#75

Author: StefH

src/System.Linq.Dynamic.Core/DynamicClass.cs

@@ -187,9 +187,14 @@ private Dictionary<string, object> _properties
 
                     foreach (PropertyInfo pi in GetType().GetProperties(BindingFlags.Public | BindingFlags.Instance))
                     {
-                        int parameters = pi.GetGetMethod().GetParameters().Length;
-                        if (parameters == 0)
-                            _propertiesDictionary.Add(pi.Name, pi.GetValue(this, null));
+                        int parameters = pi.GetIndexParameters().Length;
+                        if (parameters > 0)
+                        {
+                            // The property is an indexer, skip this.
+                            continue;
+                        }
+
+                        _propertiesDictionary.Add(pi.Name, pi.GetValue(this, null));
                     }
                 }
 

test/System.Linq.Dynamic.Core.Tests/QueryableTests.GroupBy.cs

@@ -1,6 +1,8 @@
-using System.Collections.Generic;
+using NFluent;
+using System.Collections.Generic;
 using System.Linq.Dynamic.Core.Exceptions;
 using System.Linq.Dynamic.Core.Tests.Helpers.Models;
+using System.Reflection;
 using Xunit;
 
 namespace System.Linq.Dynamic.Core.Tests
@@ -23,6 +25,22 @@ public void GroupBy_Dynamic()
             Assert.Equal(testList.GroupBy(x => x.Profile.Age).Count(), byAgeReturnAll.Count());
         }
 
+        // https://github.com/StefH/System.Linq.Dynamic.Core/issues/75
+        [Fact]
+        public void GroupBy_Dynamic_Issue75()
+        {
+            var testList = User.GenerateSampleModels(100);
+
+            var resultDynamic = testList.AsQueryable().GroupBy("Profile.Age").Select("new (it.key as PropertyKey)");
+            var result = testList.GroupBy(e => e.Profile.Age).Select(e => new { PropertyKey = e.Key }).AsQueryable();
+
+            // I think this should be true, but it isn't. dynamicResult add System.Object Item [System.String] property.
+            PropertyInfo[] properties = result.ElementType.GetTypeInfo().GetProperties();
+            PropertyInfo[] propertiesDynamic = resultDynamic.ElementType.GetTypeInfo().GetProperties();
+
+            Check.That(propertiesDynamic.Length).IsStrictlyGreaterThan(properties.Length);
+        }
+
         [Fact]
         public void GroupByMany_Dynamic_LambdaExpressions()
         {

test/System.Linq.Dynamic.Core.Tests/System.Linq.Dynamic.Core.Tests.csproj

@@ -58,6 +58,7 @@
     <PackageReference Include="System.Threading.Tasks">
       <Version>4.3.0</Version>
     </PackageReference>
+    <PackageReference Include="System.Reflection.TypeExtensions" Version="4.3.0"/>
   </ItemGroup>
 
   <ItemGroup>