public static ImmutableArray <TypeInferenceInfo> GetTypeInferenceInfo(
this ITypeInferenceService service,
SemanticModel semanticModel,
SyntaxNode expression,
CancellationToken cancellationToken
) =>
service.GetTypeInferenceInfo(
semanticModel,
expression,
nameOpt: null,
cancellationToken: cancellationToken
);
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);
}
}
// A lambda that is being typed may be parsed as a tuple without names
// For example, "(a, b" could be the start of either a tuple or lambda
// But "(a: b, c" cannot be a lambda
if (token.IsPossibleTupleElementNameContext(position) && token.Parent.IsKind(SyntaxKind.TupleExpression) &&
!((TupleExpressionSyntax)token.Parent).HasNames())
{
position = token.Parent.SpanStart;
}
// 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 inferredTypeInfo = typeInferrer.GetTypeInferenceInfo(semanticModel, position, cancellationToken: cancellationToken);
return(inferredTypeInfo.Any(type => GetDelegateType(type, semanticModel.Compilation).IsDelegateType()));
}
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;
}
}
// A lambda that is being typed may be parsed as a tuple without names
// For example, "(a, b" could be the start of either a tuple or lambda
// But "(a: b, c" cannot be a lambda
if (token.SyntaxTree.IsPossibleTupleContext(token, position) && token.Parent.IsKind(SyntaxKind.TupleExpression) &&
!((TupleExpressionSyntax)token.Parent).HasNames())
{
position = token.Parent.SpanStart;
}
// 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 inferredTypeInfo = typeInferrer.GetTypeInferenceInfo(semanticModel, position, cancellationToken: cancellationToken);
return inferredTypeInfo.Any(type => GetDelegateType(type, semanticModel.Compilation).IsDelegateType());
}
private static bool IsLambdaExpression(SemanticModel semanticModel, int position, SyntaxToken token, ITypeInferenceService typeInferrer, CancellationToken cancellationToken)
{
// Not after `new`
if (token.IsKind(SyntaxKind.NewKeyword) && token.Parent.IsKind(SyntaxKind.ObjectCreationExpression))
{
return(false);
}
// 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);
}
}
// A lambda that is being typed may be parsed as a tuple without names
// For example, "(a, b" could be the start of either a tuple or lambda
// But "(a: b, c" cannot be a lambda
if (token.SyntaxTree.IsPossibleTupleContext(token, position) &&
token.Parent.IsKind(SyntaxKind.TupleExpression, out TupleExpressionSyntax tupleExpression) &&
!tupleExpression.HasNames())
{
position = token.Parent.SpanStart;
}
// Walk up a single level to allow for typing the beginning of a lambda:
// new AssemblyLoadEventHandler(($$
if (token.Kind() == SyntaxKind.OpenParenToken &&
token.Parent.Kind() == SyntaxKind.ParenthesizedExpression)
{
position = token.Parent.SpanStart;
}
// WorkItem 834609: Automatic brace completion inserts the closing paren, making it
// like a cast.
if (token.Kind() == SyntaxKind.OpenParenToken &&
token.Parent.Kind() == SyntaxKind.CastExpression)
{
position = token.Parent.SpanStart;
}
// In the following situation, the type inferrer will infer Task to support target type preselection
// Action a = Task.$$
// We need to explicitly exclude invocation/member access from suggestion mode
var previousToken = token.GetPreviousTokenIfTouchingWord(position);
if (previousToken.IsKind(SyntaxKind.DotToken) &&
previousToken.Parent.IsKind(SyntaxKind.SimpleMemberAccessExpression))
{
return(false);
}
// async lambda:
// Goo(async($$
// Goo(async(p1, $$
if (token.IsKind(SyntaxKind.OpenParenToken, SyntaxKind.CommaToken) && token.Parent.IsKind(SyntaxKind.ArgumentList) &&
token.Parent.Parent is InvocationExpressionSyntax invocation &&
invocation.Expression is IdentifierNameSyntax identifier)
{
if (identifier.Identifier.IsKindOrHasMatchingText(SyntaxKind.AsyncKeyword))
{
return(true);
}
}
// 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 inferredTypeInfo = typeInferrer.GetTypeInferenceInfo(semanticModel, position, cancellationToken: cancellationToken);
return(inferredTypeInfo.Any(type => GetDelegateType(type, semanticModel.Compilation).IsDelegateType()));
}