private void ExtendStartPoint()
{
//some are not extended
if (!Complete
|| StartLine.LineNumber == EndLine.LineNumber
|| !string.IsNullOrWhiteSpace(TextBefore)) return;
//how much can we move region start
int upperLimit = 0;
if (this.Parent != null)
{
int childPosition = Parent.Children.IndexOf(this);
if (childPosition == 0)
{
//this region is first child of its parent
//we can go until the parent's start
upperLimit = Parent.RegionType != TextRegionType.None ? Parent.StartLine.LineNumber + 1 : 0;
}
else
{
//there is previous child
//we can go until its end
TextRegion prevRegion = Parent.Children[childPosition - 1];
upperLimit = prevRegion.EndLine.LineNumber + (prevRegion.EndLine.LineNumber == prevRegion.StartLine.LineNumber ? 0 : 1);
}
}
//now looking up to calculated upper limit for non-empty line
for (int i = StartLine.LineNumber - 1; i >= upperLimit; i--)
{
ITextSnapshotLine line = StartPoint.Snapshot.GetLineFromLineNumber(i);
if (!string.IsNullOrWhiteSpace(line.GetText()))
{
//found such line, placing region start at its end
StartPoint = line.End;
return;
}
}
}
/// <summary>
/// parses buffer
/// </summary>
/// <param name="parser"></param>
/// <param name="parent">parent region or null</param>
/// <returns>a region with its children or null</returns>
public static TextRegion ParseBuffer(SnapshotParser parser, TextRegion parent)
{
for (; !parser.AtEnd(); parser.MoveNext())
{
TextRegion r = TextRegion.TryCreateRegion(parser);
if (r != null)
{
parser.MoveNext();
//found the start of the region
if (!r.Complete)
{
//searching for child regions
while (TextRegion.ParseBuffer(parser, r) != null)
{
;
}
//found everything
r.ExtendStartPoint();
}
//adding to children or merging with last child
r.Parent = parent;
parent.Children.Add(r);
return(r);
}
//found parent's end - terminating parsing
if (parent.TryComplete(parser))
{
parser.MoveNext();
return(null);
}
}
return(null);
}