Add Equals and HashCode to StringEnum

Author: jingming

src/Twilio/Types/StringEnum.cs

@@ -1,4 +1,6 @@
-namespace Twilio.Types
+using System;
+
+namespace Twilio.Types
 {
     /// <summary>
     /// Enum object for strings
@@ -38,6 +40,27 @@ public override string ToString()
         {
             return _value;
         }
+
+        public override int GetHashCode()
+        {
+            return _value.GetHashCode();
+        }
+
+        public override bool Equals(object obj)
+        {
+            if (obj == null || !obj.GetType().Equals(GetType()))
+            {
+                return false;
+            }
+
+            var o = (StringEnum) Convert.ChangeType(obj, GetType());
+            if (o == null)
+            {
+                return false;
+            }
+
+            return o._value.Equals(_value);
+        }
     }
 }
 

test/Twilio.Test/Types/StringEnumTest.cs

@@ -0,0 +1,53 @@
+using System;
+using NUnit.Framework;
+using Twilio.Types;
+
+namespace Twilio.Tests.Types
+{
+    [TestFixture]
+    public class StringEnumTest
+    {
+        public sealed class Enum1 : StringEnum
+        {
+            private Enum1(string value) : base(value) { }
+            public Enum1() { }
+
+            public static readonly Enum1 V1 = new Enum1("v1");
+            public static readonly Enum1 V2 = new Enum1("v2");
+        }
+
+        public sealed class Enum2 : StringEnum
+        {
+            private Enum2(string value) : base(value) { }
+            public Enum2() { }
+
+            public static readonly Enum2 V1 = new Enum2("v1");
+            public static readonly Enum2 V2 = new Enum2("v2");
+        }
+
+        [Test]
+        public void TestEnumComparison()
+        {
+            Assert.AreNotEqual(Enum1.V1, Enum1.V2);
+            Assert.AreNotEqual(Enum2.V2, Enum1.V2);
+            Assert.AreEqual(Enum1.V1, Enum1.V1);
+        }
+
+        public class Instance
+        {
+            public Enum1 E1 { get; set; }
+        }
+
+        [Test]
+        public void TestInstance()
+        {
+            var i = new Instance
+            {
+                E1 = Enum1.V1
+            };
+
+            Assert.AreNotEqual(i.E1, Enum2.V1);
+            Assert.AreEqual(i.E1, Enum1.V1);
+        }
+    }
+}