Include member name for better exception message

DynamoDBGenerator.SourceGenerator.Tests/DynamoDBDocumentTests/Deserialize/MissingValueTests.cs

@@ -1,5 +1,6 @@
 using Amazon.DynamoDBv2.Model;
 using DynamoDBGenerator.Attributes;
+using DynamoDBGenerator.Exceptions;
 namespace DynamoDBGenerator.SourceGenerator.Tests.DynamoDBDocumentTests.Deserialize;
 
 [DynamoDBMarshaller(typeof(RequiredReferenceTypeValueMissingClass))]
@@ -11,14 +12,14 @@ public partial class MissingValueTests
     public void Deserialize_RequiredReferenceTypeValueMissingClass_NoKeyValueProvidedShouldThrow()
     {
         var act = () => RequiredReferenceTypeValueMissingClassMarshaller.Unmarshall(new Dictionary<string, AttributeValue>());
-        act.Should().Throw<ArgumentNullException>();
+        act.Should().Throw<DynamoDBMarshallingException>();
     }
 
     [Fact]
     public void Deserialize_RequiredReferenceTypeValueMissingClass_KeyWithoutValueProvidedShouldThrow()
     {
         var act = () => RequiredReferenceTypeValueMissingClassMarshaller.Unmarshall(new Dictionary<string, AttributeValue> {{"RequiredProperty", new AttributeValue {S = null}}});
-        act.Should().Throw<ArgumentNullException>();
+        act.Should().Throw<DynamoDBMarshallingException>();
     }
 
     [Fact]
@@ -39,14 +40,14 @@ public void Deserialize_OptionalReferenceTypeValueMissingClass_NoKeyValueProvide
     public void Deserialize_RequiredValueTypeValueMissingClass_KeyWithoutValueProvidedShouldThrow()
     {
         var act = () => RequiredValueTypeValueMissingClassMarshaller.Unmarshall(new Dictionary<string, AttributeValue> {{"RequiredProperty", new AttributeValue {N = null}}});
-        act.Should().Throw<ArgumentNullException>();
+        act.Should().Throw<DynamoDBMarshallingException>();
     }
 
     [Fact]
     public void Deserialize_RequiredValueTypeValueMissingClass_NoKeyValueProvidedShouldThrow()
     {
         var act = () => RequiredValueTypeValueMissingClassMarshaller.Unmarshall(new Dictionary<string, AttributeValue>());
-        act.Should().Throw<ArgumentNullException>();
+        act.Should().Throw<DynamoDBMarshallingException>().WithMessage("The data member is not supposed to be null, to allow this; make the data member nullable. (Data member 'RequiredProperty')");
     }
 }
 

DynamoDBGenerator.SourceGenerator.Tests/DynamoDBDocumentTests/Deserialize/Types/EnumTests.cs

@@ -1,5 +1,6 @@
 using Amazon.DynamoDBv2.Model;
 using DynamoDBGenerator.Attributes;
+using DynamoDBGenerator.Exceptions;
 namespace DynamoDBGenerator.SourceGenerator.Tests.DynamoDBDocumentTests.Deserialize.Types;
 
 [DynamoDBMarshaller(typeof(WeekDayClass))]
@@ -53,7 +54,7 @@ public void Deserialize_WeekDayClass_NoKeyValue()
             .Unmarshall(new Dictionary<string, AttributeValue>())
             .Should();
 
-        act.Should().Throw<ArgumentNullException>();
+        act.Should().Throw<DynamoDBMarshallingException>();
 
     }
 
@@ -64,7 +65,7 @@ public void Deserialize_WeekDayClass_NoValueProvided()
             .Unmarshall(new Dictionary<string, AttributeValue> {{nameof(WeekDayClass.DayOfWeek), new AttributeValue {N = null}}})
             .Should();
 
-        act.Should().Throw<ArgumentNullException>();
+        act.Should().Throw<DynamoDBMarshallingException>();
 
     }
     [Fact]

DynamoDBGenerator.SourceGenerator/Constants.cs

@@ -24,7 +24,6 @@ public static class Errors
     public const int MaxMethodNameLenght = 511;
 
     public const string NotNullErrorMessage = "The data member is not supposed to be null, to allow this; make the data member nullable.";
-
 }
 
 public static class ConstantExtensions

DynamoDBGenerator.SourceGenerator/Extensions/CodeGeneration/DynamoDBDocument/Generation.cs

@@ -1,3 +1,6 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
 using Amazon.DynamoDBv2.Model;
 using DynamoDBGenerator.SourceGenerator.Types;
 using Microsoft.CodeAnalysis;
@@ -96,9 +99,9 @@ private Assignment BuildList(in ITypeSymbol elementType, in string accessPattern
         return new Assignment(in outerAssignment, in elementType, innerAssignment.HasExternalDependency);
     }
 
-    private Assignment BuildPocoList(in SingleGeneric singleGeneric, in string? operation, in string accessPattern, in string defaultCause)
+    private Assignment BuildPocoList(in SingleGeneric singleGeneric, in string? operation, in string accessPattern, in string defaultCause, in string memberName)
     {
-        var innerAssignment = DataMemberAssignment(singleGeneric.T, "y");
+        var innerAssignment = DataMemberAssignment(singleGeneric.T, "y", in memberName);
         var outerAssignment = $"{accessPattern} switch {{ {{ L: {{ }} x }} => x.Select(y => {innerAssignment.Value}){operation}, {defaultCause} }}";
 
         return new Assignment(in outerAssignment, singleGeneric.T, innerAssignment.HasExternalDependency);
@@ -217,12 +220,13 @@ public string CreateDynamoDbDocumentProperty(Accessibility accessibility)
         {@class}";
     }
 
-    private Assignment DataMemberAssignment(in ITypeSymbol type, in string pattern)
+    private Assignment DataMemberAssignment(in ITypeSymbol type, in string pattern, in string memberName)
     {
-        var defaultCase = type.IsNullable() ? "_ => null" : @$"_ => throw new ArgumentNullException(""{Constants.NotNullErrorMessage}"")";
-        return Execution(in type, in pattern, defaultCase);
+
+        var defaultCase = type.IsNullable() ? "_ => null" : @$"_ => throw new DynamoDBMarshallingException(""{memberName}"", ""{Constants.NotNullErrorMessage}"")";
+        return Execution(in type, in pattern, defaultCase, in memberName);
 
-        Assignment Execution(in ITypeSymbol typeSymbol, in string accessPattern, string @default)
+        Assignment Execution(in ITypeSymbol typeSymbol, in string accessPattern, string @default, in string memberName)
         {
             if (typeSymbol.GetKnownType() is not { } knownType) return ExternalAssignment(in typeSymbol, in accessPattern);
 
@@ -252,15 +256,15 @@ Assignment Execution(in ITypeSymbol typeSymbol, in string accessPattern, string
                 },
                 SingleGeneric singleGeneric => singleGeneric.Type switch
                 {
-                    SingleGeneric.SupportedType.Nullable => Execution(singleGeneric.T, in accessPattern, @default),
+                    SingleGeneric.SupportedType.Nullable => Execution(singleGeneric.T, in accessPattern, @default, in memberName),
                     SingleGeneric.SupportedType.Set => BuildPocoSet(singleGeneric.T, in accessPattern, in @default),
-                    SingleGeneric.SupportedType.Array => BuildPocoList(in singleGeneric, ".ToArray()", in accessPattern, in @default),
-                    SingleGeneric.SupportedType.ICollection => BuildPocoList(in singleGeneric, ".ToList()", in accessPattern, in @default),
-                    SingleGeneric.SupportedType.IReadOnlyCollection => BuildPocoList(in singleGeneric, ".ToArray()", in accessPattern, in @default),
-                    SingleGeneric.SupportedType.IEnumerable => BuildPocoList(in singleGeneric, null, in accessPattern, in @default),
+                    SingleGeneric.SupportedType.Array => BuildPocoList(in singleGeneric, ".ToArray()", in accessPattern, in @default, in memberName),
+                    SingleGeneric.SupportedType.ICollection => BuildPocoList(in singleGeneric, ".ToList()", in accessPattern, in @default, in memberName),
+                    SingleGeneric.SupportedType.IReadOnlyCollection => BuildPocoList(in singleGeneric, ".ToArray()", in accessPattern, in @default, in memberName),
+                    SingleGeneric.SupportedType.IEnumerable => BuildPocoList(in singleGeneric, null, in accessPattern, in @default, in memberName),
                     _ => throw new ArgumentOutOfRangeException(typeSymbol.ToDisplayString())
                 },
-                KeyValueGeneric keyValueGeneric => StringKeyedPocoGeneric(in keyValueGeneric, in accessPattern, @default),
+                KeyValueGeneric keyValueGeneric => StringKeyedPocoGeneric(in keyValueGeneric, in accessPattern, in @default, in memberName),
                 _ => null
             };
 
@@ -564,7 +568,7 @@ private Conversion StaticPocoFactory(ITypeSymbol type)
         {
             var assignments = typeSymbol
                 .GetDynamoDbProperties()
-                .Select(x => (DDB: x, Assignment: DataMemberAssignment(x.DataMember.Type, @$"{paramReference}.GetValueOrDefault(""{x.AttributeName}"")")))
+                .Select(x => (DDB: x, Assignment: DataMemberAssignment(x.DataMember.Type, @$"{paramReference}.GetValueOrDefault(""{x.AttributeName}"")", x.DataMember.Name)))
                 .ToArray();
 
             if (typeSymbol.IsTupleType)
@@ -653,21 +657,21 @@ _ when namedTypeSymbol.InstanceConstructors
 
     }
 
-    private Assignment? StringKeyedPocoGeneric(in KeyValueGeneric keyValueGeneric, in string accessPattern, string defaultCase)
+    private Assignment? StringKeyedPocoGeneric(in KeyValueGeneric keyValueGeneric, in string accessPattern, in string defaultCase, in string memberName)
     {
         switch (keyValueGeneric)
         {
             case {TKey: not {SpecialType: SpecialType.System_String}}:
                 return null;
             case {Type: KeyValueGeneric.SupportedType.LookUp}:
-                var lookupValueAssignment = DataMemberAssignment(keyValueGeneric.TValue, "y.z");
+                var lookupValueAssignment = DataMemberAssignment(keyValueGeneric.TValue, "y.z", in memberName);
                 return new Assignment(
                     $"{accessPattern} switch {{ {{ M: {{ }} x }} => x.SelectMany(y => y.Value.L, (y, z) => (y.Key, z)).ToLookup(y => y.Key, y => {lookupValueAssignment.Value}), {defaultCase} }}",
                     keyValueGeneric.TValue,
                     lookupValueAssignment.HasExternalDependency
                 );
             case {Type: KeyValueGeneric.SupportedType.Dictionary}:
-                var dictionaryValueAssignment = DataMemberAssignment(keyValueGeneric.TValue, "y.Value");
+                var dictionaryValueAssignment = DataMemberAssignment(keyValueGeneric.TValue, "y.Value", in memberName);
                 return new Assignment(
                     $@"{accessPattern} switch {{ {{ M: {{ }} x }} => x.ToDictionary(y => y.Key, y => {dictionaryValueAssignment.Value}), {defaultCase} }}",
                     keyValueGeneric.TValue,

DynamoDBGenerator/Exceptions/DynamoDBMarshallingException.cs

@@ -8,4 +8,4 @@ public DynamoDBMarshallingException(string memberName, string message) : base(me
     {
         MemberName = memberName;
     }
-}
+}

SampleApp/Program.cs

@@ -3,20 +3,15 @@
 using Amazon.DynamoDBv2.Model;
 using BenchmarkDotNet.Attributes;
 using BenchmarkDotNet.Running;
-using DynamoDBGenerator;
 using DynamoDBGenerator.Attributes;
 using DynamoDBGenerator.Extensions;
-using static SampleApp.Repository.PersonEntityMarshallerImplementation;
-using PutItemRequest = Amazon.DynamoDBv2.Model.PutItemRequest;
 
 namespace SampleApp;
 
 internal static class Program
 {
-    private static IDynamoDBClient<PersonEntity, PersonEntity, PersonEntityName, PersonEntityValue> _toDynamoDBClient;
     public static void Main()
     {
-        _toDynamoDBClient = new Repository().PersonEntityMarshaller.ToDynamoDBClient("MyTable", new AmazonDynamoDBClient());
         BenchmarkRunner.Run<Marshalling>();
     }