migrate BookSleeve "Scripting" suite; fix "eval inside transaction" bug

MigratedBookSleeveTestSuite/Program.cs

@@ -188,11 +188,11 @@ where Attribute.IsDefined(method, typeof(TestAttribute))
             }
             Console.WriteLine("Passed: {0}; Failed: {1}", pass, fail);
             foreach (var msg in epicFail) Console.WriteLine(msg);
-#if DEBUG
-            Console.WriteLine();
-            Console.WriteLine("Callbacks: {0:###,###,##0} sync, {1:###,###,##0} async",
-                BookSleeve.RedisConnectionBase.AllSyncCallbacks, BookSleeve.RedisConnectionBase.AllAsyncCallbacks);
-#endif
+//#if DEBUG
+//            Console.WriteLine();
+//            Console.WriteLine("Callbacks: {0:###,###,##0} sync, {1:###,###,##0} async",
+//                BookSleeve.RedisConnectionBase.AllSyncCallbacks, BookSleeve.RedisConnectionBase.AllAsyncCallbacks);
+//#endif
 
         }
     }

StackExchange.Redis/StackExchange/Redis/PhysicalConnection.cs

@@ -273,9 +273,18 @@ internal Message GetSelectDatabaseCommand(int targetDatabase, Message message)
                     }
                     return null;
                 }
+
+                if(message.Command == RedisCommand.SELECT)
+                {
+                    // this could come from an EVAL/EVALSHA inside a transaction, for example; we'll accept it
+                    bridge.Trace("Switching database: " + targetDatabase);
+                    currentDatabase = targetDatabase;
+                    return null;
+                }
+
                 if (TransactionActive)
                 {// should never see this, since the API doesn't allow it; thus not too worried about ExceptionFactory
-                    throw new RedisCommandException("Multiple databases inside a transaction are not currently supported" + targetDatabase);
+                    throw new RedisCommandException("Multiple databases inside a transaction are not currently supported: " + targetDatabase);
                 }
 
                 if (available != 0 && targetDatabase >= available) // we positively know it is out of range
@@ -284,12 +293,16 @@ internal Message GetSelectDatabaseCommand(int targetDatabase, Message message)
                 }
                 bridge.Trace("Switching database: " + targetDatabase);
                 currentDatabase = targetDatabase;
+                return GetSelectDatabaseCommand(targetDatabase);
+            }
+            return null;
+        }
+        internal static Message GetSelectDatabaseCommand(int targetDatabase)
+        {
             return targetDatabase < DefaultRedisDatabaseCount
                     ? ReusableChangeDatabaseCommands[targetDatabase] // 0-15 by default
                         : Message.Create(targetDatabase, CommandFlags.FireAndForget, RedisCommand.SELECT);
         }
-            return null;
-        }
 
         internal int GetSentAwaitingResponseCount()
         {

StackExchange.Redis/StackExchange/Redis/RedisResult.cs

@@ -7,6 +7,7 @@ namespace StackExchange.Redis
     /// </summary>
     public abstract class RedisResult
     {
+
         // internally, this is very similar to RawResult, except it is designed to be usable
         // outside of the IO-processing pipeline: the buffers are standalone, etc
 
@@ -42,6 +43,11 @@ internal static RedisResult TryCreate(PhysicalConnection connection, RawResult r
             }
         }
 
+        /// <summary>
+        /// Indicates whether this result was a null result
+        /// </summary>
+        public abstract bool IsNull { get; }
+
         /// <summary>
         /// Interprets the result as a String
         /// </summary>
@@ -168,6 +174,10 @@ internal static RedisResult TryCreate(PhysicalConnection connection, RawResult r
         internal abstract string[] AsStringArray();
         private sealed class ArrayRedisResult : RedisResult
         {
+            public override bool IsNull
+            {
+                get { return value == null; }
+            }
             private readonly RedisResult[] value;
             public ArrayRedisResult(RedisResult[] value)
             {
@@ -275,6 +285,10 @@ public ErrorRedisResult(string value)
                 if (value == null) throw new ArgumentNullException("value");
                 this.value = value;
             }
+            public override bool IsNull
+            {
+                get { return value == null; }
+            }
             public override string ToString() { return value; }
             internal override bool AsBoolean() { throw new RedisServerException(value); }
 
@@ -326,6 +340,11 @@ public SingleRedisResult(RedisValue value)
                 this.value = value;
             }
 
+            public override bool IsNull
+            {
+                get { return value.IsNull; }
+            }
+
             public override string ToString() { return value.ToString(); }
             internal override bool AsBoolean() { return (bool)value; }
 

StackExchange.Redis/StackExchange/Redis/RedisTransaction.cs

@@ -86,6 +86,22 @@ internal override Task<T> ExecuteAsync<T>(Message message, ResultProcessor<T> pr
             // store it, and return the task of the *outer* command
             // (there is no task for the inner command)
             (pending ?? (pending = new List<QueuedMessage>())).Add(queued);
+
+
+            switch(message.Command)
+            {
+                case RedisCommand.EVAL:
+                case RedisCommand.EVALSHA:
+                    // people can do very naughty things in an EVAL
+                    // including change the DB; change it back to what we
+                    // think it should be!
+                    var sel = PhysicalConnection.GetSelectDatabaseCommand(message.Db);
+                    queued = new QueuedMessage(sel);
+                    wasQueued = ResultBox<bool>.Get(null);
+                    queued.SetSource(wasQueued, QueuedProcessor.Default);
+                    pending.Add(queued);
+                    break;
+            }
             return task;
         }