public override async Task <CheckResult> ShouldProvideCompletion(Document document, int position)
{
if (!document.SupportsSyntaxTree || !document.SupportsSemanticModel)
{
return(CheckResult.False());
}
var syntaxRoot = await document.GetSyntaxRootAsync();
if (syntaxRoot == null)
{
return(CheckResult.False());
}
var semanticModel = await document.GetSemanticModelAsync();
if (semanticModel == null)
{
return(CheckResult.False());
}
// Walk up and save literal expression if present (we can autocomplete literals).
var currentToken = syntaxRoot.FindToken(position - 1);
var currentNode = currentToken.Parent;
var literalExpression = RoslynUtils.WalkUpStringSyntaxOnce(ref currentNode, ref position);
// Walk up parenthesis because the inference service doesn't handle that.
currentToken = syntaxRoot.FindToken(position - 1);
currentNode = currentToken.Parent;
if (currentToken.Kind() != SyntaxKind.CloseParenToken)
{
RoslynUtils.WalkUpParenthesisExpressions(ref currentNode, ref position);
}
var inferredTypes = RoslynUtils.InferTypes(semanticModel, position, null, CancellationToken.None);
if (inferredTypes.Any(RoslynUtils.TypeIsNodePath))
{
return(CheckResult.True(literalExpression));
}
// Our own custom inference for NodePath
if (IsPathConstructorArgumentOfNodePath(syntaxRoot, semanticModel, currentNode, position))
{
return(CheckResult.True(literalExpression));
}
if (IsParenthesizedExprActuallyCastToNodePath(semanticModel, currentNode))
{
return(CheckResult.True(literalExpression));
}
return(CheckResult.False());
}
public override async Task <CheckResult> ShouldProvideCompletion(Document document, int position)
{
if (!document.SupportsSyntaxTree || !document.SupportsSemanticModel)
{
return(CheckResult.False());
}
var syntaxRoot = await document.GetSyntaxRootAsync();
if (syntaxRoot == null)
{
return(CheckResult.False());
}
var semanticModel = await document.GetSemanticModelAsync();
if (semanticModel == null)
{
return(CheckResult.False());
}
// Walk up and save literal expression if present (we can autocomplete literals).
var currentToken = syntaxRoot.FindToken(position - 1);
var currentNode = currentToken.Parent;
var literalExpression = RoslynUtils.WalkUpStringSyntaxOnce(ref currentNode, ref position);
// Walk up parenthesis because the inference service doesn't handle that.
currentToken = syntaxRoot.FindToken(position - 1);
currentNode = currentToken.Parent;
if (currentToken.Kind() != SyntaxKind.CloseParenToken)
{
RoslynUtils.WalkUpParenthesisExpressions(ref currentNode, ref position);
}
if (!(currentNode is ArgumentListSyntax argumentList && currentNode.Parent is InvocationExpressionSyntax invocation))
{
return(CheckResult.False());
}
var previousToken = syntaxRoot.FindToken(position - 1);
if (previousToken != argumentList.OpenParenToken && previousToken.Kind() != SyntaxKind.CommaToken)
{
return(CheckResult.False());
}
if (RoslynUtils.IsExpectedInvocationArgument(semanticModel, previousToken, invocation, argumentList, _expectedInvocations))
{
return(CheckResult.True(literalExpression));
}
return(CheckResult.False());
}
private static bool IsParenthesizedExprActuallyCastToNodePath(SemanticModel semanticModel, SyntaxNode currentNode)
{
// (NodePath)$$ which is detected as a parenthesized expression rather than a cast
if (!(currentNode is ParenthesizedExpressionSyntax parenthesizedExpression))
{
return(false);
}
if (!(parenthesizedExpression.Expression is IdentifierNameSyntax identifierNameSyntax))
{
return(false);
}
var typeInfo = semanticModel.GetTypeInfo(identifierNameSyntax).Type;
return(typeInfo != null && RoslynUtils.TypeIsNodePath(typeInfo));
}
private static bool IsPathConstructorArgumentOfNodePath(SyntaxNode syntaxRoot, SemanticModel semanticModel, SyntaxNode currentNode, int position)
{
// new NodePath($$) for NodePath(string) ctor
if (!(currentNode is ArgumentListSyntax argumentList && currentNode.Parent is ObjectCreationExpressionSyntax objectCreation))
{
return(false);
}
var previousToken = syntaxRoot.FindToken(position - 1);
if (previousToken != argumentList.OpenParenToken)
{
return(false);
}
if (argumentList.Arguments.Count > 1)
{
return(false); // The NodePath constructor we are looking for has only one parameter
}
int index = RoslynUtils.GetArgumentListIndex(argumentList, previousToken);
var info = semanticModel.GetSymbolInfo(objectCreation.Type);
if (!(info.Symbol is INamedTypeSymbol type))
{
return(false);
}
if (type.TypeKind == TypeKind.Delegate)
{
return(false);
}
if (!RoslynUtils.TypeIsNodePath(type))
{
return(false);
}
var constructors = type.InstanceConstructors.Where(m => m.Parameters.Length == 1);
var types = RoslynUtils.InferTypeInArgument(index, constructors.Select(m => m.Parameters), argumentOpt: null);
return(types.Any(RoslynUtils.TypeIsString));
}