private static SnapshotSpan AsSnapshotSpan(SimpleRegion region, ITextSnapshot snapshot)
{
var startLine = snapshot.GetLineFromLineNumber(region.StartLine);
var endLine = (region.StartLine == region.EndLine)
? startLine
: snapshot.GetLineFromLineNumber(region.EndLine);
return(new SnapshotSpan(startLine.Start + region.StartOffset, endLine.End));
}
internal SimpleRegion(SimpleRegion clone) : base(clone)
{
}
private void ReParse()
{
ITextSnapshot newSnapshot = this.buffer.CurrentSnapshot;
var newRegions = new List <SimpleRegion>();
SimpleRegion currentRegion = null;
foreach (var line in newSnapshot.Lines)
{
string text = line.GetText();
var trimText = text.Trim();
var isCommentOfInterest = false;
if (trimText == "//" || trimText == "////" ||
trimText.StartsWith("// ") || trimText.StartsWith("////"))
{
isCommentOfInterest = true;
}
if (isCommentOfInterest)
{
if (currentRegion == null)
{
currentRegion = new SimpleRegion
{
StartLine = line.LineNumber,
StartOffset = text.IndexOf("//"),
};
}
}
else
{
if (currentRegion != null)
{
var endLineNumber = line.LineNumber - 1;
if (endLineNumber != currentRegion.StartLine)
{
currentRegion.EndLine = endLineNumber;
newRegions.Add(currentRegion);
}
currentRegion = null;
}
}
}
if (currentRegion != null)
{
var endLineNumber = newSnapshot.Lines.Count() - 1;
if (endLineNumber != currentRegion.StartLine)
{
currentRegion.EndLine = endLineNumber;
newRegions.Add(currentRegion);
}
}
// determine the changed span, and send a changed event with the new spans
List <Span> oldSpans =
new List <Span>(this.regions.Select(r => AsSnapshotSpan(r, this.snapshot)
.TranslateTo(newSnapshot, SpanTrackingMode.EdgeExclusive)
.Span));
List <Span> newSpans =
new List <Span>(newRegions.Select(r => AsSnapshotSpan(r, newSnapshot).Span));
NormalizedSpanCollection oldSpanCollection = new NormalizedSpanCollection(oldSpans);
NormalizedSpanCollection newSpanCollection = new NormalizedSpanCollection(newSpans);
// the changed regions are regions that appear in one set or the other, but not both.
NormalizedSpanCollection removed =
NormalizedSpanCollection.Difference(oldSpanCollection, newSpanCollection);
int changeStart = int.MaxValue;
int changeEnd = -1;
if (removed.Count > 0)
{
changeStart = removed[0].Start;
changeEnd = removed[removed.Count - 1].End;
}
if (newSpans.Count > 0)
{
changeStart = Math.Min(changeStart, newSpans[0].Start);
changeEnd = Math.Max(changeEnd, newSpans[newSpans.Count - 1].End);
}
this.snapshot = newSnapshot;
this.regions = newRegions;
if (changeStart <= changeEnd)
{
ITextSnapshot snap = this.snapshot;
this.TagsChanged?.Invoke(
this,
new SnapshotSpanEventArgs(
new SnapshotSpan(this.snapshot, Span.FromBounds(changeStart, changeEnd))));
}
}
