protected override async Task ProduceTagsAsync(TaggerContext <KeywordHighlightTag> context, DocumentSnapshotSpan documentSnapshotSpan, int?caretPosition)
{
var cancellationToken = context.CancellationToken;
var document = documentSnapshotSpan.Document;
// https://devdiv.visualstudio.com/DevDiv/_workitems/edit/763988
// It turns out a document might be associated with a project of wrong language, e.g. C# document in a Xaml project.
// Even though we couldn't repro the crash above, a fix is made in one of possibly multiple code paths that could cause
// us to end up in this situation.
// Regardless of the effective of the fix, we want to enhance the guard against such scenario here until an audit in
// workspace is completed to eliminate the root cause.
if (document?.SupportsSyntaxTree != true)
{
return;
}
var documentOptions = await document.GetOptionsAsync(cancellationToken).ConfigureAwait(false);
if (!documentOptions.GetOption(FeatureOnOffOptions.KeywordHighlighting))
{
return;
}
if (!caretPosition.HasValue)
{
return;
}
var snapshotSpan = documentSnapshotSpan.SnapshotSpan;
var position = caretPosition.Value;
var snapshot = snapshotSpan.Snapshot;
// 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(new SnapshotPoint(snapshot, position));
if (!existingTags.IsEmpty())
{
context.SetSpansTagged(SpecializedCollections.EmptyEnumerable <DocumentSnapshotSpan>());
return;
}
using (Logger.LogBlock(FunctionId.Tagger_Highlighter_TagProducer_ProduceTags, cancellationToken))
using (s_listPool.GetPooledObject(out var highlights))
{
var root = await document.GetSyntaxRootAsync(cancellationToken).ConfigureAwait(false);
_highlightingService.AddHighlights(root, position, highlights, cancellationToken);
foreach (var span in highlights)
{
context.AddTag(new TagSpan <KeywordHighlightTag>(span.ToSnapshotSpan(snapshot), KeywordHighlightTag.Instance));
}
}
}
protected override async Task ProduceTagsAsync(TaggerContext <KeywordHighlightTag> context, DocumentSnapshotSpan documentSnapshotSpan, int?caretPosition)
{
var cancellationToken = context.CancellationToken;
var document = documentSnapshotSpan.Document;
if (document == null)
{
return;
}
var documentOptions = await document.GetOptionsAsync(cancellationToken).ConfigureAwait(false);
if (!documentOptions.GetOption(FeatureOnOffOptions.KeywordHighlighting))
{
return;
}
if (!caretPosition.HasValue)
{
return;
}
var snapshotSpan = documentSnapshotSpan.SnapshotSpan;
var position = caretPosition.Value;
var snapshot = snapshotSpan.Snapshot;
// 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(new SnapshotPoint(snapshot, position));
if (!existingTags.IsEmpty())
{
context.SetSpansTagged(SpecializedCollections.EmptyEnumerable <DocumentSnapshotSpan>());
return;
}
using (Logger.LogBlock(FunctionId.Tagger_Highlighter_TagProducer_ProduceTags, cancellationToken))
{
var root = await document.GetSyntaxRootAsync(cancellationToken).ConfigureAwait(false);
var spans = _highlightingService.GetHighlights(root, position, cancellationToken);
foreach (var span in spans)
{
context.AddTag(new TagSpan <KeywordHighlightTag>(span.ToSnapshotSpan(snapshot), KeywordHighlightTag.Instance));
}
}
}
protected override Task ProduceTagsAsync(TaggerContext <NavigableHighlightTag> context)
{
// 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;
if (!Workspace.TryGetWorkspace(caretPosition.Snapshot.AsText().Container, out var workspace))
{
return(Task.CompletedTask);
}
// 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 (!workspace.Options.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(SpecializedCollections.EmptyEnumerable <DocumentSnapshotSpan>());
return(Task.CompletedTask);
}
// Otherwise, we need to go produce all tags.
return(ProduceTagsAsync(context, caretPosition, document));
}