如何在C＃中针对其中的虚拟方法执行抽象类的Moq测试？

Question

I would like to perform testing for below abstract Streaming class which has two virtual methods that are overridden in the Asset class in same project. Here the SerializeBinary() method converts an object into binary streams and DeserializeFromBinary() method does the opposite of SerializeBinary() .

How to write test class for comparing both using Moq?

I go through from here:

This is part of my code:

Streaming class:

public abstract class Streaming
{
        private static int _streamingIDExponent = 41;
        public const string MonthLookup = "ABCDEFGHIJK";
        public const string ExpiryStringFormat = "ddMMMyyyy";
        public const double DefaultTicksPerPoint = 3;
        private long _StreamingID;
        private int _minQty = DefaultMinimumQty;

        public virtual void SerializeBinary(BinaryStreamWriter binaryStreamWriter)
        {
                 binaryStreamWriter.Write(_StreamingID);
                 binaryStreamWriter.Write(_ex_StreamingID);
                 binaryStreamWriter.Write(_minQty);
                 binaryStreamWriter.Write(_extendedProperties.Count);

                 foreach (KeyValuePair<StreamingPropertyName, StreamingProperty> dictionaryEntry in _extendedProperties)
                 {
                     dictionaryEntry.Value.SerializeBinary(binaryStreamWriter);
                 }
}

public virtual bool DeserializeFromBinary(BinaryStreamReader binaryStreamReader, out string errorString)
{
         errorString = string.Empty;

         try
         {
               _StreamingID = binaryStreamReader.ReadInt64();
               _exStreamingID = binaryStreamReader.ReadInt64();
               _minQty = binaryStreamReader.ReadInt32();    
         }
         catch (Exception oEx)
         {
               errorString = oEx.Message;
         }

         return string.IsNullOrEmpty(errorString);
}

Asset class:

public class Asset : Streaming
{
    public override void SerializeBinary(BinaryStreamWriter binaryStreamWriter)
    {
        base.SerializeBinary(binaryStreamWriter);
    }

    public override bool DeserializeFromBinary(BinaryStreamReader binaryStreamReader, out string errorString)
    {
            if (!base.DeserializeFromBinary(binaryStreamReader, out errorString))
                   return false;

            try
            {
                  return true;
            }
            catch (Exception oEx)
            {
                 errorString = oEx.Message;
                 return false;
            }
     }
 }

Answer 1

you can create a new Mock of your Streaming class like this:

var streamingMock = new Mock<Streaming> { CallBase = true };

The call base is important because it will then execute the implemented code in your concrete class. Then you can call the methods via the Object property:

streamingMock.Object.SerializeBinary(...);

Hope this helps

Answer 2

There's no good way to test the interaction between Asset and Streaming with Moq in your current implementation. However, if you're willing to change the implementation of the classes just a bit, you can get it done. Basically, you'll want to move the logic of the Streaming class's methods into new methods, and you can then mock those.

public abstract class Streaming
{
    public virtual void SerializeBinaryCore(BinaryStreamWriter writer)
    {
        // put the logic from your original SerializeBinary method here...
    }

    public virtual bool DeserializeFromBinaryCore(BinaryStreamReader reader, out string errorMessage)
    {
        // put the logic from your original DeserializeFromBinary method here...
    }

    public abstract void SerializeBinary(BinaryStreamWriter writer);

    public abstract bool DeserializeFromBinary(BinaryStreamReader reader, out string errorMessage);
}

And then tweak your Asset class as follows:

public class Asset : Streaming
{
    public override void SerializeBinary(BinaryStreamWriter writer)
    {
        SerializeBinaryCore(writer);
    }
    public override void DeserializeFromBinary(BinaryStreamReader reader, out string errorMessage)
    {
        var result = DeserializeFromBinaryCore(reader, out errorMessage);
        // put the rest of your Asset deserialization logic here...
    }
}

In your test, you need to create a Mock<Asset> { CallBase = true } , and then create setups for the SerializeBinaryCore and DeserializeFromBinaryCore methods.