NHibernate UserTypes Unit Testing

Question

Does anyone have a good approach to testing their UserTypes module?

As an example, I have an object in my model called DateRange that has a DatePoint start and a DatePoint end. In addition to performing range-type operations for two DateTimes, these objects allow me to adjust the accuracy for the task (i.e. Day, hour, minute, etc.). When storing in db for the application I'm working on, I just need to save the beginning and end as a DateTime, null is not allowed. I can't figure out how to map this without UserType, so I have:

/// <summary>User type to deal with <see cref="DateRange"/> persistence for time sheet tracking.</summary> public class TimePeriodType : IUserType { public SqlType[] SqlTypes { get { var types = new SqlType[2]; types[0] = new SqlType(DbType.DateTime); types[1] = new SqlType(DbType.DateTime); return types; } } public Type ReturnedType { get { return typeof(DateRange); } } /// <summary>Just return <see cref="DateRange.Equals(object)"/></summary> public new bool Equals(object x, object y) { return x != null && x.Equals(y); } /// <summary>Just return <see cref="DateRange.GetHashCode"/></summary> public int GetHashCode(object x) { return x.GetHashCode(); } public object NullSafeGet(IDataReader rs, string[] names, object owner) { var start = (DateTime)NHibernateUtil.DateTime.NullSafeGet(rs, names[0]); var end = (DateTime)NHibernateUtil.DateTime.NullSafeGet(rs, names[1]); return new DateRange(start, end, TimeSlice.Minute); } public void NullSafeSet(IDbCommand cmd, object value, int index) { Check.RequireNotNull<DateRange>(value); Check.RequireArgType<DateRange>(value); var dateRange = ((DateRange)value); NHibernateUtil.DateTime.NullSafeSet(cmd, dateRange.Start, index); NHibernateUtil.DateTime.NullSafeSet(cmd, dateRange.End, index); } public object DeepCopy(object value) { Check.RequireNotNull<DateRange>(value); Check.RequireArgType<DateRange>(value); var dateRange = ((DateRange) value); return new DateRange(dateRange.Start, dateRange.End); } public bool IsMutable { get { return false; } } public object Replace(object original, object target, object owner) { //because it is immutable so we can just return it as is return original; } public object Assemble(object cached, object owner) { //Used for caching, as it is immutable we can just return it as is return cached; } public object Disassemble(object value) { //Used for caching, as it is immutable we can just return it as is return value; } } 

}

Now I am looking for a way to prove that this works. Thanks in advance!

Cheers, Berryl

Answer 1

I created a custom type for System.Drawing.Color, and this is how I tested it with MSTest and Moq .

ColorUserType.cs:

  public class ColorUserType: IUserType
 {
     public object Assemble (object cached, object owner)
     {
         return cached;
     }

     public object DeepCopy (object value)
     {
         return value;
     }

     public object Disassemble (object value)
     {
         return value;
     }

     public new bool Equals (object x, object y)
     {
         if (ReferenceEquals (x, y))
         {
             return true;
         }
         if (x == null || y == null)
         {
             return false;
         }
         return x.Equals (y);
     }

     public int GetHashCode (object x)
     {
         return x == null?  typeof (Color) .GetHashCode () + 473: x.GetHashCode ();
     }

     public bool IsMutable
     {
         get 
         {
             return true;
         }
     }

     public object NullSafeGet (IDataReader rs, string [] names, object owner)
     {
         var obj = NHibernateUtil.String.NullSafeGet (rs, names [0]);
         if (obj == null)
         {
             return null;
         }
         return ColorTranslator.FromHtml ((string) obj);
     }

     public void NullSafeSet (IDbCommand cmd, object value, int index)
     {
         if (value == null)
         {
             ((IDataParameter) cmd.Parameters [index]) .Value = DBNull.Value;
         }
         else
         {
             ((IDataParameter) cmd.Parameters [index]) .Value = ColorTranslator.ToHtml ((Color) value);
         }
     }

     public object Replace (object original, object target, object owner)
     {
         return original;
     }

     public Type ReturnedType
     {
         get
         {
             return typeof (Color);
         }
     }

     public SqlType [] SqlTypes
     {
         get
         {
             return new [] {new SqlType (DbType.StringFixedLength)};
         }
     }
 }

ColorUserTypeTests.cs

  [TestClass]
     public class ColorUserTypeTests
     {
         public TestContext TestContext {get;  set;  }

         [TestMethod]
         public void AssembleTest ()
         {
             var color = Color.Azure;
             var userType = new ColorUserType ();
             var val = userType.Assemble (color, null);
             Assert.AreEqual (color, val);
         }

         [TestMethod]
         public void DeepCopyTest ()
         {
             var color = Color.Azure;
             var userType = new ColorUserType ();
             var val = userType.DeepCopy (color);
             Assert.AreEqual (color, val);
         }

         [TestMethod]
         public void DissasembleTest ()
         {
             var color = Color.Azure;
             var userType = new ColorUserType ();
             var val = userType.Disassemble (color);
             Assert.AreEqual (color, val);
         }

         [TestMethod]
         public void EqualsTest ()
         {
             var color1 = Color.Azure;
             var color2 = Color.Bisque;
             var color3 = Color.Azure;
             var userType = new ColorUserType ();

             var obj1 = (object) color1;
             var obj2 = obj1;

             Assert.IsFalse (userType.Equals (color1, color2));
             Assert.IsTrue (userType.Equals (color1, color1));
             Assert.IsTrue (userType.Equals (color1, color3));
             Assert.IsFalse (userType.Equals (color1, null));
             Assert.IsFalse (userType.Equals (null, color1));
             Assert.IsTrue (userType.Equals (null, null));
             Assert.IsTrue (userType.Equals (obj1, obj2));
         }

         [TestMethod]
         public void GetHashCodeTest ()
         {
             var color = Color.Azure;
             var userType = new ColorUserType ();

             Assert.AreEqual (color.GetHashCode (), userType.GetHashCode (color));
             Assert.AreEqual (typeof (Color) .GetHashCode () + 473, userType.GetHashCode (null));
         }

         [TestMethod]
         public void IsMutableTest ()
         {
             var userType = new ColorUserType ();
             Assert.IsTrue (userType.IsMutable);
         }

         [TestMethod]
         public void NullSafeGetTest ()
         {
             var dataReaderMock = new Mock ();
             dataReaderMock.Setup (m => m.GetOrdinal ("white")) .Returns (0);
             dataReaderMock.Setup (m => m.IsDBNull (0)) .Returns (false);
             dataReaderMock.Setup (m => m [0]) .Returns ("#ffffff");

             var userType = new ColorUserType ();
             var val = (Color) userType.NullSafeGet (dataReaderMock.Object, new [] {"white"}, null);

             Assert.AreEqual ("ffffffff", val.Name, "The wrong color was returned.");

             dataReaderMock.Setup (m => m.IsDBNull (It.IsAny ())) .Returns (true);
             Assert.IsNull (userType.NullSafeGet (dataReaderMock.Object, new [] {"black"}, null), "The color was not null.");

             dataReaderMock.VerifyAll ();
         }

         [TestMethod]
         public void NullSafeSetTest ()
         {
             const string color = "#ffffff";
             const int index = 0;

             var mockFactory = new MockFactory (MockBehavior.Default);

             var parameterMock = mockFactory.Create ();
             parameterMock.SetupProperty (p => p.Value, string.Empty);

             var parameterCollectionMock = mockFactory.Create ();
             parameterCollectionMock.Setup (m => m [0]) .Returns (parameterMock.Object);

             var commandMock = mockFactory.Create ();
             commandMock.Setup (m => m.Parameters) .Returns (parameterCollectionMock.Object);

             var userType = new ColorUserType ();

             userType.NullSafeSet (commandMock.Object, ColorTranslator.FromHtml (color), index);
             Assert.AreEqual (0, string.Compare ((string) ((IDataParameter) commandMock.Object.Parameters [0]) .Value, color, true));

             userType.NullSafeSet (commandMock.Object, null, index);
             Assert.AreEqual (DBNull.Value, ((IDataParameter) commandMock.Object.Parameters [0]) .Value);

             mockFactory.VerifyAll ();
         }

         [TestMethod]
         public void ReplaceTest ()
         {
             var color = Color.Azure;
             var userType = new ColorUserType ();
             Assert.AreEqual (color, userType.Replace (color, null, null));
         }

         [TestMethod]
         public void ReturnedTypeTest ()
         {
             var userType = new ColorUserType ();
             Assert.AreEqual (typeof (Color), userType.ReturnedType);
         }

         [TestMethod]
         public void SqlTypesTest ()
         {
             var userType = new ColorUserType ();
             Assert.AreEqual (1, userType.SqlTypes.Length);
             Assert.AreEqual (new SqlType (DbType.StringFixedLength), userType.SqlTypes [0]);
         }
     }

Answer 2

I thought I could mock / fake some of the dependencies here, but came to the conclusion that the best way to do this is to use a database.

Some things I learned along the way:

1) it is worth the effort when you study NHibernate methods to have a special set of tools, including a way to quickly configure db and test fixture for it (the same flexible tools that you will need for everything else) and a special test lab in which you no emotional investment.

2) mocks are not susceptible to interfaces that you do not own, for example IDataReader.

Greetings