public sealed override async Task RegisterCodeFixesAsync(CodeFixContext context)
{
if (!Settings.IsCodeFixEnabled(CodeFixIdentifiers.AddComparisonWithBooleanLiteral) &&
!Settings.IsCodeFixEnabled(CodeFixIdentifiers.CreateSingletonArray) &&
!Settings.IsCodeFixEnabled(CodeFixIdentifiers.UseUncheckedExpression) &&
!Settings.IsCodeFixEnabled(CodeFixIdentifiers.RemoveConstModifier) &&
!Settings.IsCodeFixEnabled(CodeFixIdentifiers.ReplaceNullLiteralExpressionWithDefaultValue) &&
!Settings.IsCodeFixEnabled(CodeFixIdentifiers.UseCoalesceExpression) &&
!Settings.IsCodeFixEnabled(CodeFixIdentifiers.RemoveConditionThatIsAlwaysEqualToTrueOrFalse) &&
!Settings.IsCodeFixEnabled(CodeFixIdentifiers.IntroduceLocalVariable) &&
!Settings.IsCodeFixEnabled(CodeFixIdentifiers.IntroduceField) &&
!Settings.IsCodeFixEnabled(CodeFixIdentifiers.ReplaceStringLiteralWithCharacterLiteral) &&
!Settings.IsCodeFixEnabled(CodeFixIdentifiers.UseYieldReturnInsteadOfReturn) &&
!Settings.IsCodeFixEnabled(CodeFixIdentifiers.ChangeMemberTypeAccordingToReturnExpression) &&
!Settings.IsCodeFixEnabled(CodeFixIdentifiers.AddArgumentList))
{
return;
}
SyntaxNode root = await context.GetSyntaxRootAsync().ConfigureAwait(false);
if (!TryFindNode(root, context.Span, out ExpressionSyntax expression))
{
return;
}
foreach (Diagnostic diagnostic in context.Diagnostics)
{
switch (diagnostic.Id)
{
case CompilerDiagnosticIdentifiers.CannotImplicitlyConvertTypeExplicitConversionExists:
{
SemanticModel semanticModel = await context.GetSemanticModelAsync().ConfigureAwait(false);
TypeInfo typeInfo = semanticModel.GetTypeInfo(expression, context.CancellationToken);
ITypeSymbol type = typeInfo.Type;
ITypeSymbol convertedType = typeInfo.ConvertedType;
if ((type is INamedTypeSymbol namedType) &&
namedType.ConstructedFrom.SpecialType == SpecialType.System_Nullable_T)
{
if (convertedType?.IsBoolean() == true ||
AddComparisonWithBooleanLiteralRefactoring.IsCondition(expression))
{
if (Settings.IsCodeFixEnabled(CodeFixIdentifiers.AddComparisonWithBooleanLiteral))
{
CodeAction codeAction = CodeAction.Create(
AddComparisonWithBooleanLiteralRefactoring.GetTitle(expression),
cancellationToken => AddComparisonWithBooleanLiteralRefactoring.RefactorAsync(context.Document, expression, cancellationToken),
GetEquivalenceKey(diagnostic, CodeFixIdentifiers.AddComparisonWithBooleanLiteral));
context.RegisterCodeFix(codeAction, diagnostic);
}
}
else if (namedType.TypeArguments[0].Equals(convertedType))
{
if (Settings.IsCodeFixEnabled(CodeFixIdentifiers.UseCoalesceExpression))
{
CodeAction codeAction = CodeAction.Create(
"Use coalesce expression",
cancellationToken =>
{
ExpressionSyntax defaultValue = convertedType.ToDefaultValueSyntax(semanticModel, expression.SpanStart);
ExpressionSyntax newNode = CoalesceExpression(expression.WithoutTrivia(), defaultValue)
.WithTriviaFrom(expression)
.Parenthesize()
.WithFormatterAnnotation();
return(context.Document.ReplaceNodeAsync(expression, newNode, cancellationToken));
},
GetEquivalenceKey(diagnostic, CodeFixIdentifiers.UseCoalesceExpression));
context.RegisterCodeFix(codeAction, diagnostic);
}
}
}
if (Settings.IsCodeFixEnabled(CodeFixIdentifiers.ChangeMemberTypeAccordingToReturnExpression) &&
expression.IsParentKind(SyntaxKind.ReturnStatement, SyntaxKind.YieldReturnStatement))
{
ChangeMemberTypeRefactoring.ComputeCodeFix(context, diagnostic, expression, semanticModel);
}
if (Settings.IsCodeFixEnabled(CodeFixIdentifiers.AddCastExpression))
{
CodeFixRegistrator.AddCastExpression(context, diagnostic, expression, convertedType, semanticModel);
}
if (Settings.IsCodeFixEnabled(CodeFixIdentifiers.CreateSingletonArray) &&
type?.IsErrorType() == false &&
!type.Equals(convertedType) &&
(convertedType is IArrayTypeSymbol arrayType) &&
semanticModel.IsImplicitConversion(expression, arrayType.ElementType))
{
CodeAction codeAction = CodeAction.Create(
"Create singleton array",
cancellationToken => CreateSingletonArrayRefactoring.RefactorAsync(context.Document, expression, arrayType.ElementType, semanticModel, cancellationToken),
GetEquivalenceKey(diagnostic, CodeFixIdentifiers.CreateSingletonArray));
context.RegisterCodeFix(codeAction, diagnostic);
}
break;
}
case CompilerDiagnosticIdentifiers.ConstantValueCannotBeConverted:
{
if (!Settings.IsCodeFixEnabled(CodeFixIdentifiers.UseUncheckedExpression))
{
break;
}
CodeAction codeAction = CodeAction.Create(
"Use 'unchecked'",
cancellationToken =>
{
CheckedExpressionSyntax newNode = CSharpFactory.UncheckedExpression(expression.WithoutTrivia());
newNode = newNode.WithTriviaFrom(expression);
return(context.Document.ReplaceNodeAsync(expression, newNode, cancellationToken));
},
GetEquivalenceKey(diagnostic));
context.RegisterCodeFix(codeAction, diagnostic);
break;
}
case CompilerDiagnosticIdentifiers.ExpressionBeingAssignedMustBeConstant:
{
if (!Settings.IsCodeFixEnabled(CodeFixIdentifiers.RemoveConstModifier))
{
break;
}
LocalDeclarationStatementSyntax localDeclarationStatement = GetLocalDeclarationStatement(expression);
if (localDeclarationStatement == null)
{
break;
}
SyntaxTokenList modifiers = localDeclarationStatement.Modifiers;
if (!modifiers.Contains(SyntaxKind.ConstKeyword))
{
break;
}
ModifiersCodeFixRegistrator.RemoveModifier(context, diagnostic, localDeclarationStatement, SyntaxKind.ConstKeyword);
break;
}
case CompilerDiagnosticIdentifiers.CannotConvertNullToTypeBecauseItIsNonNullableValueType:
case CompilerDiagnosticIdentifiers.CannotConvertNullToTypeParameterBecauseItCouldBeNonNullableValueType:
{
if (!Settings.IsCodeFixEnabled(CodeFixIdentifiers.ReplaceNullLiteralExpressionWithDefaultValue))
{
break;
}
SemanticModel semanticModel = await context.GetSemanticModelAsync().ConfigureAwait(false);
CodeFixRegistrator.ReplaceNullWithDefaultValue(context, diagnostic, expression, semanticModel);
break;
}
case CompilerDiagnosticIdentifiers.ResultOfExpressionIsAlwaysConstantSinceValueIsNeverEqualToNull:
{
if (!Settings.IsCodeFixEnabled(CodeFixIdentifiers.RemoveConditionThatIsAlwaysEqualToTrueOrFalse))
{
break;
}
NullCheckExpressionInfo nullCheck = SyntaxInfo.NullCheckExpressionInfo(expression, allowedKinds: NullCheckKind.ComparisonToNull);
if (!nullCheck.Success)
{
break;
}
CodeAction codeAction = CodeAction.Create(
"Remove condition",
cancellationToken =>
{
cancellationToken.ThrowIfCancellationRequested();
SyntaxNode newRoot = RemoveHelper.RemoveCondition(root, expression, nullCheck.Kind == NullCheckKind.NotEqualsToNull);
return(Task.FromResult(context.Document.WithSyntaxRoot(newRoot)));
},
GetEquivalenceKey(diagnostic));
context.RegisterCodeFix(codeAction, diagnostic);
break;
}
case CompilerDiagnosticIdentifiers.OnlyAssignmentCallIncrementDecrementAndNewObjectExpressionsCanBeUsedAsStatement:
{
SemanticModel semanticModel = await context.GetSemanticModelAsync().ConfigureAwait(false);
if (expression.Parent is ArrowExpressionClauseSyntax arrowExpresssionClause)
{
if (!Settings.IsCodeFixEnabled(CodeFixIdentifiers.ChangeMemberTypeAccordingToReturnExpression))
{
break;
}
ChangeMemberTypeRefactoring.ComputeCodeFix(context, diagnostic, expression, semanticModel);
}
else if (expression.Parent is ExpressionStatementSyntax expressionStatement)
{
if (Settings.IsCodeFixEnabled(CodeFixIdentifiers.AddArgumentList) &&
expression.IsKind(
SyntaxKind.IdentifierName,
SyntaxKind.SimpleMemberAccessExpression))
{
SyntaxNode invocationExpression = SyntaxFactory.InvocationExpression(expression);
if (semanticModel.GetSpeculativeMethodSymbol(expression.SpanStart, invocationExpression) != null)
{
CodeAction codeAction = CodeAction.Create(
"Add argument list",
cancellationToken => context.Document.ReplaceNodeAsync(expression, invocationExpression, cancellationToken),
GetEquivalenceKey(diagnostic, CodeFixIdentifiers.AddArgumentList));
context.RegisterCodeFix(codeAction, diagnostic);
}
}
if (Settings.IsAnyCodeFixEnabled(
CodeFixIdentifiers.IntroduceLocalVariable,
CodeFixIdentifiers.IntroduceField))
{
if (semanticModel.GetSymbol(expression, context.CancellationToken)?.IsErrorType() != false)
{
break;
}
ITypeSymbol typeSymbol = semanticModel.GetTypeSymbol(expression, context.CancellationToken);
if (typeSymbol?.IsErrorType() != false)
{
break;
}
if (Settings.IsCodeFixEnabled(CodeFixIdentifiers.IntroduceLocalVariable) &&
!expressionStatement.IsEmbedded())
{
bool addAwait = typeSymbol.IsConstructedFromTaskOfT(semanticModel) &&
semanticModel.GetEnclosingSymbol(expressionStatement.SpanStart, context.CancellationToken).IsAsyncMethod();
CodeAction codeAction = CodeAction.Create(
IntroduceLocalVariableRefactoring.GetTitle(expression),
cancellationToken => IntroduceLocalVariableRefactoring.RefactorAsync(context.Document, expressionStatement, typeSymbol, addAwait, semanticModel, cancellationToken),
GetEquivalenceKey(diagnostic, CodeFixIdentifiers.IntroduceLocalVariable));
context.RegisterCodeFix(codeAction, diagnostic);
}
if (Settings.IsCodeFixEnabled(CodeFixIdentifiers.IntroduceField))
{
CodeAction codeAction = CodeAction.Create(
$"Introduce field for '{expression}'",
cancellationToken => IntroduceFieldRefactoring.RefactorAsync(context.Document, expressionStatement, typeSymbol, semanticModel, cancellationToken),
GetEquivalenceKey(diagnostic, CodeFixIdentifiers.IntroduceField));
context.RegisterCodeFix(codeAction, diagnostic);
}
}
}
break;
}
case CompilerDiagnosticIdentifiers.CannotImplicitlyConvertType:
{
if (Settings.IsCodeFixEnabled(CodeFixIdentifiers.ChangeMemberTypeAccordingToReturnExpression) &&
expression.IsParentKind(SyntaxKind.ReturnStatement, SyntaxKind.YieldReturnStatement))
{
SemanticModel semanticModel = await context.GetSemanticModelAsync().ConfigureAwait(false);
ChangeMemberTypeRefactoring.ComputeCodeFix(context, diagnostic, expression, semanticModel);
break;
}
if (Settings.IsCodeFixEnabled(CodeFixIdentifiers.ReplaceStringLiteralWithCharacterLiteral) &&
expression?.IsKind(SyntaxKind.StringLiteralExpression) == true)
{
var literalExpression = (LiteralExpressionSyntax)expression;
if (literalExpression.Token.ValueText.Length == 1)
{
SemanticModel semanticModel = await context.GetSemanticModelAsync().ConfigureAwait(false);
if (semanticModel.GetTypeInfo(expression, context.CancellationToken).ConvertedType?.IsChar() == true)
{
CodeAction codeAction = CodeAction.Create(
"Replace string literal with character literal",
cancellationToken => ReplaceStringLiteralWithCharacterLiteralRefactoring.RefactorAsync(context.Document, literalExpression, cancellationToken),
GetEquivalenceKey(diagnostic, CodeFixIdentifiers.ReplaceStringLiteralWithCharacterLiteral));
context.RegisterCodeFix(codeAction, diagnostic);
}
}
}
if (Settings.IsCodeFixEnabled(CodeFixIdentifiers.UseYieldReturnInsteadOfReturn) &&
expression.IsParentKind(SyntaxKind.ReturnStatement))
{
var returnStatement = (ReturnStatementSyntax)expression.Parent;
SemanticModel semanticModel = await context.GetSemanticModelAsync().ConfigureAwait(false);
ISymbol containingSymbol = semanticModel.GetEnclosingSymbol(returnStatement.SpanStart, context.CancellationToken);
if (containingSymbol?.IsKind(SymbolKind.Method) == true &&
((IMethodSymbol)containingSymbol).ReturnType?.IsIEnumerableOrConstructedFromIEnumerableOfT() == true)
{
CodeAction codeAction = CodeAction.Create(
"Use yield return instead of return",
cancellationToken => UseYieldReturnInsteadOfReturnRefactoring.RefactorAsync(context.Document, returnStatement, SyntaxKind.YieldReturnStatement, semanticModel, cancellationToken),
GetEquivalenceKey(diagnostic, CodeFixIdentifiers.UseYieldReturnInsteadOfReturn));
context.RegisterCodeFix(codeAction, diagnostic);
}
}
break;
}
}
}
}
public static void AnalyzeUsingStatement(SyntaxNodeAnalysisContext context)
{
var usingStatement = (UsingStatementSyntax)context.Node;
VariableDeclaratorSyntax declarator = usingStatement.Declaration?.Variables.SingleOrDefault(shouldThrow: false);
if (declarator == null)
{
return;
}
if (!(usingStatement.Statement?.SingleNonBlockStatementOrDefault() is WhileStatementSyntax whileStatement))
{
return;
}
SimpleMemberInvocationExpressionInfo invocationInfo = SyntaxInfo.SimpleMemberInvocationExpressionInfo(whileStatement.Condition);
if (!invocationInfo.Success)
{
return;
}
if (invocationInfo.Arguments.Any())
{
return;
}
if (!string.Equals(invocationInfo.NameText, WellKnownMemberNames.MoveNextMethodName, StringComparison.Ordinal))
{
return;
}
if (!string.Equals((invocationInfo.Expression as IdentifierNameSyntax)?.Identifier.ValueText, declarator.Identifier.ValueText, StringComparison.Ordinal))
{
return;
}
SimpleMemberInvocationExpressionInfo invocationInfo2 = SyntaxInfo.SimpleMemberInvocationExpressionInfo(declarator.Initializer.Value);
if (!invocationInfo2.Success)
{
return;
}
if (invocationInfo2.Arguments.Any())
{
return;
}
if (!string.Equals(invocationInfo2.NameText, WellKnownMemberNames.GetEnumeratorMethodName, StringComparison.Ordinal))
{
return;
}
UnnecessaryUsageOfEnumeratorWalker walker = UnnecessaryUsageOfEnumeratorWalker.GetInstance();
walker.SetValues(declarator, context.SemanticModel, context.CancellationToken);
walker.Visit(whileStatement.Statement);
bool?isFixable = walker.IsFixable;
UnnecessaryUsageOfEnumeratorWalker.Free(walker);
if (isFixable == true)
{
DiagnosticHelpers.ReportDiagnostic(context, DiagnosticDescriptors.UnnecessaryUsageOfEnumerator, usingStatement.UsingKeyword);
}
}
public static void AnalyzeIfStatement(SyntaxNodeAnalysisContext context, INamedTypeSymbol expressionOfTSymbol)
{
var ifStatement = (IfStatementSyntax)context.Node;
if (!ifStatement.IsSimpleIf())
{
return;
}
if (ifStatement.ContainsDiagnostics)
{
return;
}
if (ifStatement.SpanContainsDirectives())
{
return;
}
NullCheckExpressionInfo nullCheck = SyntaxInfo.NullCheckExpressionInfo(ifStatement.Condition, allowedStyles: NullCheckStyles.NotEqualsToNull);
ExpressionSyntax expression = nullCheck.Expression;
if (expression == null)
{
return;
}
SimpleMemberInvocationStatementInfo invocationInfo = SyntaxInfo.SimpleMemberInvocationStatementInfo(ifStatement.SingleNonBlockStatementOrDefault());
ExpressionSyntax expression2 = invocationInfo.Expression;
if (expression2 == null)
{
return;
}
ITypeSymbol typeSymbol = context.SemanticModel.GetTypeSymbol(expression);
if (typeSymbol == null)
{
return;
}
if (typeSymbol.IsNullableType())
{
if (!expression2.IsKind(SyntaxKind.SimpleMemberAccessExpression))
{
return;
}
var memberAccess = (MemberAccessExpressionSyntax)expression2;
if (!(memberAccess.Name is IdentifierNameSyntax identifierName))
{
return;
}
if (!string.Equals(identifierName.Identifier.ValueText, "Value", StringComparison.Ordinal))
{
return;
}
expression2 = memberAccess.Expression;
}
if (!CSharpFactory.AreEquivalent(expression, expression2))
{
return;
}
if (ifStatement.IsInExpressionTree(expressionOfTSymbol, context.SemanticModel, context.CancellationToken))
{
return;
}
context.ReportDiagnostic(DiagnosticDescriptors.UseConditionalAccess, ifStatement);
}
public static async Task <Document> RefactorAsync(
Document document,
ArgumentSyntax argument,
MemberInvocationExpressionInfo invocationInfo,
CancellationToken cancellationToken)
{
SemanticModel semanticModel = await document.GetSemanticModelAsync(cancellationToken).ConfigureAwait(false);
InvocationExpressionSyntax invocation = invocationInfo.InvocationExpression;
InvocationExpressionSyntax newInvocation = null;
bool isAppendLine = string.Equals(invocationInfo.NameText, "AppendLine", StringComparison.Ordinal);
ExpressionSyntax expression = argument.Expression;
switch (expression.Kind())
{
case SyntaxKind.InterpolatedStringExpression:
{
newInvocation = ConvertInterpolatedStringExpressionToInvocationExpression((InterpolatedStringExpressionSyntax)argument.Expression, invocationInfo, semanticModel);
break;
}
case SyntaxKind.AddExpression:
{
ImmutableArray <ExpressionSyntax> expressions = SyntaxInfo.BinaryExpressionChainInfo((BinaryExpressionSyntax)expression).Expressions;
newInvocation = invocation
.ReplaceNode(invocationInfo.Name, IdentifierName("Append").WithTriviaFrom(invocationInfo.Name))
.WithArgumentList(invocation.ArgumentList.WithArguments(SingletonSeparatedList(Argument(expressions[0]))).WithoutTrailingTrivia());
for (int i = 1; i < expressions.Length; i++)
{
ExpressionSyntax argumentExpression = expressions[i];
string methodName;
if (i == expressions.Length - 1 &&
isAppendLine &&
semanticModel
.GetTypeInfo(argumentExpression, cancellationToken)
.ConvertedType?
.SpecialType == SpecialType.System_String)
{
methodName = "AppendLine";
}
else
{
methodName = "Append";
}
newInvocation = SimpleMemberInvocationExpression(
newInvocation,
IdentifierName(methodName),
ArgumentList(Argument(argumentExpression)));
if (i == expressions.Length - 1 &&
isAppendLine &&
!string.Equals(methodName, "AppendLine", StringComparison.Ordinal))
{
newInvocation = SimpleMemberInvocationExpression(
newInvocation,
IdentifierName("AppendLine"),
ArgumentList());
}
}
break;
}
default:
{
newInvocation = CreateInvocationExpression(
(InvocationExpressionSyntax)expression,
invocation);
if (isAppendLine)
{
newInvocation = SimpleMemberInvocationExpression(newInvocation, IdentifierName("AppendLine"), ArgumentList());
}
break;
}
}
newInvocation = newInvocation
.WithTriviaFrom(invocation)
.WithFormatterAnnotation();
return(await document.ReplaceNodeAsync(invocation, newInvocation, cancellationToken).ConfigureAwait(false));
}
private static SingleLocalDeclarationStatementInfo GetLocalInfo(StatementSyntax statement)
{
return((statement.IsKind(SyntaxKind.LocalDeclarationStatement))
? SyntaxInfo.SingleLocalDeclarationStatementInfo((LocalDeclarationStatementSyntax)statement)
: default);
public static void AnalyzeIfStatement(SyntaxNodeAnalysisContext context)
{
var ifStatement = (IfStatementSyntax)context.Node;
if (ifStatement.IsSimpleIf())
{
return;
}
StatementListInfo statementsInfo = SyntaxInfo.StatementListInfo(ifStatement);
if (!statementsInfo.Success)
{
return;
}
ReturnStatementSyntax returnStatement = FindReturnStatementBelow(statementsInfo.Statements, ifStatement);
ExpressionSyntax expression = returnStatement?.Expression;
if (expression == null)
{
return;
}
if (ifStatement.SpanOrTrailingTriviaContainsDirectives())
{
return;
}
if (returnStatement.SpanOrLeadingTriviaContainsDirectives())
{
return;
}
SemanticModel semanticModel = context.SemanticModel;
CancellationToken cancellationToken = context.CancellationToken;
ISymbol symbol = semanticModel.GetSymbol(expression, cancellationToken);
if (symbol == null)
{
return;
}
if (!IsLocalDeclaredInScopeOrNonRefOrOutParameterOfEnclosingSymbol(symbol, statementsInfo.Parent, semanticModel, cancellationToken))
{
return;
}
foreach (IfStatementOrElseClause ifOrElse in ifStatement.AsCascade())
{
StatementSyntax statement = ifOrElse.Statement;
if (statement.IsKind(SyntaxKind.Block))
{
statement = ((BlockSyntax)statement).Statements.LastOrDefault();
}
if (!IsSymbolAssignedInStatement(symbol, statement, semanticModel, cancellationToken))
{
return;
}
}
DiagnosticHelpers.ReportDiagnostic(context, DiagnosticDescriptors.UseReturnInsteadOfAssignment, ifStatement);
}
private static InterpolatedStringExpressionSyntax ReplaceInterpolationWithStringLiteralInnerText(
SeparatedSyntaxList <ArgumentSyntax> arguments,
InterpolatedStringExpressionSyntax interpolatedString,
string text)
{
StringBuilder sb = StringBuilderCache.GetInstance();
int pos = 0;
SyntaxList <InterpolatedStringContentSyntax> contents = interpolatedString.Contents;
for (int i = 0; i < contents.Count; i++)
{
if (contents[i].Kind() != SyntaxKind.Interpolation)
{
continue;
}
var interpolation = (InterpolationSyntax)contents[i];
ExpressionSyntax expression = interpolation.Expression;
if (expression?.Kind() != SyntaxKind.NumericLiteralExpression)
{
continue;
}
var index = (int)((LiteralExpressionSyntax)expression).Token.Value;
if (index < 0)
{
continue;
}
if (index >= arguments.Count)
{
continue;
}
ExpressionSyntax argumentExpression = arguments[index + 1].Expression;
StringLiteralExpressionInfo stringLiteral = SyntaxInfo.StringLiteralExpressionInfo(argumentExpression);
if (!stringLiteral.Success)
{
continue;
}
sb.Append(text, pos, interpolation.SpanStart - pos);
int startIndex = sb.Length;
sb.Append(stringLiteral.InnerText);
sb.Replace("{", "{{", startIndex);
sb.Replace("}", "}}", startIndex);
pos = interpolation.Span.End;
}
sb.Append(text, pos, text.Length - pos);
return((InterpolatedStringExpressionSyntax)ParseExpression(StringBuilderCache.GetStringAndFree(sb)));
}
public static async Task <Document> RefactorAsync(
Document document,
PropertyDeclarationSyntax propertyDeclaration,
bool prefixIdentifierWithUnderscore = true,
CancellationToken cancellationToken = default)
{
string fieldName = StringUtility.ToCamelCase(
propertyDeclaration.Identifier.ValueText,
prefixWithUnderscore: prefixIdentifierWithUnderscore);
SemanticModel semanticModel = await document.GetSemanticModelAsync(cancellationToken).ConfigureAwait(false);
fieldName = NameGenerator.Default.EnsureUniqueName(
fieldName,
semanticModel,
propertyDeclaration.SpanStart);
FieldDeclarationSyntax fieldDeclaration = FieldDeclaration(
(propertyDeclaration.Modifiers.Contains(SyntaxKind.StaticKeyword)) ? Modifiers.Private_Static() : Modifiers.Private(),
propertyDeclaration.Type,
fieldName,
propertyDeclaration.Initializer).WithFormatterAnnotation();
IPropertySymbol propertySymbol = semanticModel.GetDeclaredSymbol(propertyDeclaration, cancellationToken);
PropertyDeclarationSyntax newPropertyDeclaration = ExpandAccessors(document, propertyDeclaration, propertySymbol, fieldName, semanticModel)
.WithModifiers(propertyDeclaration.Modifiers.Replace(SyntaxKind.AbstractKeyword, SyntaxKind.VirtualKeyword))
.WithTriviaFrom(propertyDeclaration)
.WithFormatterAnnotation();
MemberDeclarationListInfo membersInfo = SyntaxInfo.MemberDeclarationListInfo(propertyDeclaration.Parent);
SyntaxList <MemberDeclarationSyntax> members = membersInfo.Members;
int propertyIndex = membersInfo.IndexOf(propertyDeclaration);
AccessorListSyntax accessorList = propertyDeclaration.AccessorList;
if (accessorList?.Getter()?.IsAutoImplemented() == true &&
accessorList.Setter() == null)
{
ImmutableArray <SyntaxNode> nodes = await SyntaxFinder.FindReferencesAsync(propertySymbol, document, cancellationToken : cancellationToken).ConfigureAwait(false);
IdentifierNameSyntax newNode = IdentifierName(fieldName);
SyntaxNode newParent = membersInfo.Parent.ReplaceNodes(nodes, (node, _) =>
{
if (node.IsParentKind(SyntaxKind.SimpleMemberAccessExpression) &&
((MemberAccessExpressionSyntax)node.Parent).Expression.IsKind(SyntaxKind.BaseExpression))
{
return(node);
}
return(newNode.WithTriviaFrom(node));
});
MemberDeclarationListInfo newMembersInfo = SyntaxInfo.MemberDeclarationListInfo(newParent);
members = newMembersInfo.Members;
}
SyntaxList <MemberDeclarationSyntax> newMembers = members.ReplaceAt(propertyIndex, newPropertyDeclaration);
newMembers = MemberDeclarationInserter.Default.Insert(newMembers, fieldDeclaration);
return(await document.ReplaceMembersAsync(membersInfo, newMembers, cancellationToken).ConfigureAwait(false));
}
private static void AnalyzeConditionalExpression(SyntaxNodeAnalysisContext context)
{
if (context.Node.SpanContainsDirectives())
{
return;
}
var conditionalExpression = (ConditionalExpressionSyntax)context.Node;
ConditionalExpressionInfo conditionalExpressionInfo = SyntaxInfo.ConditionalExpressionInfo(conditionalExpression);
if (!conditionalExpressionInfo.Success)
{
return;
}
SemanticModel semanticModel = context.SemanticModel;
CancellationToken cancellationToken = context.CancellationToken;
NullCheckExpressionInfo nullCheck = SyntaxInfo.NullCheckExpressionInfo(conditionalExpressionInfo.Condition, semanticModel: semanticModel, cancellationToken: cancellationToken);
if (!nullCheck.Success)
{
return;
}
ExpressionSyntax whenNotNull = (nullCheck.IsCheckingNotNull) ? conditionalExpressionInfo.WhenTrue : conditionalExpressionInfo.WhenFalse;
ExpressionSyntax whenNull = (nullCheck.IsCheckingNotNull) ? conditionalExpressionInfo.WhenFalse : conditionalExpressionInfo.WhenTrue;
if (CSharpFactory.AreEquivalent(nullCheck.Expression, whenNotNull))
{
if (!context.IsAnalyzerSuppressed(DiagnosticDescriptors.UseCoalesceExpressionInsteadOfConditionalExpression) &&
semanticModel
.GetTypeSymbol(nullCheck.Expression, cancellationToken)?
.IsReferenceTypeOrNullableType() == true)
{
DiagnosticHelpers.ReportDiagnostic(context,
DiagnosticDescriptors.UseCoalesceExpressionInsteadOfConditionalExpression,
conditionalExpression);
}
}
else if (whenNotNull.IsKind(
SyntaxKind.SimpleMemberAccessExpression,
SyntaxKind.ElementAccessExpression,
SyntaxKind.ConditionalAccessExpression,
SyntaxKind.InvocationExpression))
{
ExpressionSyntax expression = UseConditionalAccessAnalyzer.FindExpressionThatCanBeConditionallyAccessed(
nullCheck.Expression,
whenNotNull,
semanticModel,
cancellationToken);
if (expression == null)
{
return;
}
ITypeSymbol typeSymbol = semanticModel.GetTypeSymbol(nullCheck.Expression, cancellationToken);
if (typeSymbol == null)
{
return;
}
if (typeSymbol.IsReferenceType)
{
Analyze(context, conditionalExpressionInfo, whenNull, whenNotNull, semanticModel, cancellationToken);
}
else if (typeSymbol.IsNullableType())
{
if (expression.IsParentKind(SyntaxKind.SimpleMemberAccessExpression))
{
var memberAccessExpression = (MemberAccessExpressionSyntax)expression.Parent;
if (!memberAccessExpression.IsParentKind(SyntaxKind.InvocationExpression) &&
(memberAccessExpression.Name as IdentifierNameSyntax)?.Identifier.ValueText == "Value")
{
if (memberAccessExpression == whenNotNull)
{
if (!context.IsAnalyzerSuppressed(DiagnosticDescriptors.UseCoalesceExpressionInsteadOfConditionalExpression))
{
DiagnosticHelpers.ReportDiagnostic(
context,
DiagnosticDescriptors.UseCoalesceExpressionInsteadOfConditionalExpression,
conditionalExpression);
}
}
else
{
Analyze(context, conditionalExpressionInfo, whenNull, whenNotNull, semanticModel, cancellationToken);
}
}
}
}
}
else if (!context.IsAnalyzerSuppressed(DiagnosticDescriptors.UseConditionalAccessInsteadOfConditionalExpression) &&
((CSharpCompilation)context.Compilation).LanguageVersion >= LanguageVersion.CSharp6 &&
whenNotNull.IsKind(SyntaxKind.CastExpression) &&
whenNull.IsKind(SyntaxKind.NullLiteralExpression, SyntaxKind.DefaultLiteralExpression))
{
var castExpression = (CastExpressionSyntax)whenNotNull;
if (castExpression.Type.IsKind(SyntaxKind.NullableType) &&
castExpression.Expression.IsKind(SyntaxKind.InvocationExpression, SyntaxKind.SimpleMemberAccessExpression, SyntaxKind.ElementAccessExpression))
{
ExpressionSyntax expression = UseConditionalAccessAnalyzer.FindExpressionThatCanBeConditionallyAccessed(
nullCheck.Expression,
castExpression.Expression,
isNullable: true,
semanticModel,
cancellationToken);
if (expression != null)
{
ITypeSymbol typeSymbol = semanticModel.GetTypeSymbol(nullCheck.Expression, cancellationToken);
if (typeSymbol?.OriginalDefinition.SpecialType == SpecialType.System_Nullable_T)
{
DiagnosticHelpers.ReportDiagnostic(context,
DiagnosticDescriptors.UseConditionalAccessInsteadOfConditionalExpression,
conditionalExpression);
}
}
}
}
}
public static void AnalyzeMethodDeclaration(SyntaxNodeAnalysisContext context, INamedTypeSymbol eventArgsSymbol)
{
var methodDeclaration = (MethodDeclarationSyntax)context.Node;
if (methodDeclaration.ContainsDiagnostics)
{
return;
}
if (methodDeclaration.IsParentKind(SyntaxKind.InterfaceDeclaration))
{
return;
}
if (methodDeclaration.Modifiers.ContainsAny(SyntaxKind.AbstractKeyword, SyntaxKind.VirtualKeyword, SyntaxKind.OverrideKeyword))
{
return;
}
ParameterInfo parameterInfo = SyntaxInfo.ParameterInfo(methodDeclaration);
if (!parameterInfo.Success)
{
return;
}
if (ContainsOnlyThrowNewExpression(parameterInfo.Body))
{
return;
}
IMethodSymbol methodSymbol = context.SemanticModel.GetDeclaredSymbol(methodDeclaration, context.CancellationToken);
if (methodSymbol == null)
{
return;
}
if (SymbolUtility.IsEventHandlerMethod(methodSymbol, eventArgsSymbol))
{
return;
}
if (!methodSymbol.ExplicitInterfaceImplementations.IsDefaultOrEmpty)
{
return;
}
if (methodSymbol.ImplementsInterfaceMember(allInterfaces: true))
{
return;
}
Dictionary <string, NodeSymbolInfo> unusedNodes = FindUnusedNodes(context, parameterInfo);
if (unusedNodes.Count == 0)
{
return;
}
if (IsReferencedAsMethodGroup(context, methodDeclaration))
{
return;
}
foreach (KeyValuePair <string, NodeSymbolInfo> kvp in unusedNodes)
{
ReportDiagnostic(context, kvp.Value.Node);
}
unusedNodes.Clear();
}
public static async Task ComputeRefactoringAsync(
RefactoringContext context,
PropertyDeclarationSyntax property)
{
AccessorDeclarationSyntax setter = property.Setter();
if (setter == null)
{
return;
}
ExpressionSyntax expression = GetExpression();
if (expression == null)
{
return;
}
SimpleAssignmentExpressionInfo simpleAssignment = SyntaxInfo.SimpleAssignmentExpressionInfo(expression);
if (!simpleAssignment.Success)
{
return;
}
if (!simpleAssignment.Left.IsKind(SyntaxKind.IdentifierName))
{
return;
}
if (!(simpleAssignment.Right is IdentifierNameSyntax identifierName))
{
return;
}
if (identifierName.Identifier.ValueText != "value")
{
return;
}
SemanticModel semanticModel = await context.GetSemanticModelAsync().ConfigureAwait(false);
INamedTypeSymbol containingType = semanticModel
.GetDeclaredSymbol(property, context.CancellationToken)?
.ContainingType;
if (containingType == null)
{
return;
}
if (!containingType.Implements(MetadataNames.System_ComponentModel_INotifyPropertyChanged, allInterfaces: true))
{
return;
}
IMethodSymbol methodSymbol = SymbolUtility.FindMethodThatRaisePropertyChanged(containingType, expression.SpanStart, semanticModel);
if (methodSymbol == null)
{
return;
}
Document document = context.Document;
context.RegisterRefactoring(
"Notify when property change",
ct => RefactorAsync(document, property, methodSymbol.Name, ct),
RefactoringIdentifiers.NotifyWhenPropertyChange);
ExpressionSyntax GetExpression()
{
BlockSyntax body = setter.Body;
if (body != null)
{
if (body.Statements.SingleOrDefault(shouldThrow: false) is ExpressionStatementSyntax expressionStatement)
{
return(expressionStatement.Expression);
}
}
else
{
return(setter.ExpressionBody?.Expression);
}
return(null);
}
}
public static async Task <Document> InvertIfAsync(
Document document,
IfStatementSyntax ifStatement,
bool recursive = false,
CancellationToken cancellationToken = default)
{
cancellationToken.ThrowIfCancellationRequested();
StatementSyntax statement = ifStatement.Statement;
StatementListInfo statementsInfo = SyntaxInfo.StatementListInfo(ifStatement);
SyntaxList <StatementSyntax> statements = statementsInfo.Statements;
InvertIfAnalysis analysis = InvertIfAnalysis.Create(ifStatement, statement);
int ifStatementIndex = statements.IndexOf(ifStatement);
StatementSyntax lastStatement = analysis.LastStatement;
int lastStatementIndex = statements.IndexOf(lastStatement);
bool isLastStatementRedundant = IsLastStatementRedundant();
bool shouldUseElseClause = !CSharpFacts.IsJumpStatement(lastStatement.Kind());
SemanticModel semanticModel = await document.GetSemanticModelAsync(cancellationToken).ConfigureAwait(false);
SyntaxList <StatementSyntax> newStatements = statements;
if (!recursive)
{
Refactor();
}
else
{
IfStatementSyntax lastIfStatement;
InvertIfAnalysis a = analysis.AnalyzeNextStatement();
do
{
lastIfStatement = a.IfStatement;
a = a.AnalyzeNextStatement();
} while (a.Success);
int firstLastStatementIndex = lastStatementIndex;
int index = statements.IndexOf(lastIfStatement);
int firstIndex = ifStatementIndex;
while (index >= firstIndex)
{
ifStatementIndex = index;
ifStatement = (IfStatementSyntax)statements[ifStatementIndex];
statement = ifStatement.Statement;
Refactor();
lastStatementIndex = firstLastStatementIndex + newStatements.Count - statements.Count;
lastStatement = (statement is BlockSyntax block) ? block.Statements.Last() : statement;
index--;
}
}
return(await document.ReplaceStatementsAsync(statementsInfo, newStatements, cancellationToken).ConfigureAwait(false));
void Refactor()
{
cancellationToken.ThrowIfCancellationRequested();
SyntaxList <StatementSyntax> nextStatements = newStatements
.Skip(ifStatementIndex + 1)
.Take(lastStatementIndex - ifStatementIndex)
.ToSyntaxList()
.TrimTrivia();
BlockSyntax newStatement;
SyntaxList <StatementSyntax> newNextStatements;
if (statement is BlockSyntax block)
{
newStatement = block.WithStatements(nextStatements);
newNextStatements = block.Statements;
}
else
{
newStatement = Block(nextStatements);
newNextStatements = SingletonList(statement);
}
if (isLastStatementRedundant)
{
newNextStatements = newNextStatements.RemoveAt(newNextStatements.Count - 1);
}
ElseClauseSyntax elseClause = null;
if (newNextStatements.Any() &&
shouldUseElseClause)
{
elseClause = ElseClause(Block(newNextStatements));
newNextStatements = default;
}
IfStatementSyntax newIfStatement = ifStatement.Update(
ifKeyword: ifStatement.IfKeyword,
openParenToken: ifStatement.OpenParenToken,
condition: SyntaxInverter.LogicallyInvert(ifStatement.Condition, semanticModel, cancellationToken),
closeParenToken: ifStatement.CloseParenToken,
statement: newStatement,
@else: elseClause);
newIfStatement = newIfStatement.WithFormatterAnnotation();
SyntaxList <StatementSyntax> newNodes = newNextStatements.Insert(0, newIfStatement);
newStatements = newStatements.ReplaceRange(ifStatementIndex, lastStatementIndex - ifStatementIndex + 1, newNodes);
}
bool IsLastStatementRedundant()
{
StatementSyntax jumpStatement = analysis.JumpStatement;
switch (jumpStatement.Kind())
{
case SyntaxKind.ReturnStatement:
{
if (((ReturnStatementSyntax)jumpStatement).Expression == null &&
RemoveRedundantStatementAnalysis.IsFixable(lastStatement, SyntaxKind.ReturnStatement))
{
return(true);
}
break;
}
case SyntaxKind.ContinueStatement:
{
if (RemoveRedundantStatementAnalysis.IsFixable(lastStatement, SyntaxKind.ContinueStatement))
{
return(true);
}
break;
}
}
return(false);
}
}
public static async Task <Document> RefactorAsync(
Document document,
ConditionalExpressionSyntax conditionalExpression,
CancellationToken cancellationToken)
{
SemanticModel semanticModel = await document.GetSemanticModelAsync().ConfigureAwait(false);
ConditionalExpressionInfo conditionalExpressionInfo = SyntaxInfo.ConditionalExpressionInfo(conditionalExpression);
NullCheckExpressionInfo nullCheck = SyntaxInfo.NullCheckExpressionInfo(conditionalExpressionInfo.Condition, semanticModel: semanticModel, cancellationToken: cancellationToken);
ExpressionSyntax whenNotNull = (nullCheck.IsCheckingNotNull) ? conditionalExpressionInfo.WhenTrue : conditionalExpressionInfo.WhenFalse;
ExpressionSyntax whenNull = (nullCheck.IsCheckingNotNull) ? conditionalExpressionInfo.WhenFalse : conditionalExpressionInfo.WhenTrue;
ExpressionSyntax expression = (whenNotNull.IsKind(SyntaxKind.CastExpression))
? UseConditionalAccessAnalyzer.FindExpressionThatCanBeConditionallyAccessed(nullCheck.Expression, ((CastExpressionSyntax)whenNotNull).Expression)
: UseConditionalAccessAnalyzer.FindExpressionThatCanBeConditionallyAccessed(nullCheck.Expression, whenNotNull);
bool coalesce = false;
ExpressionSyntax newNode = null;
if (CSharpFactory.AreEquivalent(nullCheck.Expression, whenNotNull))
{
//RCS1084 UseCoalesceExpressionInsteadOfConditionalExpression
newNode = nullCheck.Expression;
coalesce = true;
}
else if (semanticModel
.GetTypeSymbol(nullCheck.Expression, cancellationToken)
.IsNullableType())
{
if (expression.IsParentKind(SyntaxKind.SimpleMemberAccessExpression))
{
var memberAccessExpression = (MemberAccessExpressionSyntax)expression.Parent;
if (!memberAccessExpression.IsParentKind(SyntaxKind.InvocationExpression) &&
(memberAccessExpression.Name as IdentifierNameSyntax)?.Identifier.ValueText == "Value")
{
if (memberAccessExpression == whenNotNull)
{
//RCS1084 UseCoalesceExpressionInsteadOfConditionalExpression
newNode = nullCheck.Expression;
coalesce = true;
}
else
{
newNode = ParseExpression($"{expression}?{whenNotNull.ToString().Substring(memberAccessExpression.Span.End - whenNotNull.SpanStart)}");
}
}
}
}
if (newNode == null)
{
newNode = ParseExpression(whenNotNull.ToString().Insert(expression.Span.End - whenNotNull.SpanStart, "?"));
}
if (coalesce || !semanticModel.GetTypeSymbol(whenNotNull, cancellationToken).IsReferenceTypeOrNullableType())
{
newNode = CoalesceExpression(newNode.Parenthesize(), whenNull.Parenthesize());
}
newNode = newNode
.WithTriviaFrom(conditionalExpression)
.Parenthesize();
return(await document.ReplaceNodeAsync(conditionalExpression, newNode, cancellationToken).ConfigureAwait(false));
}
public static void AnalyzeConditionalExpression(SyntaxNodeAnalysisContext context)
{
if (context.Node.SpanContainsDirectives())
{
return;
}
var conditionalExpression = (ConditionalExpressionSyntax)context.Node;
ConditionalExpressionInfo conditionalExpressionInfo = SyntaxInfo.ConditionalExpressionInfo(conditionalExpression);
if (!conditionalExpressionInfo.Success)
{
return;
}
SemanticModel semanticModel = context.SemanticModel;
CancellationToken cancellationToken = context.CancellationToken;
NullCheckExpressionInfo nullCheck = SyntaxInfo.NullCheckExpressionInfo(conditionalExpressionInfo.Condition, semanticModel: semanticModel, cancellationToken: cancellationToken);
if (!nullCheck.Success)
{
return;
}
ExpressionSyntax whenNotNull = (nullCheck.IsCheckingNotNull) ? conditionalExpressionInfo.WhenTrue : conditionalExpressionInfo.WhenFalse;
ExpressionSyntax whenNull = (nullCheck.IsCheckingNotNull) ? conditionalExpressionInfo.WhenFalse : conditionalExpressionInfo.WhenTrue;
if (SyntaxComparer.AreEquivalent(nullCheck.Expression, whenNotNull))
{
if (semanticModel
.GetTypeSymbol(nullCheck.Expression, cancellationToken)?
.IsReferenceTypeOrNullableType() == true)
{
context.ReportDiagnostic(
DiagnosticDescriptors.UseCoalesceExpressionInsteadOfConditionalExpression,
conditionalExpression);
}
}
else if (whenNotNull.IsKind(
SyntaxKind.SimpleMemberAccessExpression,
SyntaxKind.ElementAccessExpression,
SyntaxKind.ConditionalAccessExpression,
SyntaxKind.InvocationExpression))
{
ExpressionSyntax expression = UseConditionalAccessRefactoring.FindExpressionThatCanBeConditionallyAccessed(nullCheck.Expression, whenNotNull);
if (expression == null)
{
return;
}
ITypeSymbol typeSymbol = semanticModel.GetTypeSymbol(nullCheck.Expression, cancellationToken);
if (typeSymbol == null)
{
return;
}
if (typeSymbol.IsReferenceType)
{
Analyze(context, conditionalExpressionInfo, whenNull, whenNotNull, semanticModel, cancellationToken);
}
else if (typeSymbol.IsConstructedFrom(SpecialType.System_Nullable_T))
{
if (expression.IsParentKind(SyntaxKind.SimpleMemberAccessExpression))
{
var memberAccessExpression = (MemberAccessExpressionSyntax)expression.Parent;
if (!memberAccessExpression.IsParentKind(SyntaxKind.InvocationExpression) &&
(memberAccessExpression.Name as IdentifierNameSyntax)?.Identifier.ValueText == "Value")
{
if (memberAccessExpression == whenNotNull)
{
context.ReportDiagnostic(
DiagnosticDescriptors.UseCoalesceExpressionInsteadOfConditionalExpression,
conditionalExpression);
}
else
{
Analyze(context, conditionalExpressionInfo, whenNull, whenNotNull, semanticModel, cancellationToken);
}
}
}
}
}
}
public sealed override async Task RegisterCodeFixesAsync(CodeFixContext context)
{
SyntaxNode root = await context.GetSyntaxRootAsync().ConfigureAwait(false);
if (!TryFindFirstAncestorOrSelf(root, context.Span, out TypeParameterConstraintSyntax constraint))
{
return;
}
foreach (Diagnostic diagnostic in context.Diagnostics)
{
switch (diagnostic.Id)
{
case CompilerDiagnosticIdentifiers.NewConstraintMustBeLastConstraintSpecified:
{
if (!Settings.IsEnabled(diagnostic.Id, CodeFixIdentifiers.MoveConstraint))
{
break;
}
TypeParameterConstraintInfo constraintInfo = SyntaxInfo.TypeParameterConstraintInfo(constraint);
if (!constraintInfo.Success)
{
break;
}
MoveConstraint(context, diagnostic, constraintInfo, constraintInfo.Constraints.Count - 1);
break;
}
case CompilerDiagnosticIdentifiers.DuplicateConstraintForTypeParameter:
{
if (Settings.IsEnabled(diagnostic.Id, CodeFixIdentifiers.RemoveConstraint))
{
RemoveConstraint(context, diagnostic, constraint);
}
break;
}
case CompilerDiagnosticIdentifiers.ClassOrStructConstraintMustComeBeforeAnyOtherConstraints:
{
if (!Settings.IsEnabled(diagnostic.Id, CodeFixIdentifiers.MoveConstraint))
{
break;
}
TypeParameterConstraintInfo constraintInfo = SyntaxInfo.TypeParameterConstraintInfo(constraint);
if (!constraintInfo.Success)
{
break;
}
if (constraintInfo.IsDuplicateConstraint)
{
RemoveConstraint(context, diagnostic, constraint);
}
else
{
MoveConstraint(context, diagnostic, constraintInfo, 0);
}
break;
}
case CompilerDiagnosticIdentifiers.CannotSpecifyBothConstraintClassAndClassOrStructConstraint:
{
if (!Settings.IsEnabled(diagnostic.Id, CodeFixIdentifiers.RemoveConstraint))
{
break;
}
TypeParameterConstraintInfo constraintInfo = SyntaxInfo.TypeParameterConstraintInfo(constraint);
if (!constraintInfo.Success)
{
break;
}
RemoveConstraint(context, diagnostic, constraint);
TypeParameterConstraintSyntax classConstraint = constraintInfo.Constraints.Find(SyntaxKind.ClassConstraint);
if (classConstraint != null)
{
RemoveConstraint(context, diagnostic, classConstraint);
}
TypeParameterConstraintSyntax structConstraint = constraintInfo.Constraints.Find(SyntaxKind.StructConstraint);
if (structConstraint != null)
{
RemoveConstraint(context, diagnostic, structConstraint);
}
break;
}
case CompilerDiagnosticIdentifiers.NewConstraintCannotBeUsedWithStructConstraint:
{
if (!Settings.IsEnabled(diagnostic.Id, CodeFixIdentifiers.RemoveConstraint))
{
break;
}
RemoveConstraint(context, diagnostic, constraint);
TypeParameterConstraintInfo constraintInfo = SyntaxInfo.TypeParameterConstraintInfo(constraint);
if (!constraintInfo.Success)
{
break;
}
TypeParameterConstraintSyntax structConstraint = constraintInfo.Constraints.Find(SyntaxKind.StructConstraint);
RemoveConstraint(context, diagnostic, structConstraint);
break;
}
}
}
}
public static void AnalyzeLocalDeclarationStatement(SyntaxNodeAnalysisContext context)
{
if (context.Node.ContainsDiagnostics)
{
return;
}
var localDeclaration = (LocalDeclarationStatementSyntax)context.Node;
if (localDeclaration.IsConst)
{
return;
}
StatementListInfo statementsInfo = SyntaxInfo.StatementListInfo(localDeclaration);
if (!statementsInfo.Success)
{
return;
}
SyntaxList <StatementSyntax> statements = statementsInfo.Statements;
if (statements.Count <= 1)
{
return;
}
int index = statements.IndexOf(localDeclaration);
if (index == statements.Count - 1)
{
return;
}
LocalDeclarationStatementInfo localInfo = SyntaxInfo.LocalDeclarationStatementInfo(localDeclaration);
if (!localInfo.Success)
{
return;
}
ITypeSymbol typeSymbol = context.SemanticModel.GetTypeSymbol(localInfo.Type, context.CancellationToken);
if (typeSymbol?.SupportsConstantValue() != true)
{
return;
}
foreach (VariableDeclaratorSyntax declarator in localInfo.Variables)
{
if (!HasConstantValue(declarator.Initializer?.Value, typeSymbol, context.SemanticModel, context.CancellationToken))
{
return;
}
}
if (!CanBeMarkedAsConst(localInfo.Variables, statements, index + 1))
{
return;
}
context.ReportDiagnostic(DiagnosticDescriptors.MarkLocalVariableAsConst, localInfo.Type);
}
public static void AnalyzeSwitchStatement(SyntaxNodeAnalysisContext context)
{
var switchStatement = (SwitchStatementSyntax)context.Node;
StatementListInfo statementsInfo = SyntaxInfo.StatementListInfo(switchStatement);
if (!statementsInfo.Success)
{
return;
}
ReturnStatementSyntax returnStatement = FindReturnStatementBelow(statementsInfo.Statements, switchStatement);
ExpressionSyntax expression = returnStatement?.Expression;
if (expression == null)
{
return;
}
if (switchStatement.SpanOrTrailingTriviaContainsDirectives())
{
return;
}
if (returnStatement.SpanOrLeadingTriviaContainsDirectives())
{
return;
}
SemanticModel semanticModel = context.SemanticModel;
CancellationToken cancellationToken = context.CancellationToken;
ISymbol symbol = semanticModel.GetSymbol(expression, cancellationToken);
if (symbol == null)
{
return;
}
if (!IsLocalDeclaredInScopeOrNonRefOrOutParameterOfEnclosingSymbol(symbol, statementsInfo.Parent, semanticModel, cancellationToken))
{
return;
}
foreach (SwitchSectionSyntax section in switchStatement.Sections)
{
SyntaxList <StatementSyntax> statements = section.GetStatements();
if (statements.Count <= 1)
{
return;
}
if (!statements.Last().IsKind(SyntaxKind.BreakStatement))
{
return;
}
if (!IsSymbolAssignedInStatement(symbol, statements[statements.Count - 2], semanticModel, cancellationToken))
{
return;
}
}
DiagnosticHelpers.ReportDiagnostic(context, DiagnosticDescriptors.UseReturnInsteadOfAssignment, switchStatement);
}
private static void AnalyzeIfStatement(SyntaxNodeAnalysisContext context)
{
var ifStatement = (IfStatementSyntax)context.Node;
if (ifStatement.ContainsDiagnostics)
{
return;
}
if (ifStatement.SpanContainsDirectives())
{
return;
}
if (!ifStatement.IsSimpleIf())
{
return;
}
SyntaxList <StatementSyntax> statements = SyntaxInfo.StatementListInfo(ifStatement).Statements;
if (!statements.Any())
{
return;
}
if (IsPartOfLazyInitialization())
{
return;
}
NullCheckExpressionInfo nullCheck = SyntaxInfo.NullCheckExpressionInfo(
ifStatement.Condition,
semanticModel: context.SemanticModel,
allowedStyles: NullCheckStyles.CheckingNull,
cancellationToken: context.CancellationToken);
if (!nullCheck.Success)
{
return;
}
SimpleAssignmentStatementInfo assignmentInfo = SyntaxInfo.SimpleAssignmentStatementInfo(ifStatement.SingleNonBlockStatementOrDefault());
if (!assignmentInfo.Success)
{
return;
}
if (!CSharpFactory.AreEquivalent(assignmentInfo.Left, nullCheck.Expression))
{
return;
}
if (!assignmentInfo.Right.IsSingleLine())
{
return;
}
int index = statements.IndexOf(ifStatement);
if (index > 0 &&
!context.IsAnalyzerSuppressed(DiagnosticDescriptors.UseCoalesceExpression))
{
StatementSyntax previousStatement = statements[index - 1];
if (!previousStatement.ContainsDiagnostics &&
!previousStatement.GetTrailingTrivia().Any(f => f.IsDirective) &&
!ifStatement.GetLeadingTrivia().Any(f => f.IsDirective) &&
CanUseCoalesceExpression(previousStatement, nullCheck.Expression))
{
DiagnosticHelpers.ReportDiagnostic(context, DiagnosticDescriptors.UseCoalesceExpression, previousStatement);
}
}
if (context.IsAnalyzerSuppressed(DiagnosticDescriptors.InlineLazyInitialization))
{
return;
}
if (index == statements.Count - 1)
{
return;
}
StatementSyntax nextStatement = statements[index + 1];
if (nextStatement.ContainsDiagnostics)
{
return;
}
SimpleMemberInvocationStatementInfo invocationInfo = SyntaxInfo.SimpleMemberInvocationStatementInfo(nextStatement);
if (!invocationInfo.Success)
{
return;
}
if (!CSharpFactory.AreEquivalent(nullCheck.Expression, invocationInfo.Expression))
{
return;
}
if (ifStatement.GetTrailingTrivia().Any(f => f.IsDirective))
{
return;
}
if (nextStatement.SpanOrLeadingTriviaContainsDirectives())
{
return;
}
DiagnosticHelpers.ReportDiagnostic(context, DiagnosticDescriptors.InlineLazyInitialization, ifStatement);
bool IsPartOfLazyInitialization()
{
return(statements.Count == 2 &&
statements.IndexOf(ifStatement) == 0 &&
statements[1].IsKind(SyntaxKind.ReturnStatement));
}
}
private static bool CanRefactor(SyntaxNode node)
{
return(node.IsKind(SyntaxKind.LogicalAndExpression, SyntaxKind.LogicalOrExpression) &&
SyntaxInfo.BinaryExpressionInfo((BinaryExpressionSyntax)node).Success);
}
public static async Task ComputeRefactoringsAsync(RefactoringContext context, InvocationExpressionSyntax invocation)
{
SimpleMemberInvocationExpressionInfo invocationInfo = SyntaxInfo.SimpleMemberInvocationExpressionInfo(invocation);
if (!invocationInfo.Success)
{
return;
}
switch (invocationInfo.NameText)
{
case "First":
{
if (invocationInfo.Arguments.Any())
{
break;
}
SemanticModel semanticModel = await context.GetSemanticModelAsync().ConfigureAwait(false);
if (!UseElementAccessAnalysis.IsFixableFirst(invocationInfo, semanticModel, context.CancellationToken))
{
break;
}
context.RegisterRefactoring(
"Use [] instead of calling 'First'",
cancellationToken => UseElementAccessInsteadOfEnumerableMethodRefactoring.UseElementAccessInsteadOfFirstAsync(context.Document, invocation, cancellationToken),
RefactoringIdentifiers.UseElementAccessInsteadOfEnumerableMethod);
break;
}
case "Last":
{
if (invocationInfo.Arguments.Any())
{
break;
}
SemanticModel semanticModel = await context.GetSemanticModelAsync().ConfigureAwait(false);
if (!UseElementAccessAnalysis.IsFixableLast(invocationInfo, semanticModel, context.CancellationToken))
{
break;
}
string propertyName = CSharpUtility.GetCountOrLengthPropertyName(invocationInfo.Expression, semanticModel, context.CancellationToken);
if (propertyName == null)
{
break;
}
context.RegisterRefactoring(
"Use [] instead of calling 'Last'",
cancellationToken => UseElementAccessInsteadOfEnumerableMethodRefactoring.UseElementAccessInsteadOfLastAsync(context.Document, invocation, propertyName, cancellationToken),
RefactoringIdentifiers.UseElementAccessInsteadOfEnumerableMethod);
break;
}
case "ElementAt":
{
if (invocationInfo.Arguments.SingleOrDefault(shouldThrow: false)?.Expression?.IsMissing != false)
{
break;
}
SemanticModel semanticModel = await context.GetSemanticModelAsync().ConfigureAwait(false);
if (!UseElementAccessAnalysis.IsFixableElementAt(invocationInfo, semanticModel, context.CancellationToken))
{
break;
}
context.RegisterRefactoring(
"Use [] instead of calling 'ElementAt'",
cancellationToken => UseElementAccessInsteadOfEnumerableMethodRefactoring.UseElementAccessInsteadOfElementAtAsync(context.Document, invocation, cancellationToken),
RefactoringIdentifiers.UseElementAccessInsteadOfEnumerableMethod);
break;
}
}
}
public sealed override async Task RegisterCodeFixesAsync(CodeFixContext context)
{
SyntaxNode root = await context.GetSyntaxRootAsync().ConfigureAwait(false);
if (!TryFindFirstAncestorOrSelf(root, context.Span, out InvocationExpressionSyntax invocation))
{
return;
}
foreach (Diagnostic diagnostic in context.Diagnostics)
{
switch (diagnostic.Id)
{
case DiagnosticIdentifiers.CombineEnumerableWhereMethodChain:
{
CodeAction codeAction = CodeAction.Create(
"Combine 'Where' method chain",
cancellationToken => CombineEnumerableWhereMethodChainRefactoring.RefactorAsync(context.Document, invocation, cancellationToken),
GetEquivalenceKey(diagnostic));
context.RegisterCodeFix(codeAction, diagnostic);
break;
}
case DiagnosticIdentifiers.UseCountOrLengthPropertyInsteadOfAnyMethod:
{
string propertyName = diagnostic.Properties["PropertyName"];
CodeAction codeAction = CodeAction.Create(
$"Use '{propertyName}' property instead of calling 'Any'",
cancellationToken => UseCountOrLengthPropertyInsteadOfAnyMethodRefactoring.RefactorAsync(context.Document, invocation, propertyName, cancellationToken),
GetEquivalenceKey(diagnostic));
context.RegisterCodeFix(codeAction, diagnostic);
break;
}
case DiagnosticIdentifiers.UseCountOrLengthPropertyInsteadOfCountMethod:
{
string propertyName = diagnostic.Properties["PropertyName"];
CodeAction codeAction = CodeAction.Create(
$"Use '{propertyName}' property instead of calling 'Count'",
cancellationToken => UseCountOrLengthPropertyInsteadOfCountMethodRefactoring.RefactorAsync(context.Document, invocation, diagnostic.Properties["PropertyName"], cancellationToken),
GetEquivalenceKey(diagnostic));
context.RegisterCodeFix(codeAction, diagnostic);
break;
}
case DiagnosticIdentifiers.UseBitwiseOperationInsteadOfCallingHasFlag:
{
CodeAction codeAction = CodeAction.Create(
UseBitwiseOperationInsteadOfCallingHasFlagRefactoring.Title,
cancellationToken => UseBitwiseOperationInsteadOfCallingHasFlagRefactoring.RefactorAsync(context.Document, invocation, cancellationToken),
GetEquivalenceKey(diagnostic));
context.RegisterCodeFix(codeAction, diagnostic);
break;
}
case DiagnosticIdentifiers.RemoveRedundantToStringCall:
{
CodeAction codeAction = CodeAction.Create(
"Remove redundant 'ToString' call",
cancellationToken => context.Document.ReplaceNodeAsync(invocation, RefactoringUtility.RemoveInvocation(invocation).WithFormatterAnnotation(), cancellationToken),
GetEquivalenceKey(diagnostic));
context.RegisterCodeFix(codeAction, diagnostic);
break;
}
case DiagnosticIdentifiers.CallCastInsteadOfSelect:
{
CodeAction codeAction = CodeAction.Create(
"Call 'Cast' instead of 'Select'",
cancellationToken => CallCastInsteadOfSelectRefactoring.RefactorAsync(context.Document, invocation, cancellationToken),
GetEquivalenceKey(diagnostic));
context.RegisterCodeFix(codeAction, diagnostic);
break;
}
case DiagnosticIdentifiers.RemoveRedundantStringToCharArrayCall:
{
CodeAction codeAction = CodeAction.Create(
"Remove redundant 'ToCharArray' call",
cancellationToken => context.Document.ReplaceNodeAsync(invocation, RefactoringUtility.RemoveInvocation(invocation).WithFormatterAnnotation(), cancellationToken),
GetEquivalenceKey(diagnostic));
context.RegisterCodeFix(codeAction, diagnostic);
break;
}
case DiagnosticIdentifiers.CallFindInsteadOfFirstOrDefault:
{
CodeAction codeAction = CodeAction.Create(
"Call 'Find' instead of 'FirstOrDefault'",
cancellationToken => CallFindInsteadOfFirstOrDefaultRefactoring.RefactorAsync(context.Document, invocation, cancellationToken),
GetEquivalenceKey(diagnostic));
context.RegisterCodeFix(codeAction, diagnostic);
break;
}
case DiagnosticIdentifiers.UseElementAccessInsteadOfElementAt:
{
CodeAction codeAction = CodeAction.Create(
"Use [] instead of calling 'ElementAt'",
cancellationToken => UseElementAccessInsteadOfElementAtRefactoring.RefactorAsync(context.Document, invocation, cancellationToken),
GetEquivalenceKey(diagnostic));
context.RegisterCodeFix(codeAction, diagnostic);
break;
}
case DiagnosticIdentifiers.UseElementAccessInsteadOfFirst:
{
CodeAction codeAction = CodeAction.Create(
"Use [] instead of calling 'First'",
cancellationToken => UseElementAccessInsteadOfFirstRefactoring.RefactorAsync(context.Document, invocation, cancellationToken),
GetEquivalenceKey(diagnostic));
context.RegisterCodeFix(codeAction, diagnostic);
break;
}
case DiagnosticIdentifiers.CallStringConcatInsteadOfStringJoin:
{
CodeAction codeAction = CodeAction.Create(
"Call 'Concat' instead of 'Join'",
cancellationToken => CallStringConcatInsteadOfStringJoinRefactoring.RefactorAsync(context.Document, invocation, cancellationToken),
GetEquivalenceKey(diagnostic));
context.RegisterCodeFix(codeAction, diagnostic);
break;
}
case DiagnosticIdentifiers.CallDebugFailInsteadOfDebugAssert:
{
CodeAction codeAction = CodeAction.Create(
"Call 'Fail' instead of 'Assert'",
cancellationToken => CallDebugFailInsteadOfDebugAssertRefactoring.RefactorAsync(context.Document, invocation, cancellationToken),
GetEquivalenceKey(diagnostic));
context.RegisterCodeFix(codeAction, diagnostic);
break;
}
case DiagnosticIdentifiers.CallExtensionMethodAsInstanceMethod:
{
CodeAction codeAction = CodeAction.Create(
CallExtensionMethodAsInstanceMethodRefactoring.Title,
cancellationToken => CallExtensionMethodAsInstanceMethodRefactoring.RefactorAsync(context.Document, invocation, cancellationToken),
GetEquivalenceKey(diagnostic));
context.RegisterCodeFix(codeAction, diagnostic);
break;
}
case DiagnosticIdentifiers.CallThenByInsteadOfOrderBy:
{
SimpleMemberInvocationExpressionInfo invocationInfo = SyntaxInfo.SimpleMemberInvocationExpressionInfo(invocation);
string oldName = invocationInfo.NameText;
string newName = (string.Equals(oldName, "OrderBy", StringComparison.Ordinal))
? "ThenBy"
: "ThenByDescending";
CodeAction codeAction = CodeAction.Create(
$"Call '{newName}' instead of '{oldName}'",
cancellationToken => CallThenByInsteadOfOrderByRefactoring.RefactorAsync(context.Document, invocation, newName, cancellationToken),
GetEquivalenceKey(diagnostic));
context.RegisterCodeFix(codeAction, diagnostic);
break;
}
}
}
}
internal static bool IsFixable(
PropertyDeclarationSyntax propertyDeclaration,
AccessorDeclarationSyntax accessor,
SemanticModel semanticModel,
CancellationToken cancellationToken)
{
switch (accessor.Kind())
{
case SyntaxKind.GetAccessorDeclaration:
{
ExpressionSyntax expression = GetGetAccessorExpression(accessor);
if (expression?.IsKind(SyntaxKind.SimpleMemberAccessExpression) != true)
{
return(false);
}
var memberAccess = (MemberAccessExpressionSyntax)expression;
if (memberAccess.Expression?.IsKind(SyntaxKind.BaseExpression) != true)
{
return(false);
}
SimpleNameSyntax simpleName = memberAccess.Name;
IPropertySymbol propertySymbol = semanticModel.GetDeclaredSymbol(propertyDeclaration, cancellationToken);
if (propertySymbol == null)
{
return(false);
}
IPropertySymbol overriddenProperty = propertySymbol.OverriddenProperty;
if (overriddenProperty == null)
{
return(false);
}
ISymbol symbol = semanticModel.GetSymbol(simpleName, cancellationToken);
return(overriddenProperty.Equals(symbol));
}
case SyntaxKind.SetAccessorDeclaration:
{
ExpressionSyntax expression = GetSetAccessorExpression(accessor);
SimpleAssignmentExpressionInfo assignment = SyntaxInfo.SimpleAssignmentExpressionInfo(expression);
if (!assignment.Success)
{
return(false);
}
if (assignment.Left.Kind() != SyntaxKind.SimpleMemberAccessExpression)
{
return(false);
}
var memberAccess = (MemberAccessExpressionSyntax)assignment.Left;
if (memberAccess.Expression?.IsKind(SyntaxKind.BaseExpression) != true)
{
return(false);
}
if (assignment.Right.Kind() != SyntaxKind.IdentifierName)
{
return(false);
}
var identifierName = (IdentifierNameSyntax)assignment.Right;
if (identifierName.Identifier.ValueText != "value")
{
return(false);
}
SimpleNameSyntax simpleName = memberAccess.Name;
if (simpleName == null)
{
return(false);
}
IPropertySymbol propertySymbol = semanticModel.GetDeclaredSymbol(propertyDeclaration, cancellationToken);
if (propertySymbol == null)
{
return(false);
}
IPropertySymbol overriddenProperty = propertySymbol.OverriddenProperty;
if (overriddenProperty == null)
{
return(false);
}
ISymbol symbol = semanticModel.GetSymbol(simpleName, cancellationToken);
return(overriddenProperty.Equals(symbol));
}
case SyntaxKind.UnknownAccessorDeclaration:
{
return(false);
}
default:
{
Debug.Fail(accessor.Kind().ToString());
return(false);
}
}
}
public static void Analyze(SyntaxNodeAnalysisContext context, MemberInvocationExpressionInfo invocationInfo)
{
INamedTypeSymbol stringBuilderSymbol = context.GetTypeByMetadataName(MetadataNames.System_Text_StringBuilder);
if (stringBuilderSymbol != null)
{
InvocationExpressionSyntax invocationExpression = invocationInfo.InvocationExpression;
if (context.SemanticModel.TryGetMethodInfo(invocationExpression, out MethodInfo methodInfo, context.CancellationToken) &&
!methodInfo.IsExtensionMethod &&
methodInfo.ContainingType?.Equals(stringBuilderSymbol) == true)
{
ImmutableArray <IParameterSymbol> parameters = methodInfo.Parameters;
SeparatedSyntaxList <ArgumentSyntax> arguments = invocationInfo.Arguments;
if (parameters.Length == 1 &&
arguments.Count == 1 &&
methodInfo.IsName("Append", "AppendLine"))
{
ArgumentSyntax argument = arguments.First();
ExpressionSyntax expression = argument.Expression;
SyntaxKind expressionKind = expression.Kind();
switch (expressionKind)
{
case SyntaxKind.InterpolatedStringExpression:
{
context.ReportDiagnostic(DiagnosticDescriptors.OptimizeStringBuilderAppendCall, argument, methodInfo.Name);
return;
}
case SyntaxKind.AddExpression:
{
StringConcatenationExpressionInfo concatenationInfo = SyntaxInfo.StringConcatenationExpressionInfo((BinaryExpressionSyntax)expression, context.SemanticModel, context.CancellationToken);
if (concatenationInfo.Success)
{
context.ReportDiagnostic(DiagnosticDescriptors.OptimizeStringBuilderAppendCall, argument, methodInfo.Name);
return;
}
break;
}
default:
{
if (expressionKind == SyntaxKind.InvocationExpression &&
IsFixable((InvocationExpressionSyntax)expression, context.SemanticModel, context.CancellationToken))
{
context.ReportDiagnostic(DiagnosticDescriptors.OptimizeStringBuilderAppendCall, argument, methodInfo.Name);
return;
}
if (methodInfo.IsName("Append") &&
parameters.Length == 1 &&
parameters[0].Type.IsObject() &&
context.SemanticModel.GetTypeSymbol(argument.Expression, context.CancellationToken).IsValueType)
{
context.ReportDiagnostic(DiagnosticDescriptors.AvoidBoxingOfValueType, argument);
return;
}
break;
}
}
}
else if (parameters.Length > 1 &&
methodInfo.IsName("Insert") &&
methodInfo.HasParameters(SpecialType.System_Int32, SpecialType.System_Object) &&
context.SemanticModel
.GetTypeSymbol(arguments[1].Expression, context.CancellationToken)
.IsValueType)
{
context.ReportDiagnostic(DiagnosticDescriptors.AvoidBoxingOfValueType, arguments[1]);
}
}
}
}
private static void AnalyzeMethodDeclaration(SyntaxNodeAnalysisContext context)
{
var methodDeclaration = (MethodDeclarationSyntax)context.Node;
if (methodDeclaration.ContainsDirectives)
{
return;
}
if (methodDeclaration.ContainsDiagnostics)
{
return;
}
if (methodDeclaration.AttributeLists.Any())
{
return;
}
if (!CheckModifiers(methodDeclaration.Modifiers))
{
return;
}
if (methodDeclaration.HasDocumentationComment())
{
return;
}
if (!methodDeclaration.DescendantTrivia(methodDeclaration.Span).All(f => f.IsWhitespaceOrEndOfLineTrivia()))
{
return;
}
ExpressionSyntax expression = GetMethodExpression(methodDeclaration);
SimpleMemberInvocationExpressionInfo invocationInfo = SyntaxInfo.SimpleMemberInvocationExpressionInfo(expression);
if (!invocationInfo.Success)
{
return;
}
if (invocationInfo.Expression.Kind() != SyntaxKind.BaseExpression)
{
return;
}
SemanticModel semanticModel = context.SemanticModel;
CancellationToken cancellationToken = context.CancellationToken;
IMethodSymbol methodSymbol = semanticModel.GetDeclaredSymbol(methodDeclaration, cancellationToken);
if (methodSymbol == null)
{
return;
}
IMethodSymbol overriddenMethod = methodSymbol.OverriddenMethod;
if (overriddenMethod == null)
{
return;
}
ISymbol symbol = semanticModel.GetSymbol(invocationInfo.Name, cancellationToken);
if (!overriddenMethod.Equals(symbol))
{
return;
}
if (!CheckParameters(methodDeclaration.ParameterList, invocationInfo.ArgumentList, semanticModel, cancellationToken))
{
return;
}
if (!CheckDefaultValues(methodSymbol.Parameters, overriddenMethod.Parameters))
{
return;
}
DiagnosticHelpers.ReportDiagnostic(context,
DiagnosticDescriptors.RemoveRedundantOverridingMember,
methodDeclaration,
CSharpFacts.GetTitle(methodDeclaration));
}
private static void AnalyzeWhileStatement(SyntaxNodeAnalysisContext context)
{
var whileStatement = (WhileStatementSyntax)context.Node;
ExpressionSyntax condition = whileStatement.Condition;
if (condition.IsMissing)
{
return;
}
if (!condition.IsSingleLine())
{
return;
}
StatementSyntax statement = whileStatement.Statement;
if (!(statement is BlockSyntax block))
{
return;
}
SyntaxList <StatementSyntax> innerStatements = block.Statements;
if (innerStatements.Count <= 1)
{
return;
}
ExpressionSyntax incrementedExpression = GetIncrementedExpression(innerStatements.Last());
if (!incrementedExpression.IsKind(SyntaxKind.IdentifierName))
{
return;
}
SyntaxList <StatementSyntax> outerStatements = SyntaxInfo.StatementListInfo(whileStatement).Statements;
int index = outerStatements.IndexOf(whileStatement);
if (index <= 0)
{
return;
}
SingleLocalDeclarationStatementInfo localInfo = GetLocalInfo(outerStatements[index - 1]);
if (!localInfo.Success)
{
return;
}
if (index > 1)
{
SingleLocalDeclarationStatementInfo localInfo2 = GetLocalInfo(outerStatements[index - 2]);
if (localInfo2.Success)
{
ExpressionSyntax incrementedExpression2 = GetIncrementedExpression(innerStatements[innerStatements.Count - 2]);
if (incrementedExpression2 is IdentifierNameSyntax identifierName2 &&
string.Equals(localInfo2.Identifier.ValueText, identifierName2.Identifier.ValueText, StringComparison.Ordinal))
{
return;
}
}
}
var identifierName = (IdentifierNameSyntax)incrementedExpression;
if (!string.Equals(localInfo.Identifier.ValueText, identifierName.Identifier.ValueText, StringComparison.Ordinal))
{
return;
}
if (ContainsContinueStatement())
{
return;
}
SemanticModel semanticModel = context.SemanticModel;
CancellationToken cancellationToken = context.CancellationToken;
ISymbol symbol = semanticModel.GetDeclaredSymbol(localInfo.Declarator, cancellationToken);
if (symbol?.Kind != SymbolKind.Local)
{
return;
}
if (IsLocalVariableReferencedAfterWhileStatement())
{
return;
}
DiagnosticHelpers.ReportDiagnostic(context, DiagnosticRules.UseForStatementInsteadOfWhileStatement, whileStatement.WhileKeyword);
bool ContainsContinueStatement()
{
ContainsContinueStatementWalker walker = ContainsContinueStatementWalker.GetInstance();
walker.ContainsContinueStatement = false;
var containsContinueStatement = false;
foreach (StatementSyntax innerStatement in innerStatements)
{
walker.Visit(innerStatement);
if (walker.ContainsContinueStatement)
{
containsContinueStatement = true;
break;
}
}
ContainsContinueStatementWalker.Free(walker);
return(containsContinueStatement);
}
bool IsLocalVariableReferencedAfterWhileStatement()
{
ContainsLocalOrParameterReferenceWalker walker = ContainsLocalOrParameterReferenceWalker.GetInstance(symbol, semanticModel, cancellationToken);
walker.VisitList(outerStatements, index + 1);
return(ContainsLocalOrParameterReferenceWalker.GetResultAndFree(walker));
}
}
internal static bool IsFixable(
IndexerDeclarationSyntax indexerDeclaration,
AccessorDeclarationSyntax accessor,
SemanticModel semanticModel,
CancellationToken cancellationToken)
{
switch (accessor.Kind())
{
case SyntaxKind.GetAccessorDeclaration:
{
ExpressionSyntax expression = GetGetAccessorExpression(accessor);
if (!(expression is ElementAccessExpressionSyntax elementAccess))
{
return(false);
}
if (elementAccess.Expression?.IsKind(SyntaxKind.BaseExpression) != true)
{
return(false);
}
if (elementAccess.ArgumentList == null)
{
return(false);
}
IPropertySymbol propertySymbol = semanticModel.GetDeclaredSymbol(indexerDeclaration, cancellationToken);
if (propertySymbol == null)
{
return(false);
}
IPropertySymbol overriddenProperty = propertySymbol.OverriddenProperty;
if (overriddenProperty == null)
{
return(false);
}
ISymbol symbol = semanticModel.GetSymbol(elementAccess, cancellationToken);
return(overriddenProperty.Equals(symbol) &&
CheckParameters(indexerDeclaration.ParameterList, elementAccess.ArgumentList, semanticModel, cancellationToken) &&
CheckDefaultValues(propertySymbol.Parameters, overriddenProperty.Parameters));
}
case SyntaxKind.SetAccessorDeclaration:
{
ExpressionSyntax expression = GetSetAccessorExpression(accessor);
SimpleAssignmentExpressionInfo assignment = SyntaxInfo.SimpleAssignmentExpressionInfo(expression);
if (!assignment.Success)
{
return(false);
}
if (assignment.Left.Kind() != SyntaxKind.ElementAccessExpression)
{
return(false);
}
var elementAccess = (ElementAccessExpressionSyntax)assignment.Left;
if (elementAccess.Expression?.IsKind(SyntaxKind.BaseExpression) != true)
{
return(false);
}
if (elementAccess.ArgumentList == null)
{
return(false);
}
if (assignment.Right.Kind() != SyntaxKind.IdentifierName)
{
return(false);
}
var identifierName = (IdentifierNameSyntax)assignment.Right;
if (identifierName.Identifier.ValueText != "value")
{
return(false);
}
IPropertySymbol propertySymbol = semanticModel.GetDeclaredSymbol(indexerDeclaration, cancellationToken);
if (propertySymbol == null)
{
return(false);
}
IPropertySymbol overriddenProperty = propertySymbol.OverriddenProperty;
if (overriddenProperty == null)
{
return(false);
}
ISymbol symbol = semanticModel.GetSymbol(elementAccess, cancellationToken);
return(overriddenProperty.Equals(symbol) &&
CheckParameters(indexerDeclaration.ParameterList, elementAccess.ArgumentList, semanticModel, cancellationToken) &&
CheckDefaultValues(propertySymbol.Parameters, overriddenProperty.Parameters));
}
case SyntaxKind.UnknownAccessorDeclaration:
{
return(false);
}
default:
{
Debug.Fail(accessor.Kind().ToString());
return(false);
}
}
}
private static ReduceIfNestingAnalysisResult AnalyzeCore(
IfStatementSyntax ifStatement,
SemanticModel semanticModel,
SyntaxKind jumpKind,
ReduceIfNestingOptions options,
INamedTypeSymbol taskSymbol = null,
CancellationToken cancellationToken = default(CancellationToken))
{
StatementListInfo statementsInfo = SyntaxInfo.StatementListInfo(ifStatement);
if (!statementsInfo.Success)
{
return(Fail(ifStatement));
}
SyntaxNode node = statementsInfo.Parent;
SyntaxNode parent = node.Parent;
SyntaxKind parentKind = parent.Kind();
SyntaxList <StatementSyntax> statements = statementsInfo.Statements;
if (statementsInfo.IsParentSwitchSection ||
parentKind == SyntaxKind.SwitchSection)
{
SyntaxNode switchSection = (statementsInfo.IsParentSwitchSection) ? node : parent;
if (!options.AllowSwitchSection())
{
return(Fail(switchSection));
}
if (ifStatement != statements.LastButOneOrDefault())
{
return(Fail(switchSection));
}
if (!IsFixableJumpStatement(statements.Last(), ref jumpKind))
{
return(Fail(switchSection));
}
if (!options.AllowNestedFix() &&
IsNestedFix(switchSection.Parent, semanticModel, options, taskSymbol, cancellationToken))
{
return(Fail(switchSection));
}
return(Success(jumpKind, switchSection));
}
if (parentKind.Is(
SyntaxKind.ForStatement,
SyntaxKind.ForEachStatement,
SyntaxKind.DoStatement,
SyntaxKind.WhileStatement))
{
if (!options.AllowLoop())
{
return(Fail(parent));
}
StatementSyntax lastStatement = statements.Last();
if (ifStatement == lastStatement)
{
jumpKind = SyntaxKind.ContinueStatement;
}
else
{
if (ifStatement != statements.LastButOneOrDefault())
{
return(Fail(parent));
}
if (!IsFixableJumpStatement(lastStatement, ref jumpKind))
{
return(Fail(parent));
}
}
if (!options.AllowNestedFix() &&
IsNestedFix(parent.Parent, semanticModel, options, taskSymbol, cancellationToken))
{
return(Fail(parent));
}
return(Success(jumpKind, parent));
}
if (!IsFixable(ifStatement, statements, ref jumpKind))
{
return(Fail(node));
}
switch (parentKind)
{
case SyntaxKind.ConstructorDeclaration:
case SyntaxKind.DestructorDeclaration:
case SyntaxKind.SetAccessorDeclaration:
case SyntaxKind.AddAccessorDeclaration:
case SyntaxKind.RemoveAccessorDeclaration:
{
if (jumpKind == SyntaxKind.None)
{
jumpKind = SyntaxKind.ReturnStatement;
}
else if (jumpKind != SyntaxKind.ReturnStatement)
{
return(Fail(parent));
}
return(Success(jumpKind, parent));
}
case SyntaxKind.OperatorDeclaration:
case SyntaxKind.ConversionOperatorDeclaration:
case SyntaxKind.GetAccessorDeclaration:
{
if (jumpKind == SyntaxKind.None)
{
return(Fail(parent));
}
return(Success(jumpKind, parent));
}
case SyntaxKind.MethodDeclaration:
{
var methodDeclaration = (MethodDeclarationSyntax)parent;
if (jumpKind != SyntaxKind.None)
{
return(Success(jumpKind, parent));
}
if (methodDeclaration.ReturnsVoid())
{
return(Success(SyntaxKind.ReturnStatement, parent));
}
if (methodDeclaration.Modifiers.Contains(SyntaxKind.AsyncKeyword) &&
taskSymbol != null &&
semanticModel
.GetDeclaredSymbol(methodDeclaration, cancellationToken)?
.ReturnType
.Equals(taskSymbol) == true)
{
return(Success(SyntaxKind.ReturnStatement, parent));
}
if (semanticModel
.GetDeclaredSymbol(methodDeclaration, cancellationToken)?
.ReturnType
.OriginalDefinition
.IsIEnumerableOrIEnumerableOfT() == true &&
methodDeclaration.ContainsYield())
{
return(Success(SyntaxKind.YieldBreakStatement, parent));
}
break;
}
case SyntaxKind.LocalFunctionStatement:
{
var localFunction = (LocalFunctionStatementSyntax)parent;
if (jumpKind != SyntaxKind.None)
{
return(Success(jumpKind, parent));
}
if (localFunction.ReturnsVoid())
{
return(Success(SyntaxKind.ReturnStatement, parent));
}
if (localFunction.Modifiers.Contains(SyntaxKind.AsyncKeyword) &&
taskSymbol != null &&
semanticModel.GetDeclaredSymbol(localFunction, cancellationToken)?
.ReturnType
.Equals(taskSymbol) == true)
{
return(Success(SyntaxKind.ReturnStatement, parent));
}
if (semanticModel.GetDeclaredSymbol(localFunction, cancellationToken)?
.ReturnType
.OriginalDefinition
.IsIEnumerableOrIEnumerableOfT() == true &&
localFunction.ContainsYield())
{
return(Success(SyntaxKind.YieldBreakStatement, parent));
}
break;
}
case SyntaxKind.AnonymousMethodExpression:
case SyntaxKind.SimpleLambdaExpression:
case SyntaxKind.ParenthesizedLambdaExpression:
{
var anonymousFunction = (AnonymousFunctionExpressionSyntax)parent;
if (jumpKind != SyntaxKind.None)
{
return(Success(jumpKind, parent));
}
var methodSymbol = semanticModel.GetSymbol(anonymousFunction, cancellationToken) as IMethodSymbol;
if (methodSymbol == null)
{
return(Fail(parent));
}
if (methodSymbol.ReturnsVoid)
{
return(Success(SyntaxKind.ReturnStatement, parent));
}
if (anonymousFunction.AsyncKeyword.Kind() == SyntaxKind.AsyncKeyword &&
methodSymbol.ReturnType.Equals(taskSymbol))
{
return(Success(SyntaxKind.ReturnStatement, parent));
}
break;
}
case SyntaxKind.IfStatement:
{
ifStatement = (IfStatementSyntax)parent;
if (ifStatement.Parent is ElseClauseSyntax elseClause)
{
if (ifStatement.Else != null)
{
return(Fail(parent));
}
if (!options.AllowIfInsideIfElse())
{
return(Fail(parent));
}
return(AnalyzeCore(ifStatement.GetTopmostIf(), semanticModel, jumpKind, options, taskSymbol, cancellationToken));
}
else
{
if (!IsFixable(ifStatement))
{
return(Fail(parent));
}
if (!options.AllowNestedFix())
{
return(Fail(parent));
}
return(AnalyzeCore(ifStatement, semanticModel, jumpKind, options, taskSymbol, cancellationToken));
}
}
case SyntaxKind.ElseClause:
{
if (!options.AllowIfInsideIfElse())
{
return(Fail(parent));
}
var elseClause = (ElseClauseSyntax)parent;
return(AnalyzeCore(elseClause.GetTopmostIf(), semanticModel, jumpKind, options, taskSymbol, cancellationToken));
}
}
return(Fail(parent));
}
private static void AnalyzeAsExpression(SyntaxNodeAnalysisContext context)
{
var asExpression = (BinaryExpressionSyntax)context.Node;
AsExpressionInfo asExpressionInfo = SyntaxInfo.AsExpressionInfo(asExpression);
if (!asExpressionInfo.Success)
{
return;
}
SingleLocalDeclarationStatementInfo localInfo = SyntaxInfo.SingleLocalDeclarationStatementInfo(asExpression);
if (!localInfo.Success)
{
return;
}
if (localInfo.Statement.SpanOrTrailingTriviaContainsDirectives())
{
return;
}
if (!(localInfo.Statement.NextStatement() is IfStatementSyntax ifStatement))
{
return;
}
if (!ifStatement.IsSimpleIf())
{
return;
}
if (ifStatement.SpanOrLeadingTriviaContainsDirectives())
{
return;
}
StatementSyntax statement = ifStatement.SingleNonBlockStatementOrDefault();
if (statement == null)
{
return;
}
if (!CSharpFacts.IsJumpStatement(statement.Kind()))
{
return;
}
NullCheckExpressionInfo nullCheck = SyntaxInfo.NullCheckExpressionInfo(ifStatement.Condition, NullCheckStyles.EqualsToNull | NullCheckStyles.IsNull);
if (!nullCheck.Success)
{
return;
}
if (!string.Equals(localInfo.IdentifierText, (nullCheck.Expression as IdentifierNameSyntax)?.Identifier.ValueText, StringComparison.Ordinal))
{
return;
}
if (!localInfo.Type.IsVar)
{
SemanticModel semanticModel = context.SemanticModel;
CancellationToken cancellationToken = context.CancellationToken;
ITypeSymbol typeSymbol = semanticModel.GetTypeSymbol(asExpressionInfo.Type, cancellationToken);
if (typeSymbol.IsNullableType())
{
return;
}
if (!SymbolEqualityComparer.Default.Equals(semanticModel.GetTypeSymbol(localInfo.Type, cancellationToken), typeSymbol))
{
return;
}
}
DiagnosticHelpers.ReportDiagnostic(context, DiagnosticDescriptors.UsePatternMatchingInsteadOfAsAndNullCheck, localInfo.Statement);
}
private static void AnalyzeIsExpression(SyntaxNodeAnalysisContext context)
{
var isExpression = (BinaryExpressionSyntax)context.Node;
IsExpressionInfo isExpressionInfo = SyntaxInfo.IsExpressionInfo(isExpression);
if (!isExpressionInfo.Success)
{
return;
}
ExpressionSyntax expression = isExpressionInfo.Expression;
var identifierName = expression as IdentifierNameSyntax;
if (identifierName == null)
{
if (expression.IsKind(SyntaxKind.SimpleMemberAccessExpression))
{
var memberAccess = (MemberAccessExpressionSyntax)expression;
if (memberAccess.Expression.IsKind(SyntaxKind.ThisExpression))
{
identifierName = memberAccess.Name as IdentifierNameSyntax;
}
}
if (identifierName == null)
{
return;
}
}
ExpressionSyntax left = isExpression.WalkUpParentheses();
SyntaxNode node = left.Parent;
if (node.ContainsDiagnostics)
{
return;
}
switch (node.Kind())
{
case SyntaxKind.LogicalAndExpression:
{
var logicalAnd = (BinaryExpressionSyntax)node;
if (left != logicalAnd.Left)
{
return;
}
ExpressionSyntax right = logicalAnd.Right;
if (right == null)
{
return;
}
SemanticModel semanticModel = context.SemanticModel;
CancellationToken cancellationToken = context.CancellationToken;
if (semanticModel.GetTypeSymbol(isExpressionInfo.Type, cancellationToken).IsNullableType())
{
return;
}
if (logicalAnd.Parent.IsInExpressionTree(semanticModel, cancellationToken))
{
return;
}
if (!IsFixable(right, identifierName, semanticModel, cancellationToken))
{
return;
}
DiagnosticHelpers.ReportDiagnostic(context, DiagnosticDescriptors.UsePatternMatchingInsteadOfIsAndCast, logicalAnd);
break;
}
case SyntaxKind.IfStatement:
{
var ifStatement = (IfStatementSyntax)node;
if (left != ifStatement.Condition)
{
return;
}
StatementSyntax statement = ifStatement.Statement;
if (statement == null)
{
return;
}
SemanticModel semanticModel = context.SemanticModel;
CancellationToken cancellationToken = context.CancellationToken;
if (semanticModel.GetTypeSymbol(isExpressionInfo.Type, cancellationToken).IsNullableType())
{
return;
}
if (!IsFixable(statement, identifierName, semanticModel, cancellationToken))
{
return;
}
DiagnosticHelpers.ReportDiagnostic(context, DiagnosticDescriptors.UsePatternMatchingInsteadOfIsAndCast, ifStatement.Condition);
break;
}
}
}
public static AccessibilityFlags GetAllowedAccessibilityFlags(MemberDeclarationSelection selectedMembers, bool allowOverride = false)
{
if (selectedMembers.Count < 2)
{
return(AccessibilityFlags.None);
}
var allFlags = AccessibilityFlags.None;
AccessibilityFlags allowedFlags = AccessibilityFlags.Public
| AccessibilityFlags.Internal
| AccessibilityFlags.Protected
| AccessibilityFlags.Private;
foreach (MemberDeclarationSyntax member in selectedMembers)
{
Accessibility accessibility = SyntaxInfo.AccessibilityInfo(member).Accessibility;
if (accessibility == Accessibility.NotApplicable)
{
accessibility = member.GetDefaultExplicitAccessibility();
if (accessibility == Accessibility.NotApplicable)
{
return(AccessibilityFlags.None);
}
}
AccessibilityFlags flag = accessibility.GetAccessibilityFlag();
switch (accessibility)
{
case Accessibility.Private:
case Accessibility.Protected:
case Accessibility.ProtectedAndInternal:
case Accessibility.ProtectedOrInternal:
case Accessibility.Internal:
case Accessibility.Public:
{
allFlags |= flag;
break;
}
default:
{
Debug.Fail(accessibility.ToString());
return(AccessibilityFlags.None);
}
}
foreach (Accessibility accessibility2 in Accessibilities)
{
if (accessibility != accessibility2 &&
!CSharpUtility.IsAllowedAccessibility(member, accessibility2, allowOverride: allowOverride))
{
allowedFlags &= ~accessibility2.GetAccessibilityFlag();
}
}
}
switch (allFlags)
{
case AccessibilityFlags.Private:
case AccessibilityFlags.Protected:
case AccessibilityFlags.Internal:
case AccessibilityFlags.Public:
{
allowedFlags &= ~allFlags;
break;
}
}
return(allowedFlags);
}
