fix(RelationshipAttribute): correct Equals and ToString

Author: jfhs

src/JsonApiDotNetCore/Models/RelationshipAttribute.cs

@@ -16,5 +16,20 @@ protected RelationshipAttribute(string publicName)
         public bool IsHasOne { get { return this.GetType() == typeof(HasOneAttribute); } }
 
         public abstract void SetValue(object entity, object newValue);
+
+        public override string ToString()
+        {
+            return base.ToString() + ":" + PublicRelationshipName;
+        }
+
+        public override bool Equals(object obj)
+        {
+            RelationshipAttribute attr = obj as RelationshipAttribute;
+            if (attr == null)
+            {
+                return false;
+            }
+            return IsHasMany == attr.IsHasMany && PublicRelationshipName.Equals(attr.PublicRelationshipName);
+        }
     }
 }

test/JsonApiDotNetCoreExampleTests/Unit/Models/AttributesEqualsTests.cs

@@ -0,0 +1,75 @@
+using JsonApiDotNetCore.Models;
+using System;
+using System.Collections.Generic;
+using System.Text;
+using Xunit;
+
+namespace JsonApiDotNetCoreExampleTests.Unit.Models
+{
+    public class AttributesEqualsTests
+    {
+        [Fact]
+        public void HasManyAttribute_Equals_Returns_True_When_Same_Name()
+        {
+            var a = new HasManyAttribute("test");
+            var b = new HasManyAttribute("test");
+
+            Assert.Equal(a, b);
+        }
+
+        [Fact]
+        public void HasManyAttribute_Equals_Returns_False_When_Different_Name()
+        {
+            var a = new HasManyAttribute("test");
+            var b = new HasManyAttribute("test2");
+
+            Assert.NotEqual(a, b);
+        }
+
+        [Fact]
+        public void HasOneAttribute_Equals_Returns_True_When_Same_Name()
+        {
+            var a = new HasOneAttribute("test");
+            var b = new HasOneAttribute("test");
+
+            Assert.Equal(a, b);
+        }
+
+        [Fact]
+        public void HasOneAttribute_Equals_Returns_False_When_Different_Name()
+        {
+            var a = new HasOneAttribute("test");
+            var b = new HasOneAttribute("test2");
+
+            Assert.NotEqual(a, b);
+        }
+
+        [Fact]
+        public void AttrAttribute_Equals_Returns_True_When_Same_Name()
+        {
+            var a = new AttrAttribute("test");
+            var b = new AttrAttribute("test");
+
+            Assert.Equal(a, b);
+        }
+
+        [Fact]
+        public void AttrAttribute_Equals_Returns_False_When_Different_Name()
+        {
+            var a = new AttrAttribute("test");
+            var b = new AttrAttribute("test2");
+
+            Assert.NotEqual(a, b);
+        }
+
+        [Fact]
+        public void HasManyAttribute_Doesnt_Equal_HasOneAttribute_With_Same_Name()
+        {
+            RelationshipAttribute a = new HasManyAttribute("test");
+            RelationshipAttribute b = new HasOneAttribute("test");
+
+            Assert.NotEqual(a, b);
+            Assert.NotEqual(b, a);
+        }
+    }
+}