Add comparison methods to mapping classes.

This involved adding Equals and == methods to LineMapping.cs and MappingLocation.cs.

src/Microsoft.AspNet.Razor/Generator/Compiler/LineMappings/LineMapping.cs

@@ -3,7 +3,40 @@ namespace Microsoft.AspNet.Razor.Generator.Compiler
 {
     public class LineMapping
     {
+        public LineMapping()
+            : this(documentLocation: null, generatedLocation: null)
+        {
+        }
+
+        public LineMapping(MappingLocation documentLocation, MappingLocation generatedLocation)
+        {
+            DocumentLocation = documentLocation;
+            GeneratedLocation = generatedLocation;
+        }
+
         public MappingLocation DocumentLocation { get; set; }
         public MappingLocation GeneratedLocation { get; set; }
+
+        public override bool Equals(object obj)
+        {
+            LineMapping other = obj as LineMapping;
+            return DocumentLocation.Equals(other.DocumentLocation) &&
+                   GeneratedLocation.Equals(other.GeneratedLocation);
+        }
+
+        public override int GetHashCode()
+        {
+            return base.GetHashCode();
+        }
+
+        public static bool operator ==(LineMapping left, LineMapping right)
+        {
+            return left.Equals(right);
+        }
+
+        public static bool operator !=(LineMapping left, LineMapping right)
+        {
+            return !left.Equals(right);
+        }
     }
 }

src/Microsoft.AspNet.Razor/Generator/Compiler/LineMappings/MappingLocation.cs

@@ -18,5 +18,30 @@ namespace Microsoft.AspNet.Razor.Generator.Compiler
         public int AbsoluteIndex { get; set; }
         public int LineIndex { get; set; }
         public int CharacterIndex { get; set; }
+
+        public override bool Equals(object obj)
+        {
+            MappingLocation other = obj as MappingLocation;
+
+            return AbsoluteIndex == other.AbsoluteIndex &&
+                   ContentLength == other.ContentLength &&
+                   LineIndex == other.LineIndex &&
+                   CharacterIndex == other.CharacterIndex;
+        }
+
+        public override int GetHashCode()
+        {
+            return base.GetHashCode();
+        }
+
+        public static bool operator ==(MappingLocation left, MappingLocation right)
+        {
+            return left.Equals(right);
+        }
+
+        public static bool operator !=(MappingLocation left, MappingLocation right)
+        {
+            return !left.Equals(right);
+        }
     }
 }