public async Task <LSP.CompletionList?> HandleRequestAsync(LSP.CompletionParams request, RequestContext context, CancellationToken cancellationToken)
{
var document = context.Document;
if (document == null)
{
return(null);
}
// C# and VB share the same LSP language server, and thus share the same default trigger characters.
// We need to ensure the trigger character is valid in the document's language. For example, the '{'
// character, while a trigger character in VB, is not a trigger character in C#.
if (request.Context != null &&
request.Context.TriggerKind == LSP.CompletionTriggerKind.TriggerCharacter &&
!char.TryParse(request.Context.TriggerCharacter, out var triggerCharacter) &&
!char.IsLetterOrDigit(triggerCharacter) &&
!IsValidTriggerCharacterForDocument(document, triggerCharacter))
{
return(null);
}
var position = await document.GetPositionFromLinePositionAsync(ProtocolConversions.PositionToLinePosition(request.Position), cancellationToken).ConfigureAwait(false);
var completionOptions = await GetCompletionOptionsAsync(document, cancellationToken).ConfigureAwait(false);
var completionService = document.Project.LanguageServices.GetRequiredService <CompletionService>();
// TO-DO: More LSP.CompletionTriggerKind mappings are required to properly map to Roslyn CompletionTriggerKinds.
// https://dev.azure.com/devdiv/DevDiv/_workitems/edit/1178726
var completionTrigger = await ProtocolConversions.LSPToRoslynCompletionTriggerAsync(request.Context, document, position, cancellationToken).ConfigureAwait(false);
var list = await completionService.GetCompletionsAsync(document, position, completionTrigger, options : completionOptions, cancellationToken : cancellationToken).ConfigureAwait(false);
if (list == null)
{
return(null);
}
var lspVSClientCapability = context.ClientCapabilities?.HasVisualStudioLspCapability() == true;
var commitCharactersRuleCache = new Dictionary <ImmutableArray <CharacterSetModificationRule>, ImmutableArray <string> >();
// Cache the completion list so we can avoid recomputation in the resolve handler
var resultId = await _completionListCache.UpdateCacheAsync(list, cancellationToken).ConfigureAwait(false);
return(new LSP.VSCompletionList
{
Items = list.Items.Select(item => CreateLSPCompletionItem(
request, item, resultId, lspVSClientCapability, completionTrigger, commitCharactersRuleCache)).ToArray(),
SuggestionMode = list.SuggestionModeItem != null,
});
// Local functions
bool IsValidTriggerCharacterForDocument(Document document, char triggerCharacter)
{
if (document.Project.Language == LanguageNames.CSharp)
{
return(_csharpTriggerCharacters.Contains(triggerCharacter));
}
else if (document.Project.Language == LanguageNames.VisualBasic)
{
return(_vbTriggerCharacters.Contains(triggerCharacter));
}
// Typescript still calls into this for completion.
// Since we don't know what their trigger characters are, just return true.
return(true);
}
public async Task <LSP.CompletionList?> HandleRequestAsync(LSP.CompletionParams request, RequestContext context, CancellationToken cancellationToken)
{
var document = context.Document;
if (document == null)
{
return(null);
}
// C# and VB share the same LSP language server, and thus share the same default trigger characters.
// We need to ensure the trigger character is valid in the document's language. For example, the '{'
// character, while a trigger character in VB, is not a trigger character in C#.
if (request.Context != null &&
request.Context.TriggerKind == LSP.CompletionTriggerKind.TriggerCharacter &&
!char.TryParse(request.Context.TriggerCharacter, out var triggerCharacter) &&
!char.IsLetterOrDigit(triggerCharacter) &&
!IsValidTriggerCharacterForDocument(document, triggerCharacter))
{
return(null);
}
var position = await document.GetPositionFromLinePositionAsync(ProtocolConversions.PositionToLinePosition(request.Position), cancellationToken).ConfigureAwait(false);
var completionOptions = await GetCompletionOptionsAsync(document, cancellationToken).ConfigureAwait(false);
var completionService = document.Project.LanguageServices.GetRequiredService <CompletionService>();
// TO-DO: More LSP.CompletionTriggerKind mappings are required to properly map to Roslyn CompletionTriggerKinds.
// https://dev.azure.com/devdiv/DevDiv/_workitems/edit/1178726
var completionTrigger = await ProtocolConversions.LSPToRoslynCompletionTriggerAsync(request.Context, document, position, cancellationToken).ConfigureAwait(false);
var list = await completionService.GetCompletionsAsync(document, position, completionTrigger, options : completionOptions, cancellationToken : cancellationToken).ConfigureAwait(false);
if (list == null || list.Items.IsEmpty)
{
return(null);
}
var lspVSClientCapability = context.ClientCapabilities.HasVisualStudioLspCapability() == true;
var snippetsSupported = context.ClientCapabilities.TextDocument?.Completion?.CompletionItem?.SnippetSupport ?? false;
var commitCharactersRuleCache = new Dictionary <ImmutableArray <CharacterSetModificationRule>, ImmutableArray <string> >();
// Cache the completion list so we can avoid recomputation in the resolve handler
var resultId = await _completionListCache.UpdateCacheAsync(list, cancellationToken).ConfigureAwait(false);
// Feature flag to enable the return of TextEdits instead of InsertTexts (will increase payload size).
// Flag is defined in VisualStudio\Core\Def\PackageRegistration.pkgdef.
// We also check against the CompletionOption for test purposes only.
Contract.ThrowIfNull(context.Solution);
var featureFlagService = context.Solution.Workspace.Services.GetRequiredService <IExperimentationService>();
var returnTextEdits = featureFlagService.IsExperimentEnabled(WellKnownExperimentNames.LSPCompletion) ||
completionOptions.GetOption(CompletionOptions.ForceRoslynLSPCompletionExperiment, document.Project.Language);
SourceText?documentText = null;
TextSpan? defaultSpan = null;
LSP.Range?defaultRange = null;
if (returnTextEdits)
{
// We want to compute the document's text just once.
documentText = await document.GetTextAsync(cancellationToken).ConfigureAwait(false);
// We use the first item in the completion list as our comparison point for span
// and range for optimization when generating the TextEdits later on.
var completionChange = await completionService.GetChangeAsync(
document, list.Items.First(), cancellationToken : cancellationToken).ConfigureAwait(false);
// If possible, we want to compute the item's span and range just once.
// Individual items can override this range later.
defaultSpan = completionChange.TextChange.Span;
defaultRange = ProtocolConversions.TextSpanToRange(defaultSpan.Value, documentText);
}
var stringBuilder = new StringBuilder();
using var _ = ArrayBuilder <LSP.CompletionItem> .GetInstance(out var lspCompletionItems);
foreach (var item in list.Items)
{
var lspCompletionItem = await CreateLSPCompletionItemAsync(
request, document, item, resultId, lspVSClientCapability, completionTrigger, commitCharactersRuleCache,
completionService, context.ClientName, returnTextEdits, snippetsSupported, stringBuilder, documentText,
defaultSpan, defaultRange, cancellationToken).ConfigureAwait(false);
lspCompletionItems.Add(lspCompletionItem);
}
return(new LSP.VSCompletionList
{
Items = lspCompletionItems.ToArray(),
SuggestionMode = list.SuggestionModeItem != null,
});
// Local functions
bool IsValidTriggerCharacterForDocument(Document document, char triggerCharacter)
{
if (document.Project.Language == LanguageNames.CSharp)
{
return(_csharpTriggerCharacters.Contains(triggerCharacter));
}
else if (document.Project.Language == LanguageNames.VisualBasic)
{
return(_vbTriggerCharacters.Contains(triggerCharacter));
}
// Typescript still calls into this for completion.
// Since we don't know what their trigger characters are, just return true.
return(true);
}