using System;

namespace NUnit.Framework
{
	/// <summary>
	/// Asserter that verifies two objects are different.
	/// </summary>
	public class NotSameAsserter : ComparisonAsserter
	{
		/// <summary>
		/// Construct a NotSameAsserter object
		/// </summary>
		/// <param name="expected">The expected value</param>
		/// <param name="actual">The actual value</param>
		/// <param name="message">A user-defined message for use in reporting errors</param>
		/// <param name="args">Arguments to be used in formatting the user-defined message</param>
		public NotSameAsserter( object expected, object actual, string message, params object[] args)
			: base( expected, actual, message, args ) { }

		/// <summary>
		/// Tests that the objects are not the same
		/// </summary>
		public override bool Test()
		{
#if NETCF && FX1_1 //andyh
            return !SameAsserter.object_ReferenceEquals( expected, actual );
            //throw new NotSupportedException("Assert.NotSame (ReferenceEquals) not supported on CFv1.");
#else
			return !object.ReferenceEquals( expected, actual );
#endif
		}

		/// <summary>
		/// Provides a message in case of failure
		/// </summary>
		public override string Message
		{
			get
			{
				FailureMessage.AddLine( "Objects should be different" );
				FailureMessage.AddLine( "\tboth are: {0}", AssertionFailureMessage.FormatObjectForDisplay( this.actual ) );
				return FailureMessage.ToString();
			}
		}
	}
}