Implement an infrastructure for auto discovery of evaluators and validators.

.editorconfig

@@ -108,9 +108,9 @@ dotnet_naming_rule.non_field_members_should_be_pascal_case.severity = suggestion
 dotnet_naming_rule.non_field_members_should_be_pascal_case.symbols = non_field_members
 dotnet_naming_rule.non_field_members_should_be_pascal_case.style = pascal_case
 
-dotnet_naming_rule.private_or_internal_field_should_be__fieldname.severity = suggestion
-dotnet_naming_rule.private_or_internal_field_should_be__fieldname.symbols = private_or_internal_field
-dotnet_naming_rule.private_or_internal_field_should_be__fieldname.style = _fieldname
+dotnet_naming_rule.private_field_should_be__fieldname.severity = suggestion
+dotnet_naming_rule.private_field_should_be__fieldname.symbols = private_field
+dotnet_naming_rule.private_field_should_be__fieldname.style = _fieldname
 
 dotnet_naming_rule.public_field_should_be_pascal_case.severity = suggestion
 dotnet_naming_rule.public_field_should_be_pascal_case.symbols = public_field
@@ -122,6 +122,10 @@ dotnet_naming_symbols.interface.applicable_kinds = interface
 dotnet_naming_symbols.interface.applicable_accessibilities = public, internal, private, protected, protected_internal, private_protected
 dotnet_naming_symbols.interface.required_modifiers = 
 
+dotnet_naming_symbols.private_field.applicable_kinds = field
+dotnet_naming_symbols.private_field.applicable_accessibilities = private, private_protected
+dotnet_naming_symbols.private_field.required_modifiers = 
+
 dotnet_naming_symbols.private_or_internal_field.applicable_kinds = field
 dotnet_naming_symbols.private_or_internal_field.applicable_accessibilities = internal, private, private_protected
 dotnet_naming_symbols.private_or_internal_field.required_modifiers = 

QuerySpecification.sln

@@ -34,6 +34,8 @@ Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "Solution Items", "Solution
 		setup-sqllocaldb.ps1 = setup-sqllocaldb.ps1
 	EndProjectSection
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "QuerySpecification.AutoDiscovery.Tests", "tests\QuerySpecification.AutoDiscovery.Tests\QuerySpecification.AutoDiscovery.Tests.csproj", "{154BA43D-0416-4840-85E1-B5ED34929E04}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -60,6 +62,10 @@ Global
 		{F25DE99A-0BE4-41C6-9D1C-570CCE6B0BB9}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{F25DE99A-0BE4-41C6-9D1C-570CCE6B0BB9}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{F25DE99A-0BE4-41C6-9D1C-570CCE6B0BB9}.Release|Any CPU.Build.0 = Release|Any CPU
+		{154BA43D-0416-4840-85E1-B5ED34929E04}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{154BA43D-0416-4840-85E1-B5ED34929E04}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{154BA43D-0416-4840-85E1-B5ED34929E04}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{154BA43D-0416-4840-85E1-B5ED34929E04}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
@@ -68,6 +74,7 @@ Global
 		{BAFCF13F-05EF-4DEF-AD78-B5006CE86784} = {670F5387-F816-409B-8048-183F2608EDB3}
 		{F85A5DB8-DB84-430A-8DA1-43A613FBD0CC} = {670F5387-F816-409B-8048-183F2608EDB3}
 		{F25DE99A-0BE4-41C6-9D1C-570CCE6B0BB9} = {670F5387-F816-409B-8048-183F2608EDB3}
+		{154BA43D-0416-4840-85E1-B5ED34929E04} = {670F5387-F816-409B-8048-183F2608EDB3}
 	EndGlobalSection
 	GlobalSection(ExtensibilityGlobals) = postSolution
 		SolutionGuid = {E5CD485E-D269-41DE-A144-EEC734F5B893}

exclusion.dic

@@ -23,3 +23,4 @@ aaaab
 aaaaab
 axza
 Compilable
+netstandard

src/Directory.Build.props

@@ -37,6 +37,11 @@
     <PackageIcon>pozitronicon.png</PackageIcon>
   </PropertyGroup>
 
+  <PropertyGroup>
+    <!--Missing XML comment-->
+    <!--<NoWarn>1591</NoWarn>-->
+  </PropertyGroup>
+
   <ItemGroup>
     <None Include="../../pozitronicon.png" Pack="true" PackagePath="\" Visible="false" />
     <None Include="../../readme-nuget.md" Pack="true" PackagePath="\" Visible="false" />

src/QuerySpecification.EntityFrameworkCore/Evaluators/AsNoTrackingEvaluator.cs

@@ -3,6 +3,7 @@
 /// <summary>
 /// Evaluator to apply AsNoTracking to the query if the specification has AsNoTracking set to true.
 /// </summary>
+[EvaluatorDiscovery(Order = 100)]
 public sealed class AsNoTrackingEvaluator : IEvaluator
 {
     /// <summary>

src/QuerySpecification.EntityFrameworkCore/Evaluators/AsNoTrackingWithIdentityResolutionEvaluator.cs

@@ -3,6 +3,7 @@
 /// <summary>
 /// Evaluator to apply AsNoTracking to the query if the specification has AsNoTracking set to true.
 /// </summary>
+[EvaluatorDiscovery(Order = 110)]
 public sealed class AsNoTrackingWithIdentityResolutionEvaluator : IEvaluator
 {
     /// <summary>

src/QuerySpecification.EntityFrameworkCore/Evaluators/AsSplitQueryEvaluator.cs

@@ -3,6 +3,7 @@
 /// <summary>
 /// Evaluator to apply AsSplitQuery to the query if the specification has AsSplitQuery set to true.
 /// </summary>
+[EvaluatorDiscovery(Order = 90)]
 public sealed class AsSplitQueryEvaluator : IEvaluator
 {
     /// <summary>

src/QuerySpecification.EntityFrameworkCore/Evaluators/AsTrackingEvaluator.cs

@@ -3,6 +3,7 @@
 /// <summary>
 /// Evaluator to apply AsTracking to the query if the specification has AsTracking set to true.
 /// </summary>
+[EvaluatorDiscovery(Order = 120)]
 public sealed class AsTrackingEvaluator : IEvaluator
 {
     /// <summary>

src/QuerySpecification.EntityFrameworkCore/Evaluators/IgnoreAutoIncludesEvaluator.cs

@@ -3,6 +3,7 @@
 /// <summary>
 /// Evaluator to apply IgnoreAutoIncludes to the query if the specification has IgnoreAutoIncludes set to true.
 /// </summary>
+[EvaluatorDiscovery(Order = 70)]
 public sealed class IgnoreAutoIncludesEvaluator : IEvaluator
 {
 

src/QuerySpecification.EntityFrameworkCore/Evaluators/IgnoreQueryFiltersEvaluator.cs

@@ -3,6 +3,7 @@
 /// <summary>
 /// Evaluator to apply IgnoreQueryFilters to the query if the specification has IgnoreQueryFilters set to true.
 /// </summary>
+[EvaluatorDiscovery(Order = 80)]
 public sealed class IgnoreQueryFiltersEvaluator : IEvaluator
 {
 

src/QuerySpecification.EntityFrameworkCore/Evaluators/IncludeEvaluator.cs

@@ -1,5 +1,4 @@
 using Microsoft.EntityFrameworkCore.Query;
-using System.Collections;
 using System.Collections.Concurrent;
 using System.Diagnostics;
 using System.Reflection;
@@ -9,6 +8,7 @@ namespace Pozitron.QuerySpecification;
 /// <summary>
 /// Evaluates a specification to include navigation properties.
 /// </summary>
+[EvaluatorDiscovery(Order = 40)]
 public sealed class IncludeEvaluator : IEvaluator
 {
     private static readonly MethodInfo _includeMethodInfo = typeof(EntityFrameworkQueryableExtensions)

src/QuerySpecification.EntityFrameworkCore/Evaluators/IncludeStringEvaluator.cs

@@ -3,6 +3,7 @@
 /// <summary>
 /// Evaluates a specification to include navigation properties specified by string paths.
 /// </summary>
+[EvaluatorDiscovery(Order = 30)]
 public sealed class IncludeStringEvaluator : IEvaluator
 {
 

src/QuerySpecification.EntityFrameworkCore/Evaluators/LikeEvaluator.cs

@@ -19,6 +19,7 @@ This was the previous implementation. We're trying to avoid allocations of LikeE
 /// <summary>
 /// Evaluates a specification to apply "like" expressions for filtering.
 /// </summary>
+[EvaluatorDiscovery(Order = 20)]
 public sealed class LikeEvaluator : IEvaluator
 {
     private LikeEvaluator() { }

src/QuerySpecification.EntityFrameworkCore/Evaluators/QueryTagEvaluator.cs

@@ -3,6 +3,7 @@
 /// <summary>
 /// Evaluator to apply the query tags to the query.
 /// </summary>
+[EvaluatorDiscovery(Order = 60)]
 public sealed class QueryTagEvaluator : IEvaluator
 {
 

src/QuerySpecification.EntityFrameworkCore/Evaluators/SpecificationEvaluator.cs

@@ -20,21 +20,23 @@ public class SpecificationEvaluator
     /// </summary>
     public SpecificationEvaluator()
     {
-        Evaluators =
-        [
-            WhereEvaluator.Instance,
-            LikeEvaluator.Instance,
-            IncludeStringEvaluator.Instance,
-            IncludeEvaluator.Instance,
-            OrderEvaluator.Instance,
-            IgnoreQueryFiltersEvaluator.Instance,
-            AsNoTrackingEvaluator.Instance,
-            AsNoTrackingWithIdentityResolutionEvaluator.Instance,
-            AsTrackingEvaluator.Instance,
-            AsSplitQueryEvaluator.Instance,
-            IgnoreAutoIncludesEvaluator.Instance,
-            QueryTagEvaluator.Instance,
-        ];
+        Evaluators = TypeDiscovery.IsAutoDiscoveryEnabled
+            ? TypeDiscovery.GetEvaluators()
+            :
+            [
+                WhereEvaluator.Instance,
+                LikeEvaluator.Instance,
+                IncludeStringEvaluator.Instance,
+                IncludeEvaluator.Instance,
+                OrderEvaluator.Instance,
+                QueryTagEvaluator.Instance,
+                IgnoreAutoIncludesEvaluator.Instance,
+                IgnoreQueryFiltersEvaluator.Instance,
+                AsSplitQueryEvaluator.Instance,
+                AsNoTrackingEvaluator.Instance,
+                AsNoTrackingWithIdentityResolutionEvaluator.Instance,
+                AsTrackingEvaluator.Instance,
+            ];
     }
 
     /// <summary>

src/QuerySpecification/DiscoveryAttribute.cs

@@ -0,0 +1,40 @@
+namespace Pozitron.QuerySpecification;
+
+/// <summary>
+/// Specifies whether auto discovery for evaluators and validators is enabled.
+/// </summary>
+[AttributeUsage(AttributeTargets.Assembly)]
+public sealed class SpecAutoDiscoveryAttribute : Attribute
+{
+}
+
+/// <summary>
+/// Specifies discovery options for evaluators and validators, such as the order and whether discovery is enabled.
+/// </summary>
+[AttributeUsage(AttributeTargets.Class, Inherited = false, AllowMultiple = false)]
+public class DiscoveryAttribute : Attribute
+{
+    /// <summary>
+    /// Gets the order in which the evaluator/validator should be applied. Lower values are applied first.
+    /// </summary>
+    public int Order { get; set; } = int.MaxValue;
+
+    /// <summary>
+    /// Gets a value indicating whether the evaluator/validator is discoverable.
+    /// </summary>
+    public bool Enable { get; set; } = true;
+}
+
+/// <summary>
+/// Specifies discovery options for evaluators, such as the order and whether discovery is enabled.
+/// </summary>
+public sealed class EvaluatorDiscoveryAttribute : DiscoveryAttribute
+{
+}
+
+/// <summary>
+/// Specifies discovery options for validators, such as the order and whether discovery is enabled.
+/// </summary>
+public sealed class ValidatorDiscoveryAttribute : DiscoveryAttribute
+{
+}

src/QuerySpecification/Evaluators/IInMemoryEvaluator.cs → src/QuerySpecification/Evaluators/IMemoryEvaluator.cs

@@ -3,7 +3,7 @@
 /// <summary>
 /// Represents an in-memory evaluator that processes a specification.
 /// </summary>
-public interface IInMemoryEvaluator
+public interface IMemoryEvaluator
 {
     /// <summary>
     /// Evaluates the given specification on the provided enumerable source.

src/QuerySpecification/Evaluators/LikeMemoryEvaluator.cs

@@ -14,13 +14,14 @@ public IEnumerable<T> Evaluate<T>(IEnumerable<T> source, Specification<T> specif
     This was the previous implementation. We're trying to avoid allocations of LikeExpressions, GroupBy and LINQ.
     The new implementation preserves the behavior and reduces allocations drastically.
     We've implemented a custom iterator. Also, instead of GroupBy, we have a single array sorted by group, and we slice it to get the groups.
-    For source of 1000 items, the allocations are reduced from 257.872 bytes to only 64 bytes (the cost of the iterator instance). Refer to LikeInMemoryEvaluatorBenchmark results.
+    For source of 1000 items, the allocations are reduced from 257.872 bytes to only 64 bytes (the cost of the iterator instance). Refer to LikeMemoryEvaluatorBenchmark results.
  */
 
 /// <summary>
 /// Represents an in-memory evaluator for "Like" expressions.
 /// </summary>
-public sealed class LikeMemoryEvaluator : IInMemoryEvaluator
+[EvaluatorDiscovery(Order = 20)]
+public sealed class LikeMemoryEvaluator : IMemoryEvaluator
 {
     /// <summary>
     /// Gets the singleton instance of the <see cref="LikeMemoryEvaluator"/> class.

src/QuerySpecification/Evaluators/OrderEvaluator.cs

@@ -3,7 +3,8 @@
 /// <summary>
 /// Represents an evaluator for order expressions.
 /// </summary>
-public sealed class OrderEvaluator : IEvaluator, IInMemoryEvaluator
+[EvaluatorDiscovery(Order = 50)]
+public sealed class OrderEvaluator : IEvaluator, IMemoryEvaluator
 {
     /// <summary>
     /// Gets the singleton instance of the <see cref="OrderEvaluator"/> class.

src/QuerySpecification/Evaluators/SpecificationInMemoryEvaluator.cs → src/QuerySpecification/Evaluators/SpecificationMemoryEvaluator.cs

@@ -3,36 +3,38 @@
 /// <summary>
 /// Evaluates specifications in memory.
 /// </summary>
-public class SpecificationInMemoryEvaluator
+public class SpecificationMemoryEvaluator
 {
     /// <summary>
-    /// Gets the default instance of the <see cref="SpecificationInMemoryEvaluator"/> class.
+    /// Gets the default instance of the <see cref="SpecificationMemoryEvaluator"/> class.
     /// </summary>
-    public static SpecificationInMemoryEvaluator Default = new();
+    public static SpecificationMemoryEvaluator Default = new();
 
     /// <summary>
     /// Gets the list of in-memory evaluators.
     /// </summary>
-    protected List<IInMemoryEvaluator> Evaluators { get; }
+    protected List<IMemoryEvaluator> Evaluators { get; }
 
     /// <summary>
-    /// Initializes a new instance of the <see cref="SpecificationInMemoryEvaluator"/> class.
+    /// Initializes a new instance of the <see cref="SpecificationMemoryEvaluator"/> class.
     /// </summary>
-    public SpecificationInMemoryEvaluator()
+    public SpecificationMemoryEvaluator()
     {
-        Evaluators =
-        [
-            WhereEvaluator.Instance,
-            OrderEvaluator.Instance,
-            LikeMemoryEvaluator.Instance,
-        ];
+        Evaluators = TypeDiscovery.IsAutoDiscoveryEnabled
+            ? TypeDiscovery.GetMemoryEvaluators()
+            :
+            [
+                WhereEvaluator.Instance,
+                LikeMemoryEvaluator.Instance,
+                OrderEvaluator.Instance,
+            ];
     }
 
     /// <summary>
-    /// Initializes a new instance of the <see cref="SpecificationInMemoryEvaluator"/> class with the specified evaluators.
+    /// Initializes a new instance of the <see cref="SpecificationMemoryEvaluator"/> class with the specified evaluators.
     /// </summary>
     /// <param name="evaluators">The in-memory evaluators to use.</param>
-    public SpecificationInMemoryEvaluator(IEnumerable<IInMemoryEvaluator> evaluators)
+    public SpecificationMemoryEvaluator(IEnumerable<IMemoryEvaluator> evaluators)
     {
         Evaluators = evaluators.ToList();
     }

src/QuerySpecification/Evaluators/WhereEvaluator.cs

@@ -3,7 +3,8 @@
 /// <summary>
 /// Represents an evaluator for where expressions.
 /// </summary>
-public sealed class WhereEvaluator : IEvaluator, IInMemoryEvaluator
+[EvaluatorDiscovery(Order = 10)]
+public sealed class WhereEvaluator : IEvaluator, IMemoryEvaluator
 {
     /// <summary>
     /// Gets the singleton instance of the <see cref="WhereEvaluator"/> class.