private void TokenFromPosition(ITextSnapshot snapshot, int position, out int itemIndex, out int offset)
{
// Normally token stream does not change after formatting so we can simply rely on the fact
// that caret position is going to remain relative to the same token index
itemIndex = -1;
offset = 0;
// Expand range to include the next line. This is needed when user introduces line break.
var lineNumber = snapshot.GetLineNumberFromPosition(_changingRange.End);
if (lineNumber < snapshot.LineCount - 1)
{
var end = snapshot.GetLineFromLineNumber(lineNumber + 1).End;
_changingRange = TextRange.FromBounds(_changingRange.Start, end);
}
var tokenizer = new RTokenizer();
IReadOnlyTextRangeCollection <RToken> tokens =
tokenizer.Tokenize(new TextProvider(snapshot), _changingRange.Start, _changingRange.Length, true);
// Check if position is adjacent to previous token
int prevItemIndex = tokens.GetFirstItemBeforePosition(position);
if (prevItemIndex >= 0 && tokens[prevItemIndex].End == position)
{
itemIndex = prevItemIndex;
offset = -tokens[itemIndex].Length;
return;
}
int nextItemIndex = tokens.GetFirstItemAfterOrAtPosition(position);
if (nextItemIndex >= 0)
{
// If two tokens are adjacent, gravity is negative, i.e. caret travels
// with preceding token so it won't just to aniother line if, say,
// formatter decides to insert a new line between tokens.
if (nextItemIndex > 0 && tokens[nextItemIndex - 1].End == tokens[nextItemIndex].Start)
{
nextItemIndex--;
}
offset = tokens[nextItemIndex].Start - position;
itemIndex = nextItemIndex;
return;
}
// We are past last token
if (tokens.Count > 0)
{
itemIndex = tokens.Count - 1;
offset = tokens[itemIndex].Start - position;
}
else
{
itemIndex = -1;
offset = position;
}
}
private static void TokenFromPosition(ITextSnapshot snapshot, int position, out int itemIndex, out int offset)
{
// Normally token stream does not change after formatting so we can simply rely on the fact
// that caret position is going to remain relative to the same token index
itemIndex = -1;
offset = 0;
var tokenizer = new RTokenizer();
IReadOnlyTextRangeCollection <RToken> tokens = tokenizer.Tokenize(new TextProvider(snapshot), 0, snapshot.Length, true);
// Check if position is adjacent to previous token
int prevItemIndex = tokens.GetFirstItemBeforePosition(position);
if (prevItemIndex >= 0 && tokens[prevItemIndex].End == position)
{
itemIndex = prevItemIndex;
offset = -tokens[itemIndex].Length;
return;
}
int nextItemIndex = tokens.GetFirstItemAfterOrAtPosition(position);
if (nextItemIndex >= 0)
{
// If two tokens are adjacent, gravity is negative, i.e. caret travels
// with preceding token so it won't just to aniother line if, say,
// formatter decides to insert a new line between tokens.
if (nextItemIndex > 0 && tokens[nextItemIndex - 1].End == tokens[nextItemIndex].Start)
{
nextItemIndex--;
}
offset = tokens[nextItemIndex].Start - position;
itemIndex = nextItemIndex;
return;
}
// We are past last token
if (tokens.Count > 0)
{
itemIndex = tokens.Count - 1;
offset = tokens[itemIndex].Start - position;
}
else
{
itemIndex = -1;
offset = position;
}
}