Added PagedResult extensions. (#17)

src/QuerySpecification.EntityFrameworkCore/Extensions/IQueryableExtensions.cs

@@ -21,4 +21,30 @@ public static IQueryable<TResult> WithSpecification<TSource, TResult>(
         evaluator ??= SpecificationEvaluator.Default;
         return evaluator.GetQuery(source, specification);
     }
+
+    public static Task<PagedResult<TSource>> ToPagedResultAsync<TSource>(
+      this IQueryable<TSource> source,
+      PagingFilter filter,
+      CancellationToken cancellationToken = default)
+      where TSource : class
+        => ToPagedResultAsync(source, filter, PaginationSettings.Default, cancellationToken);
+
+    public static async Task<PagedResult<TSource>> ToPagedResultAsync<TSource>(
+      this IQueryable<TSource> source,
+      PagingFilter filter,
+      PaginationSettings paginationSettings,
+      CancellationToken cancellationToken = default)
+      where TSource : class
+    {
+        var count = await source.CountAsync(cancellationToken);
+        var pagination = new Pagination(paginationSettings, count, filter);
+
+        var query = source
+            .Skip(pagination.Skip)
+            .Take(pagination.Take);
+
+        var data = await query.ToListAsync(cancellationToken);
+
+        return new PagedResult<TSource>(data, pagination);
+    }
 }

tests/QuerySpecification.EntityFrameworkCore.Tests/Extensions/LikeExtensionTests.cs → tests/QuerySpecification.EntityFrameworkCore.Tests/Extensions/Extensions_Like.cs

@@ -1,10 +1,10 @@
 namespace Tests.Extensions;
 
 [Collection("SharedCollection")]
-public class LikeExtensionTests(TestFactory factory) : IntegrationTest(factory)
+public class Extensions_Like(TestFactory factory) : IntegrationTest(factory)
 {
     [Fact]
-    public void Like_GivenSpecWithMultipleLike()
+    public void QueriesMatch_GivenSpecWithMultipleLike()
     {
         var storeTerm = "ab";
         var companyTerm = "ab";
@@ -28,7 +28,7 @@ public void Like_GivenSpecWithMultipleLike()
     }
 
     [Fact]
-    public void Like_GivenEmptySpec()
+    public void QueriesMatch_GivenEmptySpec()
     {
         var spec = new Specification<Store>();
 

tests/QuerySpecification.EntityFrameworkCore.Tests/Extensions/Extensions_ToPagedResult.cs

@@ -0,0 +1,106 @@
+namespace Tests.Extensions;
+
+[Collection("SharedCollection")]
+public class Extensions_ToPagedResult(TestFactory factory) : IntegrationTest(factory)
+{
+    [Fact]
+    public async Task ReturnsPaginatedItems_GivenPagingFilter()
+    {
+        var expected = new List<Country>
+        {
+            new() { No = 4, Name = "b" },
+        };
+        await SeedRangeAsync<Country>(
+        [
+            new() { No = 9, Name = "a" },
+            new() { No = 9, Name = "c" },
+            new() { No = 1, Name = "b" },
+            new() { No = 2, Name = "b" },
+            new() { No = 3, Name = "b" },
+            new() { No = 4, Name = "b" },
+            new() { No = 9, Name = "d" },
+        ]);
+
+        var filter = new PagingFilter() { Page = 2, PageSize = 3 };
+
+        var result = await DbContext.Countries
+            .Where(x => x.Name == "b")
+            .OrderBy(x => x.No)
+            .ToPagedResultAsync(filter);
+
+        result.Should().BeOfType<PagedResult<Country>>();
+        result.Pagination.Page.Should().Be(filter.Page);
+        result.Pagination.PageSize.Should().Be(filter.PageSize);
+        result.Data.Should().HaveCount(1);
+        result.Data.First().No.Should().Be(4);
+    }
+
+    [Fact]
+    public async Task ReturnsPaginatedItems_GivenPagingFilterAndPaginationSettings()
+    {
+        var expected = new List<Country>
+        {
+            new() { No = 3, Name = "b" },
+            new() { No = 4, Name = "b" },
+        };
+        await SeedRangeAsync<Country>(
+        [
+            new() { No = 9, Name = "a" },
+            new() { No = 9, Name = "c" },
+            new() { No = 1, Name = "b" },
+            new() { No = 2, Name = "b" },
+            new() { No = 3, Name = "b" },
+            new() { No = 4, Name = "b" },
+            new() { No = 9, Name = "d" },
+        ]);
+
+        var paginationSettings = new PaginationSettings(2, 2);
+        var filter = new PagingFilter() { Page = 2, PageSize = 3 };
+
+        var result = await DbContext.Countries
+            .Where(x => x.Name == "b")
+            .OrderBy(x => x.No)
+            .ToPagedResultAsync(filter, paginationSettings);
+
+        result.Should().BeOfType<PagedResult<Country>>();
+        result.Pagination.Page.Should().Be(filter.Page);
+        result.Pagination.PageSize.Should().Be(paginationSettings.DefaultPageSize);
+        result.Data.Should().HaveCount(2);
+        result.Data.First().No.Should().Be(3);
+    }
+
+    [Fact]
+    public async Task ReturnsPaginatedItemsWithAggregatedTakeSkip_GivenPagingFilterAndTakeSkip()
+    {
+        var expected = new List<Country>
+        {
+            new() { No = 2, Name = "b" },
+            new() { No = 3, Name = "b" },
+        };
+        await SeedRangeAsync<Country>(
+        [
+            new() { No = 9, Name = "a" },
+            new() { No = 9, Name = "c" },
+            new() { No = 1, Name = "b" },
+            new() { No = 2, Name = "b" },
+            new() { No = 3, Name = "b" },
+            new() { No = 4, Name = "b" },
+            new() { No = 9, Name = "d" },
+        ]);
+
+        var filter = new PagingFilter() { Page = 2, PageSize = 3 };
+
+        var result = await DbContext.Countries
+            .Where(x => x.Name == "b")
+            .OrderBy(x => x.No)
+            .Skip(1)
+            .Take(2)
+            .ToPagedResultAsync(filter);
+
+        result.Should().BeOfType<PagedResult<Country>>();
+        result.Pagination.Page.Should().Be(PaginationSettings.Default.DefaultPage);
+        result.Pagination.PageSize.Should().Be(filter.PageSize);
+        result.Data.Should().HaveCount(2);
+        result.Data.First().No.Should().Be(2);
+    }
+}

tests/QuerySpecification.EntityFrameworkCore.Tests/Extensions/DbSetExtensionsTests.cs → tests/QuerySpecification.EntityFrameworkCore.Tests/Extensions/Extensions_WithSpecification.cs

@@ -1,13 +1,12 @@
 namespace Tests.Extensions;
 
 [Collection("SharedCollection")]
-public class DbSetExtensionsTests(TestFactory factory) : IntegrationTest(factory)
+public class Extensions_WithSpecification(TestFactory factory) : IntegrationTest(factory)
 {
     public record CountryDto(string? Name);
-    public record ProductImageDto(string? ImageUrl);
 
     [Fact]
-    public void WithSpecification_GivenFullQuery()
+    public void QueriesMatch_GivenFullQuery()
     {
         var id = 1;
         var name = "Store1";
@@ -60,7 +59,7 @@ public void WithSpecification_GivenFullQuery()
     }
 
     [Fact]
-    public void WithSpecification_GivenFullQueryWithSelect()
+    public void QueriesMatch_GivenFullQueryWithSelect()
     {
         var id = 1;
         var name = "Store1";
@@ -115,7 +114,7 @@ public void WithSpecification_GivenFullQueryWithSelect()
     }
 
     [Fact]
-    public void WithSpecification_GivenFullQueryWithSelectMany()
+    public void QueriesMatch_GivenFullQueryWithSelectMany()
     {
         var id = 1;
         var name = "Store1";
@@ -170,7 +169,7 @@ public void WithSpecification_GivenFullQueryWithSelectMany()
     }
 
     [Fact]
-    public void WithSpecification_GivenCustomEvaluator()
+    public void QueriesMatch_GivenCustomEvaluator()
     {
         var id = 1;
 
@@ -192,7 +191,7 @@ public void WithSpecification_GivenCustomEvaluator()
     }
 
     [Fact]
-    public void WithSpecification_GivenSelectorAndCustomEvaluator()
+    public void QueriesMatch_GivenSelectorAndCustomEvaluator()
     {
         var id = 1;
 

tests/QuerySpecification.EntityFrameworkCore.Tests/Repositories/Repository_AnyTests.cs

@@ -137,6 +137,10 @@ await SeedRangeAsync(
         var result = await repo.AnyAsync(spec);
 
         result.Should().BeTrue();
+
+        // Ensure that the spec's pagination is not altered.
+        spec.Skip.Should().Be(3);
+        spec.Take.Should().Be(1);
     }
 
     [Fact]
@@ -169,5 +173,9 @@ await SeedRangeAsync<Country>(
         var result = await repo.AnyAsync(spec);
 
         result.Should().BeTrue();
+
+        // Ensure that the spec's pagination is not altered.
+        spec.Skip.Should().Be(3);
+        spec.Take.Should().Be(1);
     }
 }

tests/QuerySpecification.EntityFrameworkCore.Tests/Repositories/Repository_CountTests.cs

@@ -137,6 +137,10 @@ await SeedRangeAsync(
         var result = await repo.CountAsync(spec);
 
         result.Should().Be(expected.Count);
+
+        // Ensure that the spec's pagination is not altered.
+        spec.Skip.Should().Be(1);
+        spec.Take.Should().Be(1);
     }
 
     [Fact]
@@ -169,5 +173,9 @@ await SeedRangeAsync<Country>(
         var result = await repo.CountAsync(spec);
 
         result.Should().Be(expected.Count);
+
+        // Ensure that the spec's pagination is not altered.
+        spec.Skip.Should().Be(1);
+        spec.Take.Should().Be(1);
     }
 }

tests/QuerySpecification.EntityFrameworkCore.Tests/Repositories/Repository_ProjectToTests.cs

@@ -150,9 +150,6 @@ public async Task ProjectToListAsync_ReturnsPaginatedItems_GivenSpecAndPagingFil
     {
         var expected = new List<CountryDto>
         {
-            new(1, "b"),
-            new(2, "b"),
-            new(3, "b"),
             new(4, "b"),
         };
         await SeedRangeAsync<Country>(
@@ -187,9 +184,6 @@ public async Task ProjectToListAsync_IgnoresSpecPagination_GivenSpecAndPagingFil
     {
         var expected = new List<CountryDto>
         {
-            new(1, "b"),
-            new(2, "b"),
-            new(3, "b"),
             new(4, "b"),
         };
         await SeedRangeAsync<Country>(