvider.cs

@@ -26,7 +26,7 @@ public SerilogLogger(string name)
 
             public void Log(MySqlConnectorLogLevel level, string message, object[] args = null, Exception exception = null)
             {
-                if (args == null || args.Length == 0)
+                if (args is null || args.Length == 0)
                     m_logger.Write(GetLevel(level), exception, message);
                 else
                 {

src/MySqlConnector.Logging.log4net/Log4netLoggerProvider.cs

@@ -21,7 +21,7 @@ private class Log4netLogger : IMySqlConnectorLogger
 
 			public void Log(MySqlConnectorLogLevel level, string message, object[] args = null, Exception exception = null)
 			{
-				if (args == null || args.Length == 0)
+				if (args is null || args.Length == 0)
 					m_logger.Log(s_loggerType, GetLevel(level), message, exception);
 				else
 					m_logger.Log(s_loggerType, GetLevel(level), string.Format(CultureInfo.InvariantCulture, message, args), exception);

src/MySqlConnector/Core/ConnectionPool.cs

@@ -214,7 +214,7 @@ public async Task ReapAsync(IOBehavior ioBehavior, CancellationToken cancellatio
 		public Dictionary<string, CachedProcedure> GetProcedureCache()
 		{
 			var procedureCache = m_procedureCache;
-			if (procedureCache == null)
+			if (procedureCache is null)
 			{
 				var newProcedureCache = new Dictionary<string, CachedProcedure>();
 				procedureCache = Interlocked.CompareExchange(ref m_procedureCache, newProcedureCache, null) ?? newProcedureCache;
@@ -290,7 +290,7 @@ private async Task CleanPoolAsync(IOBehavior ioBehavior, Func<ServerSession, boo
 								m_sessions.RemoveLast();
 							}
 						}
-						if (session == null)
+						if (session is null)
 							return;
 
 						if (shouldCleanFn(session))

src/MySqlConnector/Core/DbTypeMapping.cs

@@ -19,7 +19,7 @@ public object DoConversion(object obj)
 		{
 			if (obj.GetType() == ClrType)
 				return obj;
-			return m_convert == null ? Convert.ChangeType(obj, ClrType) : m_convert(obj);
+			return m_convert is null ? Convert.ChangeType(obj, ClrType) : m_convert(obj);
 		}
 
 		readonly Func<object, object> m_convert;

src/MySqlConnector/Core/NormalizedSchema.cs

@@ -16,9 +16,9 @@ internal sealed class NormalizedSchema
 		internal static NormalizedSchema MustNormalize(string name, string defaultSchema = null)
 		{
 			var normalized = new NormalizedSchema(name, defaultSchema);
-			if (normalized.Component == null)
+			if (normalized.Component is null)
 				throw new ArgumentException("Could not determine function/procedure name", nameof(name));
-			if (normalized.Schema == null)
+			if (normalized.Schema is null)
 				throw new ArgumentException("Could not determine schema", nameof(defaultSchema));
 			return normalized;
 		}
@@ -38,12 +38,12 @@ public NormalizedSchema(string name, string defaultSchema=null)
 					firstGroup = match.Groups[1].Value.Trim();
 				else if (match.Groups[2].Success)
 					firstGroup = match.Groups[2].Value.Trim();
-				if (Component == null)
+				if (Component is null)
 					Component = firstGroup.Trim();
 				else
 					Schema = firstGroup.Trim();
 
-				if (Schema == null)
+				if (Schema is null)
 					Schema = defaultSchema;
 			}
 		}

src/MySqlConnector/Core/PreparedStatementCommandExecutor.cs

@@ -80,7 +80,7 @@ private PayloadData CreateQueryPayload(PreparedStatement preparedStatement, MySq
 				for (var i = 0; i < parameters.Length; i++)
 				{
 					var parameter = parameters[i];
-					if (parameter.Value == null || parameter.Value == DBNull.Value)
+					if (parameter.Value is null || parameter.Value == DBNull.Value)
 						nullBitmap |= (byte) (1 << (i % 8));
 
 					if (i % 8 == 7)

src/MySqlConnector/Core/ResultSet.cs

@@ -174,7 +174,7 @@ public async Task<bool> ReadAsync(IOBehavior ioBehavior, CancellationToken cance
 				? m_readBuffer.Dequeue()
 				: await ScanRowAsync(ioBehavior, m_row, cancellationToken).ConfigureAwait(false);
 
-			if (m_row == null)
+			if (m_row is null)
 			{
 				State = BufferState;
 				return false;
@@ -187,7 +187,7 @@ public async Task<Row> BufferReadAsync(IOBehavior ioBehavior, CancellationToken
 		{
 			m_rowBuffered = m_rowBuffered?.Clone();
 			// ScanRowAsync sets m_rowBuffered to the next row if there is one
-			if (await ScanRowAsync(ioBehavior, null, cancellationToken).ConfigureAwait(false) == null)
+			if (await ScanRowAsync(ioBehavior, null, cancellationToken).ConfigureAwait(false) is null)
 				return null;
 			m_readBuffer.Enqueue(m_rowBuffered);
 			return m_rowBuffered;
@@ -245,7 +245,7 @@ Row ScanRowAsyncRemainder(PayloadData payload, Row row_)
 					}
 				}
 
-				if (row_ == null)
+				if (row_ is null)
 					row_ = DataReader.ResultSetProtocol == ResultSetProtocol.Binary ? (Row) new BinaryRow(this) : new TextRow(this);
 				row_.SetData(payload.ArraySegment);
 				m_rowBuffered = row_;
@@ -259,7 +259,7 @@ Row ScanRowAsyncRemainder(PayloadData payload, Row row_)
 
 		public string GetName(int ordinal)
 		{
-			if (ColumnDefinitions == null)
+			if (ColumnDefinitions is null)
 				throw new InvalidOperationException("There is no current result set.");
 			if (ordinal < 0 || ordinal >= ColumnDefinitions.Length)
 				throw new IndexOutOfRangeException("value must be between 0 and {0}".FormatInvariant(ColumnDefinitions.Length - 1));
@@ -268,7 +268,7 @@ public string GetName(int ordinal)
 
 		public string GetDataTypeName(int ordinal)
 		{
-			if (ColumnDefinitions == null)
+			if (ColumnDefinitions is null)
 				throw new InvalidOperationException("There is no current result set.");
 			if (ordinal < 0 || ordinal >= ColumnDefinitions.Length)
 				throw new IndexOutOfRangeException("value must be between 0 and {0}.".FormatInvariant(ColumnDefinitions.Length));
@@ -281,7 +281,7 @@ public string GetDataTypeName(int ordinal)
 
 		public Type GetFieldType(int ordinal)
 		{
-			if (ColumnDefinitions == null)
+			if (ColumnDefinitions is null)
 				throw new InvalidOperationException("There is no current result set.");
 			if (ordinal < 0 || ordinal >= ColumnDefinitions.Length)
 				throw new IndexOutOfRangeException("value must be between 0 and {0}.".FormatInvariant(ColumnDefinitions.Length));
@@ -306,9 +306,9 @@ public bool HasRows
 
 		public int GetOrdinal(string name)
 		{
-			if (name == null)
+			if (name is null)
 				throw new ArgumentNullException(nameof(name));
-			if (ColumnDefinitions == null)
+			if (ColumnDefinitions is null)
 				throw new InvalidOperationException("There is no current result set.");
 
 			for (var column = 0; column < ColumnDefinitions.Length; column++)

src/MySqlConnector/Core/Row.cs

@@ -13,7 +13,7 @@ internal abstract class Row
 		public void SetData(ArraySegment<byte> data)
 		{
 			m_data = data;
-			if (m_dataOffsets == null)
+			if (m_dataOffsets is null)
 			{
 				m_dataOffsets = new int[ResultSet.ColumnDefinitions.Length];
 				m_dataLengths = new int[ResultSet.ColumnDefinitions.Length];
@@ -76,7 +76,7 @@ public long GetBytes(int ordinal, long dataOffset, byte[] buffer, int bufferOffs
 		{
 			CheckBinaryColumn(ordinal);
 
-			if (buffer == null)
+			if (buffer is null)
 			{
 				// this isn't required by the DbDataReader.GetBytes API documentation, but is what mysql-connector-net does
 				// (as does SqlDataReader: http://msdn.microsoft.com/en-us/library/system.data.sqlclient.sqldatareader.getbytes.aspx)
@@ -100,7 +100,7 @@ public char GetChar(int ordinal)
 		public long GetChars(int ordinal, long dataOffset, char[] buffer, int bufferOffset, int length)
 		{
 			var value = GetString(ordinal);
-			if (buffer == null)
+			if (buffer is null)
 				return value.Length;
 
 			CheckBufferArguments(dataOffset, buffer, bufferOffset, length);

src/MySqlConnector/Core/ServerSession.cs

@@ -131,7 +131,7 @@ public void AbortCancel(MySqlCommand command)
 
 		public void AddPreparedStatement(string commandText, PreparedStatements preparedStatements)
 		{
-			if (m_preparedStatements == null)
+			if (m_preparedStatements is null)
 				m_preparedStatements = new Dictionary<string, PreparedStatements>();
 			m_preparedStatements.Add(commandText, preparedStatements);
 		}
@@ -284,7 +284,7 @@ public async Task ConnectAsync(ConnectionSettings cs, ILoadBalancer loadBalancer
 						throw new MySqlException((int) MySqlErrorCode.UnableToConnectToHost, null, "Unable to connect to any of the specified MySQL hosts.");
 					}
 
-					var byteHandler = m_socket != null ? (IByteHandler) new SocketByteHandler(m_socket) : new StreamByteHandler(m_stream);
+					var byteHandler = m_socket is null ? new StreamByteHandler(m_stream) : (IByteHandler) new SocketByteHandler(m_socket);
 					m_payloadHandler = new StandardPayloadHandler(byteHandler);
 
 					payload = await ReceiveAsync(ioBehavior, cancellationToken).ConfigureAwait(false);
@@ -352,7 +352,7 @@ public async Task ConnectAsync(ConnectionSettings cs, ILoadBalancer loadBalancer
 					}
 				} while (shouldRetrySsl);
 
-				if (m_supportsConnectionAttributes && cs.ConnectionAttributes == null)
+				if (m_supportsConnectionAttributes && cs.ConnectionAttributes is null)
 					cs.ConnectionAttributes = CreateConnectionAttributes(cs.ApplicationName);
 
 				using (var handshakeResponsePayload = HandshakeResponse41Payload.Create(initialHandshake, cs, m_useCompression, m_characterSet, m_supportsConnectionAttributes ? cs.ConnectionAttributes : null))
@@ -394,7 +394,7 @@ public async Task<bool> TryResetConnectionAsync(ConnectionSettings cs, IOBehavio
 				// clear all prepared statements; resetting the connection will clear them on the server
 				ClearPreparedStatements();
 
-				if (DatabaseOverride == null && (ServerVersion.Version.CompareTo(ServerVersions.SupportsResetConnection) >= 0 || ServerVersion.MariaDbVersion?.CompareTo(ServerVersions.MariaDbSupportsResetConnection) >= 0))
+				if (DatabaseOverride is null && (ServerVersion.Version.CompareTo(ServerVersions.SupportsResetConnection) >= 0 || ServerVersion.MariaDbVersion?.CompareTo(ServerVersions.MariaDbSupportsResetConnection) >= 0))
 				{
 					m_logArguments[1] = ServerVersion.OriginalString;
 					Log.Debug("Session{0} ServerVersion={1} supports reset connection; sending reset connection request", m_logArguments);
@@ -410,7 +410,7 @@ public async Task<bool> TryResetConnectionAsync(ConnectionSettings cs, IOBehavio
 				else
 				{
 					// optimistically hash the password with the challenge from the initial handshake (supported by MariaDB; doesn't appear to be supported by MySQL)
-					if (DatabaseOverride == null)
+					if (DatabaseOverride is null)
 					{
 						m_logArguments[1] = ServerVersion.OriginalString;
 						Log.Debug("Session{0} ServerVersion={1} doesn't support reset connection; sending change user request", m_logArguments);
@@ -918,7 +918,7 @@ private async Task InitSslAsync(ProtocolCapabilities serverCapabilities, Connect
 					var store = new X509Store(StoreName.My, storeLocation);
 					store.Open(OpenFlags.ReadOnly | OpenFlags.OpenExistingOnly);
 
-					if (cs.CertificateThumbprint == null)
+					if (cs.CertificateThumbprint is null)
 					{
 						if (store.Certificates.Count == 0)
 						{
@@ -1064,11 +1064,8 @@ bool ValidateRemoteCertificate(object rcbSender, X509Certificate rcbCertificate,
 				return rcbPolicyErrors == SslPolicyErrors.None;
 			}
 
-			SslStream sslStream;
-			if (clientCertificates == null)
-				sslStream = new SslStream(m_stream, false, ValidateRemoteCertificate);
-			else
-				sslStream = new SslStream(m_stream, false, ValidateRemoteCertificate, ValidateLocalCertificate);
+			var sslStream = clientCertificates is null ? new SslStream(m_stream, false, ValidateRemoteCertificate) :
+				new SslStream(m_stream, false, ValidateRemoteCertificate, ValidateLocalCertificate);
 
 			var checkCertificateRevocation = cs.SslMode == MySqlSslMode.VerifyFull;