Add more decider tests

test/Fraktalio.FModel.Tests/DeciderExtensions.cs

@@ -11,7 +11,7 @@ public static IEnumerable<E> GivenEvents<C, S, E>(this IDecider<C, S, E> decider
         return decider.Decide(command(), currentState);
     }
 
-    public static S GivenState<C, S, E>(this IDecider<C, S, E> decider, S state, Func<C> command)
+    public static S GivenState<C, S, E>(this IDecider<C, S, E> decider, S? state, Func<C> command)
     {
         var currentState = state != null ? state : decider.InitialState;
         var events = decider.Decide(command(), currentState);

test/Fraktalio.FModel.Tests/EnumerableExtensions.cs

@@ -10,7 +10,7 @@ public static void ExpectActions<A>(this IEnumerable<A> flow, params A[] expecte
         list.Should().BeEquivalentTo(expected);
     }
 
-    public static void ThenEvents<E>(this IEnumerable<E> flow, IEnumerable<E> expected)
+    public static void ThenEvents<E>(this IEnumerable<E> flow, params E[] expected)
     {
         var list = flow.ToList();
         list.Should().BeEquivalentTo(expected);

test/Fraktalio.FModel.Tests/DeciderTest.cs → test/Fraktalio.FModel.Tests/EventSourcedDeciderTest.cs

@@ -10,43 +10,43 @@
 namespace Fraktalio.FModel.Tests;
 
 [Category("unit")]
-public class DeciderTest
+public class EventSourcedDeciderTest
 {
-    private EvenNumberDecider _evenNumberDecider;
-    private OddNumberDecider _oddNumberDecider;
-
-    [SetUp]
-    public void Setup()
-    {
-        _evenNumberDecider = new EvenNumberDecider();
-        _oddNumberDecider = new OddNumberDecider();
-    }
+    private readonly EvenNumberDecider _evenNumberDecider = new();
+    private readonly OddNumberDecider _oddNumberDecider = new();
 
     [Test]
     public void GivenEmptyEvents_AddEvenNumber() =>
         _evenNumberDecider
             .GivenEvents([],
                 () => new EvenNumberCommand.AddEvenNumber(Description.Create("2"), Number.Create(2)))
-            .ThenEvents(new[] { new EvenNumberAdded(Description.Create("2"), Number.Create(2)) });
+            .ThenEvents([new EvenNumberAdded(Description.Create("2"), Number.Create(2))]);
 
     [Test]
-    public void GivenPreviousState_AddEvenNumber() =>
+    public void GivenEvents_AddEvenNumber() =>
         _evenNumberDecider
             .GivenEvents(new[] { new EvenNumberAdded(Description.Create("2"), Number.Create(2)) },
                 () => new EvenNumberCommand.AddEvenNumber(Description.Create("4"), Number.Create(4)))
-            .ThenEvents(new[] { new EvenNumberAdded(Description.Create("4"), Number.Create(6)) });
+            .ThenEvents([new EvenNumberAdded(Description.Create("4"), Number.Create(6))]);
 
     [Test]
-    public void GivenPreviousState_SubtractEvenNumber() =>
+    public void GivenEvents_SubtractEvenNumber() =>
         _evenNumberDecider
             .GivenEvents(new EvenNumberAdded[] { new(Description.Create("8"), Number.Create(8)) },
                 () => new EvenNumberCommand.SubtractEvenNumber(Description.Create("2"), Number.Create(2)))
-            .ThenEvents(new EvenNumberSubtracted[] { new(Description.Create("2"), Number.Create(6)) });
+            .ThenEvents([new EvenNumberSubtracted(Description.Create("2"), Number.Create(6))]);
 
     [Test]
-    public void GivenPreviousState_AddOddNumber() =>
+    public void GivenEvents_AddOddNumber() =>
         _oddNumberDecider
             .GivenEvents(new OddNumberAdded[] { new(Description.Create("3"), Number.Create(3)) },
                 () => new OddNumberCommand.AddOddNumber(Description.Create("1"), Number.Create(1)))
-            .ThenEvents(new OddNumberAdded[] { new(Description.Create("1"), Number.Create(4)) });
+            .ThenEvents([new OddNumberAdded(Description.Create("1"), Number.Create(4))]);
+
+    [Test]
+    public void GivenEvents_SubtractOddNumber() =>
+        _oddNumberDecider
+            .GivenEvents(new OddNumberAdded[] { new(Description.Create("3"), Number.Create(3)) },
+                () => new OddNumberCommand.SubtractOddNumber(Description.Create("1"), Number.Create(1)))
+            .ThenEvents([new OddNumberAdded(Description.Create("1"), Number.Create(2))]);
 }

test/Fraktalio.FModel.Tests/Examples/Numbers/Even/EvenNumberDecider.cs

@@ -1,4 +1,3 @@
-using Fraktalio.FModel.Tests.Examples.Numbers.States;
 using EvenNumberCommand = Fraktalio.FModel.Tests.Examples.Numbers.NumberCommand.EvenNumberCommand;
 using EvenNumberEvent = Fraktalio.FModel.Tests.Examples.Numbers.NumberEvent.EvenNumberEvent;
 

test/Fraktalio.FModel.Tests/Examples/Numbers/NumberState.cs

@@ -1,19 +1,7 @@
-namespace Fraktalio.FModel.Tests.Examples.Numbers.States;
+namespace Fraktalio.FModel.Tests.Examples.Numbers;
 
-public abstract class NumberState
-{
-    public abstract Description Description { get; }
-    public abstract Number Value { get; }
-}
+public abstract record NumberState(Description Description, Number Value);
 
-public sealed class EvenNumberState(Description description, Number value) : NumberState
-{
-    public override Description Description { get; } = description;
-    public override Number Value { get; } = value;
-}
+public sealed record EvenNumberState(Description Description, Number Value) : NumberState(Description, Value);
 
-public sealed class OddNumberState(Description description, Number value) : NumberState
-{
-    public override Description Description { get; } = description;
-    public override Number Value { get; } = value;
-}
+public sealed record OddNumberState(Description Description, Number Value) : NumberState(Description, Value);

test/Fraktalio.FModel.Tests/Examples/Numbers/Odd/OddNumberDecider.cs

@@ -1,4 +1,3 @@
-using Fraktalio.FModel.Tests.Examples.Numbers.States;
 using OddNumberCommand = Fraktalio.FModel.Tests.Examples.Numbers.NumberCommand.OddNumberCommand;
 using OddNumberEvent = Fraktalio.FModel.Tests.Examples.Numbers.NumberEvent.OddNumberEvent;
 

test/Fraktalio.FModel.Tests/StateStoredDeciderTest.cs

@@ -0,0 +1,49 @@
+using Fraktalio.FModel.Tests.Examples.Numbers;
+using Fraktalio.FModel.Tests.Examples.Numbers.Even;
+using Fraktalio.FModel.Tests.Examples.Numbers.Odd;
+using EvenNumberCommand = Fraktalio.FModel.Tests.Examples.Numbers.NumberCommand.EvenNumberCommand;
+using OddNumberCommand = Fraktalio.FModel.Tests.Examples.Numbers.NumberCommand.OddNumberCommand;
+
+namespace Fraktalio.FModel.Tests;
+
+[Category("unit")]
+public class StateStoredDeciderTest
+{
+    private readonly EvenNumberDecider _evenNumberDecider = new();
+    private readonly OddNumberDecider _oddNumberDecider = new();
+
+    [Test]
+    public void GivenEmptyState_AddEvenNumber() =>
+        _evenNumberDecider
+            .GivenState(null,
+                () => new EvenNumberCommand.AddEvenNumber(Description.Create("2"), Number.Create(2)))
+            .ThenState(new EvenNumberState(Description.Create("Initial state + 2"), Number.Create(2)));
+
+    [Test]
+    public void GivenState_AddEvenNumber() =>
+        _evenNumberDecider
+            .GivenState(new EvenNumberState(Description.Create("2"), Number.Create(2)),
+                () => new EvenNumberCommand.AddEvenNumber(Description.Create("4"), Number.Create(4)))
+            .ThenState(new EvenNumberState(Description.Create("2 + 4"), Number.Create(6)));
+
+    [Test]
+    public void GivenState_SubtractEvenNumber() =>
+        _evenNumberDecider
+            .GivenState(new EvenNumberState(Description.Create("8"), Number.Create(8)),
+                () => new EvenNumberCommand.SubtractEvenNumber(Description.Create("2"), Number.Create(2)))
+            .ThenState(new EvenNumberState(Description.Create("8 - 2"), Number.Create(6)));
+
+    [Test]
+    public void GivenState_AddOddNumber() =>
+        _oddNumberDecider
+            .GivenState(new OddNumberState(Description.Create("3"), Number.Create(3)),
+                () => new OddNumberCommand.AddOddNumber(Description.Create("1"), Number.Create(1)))
+            .ThenState(new OddNumberState(Description.Create("3 + 1"), Number.Create(4)));
+
+    [Test]
+    public void GivenState_SubtractOddNumber() =>
+        _oddNumberDecider
+            .GivenState(new OddNumberState(Description.Create("3"), Number.Create(3)),
+                () => new OddNumberCommand.SubtractOddNumber(Description.Create("1"), Number.Create(1)))
+            .ThenState(new OddNumberState(Description.Create("3 - 1"), Number.Create(2)));
+}