public static SignatureHelpSession TryCreate(SnapshotPoint triggerPosition, SignatureHelpTriggerInfo triggerInfo, Lazy<ISignatureHelpBroker> signatureHelpBroker, ITextView textView) {
var info = SignatureHelpInfo.Create(triggerPosition.Snapshot);
if (info == null)
return null;
if (triggerInfo.TriggerReason == SignatureHelpTriggerReason.TypeCharCommand) {
Debug.Assert(triggerInfo.TriggerCharacter != null);
if (triggerInfo.TriggerCharacter != null && !info.Value.SignatureHelpService.IsTriggerCharacter(triggerInfo.TriggerCharacter.Value))
return null;
}
else if (triggerInfo.TriggerReason == SignatureHelpTriggerReason.RetriggerCommand) {
if (triggerInfo.TriggerCharacter != null && !info.Value.SignatureHelpService.IsRetriggerCharacter(triggerInfo.TriggerCharacter.Value))
return null;
}
return new SignatureHelpSession(info.Value.SignatureHelpService, signatureHelpBroker, textView);
}
public async Task <SignatureHelpResult> GetItemsAsync(Document document, int position, SignatureHelpTriggerInfo triggerInfo, CancellationToken cancellationToken = default(CancellationToken))
{
var res = await ComputeItemsAsync(signatureHelpProviders, position, triggerInfo.ToSignatureHelpTriggerInfo(), document, cancellationToken).ConfigureAwait(false);
return(GetSignatureHelpResult(res, document));
}
void TriggerSession(SignatureHelpTriggerInfo triggerInfo) {
var position = textView.Caret.Position.BufferPosition;
if (session == null) {
session = SignatureHelpSession.TryCreate(position, triggerInfo, signatureHelpBroker, textView);
if (session == null)
return;
session.Disposed += SignatureHelpSession_Disposed;
}
session.Restart(position, triggerInfo);
}
bool RestartCore(SnapshotPoint triggerPosition, SignatureHelpTriggerInfo triggerInfo) {
var info = SignatureHelpInfo.Create(triggerPosition.Snapshot);
if (info == null)
return false;
Start(info.Value, triggerPosition, triggerInfo);
return true;
}
public void Restart(SnapshotPoint triggerPosition, SignatureHelpTriggerInfo triggerInfo) {
if (!RestartCore(triggerPosition, triggerInfo))
Dispose();
}
async Task StartAsync(SignatureHelpInfo info, SnapshotPoint triggerPosition, SignatureHelpTriggerInfo triggerInfo, CancellationToken cancellationToken) {
// This helps a little to speed up the code
ProfileOptimizationHelper.StartProfile("roslyn-sighelp-" + info.SignatureHelpService.Language);
var result = await info.SignatureHelpService.GetItemsAsync(info.Document, triggerPosition.Position, triggerInfo, cancellationToken);
if (result == null) {
Dispose();
return;
}
if (cancellationToken.IsCancellationRequested)
return;
StartSession(triggerPosition, result);
}
void Start(SignatureHelpInfo info, SnapshotPoint triggerPosition, SignatureHelpTriggerInfo triggerInfo) {
CancelFetchItems();
Debug.Assert(cancellationTokenSource == null);
cancellationTokenSource = new CancellationTokenSource();
var cancellationTokenSourceTmp = cancellationTokenSource;
StartAsync(info, triggerPosition, triggerInfo, cancellationTokenSource.Token)
.ContinueWith(t => {
var ex = t.Exception;
// Free resources
if (cancellationTokenSource == cancellationTokenSourceTmp)
CancelFetchItems();
}, CancellationToken.None, TaskContinuationOptions.None, TaskScheduler.FromCurrentSynchronizationContext());
}
async Task InitializeAsync(ITextBuffer buffer, string code, MetadataReference[] refs, string languageName, ISynchronousTagger<IClassificationTag> tagger, CompilationOptions compilationOptions, ParseOptions parseOptions) {
using (var workspace = new AdhocWorkspace(RoslynMefHostServices.DefaultServices)) {
var documents = new List<DocumentInfo>();
var projectId = ProjectId.CreateNewId();
documents.Add(DocumentInfo.Create(DocumentId.CreateNewId(projectId), "main.cs", null, SourceCodeKind.Regular, TextLoader.From(buffer.AsTextContainer(), VersionStamp.Create())));
var projectInfo = ProjectInfo.Create(projectId, VersionStamp.Create(), "compilecodeproj", Guid.NewGuid().ToString(), languageName,
compilationOptions: compilationOptions
.WithOptimizationLevel(OptimizationLevel.Release)
.WithPlatform(Platform.AnyCpu)
.WithAssemblyIdentityComparer(DesktopAssemblyIdentityComparer.Default),
parseOptions: parseOptions,
documents: documents,
metadataReferences: refs,
isSubmission: false, hostObjectType: null);
workspace.AddProject(projectInfo);
foreach (var doc in documents)
workspace.OpenDocument(doc.Id);
buffer.Replace(new Span(0, buffer.CurrentSnapshot.Length), code);
{
// Initialize classification code paths
var spans = new NormalizedSnapshotSpanCollection(new SnapshotSpan(buffer.CurrentSnapshot, 0, buffer.CurrentSnapshot.Length));
foreach (var tagSpan in tagger.GetTags(spans, CancellationToken.None)) { }
}
{
// Initialize completion code paths
var info = CompletionInfo.Create(buffer.CurrentSnapshot);
Debug.Assert(info != null);
if (info != null) {
var completionTrigger = CompletionTrigger.Default;
var completionList = await info.Value.CompletionService.GetCompletionsAsync(info.Value.Document, 0, completionTrigger);
}
}
{
// Initialize signature help code paths
var info = SignatureHelpInfo.Create(buffer.CurrentSnapshot);
Debug.Assert(info != null);
if (info != null) {
int sigHelpIndex = code.IndexOf("sighelp");
Debug.Assert(sigHelpIndex >= 0);
var triggerInfo = new SignatureHelpTriggerInfo(SignatureHelpTriggerReason.InvokeSignatureHelpCommand);
var items = await info.Value.SignatureHelpService.GetItemsAsync(info.Value.Document, sigHelpIndex, triggerInfo);
}
}
{
// Initialize quick info code paths
var info = QuickInfoState.Create(buffer.CurrentSnapshot);
Debug.Assert(info != null);
if (info != null) {
int quickInfoIndex = code.IndexOf("Equals");
Debug.Assert(quickInfoIndex >= 0);
var item = await info.Value.QuickInfoService.GetItemAsync(info.Value.Document, quickInfoIndex);
}
}
}
}