Adicionado propriedade para ignorar delete ou não marcar o insert.

HtmlDiff/Diff.cs

@@ -16,8 +16,7 @@ public class HtmlDiff
 
         private readonly StringBuilder _content;
         private string _newText;
-        private string _oldText;
-
+        private string _oldText;               
 
         private static Dictionary<string, int> _specialCaseClosingTags = new Dictionary<string, int>(StringComparer.OrdinalIgnoreCase)
         {
@@ -84,6 +83,16 @@ public class HtmlDiff
         /// </summary>
         public double OrphanMatchThreshold { get; set; }
 
+        /// <summary>
+        /// If true all deleted texts are not formatted.
+        /// </summary>
+        public bool IgnoreDelete { get; set; }
+
+        /// <summary>
+        /// If true all inserted texts are not formatted.
+        /// </summary>
+        public bool IgnoreInsert { get; set; }
+
         /// <summary>
         ///     Initializes a new instance of the class.
         /// </summary>
@@ -188,11 +197,21 @@ private void ProcessReplaceOperation(Operation operation)
         private void ProcessInsertOperation(Operation operation, string cssClass)
         {
             List<string> text = _newWords.Where((s, pos) => pos >= operation.StartInNew && pos < operation.EndInNew).ToList();
+
+            if (IgnoreInsert)
+            {
+                _content.Append(string.Join("", text.ToArray()));
+                return;
+            }
+
             InsertTag("ins", cssClass, text);
         }
 
         private void ProcessDeleteOperation(Operation operation, string cssClass)
         {
+            if (IgnoreDelete)
+                return;
+
             List<string> text = _oldWords.Where((s, pos) => pos >= operation.StartInOld && pos < operation.EndInOld).ToList();
             InsertTag("del", cssClass, text);
         }

HtmlDiff/HtmlDiff.csproj

@@ -36,6 +36,12 @@
     <ErrorReport>prompt</ErrorReport>
     <WarningLevel>4</WarningLevel>
   </PropertyGroup>
+  <PropertyGroup>
+    <SignAssembly>true</SignAssembly>
+  </PropertyGroup>
+  <PropertyGroup>
+    <AssemblyOriginatorKeyFile>HtmlDiffPublicPrivate.snk</AssemblyOriginatorKeyFile>
+  </PropertyGroup>
   <ItemGroup>
     <Reference Include="System" />
     <Reference Include="System.Core">
@@ -66,6 +72,7 @@
     <None Include="HtmlDiff.nuspec">
       <SubType>Designer</SubType>
     </None>
+    <None Include="HtmlDiffPublicPrivate.snk" />
   </ItemGroup>
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
   <!-- To modify your build process, add your task inside one of the targets below and uncomment it. 

HtmlDiff/Properties/AssemblyInfo.cs

@@ -32,5 +32,5 @@
 // You can specify all the values or you can default the Build and Revision Numbers 
 // by using the '*' as shown below:
 // [assembly: AssemblyVersion("1.0.*")]
-[assembly: AssemblyVersion("1.3")]
-[assembly: AssemblyFileVersion("1.3")]
+[assembly: AssemblyVersion("1.3.1")]
+[assembly: AssemblyFileVersion("1.3.1")]

Test.HtmlDiff/HtmlDiffSpecTests.cs

@@ -117,5 +117,71 @@ public void Execute_WithGroupCandididatesAndDuplicateGroupsConfigured_ArgumentEx
             var ex = Assert.Throws<ArgumentException>(() => diff.Build());
             Assert.IsTrue(ex.Message.EndsWith(pattern));
         }
+
+
+        #region NewOptions
+
+        [TestCase(
+            "one a word is somewhere", 
+            "a word is somewhere",
+            "a word is somewhere")]
+
+        [TestCase(
+            "one a word is somewhere", 
+            "two a word is somewhere",
+            "<ins class='diffmod'>two</ins> a word is somewhere")]
+        public void Execute_WithIgnoreDelete_OutputVerified(string oldText, string newText, string delta)
+        {
+            Debug.WriteLine("Old text: " + oldText);
+            Debug.WriteLine("New text: " + newText);
+            Debug.WriteLine("");
+            Debug.WriteLine("Expected Diff: " + delta);
+            var diff = new global::HtmlDiff.HtmlDiff(oldText, newText){ IgnoreDelete = true};
+            var result = diff.Build();
+            Debug.WriteLine("");
+            Debug.WriteLine("Actual Diff: " + result);
+            Assert.AreEqual(delta, result);
+        }
+
+        [TestCase(
+            "a word is somewhere", 
+            "one a word is somewhere",
+            "one a word is somewhere")]
+
+        [TestCase(
+            "one a word is somewhere", 
+            "two a word is somewhere",
+            "<del class='diffmod'>one</del>two a word is somewhere")]
+        public void Execute_WithIgnoreInsert_OutputVerified(string oldText, string newText, string delta)
+        {
+            Debug.WriteLine("Old text: " + oldText);
+            Debug.WriteLine("New text: " + newText);
+            Debug.WriteLine("");
+            Debug.WriteLine("Expected Diff: " + delta);
+            var diff = new global::HtmlDiff.HtmlDiff(oldText, newText){ IgnoreInsert = true };
+            var result = diff.Build();
+            Debug.WriteLine("");
+            Debug.WriteLine("Actual Diff: " + result);
+            Assert.AreEqual(delta, result);
+        }
+
+        [TestCase(
+            "one a word is somewhere", 
+            "two a texts is somewhere",
+            "two a texts is somewhere")]
+        public void Execute_WithIgnoreDeleteAndIgnoreInsert_OutputVerified(string oldText, string newText, string delta)
+        {
+            Debug.WriteLine("Old text: " + oldText);
+            Debug.WriteLine("New text: " + newText);
+            Debug.WriteLine("");
+            Debug.WriteLine("Expected Diff: " + delta);
+            var diff = new global::HtmlDiff.HtmlDiff(oldText, newText){ IgnoreDelete = true, IgnoreInsert = true };
+            var result = diff.Build();
+            Debug.WriteLine("");
+            Debug.WriteLine("Actual Diff: " + result);
+            Assert.AreEqual(delta, result);
+        }
+
+        #endregion
     }
 }