Regression tests for #13381 - NullReferenceException when materializi…

…ng a Query type on the right side of a left join

Issue has been fixed in earlier checkin.

Resolves #13381

test/EFCore.Cosmos.FunctionalTests/Query/NorthwindKeylessEntitiesQueryCosmosTest.cs

@@ -42,16 +42,10 @@ public override async Task KeylessEntity_where_simple(bool async)
 FROM root c
 WHERE ((c[""Discriminator""] = ""Customer"") AND (c[""City""] = ""London""))");
         }
-
-        [ConditionalFact]
+        
+        [ConditionalFact] // views are not supported
         public override void KeylessEntity_by_database_view()
         {
-            base.KeylessEntity_by_database_view();
-
-            AssertSql(
-                @"SELECT c[""ProductID""], c[""ProductName""], ""Food"" AS CategoryName
-FROM root c
-WHERE ((c[""Discriminator""] = ""Product"") AND NOT(c[""Discontinued""]))");
         }
 
         [ConditionalFact(Skip = "See issue#17246")]

test/EFCore.InMemory.FunctionalTests/Query/NorthwindKeylessEntitiesQueryInMemoryTest.cs

@@ -17,5 +17,14 @@ public NorthwindKeylessEntitiesQueryInMemoryTest(
         {
             //TestLoggerFactory.TestOutputHelper = testOutputHelper;
         }
+
+        // mapping to view not supported on InMemory
+        public override void KeylessEntity_by_database_view()
+        {
+        }
+
+        public override void Entity_mapped_to_view_on_right_side_of_join()
+        {
+        }
     }
 }

test/EFCore.Relational.Specification.Tests/TestModels/Northwind/NorthwindRelationalContext.cs

@@ -27,7 +27,7 @@ protected override void OnModelCreating(ModelBuilder modelBuilder)
             modelBuilder.Entity<CustomerOrderHistory>().HasKey(coh => coh.ProductName);
             modelBuilder.Entity<MostExpensiveProduct>().HasKey(mep => mep.TenMostExpensiveProducts);
 
-            modelBuilder.Entity<CustomerView>().HasNoKey().ToQuery(
+            modelBuilder.Entity<CustomerQuery>().HasNoKey().ToQuery(
                 () => CustomerQueries.FromSqlInterpolated(
                     $"SELECT [c].[CustomerID] + {_empty} as [CustomerID], [c].[Address], [c].[City], [c].[CompanyName], [c].[ContactName], [c].[ContactTitle], [c].[Country], [c].[Fax], [c].[Phone], [c].[PostalCode], [c].[Region] FROM [Customers] AS [c]"
                 ));
@@ -41,7 +41,7 @@ protected override void OnModelCreating(ModelBuilder modelBuilder)
                         .Select(
                             o => new OrderQuery { CustomerID = o.CustomerID }));
 
-            modelBuilder.Entity<ProductQuery>().HasNoKey().ToView("Alphabetical list of products");
+            modelBuilder.Entity<ProductView>().HasNoKey().ToView("Alphabetical list of products");
         }
     }
 }

test/EFCore.Specification.Tests/Query/NorthwindAggregateOperatorsQueryTestBase.cs

@@ -1549,7 +1549,7 @@ public virtual Task Array_cast_to_IEnumerable_Contains_with_constant(bool async)
         public virtual void Contains_over_keyless_entity_throws()
         {
             using var context = CreateContext();
-            Assert.Throws<InvalidOperationException>(() => context.CustomerQueries.Contains(new CustomerView()));
+            Assert.Throws<InvalidOperationException>(() => context.CustomerQueries.Contains(new CustomerQuery()));
         }
 
         [ConditionalTheory]

test/EFCore.Specification.Tests/Query/NorthwindAsyncSimpleQueryTestBase.cs

@@ -33,7 +33,7 @@ protected NorthwindAsyncSimpleQueryTestBase(TFixture fixture)
         public virtual async Task Query_backed_by_database_view()
         {
             using var context = CreateContext();
-            var results = await context.Set<ProductQuery>().ToArrayAsync();
+            var results = await context.Set<ProductView>().ToArrayAsync();
 
             Assert.Equal(69, results.Length);
         }

test/EFCore.Specification.Tests/Query/NorthwindKeylessEntitiesQueryTestBase.cs

@@ -31,7 +31,7 @@ public virtual Task KeylessEntity_simple(bool async)
         {
             return AssertQuery(
                 async,
-                ss => ss.Set<CustomerView>());
+                ss => ss.Set<CustomerQuery>());
         }
 
         [ConditionalTheory]
@@ -40,14 +40,14 @@ public virtual Task KeylessEntity_where_simple(bool async)
         {
             return AssertQuery(
                 async,
-                ss => ss.Set<CustomerView>().Where(c => c.City == "London"));
+                ss => ss.Set<CustomerQuery>().Where(c => c.City == "London"));
         }
 
         [ConditionalFact]
         public virtual void KeylessEntity_by_database_view()
         {
             using var context = CreateContext();
-            var results = context.Set<ProductQuery>().ToArray();
+            var results = context.Set<ProductView>().ToArray();
 
             Assert.Equal(69, results.Length);
         }
@@ -66,7 +66,7 @@ public virtual void KeylessEntity_with_nav_defining_query()
         {
             using var context = CreateContext();
             var results
-                = context.Set<CustomerQuery>()
+                = context.Set<CustomerQueryWithQueryFilter>()
                     .Where(cq => cq.OrderCount > 0)
                     .ToArray();
 
@@ -181,10 +181,23 @@ public virtual Task KeylesEntity_groupby(bool async)
         {
             return AssertQuery(
                 async,
-                ss => ss.Set<CustomerView>()
+                ss => ss.Set<CustomerQuery>()
                     .GroupBy(cv => cv.City)
                     .Select(g => new { g.Key, Count = g.Count(), Sum = g.Sum(e => e.Address.Length) }),
                 elementSorter: e => (e.Key, e.Count, e.Sum));
         }
+
+        [ConditionalFact]
+        public virtual void Entity_mapped_to_view_on_right_side_of_join()
+        {
+            using var context = CreateContext();
+
+            var results = (from o in context.Set<Order>()
+                           join pv in context.Set<ProductView>() on o.CustomerID equals pv.CategoryName into grouping
+                           from pv in grouping.DefaultIfEmpty()
+                           select new { Order = o, ProductView = pv }).ToList();
+
+            Assert.Equal(830, results.Count);
+        }
     }
 }

test/EFCore.Specification.Tests/Query/NorthwindQueryFixtureBase.cs

@@ -23,7 +23,7 @@ public IReadOnlyDictionary<Type, object> GetEntitySorters()
             => new Dictionary<Type, Func<object, object>>
             {
                 { typeof(Customer), e => ((Customer)e)?.CustomerID },
-                { typeof(CustomerView), e => ((CustomerView)e)?.CompanyName },
+                { typeof(CustomerQuery), e => ((CustomerQuery)e)?.CompanyName },
                 { typeof(Order), e => ((Order)e)?.OrderID },
                 { typeof(OrderQuery), e => ((OrderQuery)e)?.CustomerID },
                 { typeof(Employee), e => ((Employee)e)?.EmployeeID },

test/EFCore.Specification.Tests/Query/NorthwindSelectQueryTestBase.cs

@@ -1678,7 +1678,7 @@ public virtual Task Project_keyless_entity_FirstOrDefault_without_orderby(bool a
         {
             return AssertQuery(
                 async,
-                ss => ss.Set<Customer>().Select(c => ss.Set<CustomerView>().FirstOrDefault(cv => cv.CompanyName == c.CompanyName)));
+                ss => ss.Set<Customer>().Select(c => ss.Set<CustomerQuery>().FirstOrDefault(cv => cv.CompanyName == c.CompanyName)));
         }
 
         [ConditionalTheory]

test/EFCore.Specification.Tests/TestModels/Northwind/CustomerQuery.cs

@@ -1,12 +1,45 @@
-// Copyright (c) .NET Foundation. All rights reserved.
+// Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
+using System.ComponentModel.DataAnnotations.Schema;
+
 namespace Microsoft.EntityFrameworkCore.TestModels.Northwind
 {
     public class CustomerQuery
     {
         public string CompanyName { get; set; }
-        public int OrderCount { get; set; }
-        public string SearchTerm { get; set; }
+        public string ContactName { get; set; }
+        public string ContactTitle { get; set; }
+        public string Address { get; set; }
+        public string City { get; set; }
+
+        [NotMapped]
+        public bool IsLondon => City == "London";
+
+        protected bool Equals(CustomerQuery other)
+            => string.Equals(CompanyName, other.CompanyName);
+
+        public override bool Equals(object obj)
+        {
+            if (obj is null)
+            {
+                return false;
+            }
+
+            return ReferenceEquals(this, obj)
+                ? true
+                : obj.GetType() == GetType()
+                && Equals((CustomerQuery)obj);
+        }
+
+        public static bool operator ==(CustomerQuery left, CustomerQuery right)
+            => Equals(left, right);
+
+        public static bool operator !=(CustomerQuery left, CustomerQuery right)
+            => !Equals(left, right);
+
+        public override int GetHashCode()
+            // ReSharper disable once NonReadonlyMemberInGetHashCode
+            => CompanyName?.GetHashCode() ?? 0;
     }
 }

test/EFCore.Specification.Tests/TestModels/Northwind/CustomerQueryWithQueryFilter.cs

@@ -0,0 +1,12 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+namespace Microsoft.EntityFrameworkCore.TestModels.Northwind
+{
+    public class CustomerQueryWithQueryFilter
+    {
+        public string CompanyName { get; set; }
+        public int OrderCount { get; set; }
+        public string SearchTerm { get; set; }
+    }
+}

test/EFCore.Specification.Tests/TestModels/Northwind/NorthwindContext.cs

@@ -20,7 +20,7 @@ public NorthwindContext(DbContextOptions options)
         public virtual DbSet<Order> Orders { get; set; }
         public virtual DbSet<OrderDetail> OrderDetails { get; set; }
         public virtual DbSet<Product> Products { get; set; }
-        public virtual DbSet<CustomerView> CustomerQueries { get; set; }
+        public virtual DbSet<CustomerQuery> CustomerQueries { get; set; }
 
         protected override void OnModelCreating(ModelBuilder modelBuilder)
         {
@@ -75,12 +75,12 @@ protected override void OnModelCreating(ModelBuilder modelBuilder)
                 });
 
             modelBuilder
-                .Entity<CustomerView>()
+                .Entity<CustomerQuery>()
                 .HasNoKey()
                 .ToQuery(
                     () => Customers
                         .Select(
-                            c => new CustomerView
+                            c => new CustomerQuery
                             {
                                 Address = c.Address,
                                 City = c.City,
@@ -112,7 +112,7 @@ protected override void OnModelCreating(ModelBuilder modelBuilder)
                             }));
 
             modelBuilder
-                .Entity<CustomerQuery>()
+                .Entity<CustomerQueryWithQueryFilter>()
                 .HasNoKey()
                 .HasQueryFilter(cq => cq.CompanyName.StartsWith(_searchTerm))
                 .ToQuery(
@@ -121,7 +121,7 @@ protected override void OnModelCreating(ModelBuilder modelBuilder)
                             .Include(c => c.Orders) // ignored
                             .Select(
                                 c =>
-                                    new CustomerQuery
+                                    new CustomerQueryWithQueryFilter
                                     {
                                         CompanyName = c.CompanyName,
                                         OrderCount = c.Orders.Count(),

test/EFCore.Specification.Tests/TestModels/Northwind/NorthwindData.cs

@@ -13,7 +13,7 @@ namespace Microsoft.EntityFrameworkCore.TestModels.Northwind
     public partial class NorthwindData : ISetSource
     {
         private readonly Customer[] _customers;
-        private readonly CustomerView[] _customerViews;
+        private readonly CustomerQuery[] _customerQueries;
         private readonly Employee[] _employees;
         private readonly Product[] _products;
         private readonly Order[] _orders;
@@ -28,14 +28,15 @@ public NorthwindData()
             _orders = CreateOrders();
             _orderDetails = CreateOrderDetails();
 
-            var customerViews = new List<CustomerView>();
+            var customerQueries = new List<CustomerQuery>();
+            var customerQueriesWithQueryFilter = new List<CustomerQueryWithQueryFilter>();
 
             foreach (var customer in _customers)
             {
                 customer.Orders = new List<Order>();
 
-                customerViews.Add(
-                    new CustomerView
+                customerQueries.Add(
+                    new CustomerQuery
                     {
                         Address = customer.Address,
                         City = customer.City,
@@ -45,7 +46,7 @@ public NorthwindData()
                     });
             }
 
-            _customerViews = customerViews.ToArray();
+            _customerQueries = customerQueries.ToArray();
 
             foreach (var product in _products)
             {
@@ -114,9 +115,9 @@ public IQueryable<TEntity> Set<TEntity>()
                 return (IQueryable<TEntity>)_products.AsQueryable();
             }
 
-            if (typeof(TEntity) == typeof(CustomerView))
+            if (typeof(TEntity) == typeof(CustomerQuery))
             {
-                return (IQueryable<TEntity>)_customerViews.AsQueryable();
+                return (IQueryable<TEntity>)_customerQueries.AsQueryable();
             }
 
             if (typeof(TEntity) == typeof(OrderQuery))

test/EFCore.Specification.Tests/TestModels/Northwind/ProductView.cs

@@ -0,0 +1,12 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+namespace Microsoft.EntityFrameworkCore.TestModels.Northwind
+{
+    public class ProductView
+    {
+        public int ProductID { get; set; }
+        public string ProductName { get; set; }
+        public string CategoryName { get; set; }
+    }
+}

test/EFCore.SqlServer.FunctionalTests/Query/NorthwindKeylessEntitiesQuerySqlServerTest.cs

@@ -45,15 +45,9 @@ public override void KeylessEntity_by_database_view()
         {
             base.KeylessEntity_by_database_view();
 
-            // See issue#17804
-            // when we have defining query and ToView, defining query wins
-            //            AssertSql(
-            //                @"SELECT [a].[CategoryName], [a].[ProductID], [a].[ProductName]
-            //FROM [Alphabetical list of products] AS [a]");
             AssertSql(
-                @"SELECT [p].[ProductID], [p].[ProductName], N'Food' AS [CategoryName]
-FROM [Products] AS [p]
-WHERE [p].[Discontinued] <> CAST(1 AS bit)");
+                @"SELECT [a].[CategoryName], [a].[ProductID], [a].[ProductName]
+FROM [Alphabetical list of products] AS [a]");
         }
 
         public override void KeylessEntity_with_nav_defining_query()
@@ -164,6 +158,16 @@ public override async Task KeylesEntity_groupby(bool async)
 GROUP BY [c].[City]");
         }
 
+        public override void Entity_mapped_to_view_on_right_side_of_join()
+        {
+            base.Entity_mapped_to_view_on_right_side_of_join();
+
+            AssertSql(
+                @"SELECT [o].[OrderID], [o].[CustomerID], [o].[EmployeeID], [o].[OrderDate], [a].[CategoryName], [a].[ProductID], [a].[ProductName]
+FROM [Orders] AS [o]
+LEFT JOIN [Alphabetical list of products] AS [a] ON [o].[CustomerID] = [a].[CategoryName]");
+        }
+
         private void AssertSql(params string[] expected)
             => Fixture.TestSqlLoggerFactory.AssertBaseline(expected);