support multiple selects

Author: Ihar Yakimush

SolrNet.Linq.IntegrationTests/SelectTests.cs

@@ -4,6 +4,7 @@
 using System.Runtime.Serialization;
 using SolrNet.Attributes;
 using SolrNet.Commands.Parameters;
+using SolrNet.Exceptions;
 using Xunit;
 
 namespace SolrNet.Linq.IntegrationTests
@@ -38,6 +39,25 @@ public void AnonymousClass()
             Assert.NotNull(t1);
         }
 
+        [Fact]
+        public void MultipleSelects()
+        {
+            var t1 = Product.SolrOperations.Value.AsQueryable(lo => lo.SetupQueryOptions = qo =>
+                {
+                    Assert.Equal(1, qo.Fields.Count);
+                    Assert.Equal(3, qo.FilterQueries.Count);
+                    Assert.Equal("Id:id", qo.Fields.ElementAt(0));
+                }).Where(p => p.Id != null)
+                .Select(p => new {p.Id, p.Price, p.Categories, Qwe = Math.Pow(2, 2)})
+                .Where(arg => arg.Categories.Any(s => s == "electronics"))
+                .OrderBy(arg => arg.Id)
+                .Select(arg => new {arg.Id})
+                .FirstOrDefault(arg2 => arg2.Id != null);
+
+            Assert.NotNull(t1);
+        }
+
+
         [Fact]
         public void Product2()
         {
@@ -53,7 +73,9 @@ public void Product2()
                     Assert.Equal("id", qo.OrderBy.ElementAt(0).FieldName);
                     Assert.Equal("pow(2,2)", qo.OrderBy.ElementAt(1).FieldName);
                     Assert.Equal("pow(2,3)", qo.OrderBy.ElementAt(2).FieldName);
-                    
+
+                    Assert.Equal(2, qo.FilterQueries.Count);
+
                 }).Where(p => p.Id != null)
                 .Select(p => new Product2 {Id = p.Id, Price = p.Price, Categories = p.Categories, Qwe = Math.Pow(2, 2)})
                 .Where(arg => arg.Categories.Any(s => s == "electronics"))
@@ -78,5 +100,28 @@ public void Product2()
             Assert.Single(t3);
             Assert.Equal(t1.Id, t3.Single().Id);
         }
+
+        [Fact]
+        public void Product2WithMemberProduct()
+        {
+            Assert.Throws<SolrConnectionException>(() => Product.SolrOperations.Value.AsQueryable(lo => lo.SetupQueryOptions = qo =>
+                {
+                    Assert.Equal(4, qo.Fields.Count);
+                    Assert.Equal("Price:sum(price,1)", qo.Fields.ElementAt(0));
+                    Assert.Equal("Qwe:pow(2,2)", qo.Fields.ElementAt(1));
+                    Assert.Equal("Id:id", qo.Fields.ElementAt(2));
+                    Assert.Equal("Categories:cat", qo.Fields.ElementAt(3));
+
+                    Assert.Equal(3, qo.OrderBy.Count);
+                    Assert.Equal("id", qo.OrderBy.ElementAt(0).FieldName);
+                    Assert.Equal("sum(price,1)", qo.OrderBy.ElementAt(1).FieldName);
+                    Assert.Equal("pow(2,3)", qo.OrderBy.ElementAt(2).FieldName);
+                }).Where(p => p.Id != null)
+                .Select(p =>
+                    new Product2 {Id = p.Id, Price = p.Price + 1, Categories = p.Categories, Qwe = Math.Pow(2, 2)})
+                .Where(arg => arg.Categories.Any(s => s == "electronics"))
+                .OrderBy(arg => arg.Id).ThenBy(arg => arg.Price).ThenBy(arg => Math.Pow(2, 3))
+                .FirstOrDefault());
+        }
     }
 }

SolrNet.Linq/Expressions/NodeTypeHelpers/SelectMethod.cs

@@ -35,6 +35,7 @@ public static bool TryVisitSelect(this MethodCallExpression node, QueryOptions o
 
                     if (newContext != null)
                     {
+                        options.Fields.Clear();
                         foreach (var pairValue in newContext.Aliases.Concat(newContext.Members))
                         {
                             options.Fields.Add($"{pairValue.Key.Name}:{pairValue.Value}");

SolrNet.Linq/Impl/AnonymousTypeActivator.cs

@@ -0,0 +1,35 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Reflection;
+using SolrNet.Impl;
+
+namespace SolrNet.Linq.Impl
+{
+    public class AnonymousTypeActivator<T> : ISolrDocumentActivator<T>
+    {
+        public T Create()
+        {
+            Type type = typeof(T);
+
+            ConstructorInfo[] ctors = type.GetConstructors();
+
+            // Has parameter less ctor, so use activator
+            if (ctors.Any(info => !info.GetParameters().Any()))
+            {
+                return Activator.CreateInstance<T>();
+            }
+
+            // try to invoke ctor with minimum args, providing default values
+
+            ConstructorInfo ctor = ctors.OrderBy(info => info.GetParameters().Length).First();
+            List<object> args = new List<object>();
+            foreach (var p in ctor.GetParameters())
+            {
+                args.Add(p.ParameterType.IsValueType ? Activator.CreateInstance(p.ParameterType) : null);
+            }
+
+            return (T)Activator.CreateInstance(type, args.ToArray());
+        }
+    }
+}

SolrNet.Linq/Impl/ExecuterExtensions.cs

@@ -29,7 +29,7 @@ public static IExecuter<TNew> ChangeType<TNew, TOld>(this IExecuter<TOld> execut
 
                 ISolrAbstractResponseParser<TNew> parser =
                     new DefaultResponseParser<TNew>(
-                        new SolrDocumentResponseParser<TNew>(mapper, sdpv, new SolrDocumentActivator<TNew>()));
+                        new SolrDocumentResponseParser<TNew>(mapper, sdpv, new AnonymousTypeActivator<TNew>()));
 
                 SolrQueryExecuter<TNew> newExecuter = new SolrQueryExecuter<TNew>(parser, connection, serializer,
                     facetQuerySerializer,