From 97b2cbfde4bd6a760793bd23b285e762b9a8071f Mon Sep 17 00:00:00 2001
From: Sipke Schoorstra <sipkeschoorstra@outlook.com>
Date: Wed, 4 Aug 2021 15:12:38 +0200
Subject: [PATCH] Improve type conversion error message

---
 .../Exceptions/TypeConversionException.cs     | 22 +++++++++++++++++++
 .../Extensions/ObjectConverter.cs             | 11 +++++++++-
 2 files changed, 32 insertions(+), 1 deletion(-)
 create mode 100644 src/core/Elsa.Abstractions/Exceptions/TypeConversionException.cs

diff --git a/src/core/Elsa.Abstractions/Exceptions/TypeConversionException.cs b/src/core/Elsa.Abstractions/Exceptions/TypeConversionException.cs
new file mode 100644
index 000000000..12f2edd31
--- /dev/null
+++ b/src/core/Elsa.Abstractions/Exceptions/TypeConversionException.cs
@@ -0,0 +1,22 @@
+using System;
+
+namespace Elsa.Exceptions
+{
+    public class TypeConversionException : Exception
+    {
+        public object Value { get; }
+        public Type TargetType { get; }
+
+        public TypeConversionException(string message, object value, Type targetType) : base(message)
+        {
+            Value = value;
+            TargetType = targetType;
+        }
+        
+        public TypeConversionException(string message, object value, Type targetType, Exception innerException) : base(message, innerException)
+        {
+            Value = value;
+            TargetType = targetType;
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/core/Elsa.Abstractions/Extensions/ObjectConverter.cs b/src/core/Elsa.Abstractions/Extensions/ObjectConverter.cs
index 1ed3bb420..fca1f74f3 100644
--- a/src/core/Elsa.Abstractions/Extensions/ObjectConverter.cs
+++ b/src/core/Elsa.Abstractions/Extensions/ObjectConverter.cs
@@ -1,5 +1,6 @@
 using System;
 using System.ComponentModel;
+using Elsa.Exceptions;
 using Newtonsoft.Json.Linq;
 using NodaTime;
 using NodaTime.Text;
@@ -53,8 +54,16 @@ namespace Elsa
                 if (underlyingSourceType != typeof(string))
                     return Enum.ToObject(underlyingTargetType, value);
             }
+
+            try
+            {
+                return Convert.ChangeType(value, underlyingTargetType);
+            }
+            catch (InvalidCastException e)
+            {
+                throw new TypeConversionException($"Failed to convert an object of type {sourceType} to {underlyingTargetType}", value, underlyingTargetType, e);
+            }
             
-            return Convert.ChangeType(value, underlyingTargetType);
         }
     }
 }
\ No newline at end of file