feature/specification-pattern (#94)

Implemented the Specification pattern.

Directory.Build.props

@@ -8,8 +8,8 @@
         <NeutralLanguage>en</NeutralLanguage>
         <Copyright>Copyright © ONIXLabs 2020</Copyright>
         <RepositoryUrl>https://github.com/onix-labs/onixlabs-dotnet</RepositoryUrl>
-        <Version>11.2.0</Version>
-        <PackageVersion>11.2.0</PackageVersion>
-        <AssemblyVersion>11.2.0</AssemblyVersion>
+        <Version>11.3.0</Version>
+        <PackageVersion>11.3.0</PackageVersion>
+        <AssemblyVersion>11.3.0</AssemblyVersion>
     </PropertyGroup>
 </Project>

OnixLabs.Core.UnitTests.Data/Location.cs

@@ -0,0 +1,24 @@
+// Copyright 2020 ONIXLabs
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+namespace OnixLabs.Core.UnitTests.Data;
+
+public sealed record Location(string City, string Country)
+{
+    public static readonly Location London = new("London", "England");
+    public static readonly Location Paris = new("Paris", "France");
+    public static readonly Location Lisbon = new("Lisbon", "Postugal");
+    public static readonly Location Berlin = new("Berlin", "Germany");
+    public static readonly Location Brussels = new("Brussels", "Belgium");
+}

OnixLabs.Core.UnitTests.Data/Person.cs

@@ -0,0 +1,26 @@
+// Copyright 2020 ONIXLabs
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+using System.Collections.Generic;
+
+namespace OnixLabs.Core.UnitTests.Data;
+
+public sealed record Person(string Name, int Age, IEnumerable<Location> Locations)
+{
+    public static readonly Person Alice = new("Alice", 12, [Location.London, Location.Paris]);
+    public static readonly Person Bob = new("Bob", 23, [Location.Lisbon, Location.London]);
+    public static readonly Person Charlie = new("Charlie", 34, [Location.Berlin, Location.Brussels]);
+
+    public static readonly IEnumerable<Person> People = [Alice, Bob, Charlie];
+}

OnixLabs.Core.UnitTests.Data/PersonSpecifications.cs

@@ -0,0 +1,37 @@
+// Copyright 2020 ONIXLabs
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+using System;
+using System.Linq;
+using System.Linq.Expressions;
+
+namespace OnixLabs.Core.UnitTests.Data;
+
+public class PersonSpecification(Expression<Func<Person, bool>> expression) :
+    CriteriaSpecification<Person>(expression);
+
+public sealed class PersonNameEqualsSpecification(string name) :
+    PersonSpecification(person => person.Name == name);
+
+public sealed class PersonNameStartsWithSpecification(string name) :
+    PersonSpecification(person => person.Name.StartsWith(name));
+
+public sealed class PersonOlderThanSpecification(int age) :
+    PersonSpecification(person => person.Age > age);
+
+public sealed class PersonHasLocationSpecification(Location location) :
+    PersonSpecification(person => person.Locations.Contains(location));
+
+public sealed class PersonHasLocationCitySpecification(string city) :
+    PersonSpecification(person => person.Locations.Any(location => location.City == city));

OnixLabs.Core.UnitTests/OptionalTests.cs

@@ -336,7 +336,7 @@ public void OptionalNoneGetValueOrDefaultShouldProduceExpectedResult()
 
         // Then
         Assert.Equal(0, actualNumber);
-        Assert.Equal(null, actualText);
+        Assert.Null(actualText);
     }
 
     [Fact(DisplayName = "Optional Some.GetValueOrDefault with default value should produce the expected result.")]

OnixLabs.Core.UnitTests/SpecificationTests.cs

@@ -0,0 +1,175 @@
+// Copyright 2020 ONIXLabs
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+using System.Collections.Generic;
+using System.Linq;
+using OnixLabs.Core.Linq;
+using OnixLabs.Core.UnitTests.Data;
+using Xunit;
+
+namespace OnixLabs.Core.UnitTests;
+
+public sealed class SpecificationTests
+{
+    [Fact(DisplayName = "PersonNameEqualsSpecification should return the expected result")]
+    public void PersonNameEqualsSpecificationShouldReturnExpectedResult()
+    {
+        // Given
+        PersonNameEqualsSpecification specification = new("Alice");
+
+        // When
+        IEnumerable<Person> result = Person.People.Where(specification).ToList();
+
+        // Then
+        Assert.Single(result);
+        Assert.Contains(Person.Alice, result);
+    }
+
+    [Fact(DisplayName = "PersonNameStartsWithSpecification should return the expected result")]
+    public void PersonNameStartsWithSpecificationShouldReturnExpectedResult()
+    {
+        // Given
+        PersonNameStartsWithSpecification specification = new("A");
+
+        // When
+        IEnumerable<Person> result = Person.People.Where(specification).ToList();
+
+        // Then
+        Assert.Single(result);
+        Assert.Contains(Person.Alice, result);
+    }
+
+    [Fact(DisplayName = "PersonOlderThanSpecification should return the expected result")]
+    public void PersonOlderThanSpecificationShouldReturnExpectedResult()
+    {
+        // Given
+        PersonOlderThanSpecification specification = new(20);
+
+        // When
+        IEnumerable<Person> result = Person.People.Where(specification).ToList();
+
+        // Then
+        Assert.Equal(2, IEnumerableExtensions.Count(result));
+        Assert.Contains(Person.Bob, result);
+        Assert.Contains(Person.Charlie, result);
+    }
+
+    [Fact(DisplayName = "PersonHasLocationSpecification should return the expected result")]
+    public void PersonHasLocationSpecificationShouldReturnExpectedResult()
+    {
+        // Given
+        PersonHasLocationSpecification specification = new(Location.London);
+
+        // When
+        IEnumerable<Person> result = Person.People.Where(specification).ToList();
+
+        // Then
+        Assert.Equal(2, IEnumerableExtensions.Count(result));
+        Assert.Contains(Person.Alice, result);
+        Assert.Contains(Person.Bob, result);
+    }
+
+    [Fact(DisplayName = "PersonHasLocationCitySpecification should return the expected result")]
+    public void PersonHasLocationCitySpecificationShouldReturnExpectedResult()
+    {
+        // Given
+        PersonHasLocationCitySpecification specification = new(Location.London.City);
+
+        // When
+        IEnumerable<Person> result = Person.People.Where(specification).ToList();
+
+        // Then
+        Assert.Equal(2, IEnumerableExtensions.Count(result));
+        Assert.Contains(Person.Alice, result);
+        Assert.Contains(Person.Bob, result);
+    }
+
+    [Fact(DisplayName = "PersonSpecification.And should return the expected result")]
+    public void PersonSpecificationAndShouldReturnExpectedResult()
+    {
+        // Given
+        Specification<Person> specification = PersonSpecification.And(
+            new PersonOlderThanSpecification(20),
+            new PersonHasLocationCitySpecification("London")
+        );
+
+        // When
+        IEnumerable<Person> result = Person.People.Where(specification).ToList();
+
+        // Then
+        Assert.Single(result);
+        Assert.Contains(Person.Bob, result);
+    }
+
+    [Fact(DisplayName = "PersonSpecification.And should return true for an empty collection")]
+    public void PersonSpecificationAndShouldReturnTrueForEmptyCollection()
+    {
+        // Given
+        Specification<Person> specification = PersonSpecification.And();
+
+        // When
+        bool result = specification.IsSatisfiedBy(Person.Alice);
+
+        // Then
+        Assert.True(result);
+    }
+
+    [Fact(DisplayName = "PersonSpecification.Or should return the expected result")]
+    public void PersonSpecificationOrShouldReturnExpectedResult()
+    {
+        // Given
+        Specification<Person> specification = PersonSpecification.Or(
+            new PersonNameStartsWithSpecification("A"),
+            new PersonHasLocationCitySpecification("Lisbon")
+        );
+
+        // When
+        IEnumerable<Person> result = Person.People.Where(specification).ToList();
+
+        // Then
+        Assert.Equal(2, result.Count());
+        Assert.Contains(Person.Alice, result);
+        Assert.Contains(Person.Bob, result);
+    }
+
+    [Fact(DisplayName = "PersonSpecification.Or should return false for an empty collection")]
+    public void PersonSpecificationOrShouldReturnFalseForEmptyCollection()
+    {
+        // Given
+        Specification<Person> specification = PersonSpecification.Or();
+
+        // When
+        bool result = specification.IsSatisfiedBy(Person.Alice);
+
+        // Then
+        Assert.False(result);
+    }
+
+    [Fact(DisplayName = "PersonSpecification.Not should return the expected result")]
+    public void PersonSpecificationNotShouldReturnExpectedResult()
+    {
+        // Given
+        Specification<Person> specification = PersonSpecification.Or(
+            new PersonNameStartsWithSpecification("A"),
+            new PersonHasLocationCitySpecification("Lisbon")
+        );
+
+        // When
+        IEnumerable<Person> result = Person.People.WhereNot(specification).ToList();
+
+        // Then
+        Assert.Single(result);
+        Assert.Contains(Person.Charlie, result);
+    }
+}

OnixLabs.Core/Extensions.DateTime.cs

@@ -1,4 +1,4 @@
-// Copyright 2020-2024 ONIXLabs
+// Copyright 2020 ONIXLabs
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.

OnixLabs.Core/IBinaryConvertible.cs

@@ -12,9 +12,11 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+using System;
+
 namespace OnixLabs.Core;
 
 /// <summary>
-/// Defines a type that is convertible to an instance of <see cref="T:Byte[]"/>.
+/// Defines a type that is convertible to a <see cref="ReadOnlySpan{T}"/>, or <see cref="ReadOnlyMemory{T}"/>.
 /// </summary>
 public interface IBinaryConvertible : ISpanBinaryConvertible, IMemoryBinaryConvertible;

OnixLabs.Core/IMemoryBinaryConvertible.cs

@@ -1,4 +1,4 @@
-// Copyright 2020-2024 ONIXLabs
+// Copyright 2020 ONIXLabs
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.