/// <summary>
/// Finds all the common elements in all the loaded collections and returns a list. Might want to override if the
/// diff produces diff elements of a different type
/// </summary>
/// <returns>The collection of common elements</returns>
public virtual IDiffObjectsCollection FindCommonElements()
{
int n = _collections.Count;
IDiffObjectsCollection commonElements = _collections[0];
for (int i = 1; i < n; i++)
{
//disable merges for this diff
bool allowMerges = _properties.AllowMerges;
_properties.AllowMerges = false;
DoDiff(commonElements, _collections[i]);
_properties.AllowMerges = allowMerges;
//replace the current collection with the common elements collection
//at the next iteration the next element in the collection will be compared against the common elements
commonElements = _collections[i].CommonElements;
if (commonElements.Count == 0)
{
return(commonElements); //return an empty collection, there are no common elements
}
//sort the elements by position
commonElements.SortByPosition();
}
return(commonElements); //the last element will hold all the common elements
}
public void PushRange(IDiffObjectsCollection collection)
{
if (collection != null)
{
Items.InsertRange(0, collection.Items);
}
}
/// <summary>
/// Executes the diff operation between the specified indexes of the collections list
/// </summary>
/// <param name="indexOfFirst">The index of the first element to diff</param>
/// <param name="indexOfSecond">The index of the second element to diff</param>
public double DoDiff(int indexOfFirst, int indexOfSecond)
{
IDiffObjectsCollection first = _collections[indexOfFirst];
IDiffObjectsCollection second = _collections[indexOfSecond];
return(DoDiff(first, second));
}
/// <summary>
/// Check if the values match and outputs a set of granular differences
/// </summary>
/// <param name="diffObject"></param>
/// <param name="diffsForSelf"></param>
/// <param name="diffsForArgument"></param>
/// <returns></returns>
public bool ValueMatches(IDiffObject diffObject,
out IDiffObjectsCollection diffsForSelf,
out IDiffObjectsCollection diffsForArgument,
out IDiffObjectsCollection commonElements)
{
HeaderDiffObject otherObject = diffObject as HeaderDiffObject;
diffsForSelf = null;
diffsForArgument = null;
commonElements = null;
bool matches = false;
if (otherObject != null)
{
matches = _headerLineHash == otherObject.HeaderLineHash;
//if the values are different but the headers are the same
if (!matches && String.Compare(_name, otherObject.Name, true) == 0)
{
WordsDiffer valuesDiffer = new WordsDiffer();
valuesDiffer.AddTask(_values);
valuesDiffer.AddTask(otherObject.Values);
valuesDiffer.Properties.Sorted = true;
valuesDiffer.Properties.CaseInSensitiveSort = true;
double diffRatio = valuesDiffer.DoDiff(0, 1);
diffsForSelf = valuesDiffer.GetResultingDifferences(0);
diffsForArgument = valuesDiffer.GetResultingDifferences(1);
commonElements = valuesDiffer.GetResultingCommonElements(0);
matches = diffRatio >= _valuesMinSimilarity;
}
}
return(matches);
}
public void WordsDiff()
{
string text1 = "first second;third1";
string text2 = "second;first fourth-third";
WordsDiffer differ = new WordsDiffer();
DiffResult result = differ.DoDiff(text1, text2);
IDiffObjectsCollection firstDiffs = result.DifferencesForFirst;
IDiffObjectsCollection secondDiffs = result.DifferencesForSecond;
Assert.IsTrue(firstDiffs[0].ValueEquals(new WordDiffObject(0, 0, "first ")));
Assert.IsTrue(firstDiffs[1].ValueEquals(new LetterDiffObject(0, 0, "1")));
Assert.IsTrue(secondDiffs[0].ValueEquals(new WordDiffObject(0, 0, "first ")));
Assert.IsTrue(secondDiffs[1].ValueEquals(new WordDiffObject(0, 0, "fourth-")));
//test a sorted diff
differ.Properties.Sorted = true;
result = differ.DoDiff(text1, text2);
firstDiffs = result.DifferencesForFirst;
secondDiffs = result.DifferencesForSecond;
Assert.IsTrue(firstDiffs[0].ValueEquals(new LetterDiffObject(0, 0, "1")));
Assert.IsTrue(secondDiffs[0].ValueEquals(new WordDiffObject(0, 0, "fourth-")));
}
public void LinesDiff()
{
string text1 = "LineLine1.1\r\n" +
"eniLLine1.3\r\n" +
"ABC1.4";
string text2 = "LineLine2.1\r\n" +
"XYZ2.4\r\n" +
"eniLLine2.3";
LinesDiffer differ = new LinesDiffer();
DiffResult result = differ.DoDiff(text1, text2);
IDiffObjectsCollection firstDiffs = result.DifferencesForFirst;
IDiffObjectsCollection secondDiffs = result.DifferencesForSecond;
firstDiffs.SortByPosition();
secondDiffs.SortByPosition();
Assert.IsTrue(firstDiffs[0].ValueEquals(new LetterDiffObject(0, 0, "1")));
Assert.IsTrue(secondDiffs[0].ValueEquals(new LetterDiffObject(0, 0, "2")));
Assert.IsTrue(firstDiffs[1].ValueEquals(new LetterDiffObject(0, 0, "1")));
Assert.IsTrue(secondDiffs[1].ValueEquals(new LineDiffObject(0, 0, "XYZ2.4")));
Assert.IsTrue(firstDiffs[2].ValueEquals(new LineDiffObject(0, 0, "ABC1.4")));
Assert.IsTrue(secondDiffs[2].ValueEquals(new LetterDiffObject(0, 0, "2")));
}
public void AddRange(IDiffObjectsCollection collection)
{
if (collection != null)
{
Items.AddRange(collection.Items);
}
}
private string PrintTextDifferences(IDiffObjectsCollection diff)
{
StringBuilder result = new StringBuilder();
for (int i = 0; i < diff.Count; i++)
{
result.Append((diff[i] as BaseTextDiffObject).Value);
result.Append(" ");
}
return(result.ToString());
}
private string GetRtf(string text, IDiffObjectsCollection differences)
{
int i, n = differences.Count;
RtfHighlight[] diffHighlights = new RtfHighlight[n];
for (i = 0; i < n; i++)
{
diffHighlights[i] = new RtfHighlight(differences[i]);
diffHighlights[i].Color = TVColorConverter.GetColorFromString(TrafficViewerOptions.Instance.ColorDiffText);
}
return(_builder.Convert(text, diffHighlights));
}
public void LettersDiff()
{
string text1 = "abcdefg;1";
string text2 = "xabcdfg1!";
LettersDiffer differ = new LettersDiffer();
DiffResult result = differ.DoDiff(text1, text2);
IDiffObjectsCollection firstDiffs = result.DifferencesForFirst;
IDiffObjectsCollection secondDiffs = result.DifferencesForSecond;
Assert.IsTrue(firstDiffs[0].ValueEquals(new LetterDiffObject(0, 0, "e")));
Assert.IsTrue(firstDiffs[1].ValueEquals(new LetterDiffObject(0, 0, ";")));
Assert.IsTrue(secondDiffs[0].ValueEquals(new LetterDiffObject(0, 0, "x")));
Assert.IsTrue(secondDiffs[1].ValueEquals(new LetterDiffObject(0, 0, "!")));
}
/// <summary>
/// Diffs the two collections using the ValueEquals function of their elements and stores differences in the
/// arguments collection
/// </summary>
/// <param name="first"></param>
/// <param name="second"></param>
public double Diff(ref IDiffObjectsCollection first, ref IDiffObjectsCollection second)
{
double similarity = 0.0;
if ((first == null || first.Count == 0) && second != null)
{
second.Differences = second;
}
else if ((second == null || second.Count == 0) && first != null)
{
first.Differences = first;
}
else
{
//use the LCS algorith to compute the longest common subsequence and populate the Differences in first and second
similarity = LCS(ref first, ref second);
}
return(similarity);
}
protected double DoDiff(IDiffObjectsCollection first, IDiffObjectsCollection second)
{
first.InitDiffs();
second.InitDiffs();
first.InitCommonElements();
second.InitCommonElements();
if (_properties.Sorted)
{
first.SortByValues(_properties.CaseInSensitiveSort);
second.SortByValues(_properties.CaseInSensitiveSort);
//replace the default LCS algorithm with a simple algorithm for sorted collections
_algorithm = new SortedCollectionsDiffAlgorithm();
}
first.AllowMerges = _properties.AllowMerges;
second.AllowMerges = _properties.AllowMerges;
return(_algorithm.Diff(ref first, ref second));
}
/// <summary>
/// Checks is the value is equal. If not where applicable a collection of granular differences is outputed
/// </summary>
/// <param name="diffObject"></param>
/// <param name="diffsForSelf"></param>
/// <param name="diffsForArgument"></param>
/// <param name="commonElements"></param>
/// <returns></returns>
public bool ValueMatches(IDiffObject diffObject, out IDiffObjectsCollection diffsForSelf, out IDiffObjectsCollection diffsForArgument, out IDiffObjectsCollection commonElements)
{
BaseTextDiffObject otherObject = diffObject as BaseTextDiffObject;
diffsForSelf = null;
diffsForArgument = null;
commonElements = null;
bool matches = false;
if (otherObject != null)
{
matches = this.ValueHash == otherObject.ValueHash;
if (!matches)
{
double simFactor = ASESimilarityAlgorithm.CalculateSimilarity(this.Value, otherObject.Value);
LettersDiffer granularDiffer = InitGranularDiffer();
if (simFactor > 0 && granularDiffer != null)
{
//calculate granular differences
granularDiffer.AddTask(Value, Position); //imports the current word into a letters collection starting from the position of the current element
granularDiffer.AddTask(otherObject.Value, otherObject.Position);
double diffRatio = granularDiffer.DoDiff(0, 1);
diffsForSelf = granularDiffer.GetResultingDifferences(0);
diffsForArgument = granularDiffer.GetResultingDifferences(1);
commonElements = granularDiffer.GetResultingCommonElements(0);
matches = diffRatio >= this.SimilarityFactor;
}
}
}
return(matches);
}
private void DiffWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
_progress.Visible = false;
_timer.Stop();
RequestsDifferResult result = e.Result as RequestsDifferResult;
if (result != null)
{
_labelSimilarity.Text = String.Format(Properties.Resources.SimilarityText,
result.BodyAproximateSimilarity * 100);
_firstDiffs = result.DiffsForFirst;
_secondDiffs = result.DiffsForSecond;
_boxFirst.Rtf = GetRtf(result.FirstText, result.DiffsForFirst);
_boxSecond.Rtf = GetRtf(result.SecondText, result.DiffsForSecond);
}
//re-enable the diff buttons
DiffButtonsSwitch(true);
_diffInProgress = false;
}
/// <summary>
/// Computes the longest common subsequence matrix between the two collections
/// </summary>
/// <param name="first"></param>
/// <param name="second"></param>
private double LCS(ref IDiffObjectsCollection first, ref IDiffObjectsCollection second)
{
int start = 0;
int firstEnd = first.Count;
int secondEnd = second.Count;
int i, j, n, m;
IDiffObjectsCollection granularDiffsForFirst = null;
IDiffObjectsCollection granularDiffsForSecond = null;
IDiffObjectsCollection granularCommonElements = null;
IDiffObjectsCollection currCommonElements = first.CommonElements;
second.CommonElements = currCommonElements;
//trim the matching items at the beggining
while (start < firstEnd && start < secondEnd && first[start].ValueMatches(second[start], out granularDiffsForFirst, out granularDiffsForSecond, out granularCommonElements))
{
//if the collections were slightly different add the small differences
first.Differences.AddRange(granularDiffsForFirst);
second.Differences.AddRange(granularDiffsForSecond);
if (granularDiffsForFirst == null && granularDiffsForSecond == null)
{
currCommonElements.Add(first[start]);
}
else
{
currCommonElements.AddRange(granularCommonElements);
}
start++;
}
//trim the matching items at the end
while (firstEnd > start && secondEnd > start && first[firstEnd - 1].ValueMatches(second[secondEnd - 1], out granularDiffsForFirst, out granularDiffsForSecond, out granularCommonElements))
{
firstEnd--;
secondEnd--;
if (granularDiffsForFirst == null && granularDiffsForSecond == null)
{
currCommonElements.Add(first[firstEnd]);
}
else
{
currCommonElements.AddRange(granularCommonElements);
}
//if the collections were slightly different insert the small differences
first.Differences.PushRange(granularDiffsForFirst);
second.Differences.PushRange(granularDiffsForSecond);
}
m = firstEnd - start + 1;
n = secondEnd - start + 1;
//truncate the matrix to prevent OOM
m = Math.Min(m, MAX_MATRIX_LENGTH);
n = Math.Min(n, MAX_MATRIX_LENGTH);
//create the matrix for LCS
ushort[,] C = new ushort[m, n];
for (i = 1; i < m; i++)
{
for (j = 1; j < n; j++)
{
if (first[start + i - 1].ValueMatches(second[start + j - 1]))
{
C[i, j] = (ushort)(C[i - 1, j - 1] + 1);
}
else
{
C[i, j] = Math.Max(C[i, j - 1], C[i - 1, j]);
}
}
}
//populate the differences
return(ExtractDiffs(C, first, second, start, m, n));
}
/// <summary>
/// Adds a task to be compared
/// </summary>
/// <param name="task"></param>
/// <returns>Index of the added task</returns>
public int AddTask(IDiffObjectsCollection task)
{
_collections.Add(task);
return(_collections.Count - 1);
}
private double ExtractDiffs(
ushort[, ] C, IDiffObjectsCollection first, IDiffObjectsCollection second, int start, int m, int n)
{
int i = m - 1, j = n - 1;
double diffCount1 = 0;
double diffCount2 = 0;
IDiffObjectsCollection currFirstDiffs = first.Differences;
IDiffObjectsCollection currSecondDiffs = second.Differences;
IDiffObjectsCollection currCommonElements = first.CommonElements;
second.CommonElements = currCommonElements;
do
{
int iIndex = start + i - 1;
int jIndex = start + j - 1;
IDiffObject currFirst = null;
IDiffObject currSecond = null;
IDiffObjectsCollection granularDiffsForFirst = null;
IDiffObjectsCollection granularDiffsForSecond = null;
IDiffObjectsCollection granularCommonElements = null;
if (iIndex >= 0 && iIndex < first.Count)
{
currFirst = first[iIndex];
}
if (jIndex >= 0 && jIndex < second.Count)
{
currSecond = second[jIndex];
}
if (currFirst != null &&
currFirst.ValueMatches(currSecond, out granularDiffsForFirst, out granularDiffsForSecond, out granularCommonElements))
{
//ValuesMatch can return true if the objects are very similar
//In that case we need to capture granular differences
currFirstDiffs.PushRange(granularDiffsForFirst);
currSecondDiffs.PushRange(granularDiffsForSecond);
if (granularDiffsForFirst == null && granularDiffsForSecond == null)
{
currCommonElements.Add(currFirst);
}
else
{
currCommonElements.AddRange(granularCommonElements);
}
i--; j--;
}
else if (j > 0 && (i <= 0 || C[i, j - 1] >= C[i - 1, j]))
{
currSecondDiffs.Push(currSecond);
diffCount2++;
j--;
}
else if (i > 0 && (j <= 0 || C[i, j - 1] < C[i - 1, j]))
{
currFirstDiffs.Push(currFirst);
diffCount1++;
i--;
}
}while (i > 0 || j > 0);
//calculate diff ratio, or similarity factor
double ratio1 = 0;
if (first.Count > 0)
{
ratio1 = 1 - diffCount1 / first.Count;
}
double ratio2 = 0;
if (second.Count > 0)
{
ratio2 = 1 - diffCount2 / second.Count;
}
return(Math.Min(ratio1, ratio2));
}
public double Diff(ref IDiffObjectsCollection first, ref IDiffObjectsCollection second)
{
int i = 0, j = 0, m = first.Count, n = second.Count;
double diffCount1 = 0;
double diffCount2 = 0;
IDiffObjectsCollection granularDiffs1 = null;
IDiffObjectsCollection granularDiffs2 = null;
IDiffObjectsCollection granularCommon = null;
IDiffObjectsCollection currCommonElements = first.CommonElements;
second.CommonElements = currCommonElements;
while (i < m || j < n)
{
if (j < n && i < m && first[i].ValueMatches(second[j], out granularDiffs1, out granularDiffs2, out granularCommon))
{
first.Differences.AddRange(granularDiffs1);
second.Differences.AddRange(granularDiffs2);
if (granularDiffs1 == null && granularDiffs2 == null)
{
currCommonElements.Add(first[i]);
}
else
{
currCommonElements.AddRange(granularCommon);
}
i++;
j++;
}
else if (i < m && (j >= n || first[i].CompareValues(second[j], _ignoreCase) == CompareResult.Lower))
{
first.Differences.Add(first[i]);
diffCount1++;
i++;
}
else if (j < n && (i >= m || first[i].CompareValues(second[j], _ignoreCase) == CompareResult.Greater))
{
second.Differences.Add(second[j]);
diffCount2++;
j++;
}
}
//calculate diff ratio, or similarity factor
double ratio1 = 0;
if (first.Count > 0)
{
ratio1 = 1 - diffCount1 / first.Count;
}
double ratio2 = 0;
if (second.Count > 0)
{
ratio2 = 1 - diffCount2 / second.Count;
}
return(Math.Min(ratio1, ratio2));
}