title: NSubstitute Checking received calls don't work
body: <p>Hey guys im new with the NSubstitute framework. I'm trying to test some of my classes, but when i use NSubstitute to check received calls it says received no matching calls. </p>
  
  <p>I'm trying to test if the method Tick() is receiving update() from track class. </p>
  
  <pre><code>using System;
  using System.Collections.Generic;
  using System.Linq;
  using System.Text;
  using System.Threading.Tasks;
  using ATM_System.Event;
  using ATM_System.EventDetection;
  using ATM_System.Region;
  using ATM_System.Track;
  
  namespace ATM_System
   {
  public class ATM
  {
      private List&lt;ITrack&gt; _tracks;
      private IRegion _region;
      private List&lt;IEventDetection&gt; _eventdetects;
      private List&lt;IEvent&gt; _events;
  
      public ATM()
      {
          _tracks = new List&lt;ITrack&gt;();
          _region = new Region.Region(100000,100000); //could be changed by user
          _events = new List&lt;IEvent&gt;();
          _eventdetects = new List&lt;IEventDetection&gt;();
  
  
      }
  
  
  
      public void Tick()
      {            
  
          // update track positions
          foreach (var track1 in _tracks)
          {
              track1.update();
          }
  
          //check for events
          foreach (var detector in _eventdetects)
          {
              _events.AddRange(detector.DetectEvent(_tracks));
          }
  
          //handle events and output
          foreach (var event1 in _events)
          {
              event1.HandleEvent();
              event1.LogEvent();
          }
  
      }
  
      public void IncomingTrack(ITrack track)
      {
          //add incoming track
          _tracks.Add(track);
      }
  }
  }
  </code></pre>
  
  <p>TEST FILE</p>
  
  <pre><code>using System;
  using System.Collections.Generic;
  using System.Linq;
  using System.Text;
  using System.Threading.Tasks;
  using ATM_System.Event;
  using ATM_System.EventDetection;
  using ATM_System.Track;
  using NUnit.Framework;
  using NSubstitute;
  
  namespace ATM_System.Tests.Unit
  {
  [TestFixture]
  class ATMUnitTests
  {
  
      private ATM _uut;
      private ITrack _track;
      private IEvent _event;
      private IEventDetection _eventDetection;
  
      [SetUp]
      public void Setup()
      {
          _track = Substitute.For&lt;ITrack&gt;();
          _event = Substitute.For&lt;IEvent&gt;();
          _eventDetection = Substitute.For&lt;IEventDetection&gt;();
  
          _uut = new ATM();
      }
  
      [Test]
      public void Tick_UpdateTracks_TracksUpdated()
      {
          _uut.Tick();
          _track.Received().update();
      }
  
  }
  }
  </code></pre>