private void DoUpdate()
{
// It would be good to do all of this work on a background thread but we can't:
// _classifier.GetClassificationSpans() should only be called on the UI thread because some classifiers assume they are called from the UI thread.
// Raising the TagsChanged event from the taggers needs to happen on the UI thread (because some consumers might assume it is being raised on the UI thread).
//
// Updating the snapshot for the factory and calling the sink can happen on any thread but those operations are so fast that there is no point.
if ((!_isDisposed) && (_dirtySpans.Count > 0))
{
var line = _dirtySpans[0].Start.GetContainingLine();
if (line.Length > 0)
{
var oldSecurityErrors = this.Factory.CurrentSnapshot;
var newSecurityErrors = new DevSkimErrorsSnapshot(this.FilePath, oldSecurityErrors.VersionNumber + 1);
// Go through the existing errors. If they are on the line we are currently parsing then
// copy them to oldLineErrors, otherwise they go to the new errors.
var oldLineErrors = new List <DevSkimError>();
foreach (var error in oldSecurityErrors.Errors)
{
Debug.Assert(error.NextIndex == -1);
if (line.Extent.Contains(error.Span))
{
error.NextIndex = -1;
oldLineErrors.Add(error); // Do not clone old error here ... we'll do that later there is no change.
}
else
{
error.NextIndex = newSecurityErrors.Errors.Count;
newSecurityErrors.Errors.Add(DevSkimError.Clone(error)); // We must clone the old error here.
}
}
int expectedErrorCount = newSecurityErrors.Errors.Count + oldLineErrors.Count;
bool anyNewErrors = false;
// provide whole line to processor so it has complete overview of the scanned code
string text = line.GetText();
//var classifications = _classifier.GetClassificationSpans(line.Extent);
//foreach (var classification in classifications)
//{
//if (classification.ClassificationType.IsOfType(PredefinedClassificationTypeNames.Comment) || classification.ClassificationType.IsOfType("xml doc comment - text"))
// classification.Span.GetText();
int index = 0;
while (index < text.Length)
{
MatchResult result = RuleProcessor.IsMatch(text, index, line.Snapshot.ContentType.TypeName);
int errorStart = result.Location;
if (errorStart < 0)
{
break;
}
int errorLength = result.Length;
if (errorLength > 0) // Ignore any single character error.
{
//var newSpan = new SnapshotSpan(classification.Span.Start + errorStart, errorLength);
var newSpan = new SnapshotSpan(line.Start + errorStart, errorLength);
var oldError = oldLineErrors.Find((e) => e.Span == newSpan);
if (oldError != null)
{
// There was a security error at the same span as the old one so we should be able to just reuse it.
oldError.NextIndex = newSecurityErrors.Errors.Count;
newSecurityErrors.Errors.Add(DevSkimError.Clone(oldError)); // Don't clone the old error yet
}
else
{
newSecurityErrors.Errors.Add(new DevSkimError(newSpan, result.Rule));
anyNewErrors = true;
}
index = errorStart + errorLength;
}
else
{
// How can you have a error with a length of 0? Handle it gracefully in any case.
index = errorStart + 1;
}
}
//endforeach}
// This does a deep comparison so we will only do the update if the a different set of errors was discovered compared to what we had previously.
// If there were any new errors or if we didn't see all the expected errors then there is a change and we need to update the security errors.
if (anyNewErrors || (newSecurityErrors.Errors.Count != expectedErrorCount))
{
this.UpdateSecurityErrors(newSecurityErrors);
}
else
{
// There were no changes so we don't need to update our snapshot.
// We have, however, dirtied the old errors by setting their NextIndex property on the assumption that we would be updating the errors.
// Revert all those changes.
foreach (var error in oldSecurityErrors.Errors)
{
error.NextIndex = -1;
}
}
}
// NormalizedSnapshotSpanCollection.Difference doesn't quite do what we need here. If I have {[5,5), [10,20)} and subtract {[5, 15)} and do a ...Difference, I
// end up with {[5,5), [15,20)} (the zero length span at the beginning isn't getting removed). A zero-length span at the end wouldn't be removed but, in this case,
// that is the desired behavior (the zero length span at the end could be a change at the beginning of the next line, which we'd want to keep).
var newDirtySpans = new List <Span>(_dirtySpans.Count + 1);
var extent = line.ExtentIncludingLineBreak;
for (int i = 0; (i < _dirtySpans.Count); ++i)
{
Span s = _dirtySpans[i];
if ((s.End < extent.Start) || (s.Start >= extent.End)) // Intentionally asymmetric
{
newDirtySpans.Add(s);
}
else
{
if (s.Start < extent.Start)
{
newDirtySpans.Add(Span.FromBounds(s.Start, extent.Start));
}
if ((s.End >= extent.End) && (extent.End < line.Snapshot.Length))
{
newDirtySpans.Add(Span.FromBounds(extent.End, s.End)); //This could add a zero length span (which is by design since we want to ensure we security check the next line).
}
}
}
_dirtySpans = new NormalizedSnapshotSpanCollection(line.Snapshot, newDirtySpans);
if (_dirtySpans.Count == 0)
{
// We've cleaned up all the dirty spans.
_isUpdating = false;
}
else
{
// Still more work to do.
_uiThreadDispatcher.BeginInvoke(new Action(() => this.DoUpdate()), DispatcherPriority.Background);
}
}
}
/// <summary>
/// Test given text for issues
/// </summary>
/// <param name="text">Source code</param>
/// <param name="contenttype">Visual Studio content type</param>
/// <returns>MatchRecord with infomartion of identified issue</returns>
private MatchResult FindMatch(string text, string contenttype)
{
// Get rules for the given content type
IEnumerable <Rule> rules = GetRulesForContentType(contenttype);
MatchResult result = new MatchResult()
{
Success = false
};
// Go through each rule
foreach (Rule r in rules)
{
// Go through each matching pattern of the rule
foreach (PatternRecord p in r.Patterns)
{
// Type == Substring
if (p.Type == PatternType.Substring)
{
result.Location = text.ToLower().IndexOf(p.Pattern.ToLower());
result.Length = p.Pattern.Length;
if (result.Location > -1)
{
result.Success = true;
result.Rule = r;
break; // from pattern loop
}
}
// Type == Regex
else if (p.Type == PatternType.Regex)
{
RegexOptions reopt = RegexOptions.None;
if (p.Modifiers != null)
{
reopt |= (p.Modifiers.Contains("ignorecase")) ? RegexOptions.IgnoreCase : RegexOptions.None;
reopt |= (p.Modifiers.Contains("multiline")) ? RegexOptions.Multiline : RegexOptions.None;
}
Regex patRegx = new Regex(p.Pattern, reopt);
Match m = patRegx.Match(text);
if (m.Success)
{
result.Success = true;
result.Rule = r;
result.Location = m.Index;
result.Length = m.Length;
break; // from pattern loop
}
}
}
// We got matching rule. Let's see if we have a supression on the line
if (result.Success)
{
Suppressor supp = new Suppressor(_textLine, contenttype);
// If rule is being suppressed then clear the MatchResult
if (supp.IsRuleSuppressed(result.Rule.Id))
{
result = new MatchResult();
}
// Otherwise break out of the loop as we found an issue.
// So, no need to scan for more.
else
{
break;
}
}
}
return(result);
}