Added value semantics to Oid

MongoDB.Net-Tests/TestOid.cs

@@ -46,7 +46,34 @@ public class TestOid
         [Test]
         public void TestOidEquality(){
             Oid val = new Oid("4a7067c30a57000000008ecb");
-            Assert.AreEqual(val, new Oid(val.ToString().Replace("\"", "")));
+            Oid other = new Oid("4a7067c30a57000000008ecb");
+
+            Assert.IsTrue(val.Equals(other), "Equals(Oid) did not work");
+            Assert.IsTrue(val == other, "== operator did not work");
+        }
+
+        [Test]
+        public void TestOidInEquality(){
+            Oid val = new Oid("4a7067c30a57000000008ecb");
+            Oid other = new Oid("5a7067c30a57000000008ecb");
+
+            Assert.IsFalse(val == null);
+            Assert.IsFalse(val == other);
+            Assert.IsFalse(val.Equals(other));
+            Assert.IsTrue(val != null);
+            Assert.IsTrue(val != other);
+        }
+
+        [Test]
+        public void TestOidComparisons(){
+            Oid lower = new Oid("4a7067c30a57000000008ecb");
+            Oid higher = new Oid("5a7067c30a57000000008ecb");
+
+            Assert.AreEqual(1, lower.CompareTo(null));
+            Assert.AreEqual(1, higher.CompareTo(lower));
+
+            Assert.IsTrue(lower < higher);
+            Assert.IsTrue(higher > lower);
         }
 
         [Test]
@@ -110,8 +137,19 @@ public class TestOid
             //Expected: 2010-01-07 02:24:56.633
             DateTime expected = new DateTime(2010,1,7,7,21,57,DateTimeKind.Utc);
             Assert.AreEqual(expected,oid.Created);
-
-
         }
+
+        [Test]
+        public void TestToByteArray(){
+            byte[] bytes = new byte[]{1,2,3,4,5,6,7,8,9,10,11,12};
+            string hex = "0102030405060708090a0b0c";
+
+            Oid bval = new Oid(bytes);
+            byte[] bytes2 = bval.ToByteArray();
+
+            Assert.IsNotNull(bytes2);
+            Assert.AreEqual(12, bytes2.Length);
+            Assert.AreEqual(bytes, bytes2);
+        }        
     }
 }

MongoDBDriver/Oid.cs

@@ -7,7 +7,7 @@ namespace MongoDB.Driver{
     /// <summary>
     /// Oid is an immutable object that represents a Mongo ObjectId.
     /// </summary>
-    public class Oid
+    public class Oid: IEquatable<Oid>, IComparable<Oid>
     {
         private static OidGenerator oidGenerator = new OidGenerator();
 
@@ -27,11 +27,6 @@ public class Oid
             }
         }
 
-        /// <summary>
-        /// Initializes a new instance of the <see cref="Oid"/> class.
-        /// </summary>
-        public Oid(){}
-
         /// <summary>
         /// Initializes a new instance of the <see cref="Oid"/> class.
         /// </summary>
@@ -50,24 +45,40 @@ public class Oid
             Array.Copy(value,bytes,12);
         }
 
+
         /// <summary>
         /// Determines whether the specified <see cref="System.Object"/> is equal to this instance.
         /// </summary>
         /// <param name="obj">The <see cref="System.Object"/> to compare with this instance.</param>
         /// <returns>
         /// 	<c>true</c> if the specified <see cref="System.Object"/> is equal to this instance; otherwise, <c>false</c>.
         /// </returns>
-        /// <exception cref="T:System.NullReferenceException">
-        /// The <paramref name="obj"/> parameter is null.
-        /// </exception>
         public override bool Equals(object obj){
-            if(obj.GetType() == typeof(Oid)){
-                string hex = obj.ToString();
-                return this.ToString().Equals(hex);
+            if(obj is Oid){
+                return this.CompareTo((Oid)obj) == 0;
             }
             return false;
         }
 
+        public bool Equals (Oid other){
+            return this.CompareTo(other) == 0;
+        }
+
+        public int CompareTo (Oid other){
+            if (System.Object.ReferenceEquals(other, null)){
+                return 1;
+            }
+            byte[] otherBytes = other.ToByteArray();
+            for(int x = 0; x < bytes.Length; x++){
+                if(bytes[x] < otherBytes[x]){
+                    return -1;
+                }else if(bytes[x] > otherBytes[x]){
+                    return 1;
+                }
+            }
+            return 0;
+        }
+
         /// <summary>
         /// Returns a hash code for this instance.
         /// </summary>
@@ -106,6 +117,23 @@ public class Oid
         public static Oid Generate(){
             return oidGenerator.Generate();   
         }
+
+        public static bool operator ==(Oid a, Oid b){
+            return a.Equals(b);
+        }
+
+        public static bool operator !=(Oid a, Oid b){
+            return !(a == b);
+        }
+
+        public static bool operator >(Oid a, Oid b){
+            return a.CompareTo(b) > 0;
+        }
+
+        public static bool operator <(Oid a, Oid b){
+            return a.CompareTo(b) < 0;
+        }
+
 
         /// <summary>
         /// Validates the hex.