WikiFunctions.WikiDiff.GetDiff C# (CSharp) Method

        public string GetDiff(string leftText, string rightText, int contextLines)
        {
            Result = new StringBuilder(500000);
            LeftLines = leftText.Split(new[] {"\r\n"}, StringSplitOptions.None);
            RightLines = rightText.Split(new[] {"\r\n"}, StringSplitOptions.None);
            ContextLines = contextLines;

            diff = new Diff(LeftLines, RightLines, true, true);
            foreach (Diff.Hunk h in diff)
            {
                if (h.Same)
                {
                    RenderContext(h);
                }
                else
                {
                    RenderDifference(h);
                }
            }
            return Result.ToString();
        }

        public void DiffHTML()
        {
            WikiDiff d = new WikiDiff();

            string diffResult = d.GetDiff(@"A1
            A2", @"A1
            A2", 2);

            Assert.AreEqual(@"", diffResult, "No HTML when no change");

            diffResult = d.GetDiff(@"A1
            A2", @"A1X
            A2", 2).Replace(System.Environment.NewLine, " ");

            diffResult = Regex.Replace(diffResult, @"\s+", " ");

            Assert.AreEqual(@"<tr onclick='window.external.GoTo(0)'> <td colspan='2' class='diff-lineno'>Line 1:</td> <td colspan='2' class='diff-lineno'>Line 1:</td> </tr><tr onclick='window.external.GoTo(0)' ondblclick='window.external.UndoChange(0,0)'> <td>-</td> <td class='diff-deletedline'><span class='diffchange'>A1</span> </td> <td>+</td> <td class='diff-addedline'><span class='diffchange'>A1X</span> </td> </tr><tr onclick='window.external.GoTo(1);'> <td class='diff-marker'> </td> <td class='diff-context'>A2</td> <td class='diff-marker'> </td> <td class='diff-context'>A2</td> </tr>", diffResult, "Standard case: first line changed");

            diffResult = d.GetDiff(@"A1
            A2", @"A1X
            A2X", 2).Replace(System.Environment.NewLine, " ");

            diffResult = Regex.Replace(diffResult, @"\s+", " ");

            Assert.AreEqual(@"<tr onclick='window.external.GoTo(0)'> <td colspan='2' class='diff-lineno'>Line 1:</td> <td colspan='2' class='diff-lineno'>Line 1:</td> </tr><tr onclick='window.external.GoTo(0)' ondblclick='window.external.UndoChange(0,0)'> <td>-</td> <td class='diff-deletedline'><span class='diffchange'>A1</span> </td> <td>+</td> <td class='diff-addedline'><span class='diffchange'>A1X</span> </td> </tr><tr onclick='window.external.GoTo(1)' ondblclick='window.external.UndoChange(1,1)'> <td>-</td> <td class='diff-deletedline'><span class='diffchange'>A2</span> </td> <td>+</td> <td class='diff-addedline'><span class='diffchange'>A2X</span> </td> </tr>", diffResult, "Standard case: two lines changed");

            diffResult = d.GetDiff(@"A1
            A2", @"A1", 2).Replace(System.Environment.NewLine, " ");

            diffResult = Regex.Replace(diffResult, @"\s+", " ");

            Assert.AreEqual(@"<tr onclick='window.external.GoTo(0);'> <td class='diff-marker'> </td> <td class='diff-context'>A1</td> <td class='diff-marker'> </td> <td class='diff-context'>A1</td> </tr><tr> <td>-</td> <td class='diff-deletedline' onclick='window.external.GoTo(1)' ondblclick='window.external.UndoDeletion(1, 1)'>A2 </td> <td> </td> <td> </td> </tr>", diffResult, "Standard case: second line deleted");
        }