From 96748a7a596750ad4afabb85479768142bcc99cf Mon Sep 17 00:00:00 2001
From: "DESKTOP-KRJIM7J\\Roman"
 <23335944+rrrooommmaaa@users.noreply.github.com>
Date: Sat, 11 May 2024 16:00:43 +0200
Subject: [PATCH] #3251 coerce output in RuleContext.AddOutValue

---
 .../ValidationRules/OutputCoercionTest.cs     | 69 +++++++++++++++++++
 Source/Csla/Rules/RuleContext.cs              |  2 +-
 2 files changed, 70 insertions(+), 1 deletion(-)
 create mode 100644 Source/Csla.test/ValidationRules/OutputCoercionTest.cs

diff --git a/Source/Csla.test/ValidationRules/OutputCoercionTest.cs b/Source/Csla.test/ValidationRules/OutputCoercionTest.cs
new file mode 100644
index 0000000000..98e5885f9a
--- /dev/null
+++ b/Source/Csla.test/ValidationRules/OutputCoercionTest.cs
@@ -0,0 +1,69 @@
+using Csla.Rules;
+using Csla.TestHelpers;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+namespace Csla.Test.ValidationRules
+{
+  public class CalculationObject : BusinessBase<CalculationObject>
+  {
+    public static readonly PropertyInfo<int> PropertyAProperty = RegisterProperty<int>(nameof(PropertyA));
+    public int PropertyA
+    {
+      get { return GetProperty(PropertyAProperty); }
+      set { SetProperty(PropertyAProperty, value); }
+    }
+
+    public static readonly PropertyInfo<int> PropertyBProperty = RegisterProperty<int>(nameof(PropertyB));
+    public int PropertyB
+    {
+      get { return GetProperty(PropertyBProperty); }
+      set { SetProperty(PropertyBProperty, value); }
+    }
+
+    public static readonly PropertyInfo<string> SumPropertyProperty = RegisterProperty<string>(nameof(SumProperty));
+    public string SumProperty
+    {
+      get { return GetProperty(SumPropertyProperty); }
+      private set { LoadProperty(SumPropertyProperty, value); }
+    }
+
+    protected override void AddBusinessRules()
+    {
+      base.AddBusinessRules();
+
+      // Register the sum properties rule
+      BusinessRules.AddRule(new CalcSumRule(SumPropertyProperty, PropertyAProperty, PropertyBProperty));
+    }
+
+    [Create]
+    private void Create()
+    {
+      BusinessRules.CheckRules();
+    }
+  }
+
+  [TestClass]
+  public class CoerceTests
+  {
+    private static TestDIContext _testDIContext;
+
+    [ClassInitialize]
+    public static void ClassInitialize(TestContext testContext)
+    {
+      _testDIContext = TestDIContextFactory.CreateDefaultContext();
+    }
+
+    [TestMethod]
+    public void CalcSumRole_SavesToStringProperty()
+    {
+      // Create an instance of a DataPortal that can be used for instantiating objects
+      var dataPortal = _testDIContext.CreateDataPortal<CalculationObject>();
+      var obj = dataPortal.Create();
+
+      obj.PropertyA = 10;
+      obj.PropertyB = 20;
+
+      Assert.AreEqual("30", obj.SumProperty, "string SumProperty should reflect the sum of PropertyA and PropertyB.");
+    }
+  }
+}
diff --git a/Source/Csla/Rules/RuleContext.cs b/Source/Csla/Rules/RuleContext.cs
index ae040da6bc..fed49983dd 100644
--- a/Source/Csla/Rules/RuleContext.cs
+++ b/Source/Csla/Rules/RuleContext.cs
@@ -408,7 +408,7 @@ public void AddOutValue(object value)
     /// <exception cref="System.ArgumentOutOfRangeException">When property is not defined in AffectedProperties list.</exception>   
     public void AddOutValue(Csla.Core.IPropertyInfo property, object value)
     {
-      _outputPropertyValues.Value[property] = value;
+      _outputPropertyValues.Value[property] = (value is null) ? property.DefaultValue : Csla.Utilities.CoerceValue(property.Type, value.GetType(), null, value);
     }