private async Task <ImmutableArray <DocumentHighlight> > GetReferenceHighlightsAsync(Document document, SourceText text, int position, CancellationToken cancellationToken)
{
var documentHighlightService = document.GetRequiredLanguageService <IDocumentHighlightsService>();
var options = _globalOptions.GetHighlightingOptions(document.Project.Language);
var highlights = await documentHighlightService.GetDocumentHighlightsAsync(
document,
position,
ImmutableHashSet.Create(document),
options,
cancellationToken).ConfigureAwait(false);
if (!highlights.IsDefaultOrEmpty)
{
// LSP requests are only for a single document. So just get the highlights for the requested document.
var highlightsForDocument = highlights.FirstOrDefault(h => h.Document.Id == document.Id);
return(highlightsForDocument.HighlightSpans.SelectAsArray(h => new DocumentHighlight
{
Range = ProtocolConversions.TextSpanToRange(h.TextSpan, text),
Kind = ProtocolConversions.HighlightSpanKindToDocumentHighlightKind(h.Kind),
}));
}
return(ImmutableArray <DocumentHighlight> .Empty);
}
protected override Task ProduceTagsAsync(
TaggerContext <NavigableHighlightTag> context, CancellationToken cancellationToken)
{
// NOTE(cyrusn): Normally we'd limit ourselves to producing tags in the span we were
// asked about. However, we want to produce all tags here so that the user can actually
// navigate between all of them using the appropriate tag navigation commands. If we
// don't generate all the tags then the user will cycle through an incorrect subset.
if (context.CaretPosition == null)
{
return(Task.CompletedTask);
}
var caretPosition = context.CaretPosition.Value;
// GetSpansToTag may have produced no actual spans to tag. Be resilient to that.
var document = context.SpansToTag.FirstOrDefault(vt => vt.SnapshotSpan.Snapshot == caretPosition.Snapshot).Document;
if (document == null)
{
return(Task.CompletedTask);
}
// Don't produce tags if the feature is not enabled.
if (!_globalOptions.GetOption(FeatureOnOffOptions.ReferenceHighlighting, document.Project.Language))
{
return(Task.CompletedTask);
}
// See if the user is just moving their caret around in an existing tag. If so, we don't
// want to actually go recompute things. Note: this only works for containment. If the
// user moves their caret to the end of a highlighted reference, we do want to recompute
// as they may now be at the start of some other reference that should be highlighted instead.
var existingTags = context.GetExistingContainingTags(caretPosition);
if (!existingTags.IsEmpty())
{
context.SetSpansTagged(ImmutableArray <SnapshotSpan> .Empty);
return(Task.CompletedTask);
}
// Otherwise, we need to go produce all tags.
var options = _globalOptions.GetHighlightingOptions(document.Project.Language);
return(ProduceTagsAsync(context, caretPosition, document, options, cancellationToken));
}