Applying similar fixes for Artihmetic operators to handle overflow, per https://cql.hl7.org/09-b-cqlreference.html#subtract and https://cql.hl7.org/09-b-cqlreference.html#add:~:text=If%20the%20result%20of%20the%20addition%20cannot%20be%20represented%20(i.e.%20arithmetic%20overflow)%2C%20the%20result%20is%20null.

Author: igajurelNCQA

Cql/Cql.Runtime/Operators/CqlOperators.ArithmeticOperators.cs

@@ -54,18 +54,42 @@ internal partial class CqlOperators
         public int? Add(int? left, int? right)
         {
             if (left == null || right == null) return null;
-            else return left + right;
+            try
+            {
+                return left + right;
+            }
+            catch (OverflowException e)
+            {
+                Message(new { left, right, e }, "CqlOperators.ArithmeticOperators.Add", "Warning", "Ignored overflow errors from type integer addition, returned null.");
+                return null;
+            }
         }
 
         public long? Add(long? left, long? right)
         {
             if (left == null || right == null) return null;
-            else return left + right;
+            try
+            {
+                return left + right;
+            }
+            catch (OverflowException e)
+            {
+                Message(new { left, right, e }, "CqlOperators.ArithmeticOperators.Add", "Warning", "Ignored overflow errors from type long addition, returned null.");
+                return null;
+            }
         }
         public decimal? Add(decimal? left, decimal? right)
         {
             if (left == null || right == null) return null;
-            else return left + right;
+            try
+            {
+                return left + right;
+            }
+            catch (OverflowException e)
+            {
+                Message(new { left, right, e }, "CqlOperators.ArithmeticOperators.Add", "Warning", "Ignored overflow errors from type decimal addition, returned null.");
+                return null;
+            }
         }
 
         public CqlQuantity? Add(CqlQuantity? left, CqlQuantity? right)
@@ -674,18 +698,42 @@ internal partial class CqlOperators
         public int? Subtract(int? left, int? right)
         {
             if (left == null || right == null) return null;
-            else return left - right;
+            try
+            {
+                return left - right;
+            }
+            catch (OverflowException e)
+            {
+                Message(new { left, right, e }, "CqlOperators.ArithmeticOperators.Subtract", "Warning", "Ignored overflow errors from type integer subtraction, returned null.");
+                return null;
+            }
         }
 
         public long? Subtract(long? left, long? right)
         {
             if (left == null || right == null) return null;
-            else return left - right;
+            try
+            {
+                return left - right;
+            }
+            catch (OverflowException e)
+            {
+                Message(new { left, right, e }, "CqlOperators.ArithmeticOperators.Subtract", "Warning", "Ignored overflow errors from type long subtraction, returned null.");
+                return null;
+            }
         }
         public decimal? Subtract(decimal? left, decimal? right)
         {
             if (left == null || right == null) return null;
-            else return left - right;
+            try
+            {
+                return left - right;
+            }
+            catch (OverflowException e)
+            {
+                Message(new { left, right, e }, "CqlOperators.ArithmeticOperators.Subtract", "Warning", "Ignored overflow errors from type decimal subtraction, returned null.");
+                return null;
+            }
         }
 
         public CqlQuantity? Subtract(CqlQuantity? left, CqlQuantity? right)

Cql/Cql.Runtime/Operators/CqlOperators.DateTimeOperators.cs

@@ -27,7 +27,7 @@ internal partial class CqlOperators
             }
             catch (ArgumentOutOfRangeException e)
             {
-                Message(new { left, right, e }, "CqlOperators.Add", "Warning", "Ignored overflow errors from date addition, returned null.");
+                Message(new { left, right, e }, "CqlOperators.DateTimeOperators.Add", "Warning", "Ignored overflow errors from date addition, returned null.");
                 return null;
             }
         }
@@ -41,7 +41,7 @@ internal partial class CqlOperators
             }
             catch (ArgumentOutOfRangeException e)
             {
-                Message(new { left, right, e }, "CqlOperators.Add", "Warning", "Ignored overflow errors from datetime addition, returned null.");
+                Message(new { left, right, e }, "CqlOperators.DateTimeOperators.Add", "Warning", "Ignored overflow errors from datetime addition, returned null.");
                 return null;
             }
         }
@@ -56,7 +56,7 @@ internal partial class CqlOperators
             }
             catch (ArgumentOutOfRangeException e)
             {
-                Message(new { left, right, e }, "CqlOperators.Add", "Warning", "Ignored overflow errors from time addition, returned null.");
+                Message(new { left, right, e }, "CqlOperators.DateTimeOperators.Add", "Warning", "Ignored overflow errors from time addition, returned null.");
                 return null;
             }
         }
@@ -351,7 +351,7 @@ internal partial class CqlOperators
             }
             catch (ArgumentOutOfRangeException e)
             {
-                Message(new { left, right, e }, "CqlOperators.Subtract", "Warning", "Ignored overflow errors from date subtraction, returned null.");
+                Message(new { left, right, e }, "CqlOperators.DateTimeOperators.Subtract", "Warning", "Ignored overflow errors from date subtraction, returned null.");
                 return null;
             }
         }
@@ -366,7 +366,7 @@ internal partial class CqlOperators
             }
             catch (ArgumentOutOfRangeException e)
             {
-                Message(new { left, right, e }, "CqlOperators.Subtract", "Warning", "Ignored overflow errors from datetime subtraction, returned null.");
+                Message(new { left, right, e }, "CqlOperators.DateTimeOperators.Subtract", "Warning", "Ignored overflow errors from datetime subtraction, returned null.");
                 return null;
             }
         }
@@ -381,7 +381,7 @@ internal partial class CqlOperators
             }
             catch (ArgumentOutOfRangeException e)
             {
-                Message(new { left, right, e }, "CqlOperators.Subtract", "Warning", "Ignored overflow errors from time subtraction, returned null.");
+                Message(new { left, right, e }, "CqlOperators.DateTimeOperators.Subtract", "Warning", "Ignored overflow errors from time subtraction, returned null.");
                 return null;
             }
         }