protected override async Task <SignatureHelpItems> GetItemsWorkerAsync(Document document, int position, SignatureHelpTriggerInfo triggerInfo, CancellationToken cancellationToken)
{
var root = await document.GetSyntaxRootAsync(cancellationToken).ConfigureAwait(false);
if (!TryGetConstructorInitializer(root, position, document.GetLanguageService <ISyntaxFactsService>(), triggerInfo.TriggerReason, cancellationToken, out var constructorInitializer))
{
return(null);
}
var semanticModel = await document.GetSemanticModelAsync(cancellationToken).ConfigureAwait(false);
var within = semanticModel.GetEnclosingNamedType(position, cancellationToken);
if (within == null)
{
return(null);
}
if (within.TypeKind != TypeKind.Struct && within.TypeKind != TypeKind.Class)
{
return(null);
}
var type = constructorInitializer.Kind() == SyntaxKind.BaseConstructorInitializer
? within.BaseType
: within;
if (type == null)
{
return(null);
}
var currentConstructor = semanticModel.GetDeclaredSymbol(constructorInitializer.Parent);
var symbolDisplayService = document.GetLanguageService <ISymbolDisplayService>();
var accessibleConstructors = type.InstanceConstructors
.WhereAsArray(c => c.IsAccessibleWithin(within) && !c.Equals(currentConstructor))
.WhereAsArray(c => c.IsEditorBrowsable(document.ShouldHideAdvancedMembers(), semanticModel.Compilation))
.Sort(symbolDisplayService, semanticModel, constructorInitializer.SpanStart);
if (!accessibleConstructors.Any())
{
return(null);
}
var anonymousTypeDisplayService = document.GetLanguageService <IAnonymousTypeDisplayService>();
var documentationCommentFormattingService = document.GetLanguageService <IDocumentationCommentFormattingService>();
var textSpan = SignatureHelpUtilities.GetSignatureHelpSpan(constructorInitializer.ArgumentList);
var syntaxFacts = document.GetLanguageService <ISyntaxFactsService>();
var symbolInfo = semanticModel.GetSymbolInfo(constructorInitializer, cancellationToken);
var selectedItem = TryGetSelectedIndex(accessibleConstructors, symbolInfo);
return(CreateSignatureHelpItems(accessibleConstructors.SelectAsArray(c =>
Convert(c, constructorInitializer.ArgumentList.OpenParenToken, semanticModel, symbolDisplayService, anonymousTypeDisplayService, documentationCommentFormattingService, cancellationToken)).ToList(),
textSpan, GetCurrentArgumentState(root, position, syntaxFacts, textSpan, cancellationToken), selectedItem));
}
public override SignatureHelpState GetCurrentArgumentState(SyntaxNode root, int position, ISyntaxFactsService syntaxFacts, TextSpan currentSpan, CancellationToken cancellationToken)
{
if (TryGetAttributeExpression(root, position, syntaxFacts, SignatureHelpTriggerReason.InvokeSignatureHelpCommand, cancellationToken, out var expression) &&
currentSpan.Start == SignatureHelpUtilities.GetSignatureHelpSpan(expression.ArgumentList).Start)
{
return(SignatureHelpUtilities.GetSignatureHelpState(expression.ArgumentList, position));
}
return(null);
}
protected override async Task <SignatureHelpItems> GetItemsWorkerAsync(Document document, int position, SignatureHelpTriggerInfo triggerInfo, CancellationToken cancellationToken)
{
var root = await document.GetSyntaxRootAsync(cancellationToken).ConfigureAwait(false);
if (!TryGetAttributeExpression(root, position, document.GetLanguageService <ISyntaxFactsService>(), triggerInfo.TriggerReason, cancellationToken, out var attribute))
{
return(null);
}
var semanticModel = await document.GetSemanticModelForNodeAsync(attribute, cancellationToken).ConfigureAwait(false);
var attributeType = semanticModel.GetTypeInfo(attribute, cancellationToken).Type as INamedTypeSymbol;
if (attributeType == null)
{
return(null);
}
var within = semanticModel.GetEnclosingNamedTypeOrAssembly(position, cancellationToken);
if (within == null)
{
return(null);
}
var symbolDisplayService = document.GetLanguageService <ISymbolDisplayService>();
var accessibleConstructors = attributeType.InstanceConstructors
.WhereAsArray(c => c.IsAccessibleWithin(within))
.FilterToVisibleAndBrowsableSymbols(document.ShouldHideAdvancedMembers(), semanticModel.Compilation)
.Sort(symbolDisplayService, semanticModel, attribute.SpanStart);
if (!accessibleConstructors.Any())
{
return(null);
}
var anonymousTypeDisplayService = document.GetLanguageService <IAnonymousTypeDisplayService>();
var documentationCommentFormatter = document.GetLanguageService <IDocumentationCommentFormattingService>();
var textSpan = SignatureHelpUtilities.GetSignatureHelpSpan(attribute.ArgumentList);
var syntaxFacts = document.GetLanguageService <ISyntaxFactsService>();
var symbolInfo = semanticModel.GetSymbolInfo(attribute, cancellationToken);
var selectedItem = TryGetSelectedIndex(accessibleConstructors, symbolInfo);
return(CreateSignatureHelpItems(accessibleConstructors.Select(c =>
Convert(c, within, attribute, semanticModel, symbolDisplayService, anonymousTypeDisplayService, documentationCommentFormatter, cancellationToken)).ToList(),
textSpan, GetCurrentArgumentState(root, position, syntaxFacts, textSpan, cancellationToken), selectedItem));
}
public override SignatureHelpState GetCurrentArgumentState(SyntaxNode root, int position, ISyntaxFactsService syntaxFacts, TextSpan currentSpan, CancellationToken cancellationToken)
{
if (!TryGetElementAccessExpression(
root,
position,
syntaxFacts,
SignatureHelpTriggerReason.InvokeSignatureHelpCommand,
cancellationToken,
out var expression,
out var openBracket) ||
currentSpan.Start != expression.SpanStart)
{
return(null);
}
// If the user is actively typing, it's likely that we're in a broken state and the
// syntax tree will be incorrect. Because of this we need to synthesize a new
// bracketed argument list so we can correctly map the cursor to the current argument
// and then we need to account for this and offset the position check accordingly.
int offset;
BracketedArgumentListSyntax argumentList;
var newBracketedArgumentList = SyntaxFactory.ParseBracketedArgumentList(openBracket.Parent.ToString());
if (expression.Parent is ConditionalAccessExpressionSyntax)
{
// The typed code looks like: <expression>?[
var conditional = (ConditionalAccessExpressionSyntax)expression.Parent;
var elementBinding = SyntaxFactory.ElementBindingExpression(newBracketedArgumentList);
var conditionalAccessExpression = SyntaxFactory.ConditionalAccessExpression(expression, elementBinding);
offset = expression.SpanStart - conditionalAccessExpression.SpanStart;
argumentList = ((ElementBindingExpressionSyntax)conditionalAccessExpression.WhenNotNull).ArgumentList;
}
else
{
// The typed code looks like:
// <expression>[
// or
// <identifier>?[
ElementAccessExpressionSyntax elementAccessExpression = SyntaxFactory.ElementAccessExpression(expression, newBracketedArgumentList);
offset = expression.SpanStart - elementAccessExpression.SpanStart;
argumentList = elementAccessExpression.ArgumentList;
}
position -= offset;
return(SignatureHelpUtilities.GetSignatureHelpState(argumentList, position));
}
public override SignatureHelpState GetCurrentArgumentState(SyntaxNode root, int position, ISyntaxFactsService syntaxFacts, TextSpan currentSpan, CancellationToken cancellationToken)
{
if (!TryGetGenericIdentifier(root, position, syntaxFacts, SignatureHelpTriggerReason.InvokeSignatureHelpCommand, cancellationToken,
out var genericIdentifier, out var lessThanToken))
{
return(null);
}
if (genericIdentifier.TryParseGenericName(cancellationToken, out var genericName))
{
// Because we synthesized the generic name, it will have an index starting at 0
// instead of at the actual position it's at in the text. Because of this, we need to
// offset the position we are checking accordingly.
var offset = genericIdentifier.SpanStart - genericName.SpanStart;
position -= offset;
return(SignatureHelpUtilities.GetSignatureHelpState(genericName.TypeArgumentList, position));
}
return(null);
}
protected override async Task <SignatureHelpItems> GetItemsWorkerAsync(Document document, int position, SignatureHelpTriggerInfo triggerInfo, CancellationToken cancellationToken)
{
var root = await document.GetSyntaxRootAsync(cancellationToken).ConfigureAwait(false);
if (!TryGetObjectCreationExpression(root, position, document.GetLanguageService <ISyntaxFactsService>(), triggerInfo.TriggerReason, cancellationToken, out var objectCreationExpression))
{
return(null);
}
var semanticModel = await document.GetSemanticModelForNodeAsync(objectCreationExpression, cancellationToken).ConfigureAwait(false);
var type = semanticModel.GetTypeInfo(objectCreationExpression, cancellationToken).Type as INamedTypeSymbol;
if (type == null)
{
return(null);
}
var within = semanticModel.GetEnclosingNamedType(position, cancellationToken);
if (within == null)
{
return(null);
}
var symbolDisplayService = document.GetLanguageService <ISymbolDisplayService>();
var anonymousTypeDisplayService = document.GetLanguageService <IAnonymousTypeDisplayService>();
var documentationCommentFormattingService = document.GetLanguageService <IDocumentationCommentFormattingService>();
var textSpan = SignatureHelpUtilities.GetSignatureHelpSpan(objectCreationExpression.ArgumentList);
var syntaxFacts = document.GetLanguageService <ISyntaxFactsService>();
var(items, selectedItem) = type.TypeKind == TypeKind.Delegate
? GetDelegateTypeConstructors(objectCreationExpression, semanticModel, symbolDisplayService, anonymousTypeDisplayService, type, within, cancellationToken)
: GetNormalTypeConstructors(document, objectCreationExpression, semanticModel, symbolDisplayService, anonymousTypeDisplayService, documentationCommentFormattingService, type, within, cancellationToken);
return(CreateSignatureHelpItems(items, textSpan,
GetCurrentArgumentState(root, position, syntaxFacts, textSpan, cancellationToken), selectedItem));
}
protected override async Task <SignatureHelpItems> GetItemsWorkerAsync(Document document, int position, SignatureHelpTriggerInfo triggerInfo, CancellationToken cancellationToken)
{
var root = await document.GetSyntaxRootAsync(cancellationToken).ConfigureAwait(false);
if (!TryGetInvocationExpression(root, position, document.GetLanguageService <ISyntaxFactsService>(), triggerInfo.TriggerReason, cancellationToken, out var invocationExpression))
{
return(null);
}
var semanticModel = await document.GetSemanticModelForNodeAsync(invocationExpression, cancellationToken).ConfigureAwait(false);
var within = semanticModel.GetEnclosingNamedTypeOrAssembly(position, cancellationToken);
if (within == null)
{
return(null);
}
// get the regular signature help items
var symbolDisplayService = document.GetLanguageService <ISymbolDisplayService>();
var methodGroup = semanticModel.GetMemberGroup(invocationExpression.Expression, cancellationToken)
.OfType <IMethodSymbol>()
.ToImmutableArray()
.FilterToVisibleAndBrowsableSymbols(document.ShouldHideAdvancedMembers(), semanticModel.Compilation);
// try to bind to the actual method
var symbolInfo = semanticModel.GetSymbolInfo(invocationExpression, cancellationToken);
// if the symbol could be bound, replace that item in the symbol list
if (symbolInfo.Symbol is IMethodSymbol matchedMethodSymbol && matchedMethodSymbol.IsGenericMethod)
{
methodGroup = methodGroup.SelectAsArray(m => matchedMethodSymbol.OriginalDefinition == m ? matchedMethodSymbol : m);
}
methodGroup = methodGroup.Sort(
symbolDisplayService, semanticModel, invocationExpression.SpanStart);
var expressionType = semanticModel.GetTypeInfo(invocationExpression.Expression, cancellationToken).Type as INamedTypeSymbol;
var anonymousTypeDisplayService = document.GetLanguageService <IAnonymousTypeDisplayService>();
var documentationCommentFormattingService = document.GetLanguageService <IDocumentationCommentFormattingService>();
var textSpan = SignatureHelpUtilities.GetSignatureHelpSpan(invocationExpression.ArgumentList);
var syntaxFacts = document.GetLanguageService <ISyntaxFactsService>();
if (methodGroup.Any())
{
var(items, selectedItem) =
GetMethodGroupItemsAndSelection(invocationExpression, semanticModel, symbolDisplayService, anonymousTypeDisplayService, documentationCommentFormattingService, within, methodGroup, symbolInfo, cancellationToken);
return(CreateSignatureHelpItems(
items,
textSpan,
GetCurrentArgumentState(root, position, syntaxFacts, textSpan, cancellationToken),
selectedItem));
}
else if (expressionType != null && expressionType.TypeKind == TypeKind.Delegate)
{
var items = GetDelegateInvokeItems(invocationExpression, semanticModel, symbolDisplayService, anonymousTypeDisplayService,
documentationCommentFormattingService, within, expressionType, out var selectedItem, cancellationToken);
return(CreateSignatureHelpItems(items, textSpan, GetCurrentArgumentState(root, position, syntaxFacts, textSpan, cancellationToken), selectedItem));
}
else
{
return(null);
}
}
private bool IsTriggerToken(SyntaxToken token)
{
return(SignatureHelpUtilities.IsTriggerParenOrComma <InvocationExpressionSyntax>(token, IsTriggerCharacter));
}
private bool IsTriggerToken(SyntaxToken token)
{
return(SignatureHelpUtilities.IsTriggerParenOrComma <ConstructorInitializerSyntax>(token, IsTriggerCharacter));
}
internal static TextSpan GetTextSpan(SyntaxNode expression, SyntaxToken openBracket)
{
Contract.ThrowIfFalse(openBracket.Parent is BracketedArgumentListSyntax &&
(openBracket.Parent.Parent is ElementAccessExpressionSyntax || openBracket.Parent.Parent is ElementBindingExpressionSyntax));
return(SignatureHelpUtilities.GetSignatureHelpSpan((BracketedArgumentListSyntax)openBracket.Parent));
}
protected virtual TextSpan GetTextSpan(SyntaxToken genericIdentifier, SyntaxToken lessThanToken)
{
Contract.ThrowIfFalse(lessThanToken.Parent is TypeArgumentListSyntax && lessThanToken.Parent.Parent is GenericNameSyntax);
return(SignatureHelpUtilities.GetSignatureHelpSpan(((GenericNameSyntax)lessThanToken.Parent.Parent).TypeArgumentList));
}