MessageBuilderTest.cs

using Raven.UnitTest.Support;
using System;
using System.Linq;
using Xunit;

namespace Raven.UnitTest
{
    public class MessageBuilderTest
    {
        private readonly MessageBuilder sut;
        private readonly byte[] message;

        public MessageBuilderTest()
        {
            sut = new MessageBuilder();
            message = new MessageSerializer().Serialize("Serialize Me!");
        }

        [Fact]
        public void Append_WholeMessage_RaisesEvent()
        {
            // Exercise
            Action exercise = () => sut.Append(message, message.Length);
            
            // Verify
            EventMonitor.AssertRaised(exercise, handler => sut.MessageReceived += handler);
        }

        [Fact]
        public void Append_HeaderThenBody_RaisesEvent()
        {
            // Setup
            const int HeaderSize = 4;
            byte[] header = message.Take(HeaderSize).ToArray();
            byte[] body = message.Skip(HeaderSize).ToArray();

            // Exercise
            Action exercise = () =>
            {
                sut.Append(header, header.Length);
                sut.Append(body, body.Length);
            };

            // Verify
            EventMonitor.AssertRaised(exercise, handler => sut.MessageReceived += handler);
        }

        [Fact]
        public void Append_PartialHeaderThenRest_RaisesEvent()
        {
            // Setup
            const int PartialHeaderSize = 2;
            byte[] partialHeader = message.Take(PartialHeaderSize).ToArray();
            byte[] rest = message.Skip(PartialHeaderSize).ToArray();

            // Exercise
            Action exercise = () =>
            {
                sut.Append(partialHeader, partialHeader.Length);
                sut.Append(rest, rest.Length);
            };

            // Verify
            EventMonitor.AssertRaised(exercise, handler => sut.MessageReceived += handler);
        }

        [Fact]
        public void Append_FragmentedMessage_RaisesEvent()
        {
            // Setup
            byte[] partialHeader = message.Take(2).ToArray();
            byte[] partialBody = message.Skip(2).Take(2).ToArray();
            byte[] rest = message.Skip(4).ToArray();

            // Exercise
            Action exercise = () =>
            {
                sut.Append(partialHeader, partialHeader.Length);
                sut.Append(partialBody, partialBody.Length);
                sut.Append(rest, rest.Length);
            };
            
            // Verify
            EventMonitor.AssertRaised(exercise, handler => sut.MessageReceived += handler);
        }

        [Fact]
        public void Append_TwoWholeMessages_RaisesEventTwice()
        {
            // Exercise
            Action exercise = () => sut.Append(message, message.Length);
            Action exercise1 = () => sut.Append(message, message.Length);

            // Verify
            EventMonitor.AssertRaised(exercise, handler => sut.MessageReceived += handler);
            EventMonitor.AssertRaised(exercise1, handler => sut.MessageReceived += handler);
        }
    }
}