#161: Add support for nested collection types

MappingGenerator/MappingGenerator/MappingGenerator.Test/ExplicitConversions/ExplicitConversionTestCases.resx

@@ -154,4 +154,10 @@
   <data name="_006_ExplicitConversionForInvalidAssigmentInInitBlockReuseInstance_FIXED" type="System.Resources.ResXFileRef, System.Windows.Forms">
     <value>TestCaseData\006_ExplicitConversionForInvalidAssigmentInInitBlockReuseInstance_FIXED.txt;System.String, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089;utf-8</value>
   </data>
+  <data name="_007_ExplicitConversionForValueCollection" type="System.Resources.ResXFileRef, System.Windows.Forms">
+    <value>TestCaseData\007_ExplicitConversionForValueCollection.txt;System.String, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089;utf-8</value>
+  </data>
+  <data name="_007_ExplicitConversionForValueCollection_FIXED" type="System.Resources.ResXFileRef, System.Windows.Forms">
+    <value>TestCaseData\007_ExplicitConversionForValueCollection_FIXED.txt;System.String, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089;utf-8</value>
+  </data>
 </root>

MappingGenerator/MappingGenerator/MappingGenerator.Test/ExplicitConversions/ExplicitConversionTests.cs

@@ -46,6 +46,12 @@ public void should_be_able_to_generate_conversion_by_re_using_instance_inside_in
         {
             TestCodeFix(ExplicitConversionTestCases._006_ExplicitConversionForInvalidAssigmentInInitBlockReuseInstance, ExplicitConversionTestCases._006_ExplicitConversionForInvalidAssigmentInInitBlockReuseInstance_FIXED, ExplicitConversionCodeFixProvider.CS0029, 1);
         }
+
+        [Test]
+        public void should_be_able_to_generate_conversion_for_value_collection()
+        {
+            TestCodeFix(ExplicitConversionTestCases._007_ExplicitConversionForValueCollection, ExplicitConversionTestCases._007_ExplicitConversionForValueCollection_FIXED, ExplicitConversionCodeFixProvider.CS0029, 0);
+        }
         protected override string LanguageName => LanguageNames.CSharp;
 
         protected override CodeFixProvider CreateProvider()

MappingGenerator/MappingGenerator/MappingGenerator.Test/ExplicitConversions/TestCaseData/007_ExplicitConversionForValueCollection.txt

@@ -0,0 +1,17 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace MappingGenerator.Test.ExplicitConversions.TestCaseData
+{
+    public class Source { }
+    public class Destination { }
+
+    public class SampleMapper
+    {
+        public IEnumerable<Destination> Example(Dictionary<string, Source> source)
+        {
+            return [|source.Values|];
+        }
+    }
+}

MappingGenerator/MappingGenerator/MappingGenerator.Test/ExplicitConversions/TestCaseData/007_ExplicitConversionForValueCollection_FIXED.txt

@@ -0,0 +1,17 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace MappingGenerator.Test.ExplicitConversions.TestCaseData
+{
+    public class Source { }
+    public class Destination { }
+
+    public class SampleMapper
+    {
+        public IEnumerable<Destination> Example(Dictionary<string, Source> source)
+        {
+            return source.Values.Select(sourceValue => new Destination());
+        }
+    }
+}

MappingGenerator/MappingGenerator/MappingGenerator/Mappings/MappingEngine.cs

@@ -438,6 +438,11 @@ public async Task<ExpressionSyntax> CreateMappingLambdaAsync(string lambdaParame
 
         private static SyntaxNode AddMaterializeCollectionInvocation(SyntaxGenerator generator, SyntaxNode sourceAccess, ITypeSymbol targetListType, bool isSourceNullable)
         {
+            if (targetListType.TypeKind == TypeKind.Interface && targetListType.Name == "IEnumerable")
+            {
+                return sourceAccess;
+            }
+
             var materializeFunction =  GetCollectionMaterializeFunction(targetListType);
             var toListAccess = SyntaxFactoryExtensions.CreateMemberAccessExpression((ExpressionSyntax)sourceAccess, isSourceNullable, materializeFunction);
             return generator.InvocationExpression(toListAccess);

MappingGenerator/MappingGenerator/MappingGenerator/Mappings/MappingHelper.cs

@@ -1,7 +1,6 @@
 using System;
 using System.Linq;
 using MappingGenerator.Features.Refactorings;
-using MappingGenerator.Mappings.SourceFinders;
 using MappingGenerator.RoslynHelpers;
 using Microsoft.CodeAnalysis;
 using Microsoft.CodeAnalysis.CSharp;
@@ -45,6 +44,16 @@ public static AnnotatedType GetElementType(ITypeSymbol collectionType)
                         }
                         return GetElementType(namedType.BaseType);
                     }
+
+                    //INFO: Type is reported as generic when containing type is generic
+                    if (namedType.Arity == 0 && namedType.ContainingType?.TypeKind is {} containerType && (containerType == TypeKind.Class || containerType == TypeKind.Structure))
+                    {
+                        if (namedType.Interfaces.FirstOrDefault(x => x.Name == "IEnumerable" && x.IsGenericType) is {} enumerable)
+                        {
+                            return new AnnotatedType(enumerable.TypeParameters[0]);
+                        }
+                    }
+
                     return new AnnotatedType(namedType.TypeArguments[0]);
                 case IArrayTypeSymbol arrayType:
                     return new AnnotatedType(arrayType.ElementType);