Support Skip/Take with single-level grouping (#404)

Author: AlekseyMartynov

net/DevExtreme.AspNet.Data.Tests.Common/RemoteGroupCountTestHelper.cs

@@ -0,0 +1,67 @@
+using DevExtreme.AspNet.Data.ResponseModel;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using Xunit;
+
+namespace DevExtreme.AspNet.Data.Tests {
+
+    public class RemoteGroupCountTestHelper {
+
+        public interface IEntity {
+            int G1 { get; set; }
+            int G2 { get; set; }
+        }
+
+        public static IEnumerable<T> GenerateTestData<T>(Func<T> itemFactory) where T : IEntity {
+            T CreateItem(int g1, int g2) {
+                var item = itemFactory();
+                item.G1 = g1;
+                item.G2 = g2;
+                return item;
+            }
+            yield return CreateItem(1, 0);
+            yield return CreateItem(2, 1);
+            yield return CreateItem(2, 1);
+            yield return CreateItem(2, 2);
+            yield return CreateItem(3, 0);
+        }
+
+        public static void Run<T>(IQueryable<T> data) {
+            Run(data, new[] {
+                new GroupingInfo { Selector = "G1", IsExpanded = false }
+            });
+            Run(data, new[] {
+                new GroupingInfo { Selector = "G1", IsExpanded = false },
+                new GroupingInfo { Selector = "G2", IsExpanded = false }
+            });
+        }
+
+        static void Run<T>(IQueryable<T> data, GroupingInfo[] group) {
+            var loadOptions = new SampleLoadOptions {
+                RemoteGrouping = true,
+                RequireTotalCount = false,
+                RequireGroupCount = true,
+                Group = group,
+                Skip = 1,
+                Take = 1
+            };
+
+            var loadResult = DataSourceLoader.Load(data, loadOptions);
+            Assert.Equal(3, loadResult.groupCount);
+
+            var log = loadOptions.ExpressionLog;
+
+            if(group.Length == 1) {
+                Assert.Equal(-1, loadResult.totalCount); // not requested
+                Assert.Equal(2, log.Count);
+                Assert.Contains(log, line => line.Contains(".Distinct().Count()"));
+            } else {
+                Assert.Equal(data.Count(), loadResult.totalCount); // bonus because all groups are loaded
+                Assert.Single(log);
+            }
+        }
+    }
+
+}

net/DevExtreme.AspNet.Data.Tests.EF6/DevExtreme.AspNet.Data.Tests.EF6.csproj

@@ -87,6 +87,7 @@
     <Compile Include="Bug239.cs" />
     <Compile Include="Bug240.cs" />
     <Compile Include="ExpandLinqSumType.cs" />
+    <Compile Include="RemoteGroupCount.cs" />
     <Compile Include="PaginateViaPrimaryKey.cs" />
     <Compile Include="RemoteGroupingStress.cs" />
     <Compile Include="Summary.cs" />

net/DevExtreme.AspNet.Data.Tests.EF6/RemoteGroupCount.cs

@@ -0,0 +1,30 @@
+using System;
+using System.Threading.Tasks;
+using Xunit;
+
+namespace DevExtreme.AspNet.Data.Tests.EF6 {
+    using DataItem = RemoteGroupCount_DataItem;
+
+    public class RemoteGroupCount_DataItem : RemoteGroupCountTestHelper.IEntity {
+        public int ID { get; set; }
+        public int G1 { get; set; }
+        public int G2 { get; set; }
+    }
+
+    public class RemoteGroupCount {
+
+        [Fact]
+        public async Task Scenario() {
+            await TestDbContext.ExecAsync(context => {
+                var dbSet = context.Set<DataItem>();
+
+                dbSet.AddRange(RemoteGroupCountTestHelper.GenerateTestData(() => new DataItem()));
+                context.SaveChanges();
+
+                RemoteGroupCountTestHelper.Run(dbSet);
+            });
+        }
+
+    }
+
+}

net/DevExtreme.AspNet.Data.Tests.EF6/TestDbContext.cs

@@ -34,6 +34,7 @@ protected override void OnModelCreating(DbModelBuilder modelBuilder) {
             modelBuilder.Entity<PaginateViaPrimaryKey_DataItem>().HasKey(i => new { i.K1, i.K2 });
             modelBuilder.Entity<Async_DataItem>();
             modelBuilder.Entity<ExpandLinqSumType_DataItem>();
+            modelBuilder.Entity<RemoteGroupCount_DataItem>();
         }
 
         public static async Task ExecAsync(Func<TestDbContext, Task> action) {

net/DevExtreme.AspNet.Data.Tests.EFCore/RemoteGroupCount.cs

@@ -0,0 +1,33 @@
+#if !EFCORE1
+using System;
+using System.ComponentModel.DataAnnotations.Schema;
+using System.Threading.Tasks;
+using Xunit;
+
+namespace DevExtreme.AspNet.Data.Tests.EFCore {
+
+    public class RemoteGroupCount {
+
+        [Table(nameof(RemoteGroupCount) + "_" + nameof(DataItem))]
+        public class DataItem : RemoteGroupCountTestHelper.IEntity {
+            public int ID { get; set; }
+            public int G1 { get; set; }
+            public int G2 { get; set; }
+        }
+
+        [Fact]
+        public async Task Scenario() {
+            await TestDbContext.ExecAsync(context => {
+                var dbSet = context.Set<DataItem>();
+
+                dbSet.AddRange(RemoteGroupCountTestHelper.GenerateTestData(() => new DataItem()));
+                context.SaveChanges();
+
+                RemoteGroupCountTestHelper.Run(dbSet);
+            });
+        }
+
+    }
+
+}
+#endif

net/DevExtreme.AspNet.Data.Tests.EFCore/TestDbContext.cs

@@ -16,6 +16,7 @@ protected override void OnModelCreating(ModelBuilder modelBuilder) {
             modelBuilder.Entity<RemoteGrouping.DataItem>();
 #if !EFCORE1
             modelBuilder.Entity<RemoteGroupingStress.DataItem>();
+            modelBuilder.Entity<RemoteGroupCount.DataItem>();
 #endif
             modelBuilder.Entity<Summary.DataItem>();
             modelBuilder.Entity<Bug120.DataItem>();

net/DevExtreme.AspNet.Data.Tests.L2S/DevExtreme.AspNet.Data.Tests.L2S.csproj

@@ -87,6 +87,7 @@
   </ItemGroup>
   <ItemGroup>
     <Compile Include="AssemblyInfo.cs" />
+    <Compile Include="RemoteGroupCount.cs" />
     <Compile Include="RemoteGroupingStress.cs" />
     <Compile Include="Summary.cs" />
     <Compile Include="T670222_TotalSummary.cs" />

net/DevExtreme.AspNet.Data.Tests.L2S/RemoteGroupCount.cs

@@ -0,0 +1,25 @@
+using System;
+using System.Threading.Tasks;
+using Xunit;
+
+namespace DevExtreme.AspNet.Data.Tests.L2S {
+    using DataItem = RemoteGroupCount_DataItem;
+
+    public class RemoteGroupCount {
+
+        [Fact]
+        public void Scenario() {
+            TestDataContext.Exec(context => {
+                var table = context.RemoteGroupCount_DataItems;
+
+                foreach(var i in RemoteGroupCountTestHelper.GenerateTestData(() => new DataItem()))
+                    table.InsertOnSubmit(i);
+                context.SubmitChanges();
+
+                RemoteGroupCountTestHelper.Run(table);
+            });
+        }
+
+    }
+
+}

net/DevExtreme.AspNet.Data.Tests.L2S/TestDataClasses.cs

@@ -23,6 +23,14 @@ public static void Exec(Action<TestDataContext> action) {
                     )"
                 );
 
+                INSTANCE.ExecuteCommand(
+                    $@"create table {nameof(RemoteGroupCount_DataItem)} (
+                        {nameof(RemoteGroupCount_DataItem.ID)} int identity primary key,
+                        {nameof(RemoteGroupCount_DataItem.G1)} int not null,
+                        {nameof(RemoteGroupCount_DataItem.G2)} int not null
+                    )"
+                );
+
                 INSTANCE.ExecuteCommand(
                     $@"create table {nameof(Summary_DataItem)} (
                         {nameof(Summary_DataItem.ID)} int identity primary key,
@@ -51,6 +59,9 @@ public void PurgeGenericTestTable() {
     partial class RemoteGroupingStress_DataItem : RemoteGroupingStressHelper.IEntity {
     }
 
+    partial class RemoteGroupCount_DataItem : RemoteGroupCountTestHelper.IEntity {
+    }
+
     partial class Summary_DataItem : SummaryTestHelper.IEntity {
     }
 

net/DevExtreme.AspNet.Data.Tests.L2S/TestDataClasses.dbml

@@ -8,6 +8,13 @@
       <Column Name="NullDate" Type="System.DateTime" DbType="datetime2" CanBeNull="true" />
     </Type>
   </Table>
+  <Table Name="" Member="RemoteGroupCount_DataItems">
+    <Type Name="RemoteGroupCount_DataItem">
+      <Column Name="ID" AutoSync="Never" Type="System.Int32" IsPrimaryKey="true" IsDbGenerated="true" CanBeNull="false" />
+      <Column Name="G1" Type="System.Int32" CanBeNull="false" />
+      <Column Name="G2" Type="System.Int32" CanBeNull="false" />
+    </Type>
+  </Table>
   <Table Name="" Member="Summary_DataItems">
     <Type Name="Summary_DataItem">
       <Column Name="ID" AutoSync="Never" Type="System.Int32" IsPrimaryKey="true" IsDbGenerated="true" CanBeNull="false" />