Added an ImapToken cache to try and reduce ImapToken allocations

Author: jstedfast

MailKit/ByteArrayBuilder.cs

@@ -45,6 +45,15 @@ public int Length {
 			get { return length; }
 		}
 
+		public byte this[int index] {
+			get { return buffer[index]; }
+		}
+
+		public byte[] GetBuffer ()
+		{
+			return buffer;
+		}
+
 		void EnsureCapacity (int capacity)
 		{
 			if (capacity > buffer.Length) {

MailKit/MailKit.csproj

@@ -64,6 +64,7 @@
 
   <ItemGroup>
     <Compile Include="Net\Imap\AsyncImapClient.cs" />
+    <Compile Include="Net\Imap\HashCode.cs" Condition=" $(TargetFramework.StartsWith('net4')) Or '$(TargetFramework)' == 'netstandard2.0' " />
     <Compile Include="Net\Imap\IImapClient.cs" />
     <Compile Include="Net\Imap\IImapFolder.cs" />
     <Compile Include="Net\Imap\ImapAuthenticationSecretDetector.cs" />
@@ -88,6 +89,7 @@
     <Compile Include="Net\Imap\ImapSearchQueryOptimizer.cs" />
     <Compile Include="Net\Imap\ImapStream.cs" />
     <Compile Include="Net\Imap\ImapToken.cs" />
+    <Compile Include="Net\Imap\ImapTokenCache.cs" />
     <Compile Include="Net\Imap\ImapUtils.cs" />
     <Compile Include="Net\Pop3\AsyncPop3Client.cs" />
     <Compile Include="Net\Pop3\IPop3Client.cs" />

MailKit/MailKitLite.csproj

@@ -69,6 +69,7 @@
 
   <ItemGroup>
     <Compile Include="Net\Imap\AsyncImapClient.cs" />
+    <Compile Include="Net\Imap\HashCode.cs" Condition=" $(TargetFramework.StartsWith('net4')) Or '$(TargetFramework)' == 'netstandard2.0' " />
     <Compile Include="Net\Imap\IImapClient.cs" />
     <Compile Include="Net\Imap\IImapFolder.cs" />
     <Compile Include="Net\Imap\ImapAuthenticationSecretDetector.cs" />
@@ -93,6 +94,7 @@
     <Compile Include="Net\Imap\ImapSearchQueryOptimizer.cs" />
     <Compile Include="Net\Imap\ImapStream.cs" />
     <Compile Include="Net\Imap\ImapToken.cs" />
+    <Compile Include="Net\Imap\ImapTokenCache.cs" />
     <Compile Include="Net\Imap\ImapUtils.cs" />
     <Compile Include="Net\Pop3\AsyncPop3Client.cs" />
     <Compile Include="Net\Pop3\IPop3Client.cs" />