Add AsTracking feature. (#338)

* Added AsTracking feature.

* Accounted for tracking order.

* Added tests.

Specification.EntityFrameworkCore/src/Ardalis.Specification.EntityFrameworkCore/Evaluators/AsTrackingEvaluator.cs

@@ -0,0 +1,26 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using Microsoft.EntityFrameworkCore;
+
+namespace Ardalis.Specification.EntityFrameworkCore
+{
+  public class AsTrackingEvaluator : IEvaluator
+  {
+    private AsTrackingEvaluator() { }
+    public static AsTrackingEvaluator Instance { get; } = new AsTrackingEvaluator();
+
+    public bool IsCriteriaEvaluator { get; } = true;
+
+    public IQueryable<T> GetQuery<T>(IQueryable<T> query, ISpecification<T> specification) where T : class
+    {
+      if (specification.AsTracking)
+      {
+        query = query.AsTracking();
+      }
+
+      return query;
+    }
+  }
+}

Specification.EntityFrameworkCore/src/Ardalis.Specification.EntityFrameworkCore/Evaluators/SpecificationEvaluator.cs

@@ -30,11 +30,10 @@ public SpecificationEvaluator(bool cacheEnabled = false)
                 OrderEvaluator.Instance,
                 PaginationEvaluator.Instance,
                 AsNoTrackingEvaluator.Instance,
+                AsNoTrackingWithIdentityResolutionEvaluator.Instance,
+                AsTrackingEvaluator.Instance,
                 IgnoreQueryFiltersEvaluator.Instance,
-#if !NETSTANDARD2_0
-                AsSplitQueryEvaluator.Instance,
-                AsNoTrackingWithIdentityResolutionEvaluator.Instance
-#endif
+                AsSplitQueryEvaluator.Instance
       });
     }
 

Specification/src/Ardalis.Specification/Builder/SpecificationBuilderExtensions.cs

@@ -370,6 +370,35 @@ public static ICacheSpecificationBuilder<T> EnableCache<T>(
       return cacheBuilder;
     }
 
+    /// <summary>
+    /// If the entity instances are modified, this will be detected
+    /// by the change tracker.
+    /// </summary>
+    /// <param name="specificationBuilder"></param>
+    public static ISpecificationBuilder<T> AsTracking<T>(
+        this ISpecificationBuilder<T> specificationBuilder) where T : class
+        => AsTracking(specificationBuilder, true);
+
+    /// <summary>
+    /// If the entity instances are modified, this will be detected
+    /// by the change tracker.
+    /// </summary>
+    /// <param name="specificationBuilder"></param>
+    /// <param name="condition">If false, the setting will be discarded.</param>
+    public static ISpecificationBuilder<T> AsTracking<T>(
+        this ISpecificationBuilder<T> specificationBuilder,
+        bool condition) where T : class
+    {
+      if (condition)
+      {
+        specificationBuilder.Specification.AsNoTracking = false;
+        specificationBuilder.Specification.AsNoTrackingWithIdentityResolution = false;
+        specificationBuilder.Specification.AsTracking = true;
+      }
+
+      return specificationBuilder;
+    }
+
     /// <summary>
     /// If the entity instances are modified, this will not be detected
     /// by the change tracker.
@@ -391,6 +420,8 @@ public static ISpecificationBuilder<T> AsNoTracking<T>(
     {
       if (condition)
       {
+        specificationBuilder.Specification.AsTracking = false;
+        specificationBuilder.Specification.AsNoTrackingWithIdentityResolution = false;
         specificationBuilder.Specification.AsNoTracking = true;
       }
 
@@ -463,6 +494,8 @@ public static ISpecificationBuilder<T> AsNoTrackingWithIdentityResolution<T>(
     {
       if (condition)
       {
+        specificationBuilder.Specification.AsTracking = false;
+        specificationBuilder.Specification.AsNoTracking = false;
         specificationBuilder.Specification.AsNoTrackingWithIdentityResolution = true;
       }
 

Specification/src/Ardalis.Specification/ISpecification.cs

@@ -97,6 +97,12 @@ public interface ISpecification<T>
     /// </summary>
     string? CacheKey { get; }
 
+    /// <summary>
+    /// Returns whether or not the change tracker will track any of the entities
+    /// that are returned.
+    /// </summary>
+    bool AsTracking { get; }
+
     /// <summary>
     /// Returns whether or not the change tracker will track any of the entities
     /// that are returned. When true, if the entity instances are modified, this will not be detected

Specification/src/Ardalis.Specification/Specification.cs

@@ -108,6 +108,9 @@ public virtual bool IsSatisfiedBy(T entity)
     /// <inheritdoc/>
     public bool CacheEnabled { get; internal set; }
 
+    /// <inheritdoc/>
+    public bool AsTracking { get; internal set; } = false;
+
     /// <inheritdoc/>
     public bool AsNoTracking { get; internal set; } = false;
 

Specification/tests/Ardalis.Specification.UnitTests/BuilderTests/SpecificationBuilderExtensions_AsNoTracking.cs

@@ -29,5 +29,13 @@ public void FlagsAsNoTracking_GivenSpecWithAsNoTracking()
 
       spec.AsNoTracking.Should().Be(true);
     }
+
+    [Fact]
+    public void FlagsAsNoTracking_GivenSpecWithAsTrackingAndEndWithAsNoTracking()
+    {
+      var spec = new CompanyByIdWithAsTrackingAsUntrackedSpec(1);
+
+      spec.AsNoTracking.Should().Be(true);
+    }
   }
 }

Specification/tests/Ardalis.Specification.UnitTests/BuilderTests/SpecificationBuilderExtensions_AsNoTrackingWithIdentityResolution.cs

@@ -29,5 +29,13 @@ public void FlagsAsNoTracking_GivenSpecWithAsNoTrackingWithIdentityResolution()
 
       spec.AsNoTrackingWithIdentityResolution.Should().Be(true);
     }
+
+    [Fact]
+    public void FlagsAsNoTracking_GivenSpecWithAsTrackingAndEndWithAsNoTrackingWithIdentityResolution()
+    {
+      var spec = new CompanyByIdWithAsTrackingAsUntrackedWithIdentityResolutionSpec(1);
+
+      spec.AsNoTrackingWithIdentityResolution.Should().Be(true);
+    }
   }
 }

Specification/tests/Ardalis.Specification.UnitTests/BuilderTests/SpecificationBuilderExtensions_AsTracking.cs

@@ -0,0 +1,41 @@
+using Ardalis.Specification.UnitTests.Fixture.Specs;
+using FluentAssertions;
+using Xunit;
+
+namespace Ardalis.Specification.UnitTests.BuilderTests
+{
+  public class SpecificationBuilderExtensions_AsTracking
+  {
+    [Fact]
+    public void DoesNothing_GivenSpecWithoutAsTracking()
+    {
+      var spec = new StoreEmptySpec();
+
+      spec.AsTracking.Should().Be(false);
+    }
+
+    [Fact]
+    public void DoesNothing_GivenAsTrackingWithFalseCondition()
+    {
+      var spec = new CompanyByIdWithFalseConditions(1);
+
+      spec.AsTracking.Should().Be(false);
+    }
+
+    [Fact]
+    public void FlagsAsTracking_GivenSpecWithAsTracking()
+    {
+      var spec = new CompanyByIdAsTrackedSpec(1);
+
+      spec.AsTracking.Should().Be(true);
+    }
+
+    [Fact]
+    public void FlagsAsTracking_GivenSpecWithAsNoTrackingAndEndWithAsTracking()
+    {
+      var spec = new CompanyByIdWithAsNoTrackingAsTrackedSpec(1);
+
+      spec.AsTracking.Should().Be(true);
+    }
+  }
+}

Specification/tests/Ardalis.Specification.UnitTests/Fixture/Specs/CompanyByIdAsTrackedSpec.cs

@@ -0,0 +1,12 @@
+using Ardalis.Specification.UnitTests.Fixture.Entities;
+
+namespace Ardalis.Specification.UnitTests.Fixture.Specs
+{
+  public class CompanyByIdAsTrackedSpec : Specification<Company>, ISingleResultSpecification<Company>
+  {
+    public CompanyByIdAsTrackedSpec(int id)
+    {
+      Query.Where(company => company.Id == id).AsTracking();
+    }
+  }
+}

Specification/tests/Ardalis.Specification.UnitTests/Fixture/Specs/CompanyByIdWithAsNoTrackingAsTrackedSpec.cs

@@ -0,0 +1,12 @@
+using Ardalis.Specification.UnitTests.Fixture.Entities;
+
+namespace Ardalis.Specification.UnitTests.Fixture.Specs
+{
+  public class CompanyByIdWithAsNoTrackingAsTrackedSpec : Specification<Company>, ISingleResultSpecification<Company>
+  {
+    public CompanyByIdWithAsNoTrackingAsTrackedSpec(int id)
+    {
+      Query.Where(company => company.Id == id).AsNoTracking().AsNoTrackingWithIdentityResolution().AsTracking();
+    }
+  }
+}

Specification/tests/Ardalis.Specification.UnitTests/Fixture/Specs/CompanyByIdWithAsTrackingAsUntrackedSpec.cs

@@ -0,0 +1,12 @@
+using Ardalis.Specification.UnitTests.Fixture.Entities;
+
+namespace Ardalis.Specification.UnitTests.Fixture.Specs
+{
+  public class CompanyByIdWithAsTrackingAsUntrackedSpec : Specification<Company>, ISingleResultSpecification<Company>
+  {
+    public CompanyByIdWithAsTrackingAsUntrackedSpec(int id)
+    {
+      Query.Where(company => company.Id == id).AsTracking().AsNoTracking();
+    }
+  }
+}

Specification/tests/Ardalis.Specification.UnitTests/Fixture/Specs/CompanyByIdWithAsTrackingAsUntrackedWithIdentityResolutionSpec.cs

@@ -0,0 +1,13 @@
+using Ardalis.Specification.UnitTests.Fixture.Entities;
+
+namespace Ardalis.Specification.UnitTests.Fixture.Specs
+{
+  public class CompanyByIdWithAsTrackingAsUntrackedWithIdentityResolutionSpec : Specification<Company>,
+    ISingleResultSpecification<Company>
+  {
+    public CompanyByIdWithAsTrackingAsUntrackedWithIdentityResolutionSpec(int id)
+    {
+      Query.Where(company => company.Id == id).AsTracking().AsNoTrackingWithIdentityResolution();
+    }
+  }
+}