private static TExpressionSyntax?Unwrap(ISyntaxFacts syntaxFacts, TExpressionSyntax node)
{
node = (TExpressionSyntax)syntaxFacts.WalkDownParentheses(node);
if (node is TInvocationExpressionSyntax invocation)
{
return((TExpressionSyntax)syntaxFacts.GetExpressionOfInvocationExpression(invocation));
}
if (syntaxFacts.IsSimpleMemberAccessExpression(node))
{
return((TExpressionSyntax?)syntaxFacts.GetExpressionOfMemberAccessExpression(node));
}
if (node is TConditionalAccessExpressionSyntax conditionalAccess)
{
return((TExpressionSyntax)syntaxFacts.GetExpressionOfConditionalAccessExpression(conditionalAccess));
}
if (node is TElementAccessExpressionSyntax elementAccess)
{
return((TExpressionSyntax?)syntaxFacts.GetExpressionOfElementAccessExpression(elementAccess));
}
return(null);
}
private static SyntaxNode?Unwrap(ISyntaxFacts syntaxFacts, SyntaxNode node)
{
node = syntaxFacts.WalkDownParentheses(node);
if (node is TInvocationExpression invocation)
{
return(syntaxFacts.GetExpressionOfInvocationExpression(invocation));
}
if (node is TMemberAccessExpression memberAccess)
{
return(syntaxFacts.GetExpressionOfMemberAccessExpression(memberAccess));
}
if (node is TConditionalAccessExpression conditionalAccess)
{
return(syntaxFacts.GetExpressionOfConditionalAccessExpression(conditionalAccess));
}
if (node is TElementAccessExpression elementAccess)
{
return(syntaxFacts.GetExpressionOfElementAccessExpression(elementAccess));
}
return(null);
}
protected override bool IsViableExtensionMethod(
IMethodSymbol method,
SyntaxNode expression,
SemanticModel semanticModel,
ISyntaxFacts syntaxFacts,
CancellationToken cancellationToken
)
{
var leftExpression =
syntaxFacts.GetExpressionOfMemberAccessExpression(expression)
?? syntaxFacts.GetTargetOfMemberBinding(expression);
if (leftExpression == null)
{
if (expression.IsKind(SyntaxKind.CollectionInitializerExpression))
{
leftExpression = expression.GetAncestor <ObjectCreationExpressionSyntax>();
}
else
{
return(false);
}
}
var semanticInfo = semanticModel.GetTypeInfo(leftExpression, cancellationToken);
var leftExpressionType = semanticInfo.Type;
return(IsViableExtensionMethod(method, leftExpressionType));
}
