public static void WriteUnifiedDiff(string[] leftLines, string leftName, string[] rightLines, string rightName,
TextWriter writer, int context, bool caseSensitive,
bool compareWhitespace)
{
Diff diff = new Diff(leftLines, rightLines, caseSensitive, compareWhitespace);
WriteUnifiedDiff(diff, writer, leftName, rightName, context);
}
private void RenderDifference(Diff.Hunk hunk)
{
Range left = hunk.Left;
Range right = hunk.Right;
if (right.Start == 0) ContextHeader(0, 0);
int changes = Math.Min(left.Count, right.Count);
for (int i = 0; i < changes; i++)
{
LineChanged(left.Start + i, right.Start + i);
}
if (left.Count > right.Count)
{
for (int i = changes; i < left.Count; i++)
{
LineDeleted(left.Start + i, right.Start + changes);
}
}
else if (left.Count < right.Count)
{
for (int i = changes; i < right.Count; i++)
{
LineAdded(right.Start + i);
}
}
}
/// <summary>
/// Renders diff
/// </summary>
/// <param name="leftText">Earlier version of the text</param>
/// <param name="rightText">Later version of the text</param>
/// <param name="contextLines">Number of unchanged lines to show around changed ones</param>
/// <returns>HTML diff</returns>
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 static void WriteUnifiedDiff(Diff diff, TextWriter writer, string fromfile, string tofile, int context)
{
writer.Write("--- ");
writer.WriteLine(fromfile);
writer.Write("+++ ");
writer.WriteLine(tofile);
ArrayList hunkset = new ArrayList();
foreach (Diff.Hunk hunk in diff) {
Diff.Hunk lasthunk = null;
if (hunkset.Count > 0) lasthunk = (Diff.Hunk)hunkset[hunkset.Count-1];
if (hunk.Same) {
// At the start of a hunk set, keep only context lines of context.
if (lasthunk == null) {
if (hunk.Left.Count > context)
hunkset.Add( hunk.Crop(hunk.Left.Count-context, 0) );
else
hunkset.Add( hunk );
// Can't have two same hunks in a row, so the last one was a difference.
} else {
// Small enough context that this unified diff range will not stop.
if (hunk.Left.Count <= context*2) {
hunkset.Add( hunk );
// Too much of the same. Keep context lines and end this section.
// And then keep the last context lines as context for the next section.
} else {
hunkset.Add( hunk.Crop(0, hunk.Left.Count-context) );
WriteUnifiedDiffSection(writer, hunkset);
hunkset.Clear();
if (hunk.Left.Count > context)
hunkset.Add( hunk.Crop(hunk.Left.Count-context, 0) );
else
hunkset.Add( hunk );
}
}
} else {
hunkset.Add(hunk);
}
}
if (hunkset.Count > 0 && !(hunkset.Count == 1 && ((Diff.Hunk)hunkset[0]).Same))
WriteUnifiedDiffSection(writer, hunkset);
}
private void RenderContext(Diff.Hunk hunk)
{
Range left = hunk.Left;
Range right = hunk.Right;
int displayed = 0;
if (Result.Length > 0) // not the first hunk, adding context for previous change
{
displayed = Math.Min(ContextLines, right.Count);
for (int i = 0; i < displayed; i++) ContextLine(right.Start + i);
}
int toDisplay = Math.Min(right.Count - displayed, ContextLines);
if ((left.End < LeftLines.Length - 1 || right.End < RightLines.Length - 1) && toDisplay > 0)
// not the last hunk, adding context for next change
{
if (right.Count > displayed + toDisplay) ContextHeader(left.End - toDisplay + 1, right.End - toDisplay + 1);
for (int i = 0; i < toDisplay; i++) ContextLine(right.End - toDisplay + i + 1);
}
}
private void LineChanged(int leftLine, int rightLine)
{
// some kind of glitch with the diff engine
if (LeftLines[leftLine] == RightLines[rightLine])
{
ContextLine(rightLine);
return;
}
StringBuilder left = new StringBuilder();
StringBuilder right = new StringBuilder();
List<Word> leftList = Word.SplitString(LeftLines[leftLine]);
List<Word> rightList = Word.SplitString(RightLines[rightLine]);
diff = new Diff(leftList, rightList, Word.Comparer);
foreach (Diff.Hunk h in diff)
{
if (h.Same)
{
for (int i = 0; i < h.Left.Count; i++)
{
WhitespaceDiff(left, rightList[h.Right.Start + i], leftList[h.Left.Start + i]);
WhitespaceDiff(right, leftList[h.Left.Start + i], rightList[h.Right.Start + i]);
}
}
else
{
WordDiff(left, h.Left, h.Right, leftList, rightList);
WordDiff(right, h.Right, h.Left, rightList, leftList);
}
}
Result.AppendFormat(@"<tr onclick='window.external.GoTo({1})' ondblclick='window.external.UndoChange({0},{1})'>
<td>-</td>
<td class='diff-deletedline'>", leftLine, rightLine);
Result.Append(left);
Result.Append(@" </td>
<td>+</td>
<td class='diff-addedline'>");
Result.Append(right);
Result.Append(@" </td>
</tr>");
}
private static void WhitespaceDiff(StringBuilder res, Word left, Word right)
{
if (left.Whitespace == right.Whitespace) res.Append(HttpUtility.HtmlEncode(right.ToString()));
else
{
res.Append(HttpUtility.HtmlEncode(right.TheWord));
char[] leftChars = left.Whitespace.ToCharArray();
char[] rightChars = right.Whitespace.ToCharArray();
Diff diff = new Diff(leftChars, rightChars, Word.Comparer);
foreach (Diff.Hunk h in diff)
{
if (h.Same)
res.Append(rightChars, h.Right.Start, h.Right.Count);
else
{
res.Append("<span class='diffchange'>");
res.Append('\x00A0', h.Right.Count); // replace spaces with NBSPs to make 'em visible
res.Append("</span>");
}
}
}
}
public static void WriteUnifiedDiff(Diff diff, TextWriter writer)
{
WriteUnifiedDiff(diff, writer, "Left", "Right", 2);
}
public Enumerator(Diff diff)
{
this.diff = diff;
Reset();
}
private void LineChanged(int leftLine, int rightLine)
{
// some kind of glitch with the diff engine
if (LeftLines[leftLine] == RightLines[rightLine])
{
ContextLine(rightLine);
return;
}
StringBuilder left = new StringBuilder();
StringBuilder right = new StringBuilder();
List <Word> leftList = Word.SplitString(LeftLines[leftLine]);
List <Word> rightList = Word.SplitString(RightLines[rightLine]);
diff = new Diff(leftList, rightList, Word.Comparer);
foreach (Diff.Hunk h in diff)
{
if (h.Same)
{
for (int i = 0; i < h.Left.Count; i++)
{
WhitespaceDiff(left, rightList[h.Right.Start + i], leftList[h.Left.Start + i]);
WhitespaceDiff(right, leftList[h.Left.Start + i], rightList[h.Right.Start + i]);
}
}
else
{
WordDiff(left, h.Left, h.Right, leftList, rightList);
WordDiff(right, h.Right, h.Left, rightList, leftList);
}
}
if (!Variables.RTL)
{
Result.AppendFormat(@"<tr onclick='window.external.GoTo({1})' ondblclick='window.external.UndoChange({0},{1})'>
<td>+</td>
<td class='diff-addedline'>", rightLine, leftLine);
Result.Append(right);
Result.Append(@" </td>
<td>-</td>
<td class='diff-deletedline'>");
Result.Append(left);
Result.Append(@" </td>
</tr>");
}
else
{
Result.AppendFormat(@"<tr onclick='window.external.GoTo({1})' ondblclick='window.external.UndoChange({0},{1})'>
<td>-</td>
<td class='diff-deletedline'>", leftLine, rightLine);
Result.Append(left);
Result.Append(@" </td>
<td>+</td>
<td class='diff-addedline'>");
Result.Append(right);
Result.Append(@" </td>
</tr>");
}
}
public static void WriteUnifiedDiff(Diff diff, TextWriter writer, string fromfile, string tofile, int context)
{
writer.Write("--- ");
writer.WriteLine(fromfile);
writer.Write("+++ ");
writer.WriteLine(tofile);
ArrayList hunkset = new ArrayList();
foreach (Diff.Hunk hunk in diff)
{
Diff.Hunk lasthunk = null;
if (hunkset.Count > 0)
{
lasthunk = (Diff.Hunk)hunkset[hunkset.Count - 1];
}
if (hunk.Same)
{
// At the start of a hunk set, keep only context lines of context.
if (lasthunk == null)
{
if (hunk.Left.Count > context)
{
hunkset.Add(hunk.Crop(hunk.Left.Count - context, 0));
}
else
{
hunkset.Add(hunk);
}
// Can't have two same hunks in a row, so the last one was a difference.
}
else
{
// Small enough context that this unified diff range will not stop.
if (hunk.Left.Count <= context * 2)
{
hunkset.Add(hunk);
// Too much of the same. Keep context lines and end this section.
// And then keep the last context lines as context for the next section.
}
else
{
hunkset.Add(hunk.Crop(0, hunk.Left.Count - context));
WriteUnifiedDiffSection(writer, hunkset);
hunkset.Clear();
if (hunk.Left.Count > context)
{
hunkset.Add(hunk.Crop(hunk.Left.Count - context, 0));
}
else
{
hunkset.Add(hunk);
}
}
}
}
else
{
hunkset.Add(hunk);
}
}
if (hunkset.Count > 0 && !(hunkset.Count == 1 && ((Diff.Hunk)hunkset[0]).Same))
{
WriteUnifiedDiffSection(writer, hunkset);
}
}
public static void WriteUnifiedDiff(Diff diff, TextWriter writer)
{
WriteUnifiedDiff(diff, writer, "Left", "Right", 2);
}
public static void WriteUnifiedDiff(string[] leftLines, string leftName, string[] rightLines, string rightName, System.IO.TextWriter writer, int context, bool caseSensitive, bool compareWhitespace)
{
Diff diff = new Diff(leftLines, rightLines, caseSensitive, compareWhitespace);
WriteUnifiedDiff(diff, writer, leftName, rightName, context);
}