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);
}
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 bool TryAnalyzeInvocationCondition(
SyntaxNodeAnalysisContext context,
ISyntaxFacts syntaxFacts,
IMethodSymbol?referenceEqualsMethodOpt,
TInvocationExpression invocation,
[NotNullWhen(true)] out SyntaxNode?conditionPartToCheck,
out bool isEquals)
{
conditionPartToCheck = null;
isEquals = true;
var expression = syntaxFacts.GetExpressionOfInvocationExpression(invocation);
var nameNode = syntaxFacts.IsIdentifierName(expression)
? expression
: syntaxFacts.IsSimpleMemberAccessExpression(expression)
? syntaxFacts.GetNameOfMemberAccessExpression(expression)
: null;
if (!syntaxFacts.IsIdentifierName(nameNode))
{
return(false);
}
syntaxFacts.GetNameAndArityOfSimpleName(nameNode, out var name, out _);
if (!syntaxFacts.StringComparer.Equals(name, nameof(ReferenceEquals)))
{
return(false);
}
var arguments = syntaxFacts.GetArgumentsOfInvocationExpression(invocation);
if (arguments.Count != 2)
{
return(false);
}
var conditionLeft = syntaxFacts.GetExpressionOfArgument(arguments[0]);
var conditionRight = syntaxFacts.GetExpressionOfArgument(arguments[1]);
if (conditionLeft == null || conditionRight == null)
{
return(false);
}
conditionPartToCheck = GetConditionPartToCheck(syntaxFacts, conditionLeft, conditionRight);
if (conditionPartToCheck == null)
{
return(false);
}
var semanticModel = context.SemanticModel;
var cancellationToken = context.CancellationToken;
var symbol = semanticModel.GetSymbolInfo(invocation, cancellationToken).Symbol;
return(referenceEqualsMethodOpt != null && referenceEqualsMethodOpt.Equals(symbol));
}
public static bool IsPossiblyDateAndTimeArgumentToken(
SyntaxToken token, ISyntaxFacts syntaxFacts,
[NotNullWhen(true)] out SyntaxNode?argumentNode,
[NotNullWhen(true)] out SyntaxNode?invocationExpression)
{
// Has to be a string literal passed to a method.
argumentNode = null;
invocationExpression = null;
if (!syntaxFacts.IsStringLiteral(token))
{
return(false);
}
if (!IsMethodArgument(token, syntaxFacts))
{
return(false);
}
if (!syntaxFacts.IsLiteralExpression(token.Parent))
{
return(false);
}
if (!syntaxFacts.IsArgument(token.Parent.Parent))
{
return(false);
}
var argumentList = token.Parent.Parent.Parent;
var invocationOrCreation = argumentList?.Parent;
if (!syntaxFacts.IsInvocationExpression(invocationOrCreation))
{
return(false);
}
var invokedExpression = syntaxFacts.GetExpressionOfInvocationExpression(invocationOrCreation);
var name = GetNameOfInvokedExpression(syntaxFacts, invokedExpression);
if (name != nameof(ToString) && name != nameof(System.DateTime.ParseExact) && name != nameof(System.DateTime.TryParseExact))
{
return(false);
}
// We have a string literal passed to a method called ToString/ParseExact/TryParseExact.
// Have to do a more expensive semantic check now.
argumentNode = token.Parent.Parent;
invocationExpression = invocationOrCreation;
return(true);
}