public static void AnalyzeLogicalAndExpression(SyntaxNodeAnalysisContext context, INamedTypeSymbol expressionType)
{
var logicalAndExpression = (BinaryExpressionSyntax)context.Node;
if (logicalAndExpression.ContainsDiagnostics)
{
return;
}
ExpressionSyntax expression = SyntaxInfo.NullCheckExpressionInfo(logicalAndExpression.Left, allowedStyles: NullCheckStyles.NotEqualsToNull).Expression;
if (expression == null)
{
return;
}
if (context.SemanticModel
.GetTypeSymbol(expression, context.CancellationToken)?
.IsReferenceType != true)
{
return;
}
ExpressionSyntax right = logicalAndExpression.Right?.WalkDownParentheses();
if (right == null)
{
return;
}
if (!ValidateRightExpression(right, context.SemanticModel, context.CancellationToken))
{
return;
}
if (RefactoringUtility.ContainsOutArgumentWithLocal(right, context.SemanticModel, context.CancellationToken))
{
return;
}
ExpressionSyntax expression2 = FindExpressionThatCanBeConditionallyAccessed(expression, right);
if (expression2?.SpanContainsDirectives() != false)
{
return;
}
if (logicalAndExpression.IsInExpressionTree(expressionType, context.SemanticModel, context.CancellationToken))
{
return;
}
context.ReportDiagnostic(DiagnosticDescriptors.UseConditionalAccess, logicalAndExpression);
}
private static bool IsFixable(
ExpressionSyntax left,
ExpressionSyntax right,
SyntaxKind binaryExpressionKind,
SemanticModel semanticModel,
CancellationToken cancellationToken)
{
NullCheckStyles allowedStyles = (binaryExpressionKind == SyntaxKind.LogicalAndExpression)
? NullCheckStyles.NotEqualsToNull
: NullCheckStyles.EqualsToNull;
NullCheckExpressionInfo nullCheck = SyntaxInfo.NullCheckExpressionInfo(left, allowedStyles: allowedStyles);
ExpressionSyntax expression = nullCheck.Expression;
if (expression == null)
{
return(false);
}
ITypeSymbol typeSymbol = semanticModel.GetTypeSymbol(expression, cancellationToken);
if (typeSymbol == null)
{
return(false);
}
if (!typeSymbol.IsReferenceTypeOrNullableType())
{
return(false);
}
if (right == null)
{
return(false);
}
if (!ValidateRightExpression(right, binaryExpressionKind, semanticModel, cancellationToken))
{
return(false);
}
if (RefactoringUtility.ContainsOutArgumentWithLocal(right, semanticModel, cancellationToken))
{
return(false);
}
ExpressionSyntax expression2 = FindExpressionThatCanBeConditionallyAccessed(expression, right, isNullable: !typeSymbol.IsReferenceType);
return(expression2?.SpanContainsDirectives() == false);
}
private static void Analyze(
SyntaxNodeAnalysisContext context,
ConditionalExpressionInfo conditionalExpressionInfo,
ExpressionSyntax whenNull,
ExpressionSyntax whenNotNull,
SemanticModel semanticModel,
CancellationToken cancellationToken)
{
ITypeSymbol typeSymbol = semanticModel.GetTypeSymbol(whenNotNull, cancellationToken);
if (typeSymbol?.IsErrorType() == false &&
(typeSymbol.IsReferenceType || typeSymbol.IsValueType) &&
semanticModel.IsDefaultValue(typeSymbol, whenNull, cancellationToken) &&
!RefactoringUtility.ContainsOutArgumentWithLocal(whenNotNull, semanticModel, cancellationToken) &&
!conditionalExpressionInfo.ConditionalExpression.IsInExpressionTree(semanticModel, cancellationToken))
{
context.ReportDiagnostic(
DiagnosticDescriptors.UseConditionalAccessInsteadOfConditionalExpression,
conditionalExpressionInfo.ConditionalExpression);
}
}