public static bool IsFixable(
SimpleMemberInvocationExpressionInfo invocationInfo,
SemanticModel semanticModel,
CancellationToken cancellationToken)
{
if (invocationInfo.Expression?.IsMissing != false)
{
return(false);
}
IMethodSymbol methodSymbol = semanticModel.GetReducedExtensionMethodInfo(invocationInfo.InvocationExpression, cancellationToken).Symbol;
if (methodSymbol == null)
{
return(false);
}
if (!SymbolUtility.IsLinqExtensionOfIEnumerableOfTWithoutParameters(methodSymbol, "First", semanticModel, allowImmutableArrayExtension: true))
{
return(false);
}
ITypeSymbol typeSymbol = semanticModel.GetTypeSymbol(invocationInfo.Expression, cancellationToken);
return(SymbolUtility.HasAccessibleIndexer(typeSymbol, semanticModel, invocationInfo.InvocationExpression.SpanStart));
}
public static void AnalyzeWhere(SyntaxNodeAnalysisContext context, SimpleMemberInvocationExpressionInfo invocationInfo)
{
SimpleMemberInvocationExpressionInfo invocationInfo2 = SyntaxInfo.SimpleMemberInvocationExpressionInfo(invocationInfo.Expression);
if (!invocationInfo2.Success)
{
return;
}
if (invocationInfo2.Arguments.Count != 1)
{
return;
}
if (invocationInfo2.NameText != "Where")
{
return;
}
InvocationExpressionSyntax invocation = invocationInfo.InvocationExpression;
SemanticModel semanticModel = context.SemanticModel;
CancellationToken cancellationToken = context.CancellationToken;
IMethodSymbol methodSymbol = semanticModel.GetExtensionMethodInfo(invocation, cancellationToken).Symbol;
if (methodSymbol == null)
{
return;
}
if (!SymbolUtility.IsLinqExtensionOfIEnumerableOfTWithoutParameters(methodSymbol, invocationInfo.NameText, semanticModel))
{
return;
}
IMethodSymbol methodSymbol2 = semanticModel.GetExtensionMethodInfo(invocationInfo2.InvocationExpression, cancellationToken).Symbol;
if (methodSymbol2 == null)
{
return;
}
if (!SymbolUtility.IsLinqWhere(methodSymbol2, semanticModel, allowImmutableArrayExtension: true))
{
return;
}
TextSpan span = TextSpan.FromBounds(invocationInfo2.Name.SpanStart, invocation.Span.End);
if (invocation.ContainsDirectives(span))
{
return;
}
context.ReportDiagnostic(
DiagnosticDescriptors.SimplifyLinqMethodChain,
Location.Create(invocation.SyntaxTree, span));
}
public static void Analyze(SyntaxNodeAnalysisContext context, SimpleMemberInvocationExpressionInfo invocationInfo)
{
InvocationExpressionSyntax invocationExpression = invocationInfo.InvocationExpression;
if (invocationExpression.IsParentKind(SyntaxKind.SimpleMemberAccessExpression))
{
return;
}
SemanticModel semanticModel = context.SemanticModel;
CancellationToken cancellationToken = context.CancellationToken;
IMethodSymbol methodSymbol = semanticModel.GetReducedExtensionMethodInfo(invocationExpression, cancellationToken).Symbol;
if (methodSymbol == null)
{
return;
}
if (!SymbolUtility.IsLinqExtensionOfIEnumerableOfTWithoutParameters(methodSymbol, "Any", semanticModel))
{
return;
}
string propertyName = CSharpUtility.GetCountOrLengthPropertyName(invocationInfo.Expression, semanticModel, cancellationToken);
if (propertyName == null)
{
return;
}
context.ReportDiagnostic(
DiagnosticDescriptors.UseCountOrLengthPropertyInsteadOfAnyMethod,
Location.Create(context.Node.SyntaxTree, TextSpan.FromBounds(invocationInfo.Name.SpanStart, invocationExpression.Span.End)),
ImmutableDictionary.CreateRange(new KeyValuePair <string, string>[] { new KeyValuePair <string, string>("PropertyName", propertyName) }),
propertyName);
}
public static void Analyze(SyntaxNodeAnalysisContext context, SimpleMemberInvocationExpressionInfo invocationInfo)
{
InvocationExpressionSyntax invocationExpression = invocationInfo.InvocationExpression;
SemanticModel semanticModel = context.SemanticModel;
CancellationToken cancellationToken = context.CancellationToken;
IMethodSymbol methodSymbol = semanticModel.GetReducedExtensionMethodInfo(invocationExpression, cancellationToken).Symbol;
if (methodSymbol == null)
{
return;
}
if (!SymbolUtility.IsLinqExtensionOfIEnumerableOfTWithoutParameters(methodSymbol, "Count", semanticModel))
{
return;
}
string propertyName = CSharpUtility.GetCountOrLengthPropertyName(invocationInfo.Expression, semanticModel, cancellationToken);
if (propertyName != null)
{
context.ReportDiagnostic(
DiagnosticDescriptors.UseCountOrLengthPropertyInsteadOfCountMethod,
Location.Create(context.Node.SyntaxTree, TextSpan.FromBounds(invocationInfo.Name.SpanStart, invocationExpression.Span.End)),
ImmutableDictionary.CreateRange(new KeyValuePair <string, string>[] { new KeyValuePair <string, string>("PropertyName", propertyName) }),
propertyName);
}
else
{
SyntaxNode parent = invocationExpression.Parent;
switch (parent.Kind())
{
case SyntaxKind.EqualsExpression:
case SyntaxKind.NotEqualsExpression:
{
var equalsExpression = (BinaryExpressionSyntax)parent;
if (equalsExpression.Left == invocationExpression)
{
if (equalsExpression.Right.IsNumericLiteralExpression("0"))
{
context.ReportDiagnostic(DiagnosticDescriptors.CallAnyInsteadOfCount, parent);
}
}
else if (equalsExpression.Left.IsNumericLiteralExpression("0"))
{
context.ReportDiagnostic(DiagnosticDescriptors.CallAnyInsteadOfCount, parent);
}
break;
}
case SyntaxKind.GreaterThanExpression:
{
var equalsExpression = (BinaryExpressionSyntax)parent;
if (equalsExpression.Left == invocationExpression)
{
if (equalsExpression.Right.IsNumericLiteralExpression("0"))
{
context.ReportDiagnostic(DiagnosticDescriptors.CallAnyInsteadOfCount, parent);
}
else
{
context.ReportDiagnostic(DiagnosticDescriptors.CallSkipAndAnyInsteadOfCount, parent);
}
}
else if (equalsExpression.Left.IsNumericLiteralExpression("1"))
{
context.ReportDiagnostic(DiagnosticDescriptors.CallAnyInsteadOfCount, parent);
}
else
{
context.ReportDiagnostic(DiagnosticDescriptors.CallSkipAndAnyInsteadOfCount, parent);
}
break;
}
case SyntaxKind.GreaterThanOrEqualExpression:
{
var equalsExpression = (BinaryExpressionSyntax)parent;
if (equalsExpression.Left == invocationExpression)
{
if (equalsExpression.Right.IsNumericLiteralExpression("1"))
{
context.ReportDiagnostic(DiagnosticDescriptors.CallAnyInsteadOfCount, parent);
}
else
{
context.ReportDiagnostic(DiagnosticDescriptors.CallSkipAndAnyInsteadOfCount, parent);
}
}
else if (equalsExpression.Left.IsNumericLiteralExpression("0"))
{
context.ReportDiagnostic(DiagnosticDescriptors.CallAnyInsteadOfCount, parent);
}
else
{
context.ReportDiagnostic(DiagnosticDescriptors.CallSkipAndAnyInsteadOfCount, parent);
}
break;
}
case SyntaxKind.LessThanExpression:
{
var equalsExpression = (BinaryExpressionSyntax)parent;
if (equalsExpression.Left == invocationExpression)
{
if (equalsExpression.Right.IsNumericLiteralExpression("1"))
{
context.ReportDiagnostic(DiagnosticDescriptors.CallAnyInsteadOfCount, parent);
}
else
{
context.ReportDiagnostic(DiagnosticDescriptors.CallSkipAndAnyInsteadOfCount, parent);
}
}
else if (equalsExpression.Left.IsNumericLiteralExpression("0"))
{
context.ReportDiagnostic(DiagnosticDescriptors.CallAnyInsteadOfCount, parent);
}
else
{
context.ReportDiagnostic(DiagnosticDescriptors.CallSkipAndAnyInsteadOfCount, parent);
}
break;
}
case SyntaxKind.LessThanOrEqualExpression:
{
var equalsExpression = (BinaryExpressionSyntax)parent;
if (equalsExpression.Left == invocationExpression)
{
if (equalsExpression.Right.IsNumericLiteralExpression("0"))
{
context.ReportDiagnostic(DiagnosticDescriptors.CallAnyInsteadOfCount, parent);
}
else
{
context.ReportDiagnostic(DiagnosticDescriptors.CallSkipAndAnyInsteadOfCount, parent);
}
}
else if (equalsExpression.Left.IsNumericLiteralExpression("1"))
{
context.ReportDiagnostic(DiagnosticDescriptors.CallAnyInsteadOfCount, parent);
}
else
{
context.ReportDiagnostic(DiagnosticDescriptors.CallSkipAndAnyInsteadOfCount, parent);
}
break;
}
}
}
}
private static void AnalyzeInvocationExpression(SyntaxNodeAnalysisContext context)
{
var invocationExpression = (InvocationExpressionSyntax)context.Node;
if (invocationExpression.ContainsDiagnostics)
{
return;
}
SimpleMemberInvocationExpressionInfo invocationInfo = SyntaxInfo.SimpleMemberInvocationExpressionInfo(invocationExpression);
if (!invocationInfo.Success)
{
return;
}
if (invocationInfo.Arguments.Count != 0)
{
return;
}
if (invocationInfo.NameText != "Count")
{
return;
}
SemanticModel semanticModel = context.SemanticModel;
CancellationToken cancellationToken = context.CancellationToken;
IMethodSymbol methodSymbol = semanticModel.GetReducedExtensionMethodInfo(invocationExpression, cancellationToken).Symbol;
if (methodSymbol == null)
{
return;
}
if (!SymbolUtility.IsLinqExtensionOfIEnumerableOfTWithoutParameters(methodSymbol, "Count"))
{
return;
}
SyntaxNode parent = invocationExpression.Parent;
switch (parent.Kind())
{
case SyntaxKind.GreaterThanExpression:
case SyntaxKind.LessThanOrEqualExpression:
{
var binaryExpression = (BinaryExpressionSyntax)parent;
if (binaryExpression.Left == invocationExpression)
{
if (!binaryExpression.Right.IsNumericLiteralExpression("0"))
{
ReportDiagnostic(parent);
}
}
else if (!binaryExpression.Left.IsNumericLiteralExpression("1"))
{
ReportDiagnostic(parent);
}
break;
}
case SyntaxKind.GreaterThanOrEqualExpression:
case SyntaxKind.LessThanExpression:
{
var binaryExpression = (BinaryExpressionSyntax)parent;
if (binaryExpression.Left == invocationExpression)
{
if (!binaryExpression.Right.IsNumericLiteralExpression("1"))
{
ReportDiagnostic(parent);
}
}
else if (!binaryExpression.Left.IsNumericLiteralExpression("0"))
{
ReportDiagnostic(parent);
}
break;
}
}
void ReportDiagnostic(SyntaxNode node)
{
context.ReportDiagnostic(DiagnosticDescriptors.CallSkipAndAnyInsteadOfCount, node);
}
}