internal ITextSnapshot AdvanceToCurrentSnapshot()
{
//We don't need to take a snapshot of the results because the results are only modified on this thread.
ITextSnapshot oldSnapshot = _results.Snapshot;
ITextSnapshot newSnapshot = _buffer.CurrentSnapshot;
if (oldSnapshot != newSnapshot)
{
//The results are all on an old snapshot. We need to project them forward (even though that might cause some stale and incorrect
//results).
NormalizedSpanCollection newMatches = TextSearchNavigator.TranslateTo(oldSnapshot, _results.Matches, newSnapshot);
NormalizedSpanCollection newSearchedSpans = NormalizedSpanCollection.Empty;
if ((_results.SearchedSpans.Count != 0) && !_options.HasFlag(FindOptions.Multiline))
{
//Advance our record of the spans that have already been searched to the new snapshot as well.
newSearchedSpans = BackgroundSearch <T> .TranslateToAndExtend(oldSnapshot, _results.SearchedSpans, newSnapshot);
//But remove anything on a TextSnapshotLine that was modified by the change.
List <Span> changedSpansOnNewSnapshot = new List <Span>();
ITextVersion version = oldSnapshot.Version;
while (version != newSnapshot.Version)
{
foreach (var change in version.Changes)
{
changedSpansOnNewSnapshot.Add(BackgroundSearch <T> .Extend(newSnapshot, Tracking.TrackSpanForwardInTime(SpanTrackingMode.EdgeInclusive, change.NewSpan,
version.Next, newSnapshot.Version)));
}
version = version.Next;
}
if (changedSpansOnNewSnapshot.Count > 0)
{
NormalizedSpanCollection changes = new NormalizedSpanCollection(changedSpansOnNewSnapshot);
//Remove the spans touched by changes from the spans we've searched
newSearchedSpans = NormalizedSpanCollection.Difference(newSearchedSpans, changes);
}
}
_results = new SearchResults(newSnapshot, newMatches, newSearchedSpans);
}
return(newSnapshot);
}
public static NormalizedSpanCollection TranslateToAndExtend(ITextSnapshot currentSnapshot, NormalizedSpanCollection currentSpans, ITextSnapshot targetSnapshot)
{
if (currentSpans.Count == 0)
{
return(currentSpans);
}
List <Span> spans = new List <Span>(currentSpans.Count);
foreach (var s in currentSpans)
{
spans.Add(BackgroundSearch <T> .Extend(targetSnapshot, Tracking.TrackSpanForwardInTime(SpanTrackingMode.EdgeNegative,
s,
currentSnapshot.Version, targetSnapshot.Version)));
}
return(new NormalizedSpanCollection(spans));
}