IEnumerable <INamedTypeSymbol> FindNearestTupleConstructionWithInferrableType(SyntaxNode root, SemanticModel semanticModel, int position, SignatureHelpTriggerInfo triggerInfo,
ITypeInferenceService typeInferrer, ISyntaxFactsService syntaxFacts, CancellationToken cancellationToken, out ExpressionSyntax targetExpression)
{
// Walk upward through TupleExpressionSyntax/ParenthsizedExpressionSyntax looking for a
// place where we can infer a tuple type.
ParenthesizedExpressionSyntax parenthesizedExpression = null;
while (TryGetTupleExpression(triggerInfo.TriggerReason, root, position, syntaxFacts, cancellationToken, out var tupleExpression) ||
TryGetParenthesizedExpression(triggerInfo.TriggerReason, root, position, syntaxFacts, cancellationToken, out parenthesizedExpression))
{
targetExpression = (ExpressionSyntax)tupleExpression ?? parenthesizedExpression;
var inferredTypes = typeInferrer.InferTypes(semanticModel, targetExpression.SpanStart, cancellationToken);
var tupleTypes = inferredTypes.Where(t => t.IsTupleType).OfType <INamedTypeSymbol>().ToList();
if (tupleTypes.Any())
{
return(tupleTypes);
}
position = targetExpression.GetFirstToken().SpanStart;
}
targetExpression = null;
return(null);
}
public static INamedTypeSymbol InferDelegateType(
this ITypeInferenceService typeInferenceService,
SemanticModel semanticModel,
int position,
CancellationToken cancellationToken)
{
var types = typeInferenceService.InferTypes(semanticModel, position, cancellationToken);
return(GetFirstDelegateType(semanticModel, types));
}
public static INamedTypeSymbol InferDelegateType(
this ITypeInferenceService typeInferenceService,
SemanticModel semanticModel,
SyntaxNode expression,
CancellationToken cancellationToken)
{
var types = typeInferenceService.InferTypes(semanticModel, expression, cancellationToken);
var delegateTypes = types.Select(t => t.GetDelegateType(semanticModel.Compilation));
return(delegateTypes.WhereNotNull().FirstOrDefault());
}
public static ImmutableArray <ITypeSymbol> InferTypes(
this ITypeInferenceService service,
SemanticModel semanticModel,
int position,
CancellationToken cancellationToken
) =>
service.InferTypes(
semanticModel,
position,
nameOpt: null,
cancellationToken: cancellationToken
);
public static ITypeSymbol InferType(this ITypeInferenceService typeInferenceService,
SemanticModel semanticModel,
int position,
bool objectAsDefault,
CancellationToken cancellationToken)
{
var types = typeInferenceService.InferTypes(semanticModel, position, cancellationToken)
.WhereNotNull();
if (!types.Any())
{
return(objectAsDefault ? semanticModel.Compilation.ObjectType : null);
}
return(types.FirstOrDefault());
}
public static ITypeSymbol InferType(
this ITypeInferenceService typeInferenceService,
SemanticModel semanticModel,
int position,
bool objectAsDefault,
string nameOpt,
CancellationToken cancellationToken)
{
var types = typeInferenceService.InferTypes(semanticModel, position, nameOpt, cancellationToken);
if (types.Length == 0)
{
return(objectAsDefault ? semanticModel.Compilation.ObjectType : null);
}
return(types.FirstOrDefault());
}
public static ITypeSymbol?InferType(
this ITypeInferenceService typeInferenceService,
SemanticModel semanticModel,
SyntaxNode expression,
bool objectAsDefault,
string?name,
CancellationToken cancellationToken)
{
var types = typeInferenceService.InferTypes(semanticModel, expression, name, cancellationToken);
if (types.Length == 0)
{
return(objectAsDefault ? semanticModel.Compilation.ObjectType : null);
}
return(types.First());
}
private bool IsLambdaExpression(SemanticModel semanticModel, int position, SyntaxToken token, ITypeInferenceService typeInferrer, CancellationToken cancellationToken)
{
// Typing a generic type parameter, the tree might look like a binary expression around the < token.
// If we infer a delegate type here (because that's what on the other side of the binop),
// ignore it.
if (token.Kind() == SyntaxKind.LessThanToken && token.Parent is BinaryExpressionSyntax)
{
return(false);
}
// We might be in the arguments to a parenthesized lambda
if (token.Kind() == SyntaxKind.OpenParenToken || token.Kind() == SyntaxKind.CommaToken)
{
if (token.Parent != null && token.Parent is ParameterListSyntax)
{
return(token.Parent.Parent != null && token.Parent.Parent is ParenthesizedLambdaExpressionSyntax);
}
}
// Walk up a single level to allow for typing the beginning of a lambda:
// new AssemblyLoadEventHandler(($$
if (token.Kind() == SyntaxKind.OpenParenToken &&
token.Parent.Kind() == SyntaxKind.ParenthesizedExpression)
{
position = token.Parent.SpanStart;
}
// WorkItem 834609: Automatic brace completion inserts the closing paren, making it
// like a cast.
if (token.Kind() == SyntaxKind.OpenParenToken &&
token.Parent.Kind() == SyntaxKind.CastExpression)
{
position = token.Parent.SpanStart;
}
// If we're an argument to a function with multiple overloads,
// open the builder if any overload takes a delegate at our argument position
var inferredTypes = typeInferrer.InferTypes(semanticModel, position, cancellationToken: cancellationToken);
return(inferredTypes.Any(type => type.GetDelegateType(semanticModel.Compilation).IsDelegateType()));
}
IEnumerable<INamedTypeSymbol> FindNearestTupleConstructionWithInferrableType(SyntaxNode root, SemanticModel semanticModel, int position, SignatureHelpTriggerInfo triggerInfo,
ITypeInferenceService typeInferrer, ISyntaxFactsService syntaxFacts, CancellationToken cancellationToken, out ExpressionSyntax targetExpression)
{
// Walk upward through TupleExpressionSyntax/ParenthsizedExpressionSyntax looking for a
// place where we can infer a tuple type.
ParenthesizedExpressionSyntax parenthesizedExpression = null;
while (TryGetTupleExpression(triggerInfo.TriggerReason, root, position, syntaxFacts, cancellationToken, out var tupleExpression) ||
TryGetParenthesizedExpression(triggerInfo.TriggerReason, root, position, syntaxFacts, cancellationToken, out parenthesizedExpression))
{
targetExpression = (ExpressionSyntax)tupleExpression ?? parenthesizedExpression;
var inferredTypes = typeInferrer.InferTypes(semanticModel, targetExpression.SpanStart, cancellationToken);
var tupleTypes = inferredTypes.Where(t => t.IsTupleType).OfType<INamedTypeSymbol>().ToList();
if (tupleTypes.Any())
{
return tupleTypes;
}
position = targetExpression.GetFirstToken().SpanStart;
}
targetExpression = null;
return null;
}
private bool IsLambdaExpression(SemanticModel semanticModel, int position, SyntaxToken token, ITypeInferenceService typeInferrer, CancellationToken cancellationToken)
{
// Typing a generic type parameter, the tree might look like a binary expression around the < token.
// If we infer a delegate type here (because that's what on the other side of the binop),
// ignore it.
if (token.Kind() == SyntaxKind.LessThanToken && token.Parent is BinaryExpressionSyntax)
{
return false;
}
// We might be in the arguments to a parenthsized lambda
if (token.Kind() == SyntaxKind.OpenParenToken || token.Kind() == SyntaxKind.CommaToken)
{
if (token.Parent != null && token.Parent is ParameterListSyntax)
{
return token.Parent.Parent != null && token.Parent.Parent is ParenthesizedLambdaExpressionSyntax;
}
}
// Walk up a single level to allow for typing the beginning of a lambda:
// new AssemblyLoadEventHandler(($$
if (token.Kind() == SyntaxKind.OpenParenToken &&
token.Parent.Kind() == SyntaxKind.ParenthesizedExpression)
{
position = token.Parent.SpanStart;
}
// WorkItem 834609: Automatic brace completion inserts the closing paren, making it
// like a cast.
if (token.Kind() == SyntaxKind.OpenParenToken &&
token.Parent.Kind() == SyntaxKind.CastExpression)
{
position = token.Parent.SpanStart;
}
// If we're an argument to a function with multiple overloads,
// open the builder if any overload takes a delegate at our argument position
var inferredTypes = typeInferrer.InferTypes(semanticModel, position, cancellationToken: cancellationToken);
return inferredTypes.Any(type => type.GetDelegateType(semanticModel.Compilation).IsDelegateType());
}
public ImmutableArray <ITypeSymbol> InferTypes(SemanticModel semanticModel, int position, string?name, CancellationToken cancellationToken) => UnderlyingObject.InferTypes(semanticModel, position, name, cancellationToken);
