public static Task <Document> RefactorAsync(
Document document,
IfStatementSyntax ifStatement,
CancellationToken cancellationToken)
{
var statement = (ExpressionStatementSyntax)ifStatement.SingleNonBlockStatementOrDefault();
SimpleMemberInvocationStatementInfo invocationInfo = SyntaxInfo.SimpleMemberInvocationStatementInfo(statement);
int insertIndex = invocationInfo.Expression.Span.End - statement.FullSpan.Start;
StatementSyntax newStatement = SyntaxFactory.ParseStatement(statement.ToFullString().Insert(insertIndex, "?"));
IEnumerable <SyntaxTrivia> leading = ifStatement.DescendantTrivia(TextSpan.FromBounds(ifStatement.SpanStart, statement.SpanStart));
newStatement = (leading.All(f => f.IsWhitespaceOrEndOfLineTrivia()))
? newStatement.WithLeadingTrivia(ifStatement.GetLeadingTrivia())
: newStatement.WithLeadingTrivia(ifStatement.GetLeadingTrivia().Concat(leading));
IEnumerable <SyntaxTrivia> trailing = ifStatement.DescendantTrivia(TextSpan.FromBounds(statement.Span.End, ifStatement.Span.End));
newStatement = (leading.All(f => f.IsWhitespaceOrEndOfLineTrivia()))
? newStatement.WithTrailingTrivia(ifStatement.GetTrailingTrivia())
: newStatement.WithTrailingTrivia(trailing.Concat(ifStatement.GetTrailingTrivia()));
return(document.ReplaceNodeAsync(ifStatement, newStatement, cancellationToken));
}
public static void AnalyzeIfStatement(SyntaxNodeAnalysisContext context, INamedTypeSymbol expressionType)
{
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);
if (!nullCheck.Success)
{
return;
}
SimpleMemberInvocationStatementInfo invocationInfo = SyntaxInfo.SimpleMemberInvocationStatementInfo(ifStatement.SingleNonBlockStatementOrDefault());
if (!invocationInfo.Success)
{
return;
}
if (!CSharpFactory.AreEquivalent(nullCheck.Expression, invocationInfo.Expression))
{
return;
}
if (ifStatement.IsInExpressionTree(expressionType, context.SemanticModel, context.CancellationToken))
{
return;
}
context.ReportDiagnostic(DiagnosticDescriptors.UseConditionalAccess, ifStatement);
}
public static async Task <Document> RefactorAsync(
Document document,
IfStatementSyntax ifStatement,
CancellationToken cancellationToken)
{
var statement = (ExpressionStatementSyntax)ifStatement.SingleNonBlockStatementOrDefault();
StatementSyntax newStatement = statement;
NullCheckExpressionInfo nullCheck = SyntaxInfo.NullCheckExpressionInfo(ifStatement.Condition, NullCheckStyles.NotEqualsToNull);
SimpleMemberInvocationStatementInfo invocationInfo = SyntaxInfo.SimpleMemberInvocationStatementInfo(statement);
ExpressionSyntax expression = invocationInfo.Expression;
SemanticModel semanticModel = await document.GetSemanticModelAsync(cancellationToken).ConfigureAwait(false);
if (semanticModel.GetTypeSymbol(nullCheck.Expression, cancellationToken).IsNullableType())
{
var memberAccess = (MemberAccessExpressionSyntax)invocationInfo.Expression;
newStatement = statement.ReplaceNode(memberAccess, memberAccess.Expression.WithTrailingTrivia(memberAccess.GetTrailingTrivia()));
expression = memberAccess.Expression;
}
int insertIndex = expression.Span.End - statement.FullSpan.Start;
newStatement = SyntaxFactory.ParseStatement(newStatement.ToFullString().Insert(insertIndex, "?"));
IEnumerable <SyntaxTrivia> leading = ifStatement.DescendantTrivia(TextSpan.FromBounds(ifStatement.SpanStart, statement.SpanStart));
newStatement = (leading.All(f => f.IsWhitespaceOrEndOfLineTrivia()))
? newStatement.WithLeadingTrivia(ifStatement.GetLeadingTrivia())
: newStatement.WithLeadingTrivia(ifStatement.GetLeadingTrivia().Concat(leading));
IEnumerable <SyntaxTrivia> trailing = ifStatement.DescendantTrivia(TextSpan.FromBounds(statement.Span.End, ifStatement.Span.End));
newStatement = (leading.All(f => f.IsWhitespaceOrEndOfLineTrivia()))
? newStatement.WithTrailingTrivia(ifStatement.GetTrailingTrivia())
: newStatement.WithTrailingTrivia(trailing.Concat(ifStatement.GetTrailingTrivia()));
return(await document.ReplaceNodeAsync(ifStatement, newStatement, cancellationToken).ConfigureAwait(false));
}
public static Task <Document> RefactorAsync(
Document document,
IfStatementSyntax ifStatement,
CancellationToken cancellationToken = default)
{
StatementListInfo statementsInfo = SyntaxInfo.StatementListInfo(ifStatement);
SyntaxList <StatementSyntax> statements = statementsInfo.Statements;
int index = statements.IndexOf(ifStatement);
StatementSyntax expressionStatement = (ExpressionStatementSyntax)statements[index + 1];
SimpleMemberInvocationStatementInfo invocationInfo = SyntaxInfo.SimpleMemberInvocationStatementInfo((ExpressionStatementSyntax)expressionStatement);
ExpressionSyntax expression = invocationInfo.Expression;
SimpleAssignmentStatementInfo assignmentInfo = SyntaxInfo.SimpleAssignmentStatementInfo((ExpressionStatementSyntax)ifStatement.SingleNonBlockStatementOrDefault());
BinaryExpressionSyntax coalesceExpression = CSharpFactory.CoalesceExpression(expression.WithoutTrivia(), ParenthesizedExpression(assignmentInfo.AssignmentExpression));
ParenthesizedExpressionSyntax newExpression = ParenthesizedExpression(coalesceExpression)
.WithTriviaFrom(expression);
StatementSyntax newExpressionStatement = expressionStatement.ReplaceNode(expression, newExpression);
IEnumerable <SyntaxTrivia> trivia = statementsInfo.Parent.DescendantTrivia(TextSpan.FromBounds(ifStatement.FullSpan.Start, expressionStatement.FullSpan.Start));
if (trivia.Any(f => !f.IsWhitespaceOrEndOfLineTrivia()))
{
newExpressionStatement = newExpressionStatement.PrependToLeadingTrivia(trivia);
}
SyntaxList <StatementSyntax> newStatements = statements
.Replace(expressionStatement, newExpressionStatement)
.RemoveAt(index);
return(document.ReplaceStatementsAsync(statementsInfo, newStatements, cancellationToken));
}
private static void AnalyzeUsingStatement(SyntaxNodeAnalysisContext context)
{
var usingStatement = (UsingStatementSyntax)context.Node;
StatementSyntax statement = usingStatement.Statement;
if (statement?.Kind() != SyntaxKind.Block)
{
return;
}
var block = (BlockSyntax)statement;
StatementSyntax lastStatement = block.Statements.LastOrDefault();
if (lastStatement == null)
{
return;
}
if (lastStatement.SpanContainsDirectives())
{
return;
}
SimpleMemberInvocationStatementInfo info = SyntaxInfo.SimpleMemberInvocationStatementInfo(lastStatement);
if (!info.Success)
{
return;
}
if (info.Arguments.Any())
{
return;
}
string methodName = info.NameText;
if (methodName != "Dispose" && methodName != "Close")
{
return;
}
ExpressionSyntax usingExpression = usingStatement.Expression;
if (usingExpression != null)
{
if (CSharpFactory.AreEquivalent(info.Expression, usingExpression))
{
ReportDiagnostic(context, info.Statement, methodName);
}
}
else
{
VariableDeclarationSyntax usingDeclaration = usingStatement.Declaration;
if (usingDeclaration != null &&
info.Expression.Kind() == SyntaxKind.IdentifierName)
{
var identifierName = (IdentifierNameSyntax)info.Expression;
VariableDeclaratorSyntax declarator = usingDeclaration.Variables.LastOrDefault();
if (declarator != null &&
declarator.Identifier.ValueText == identifierName.Identifier.ValueText)
{
ISymbol symbol = context.SemanticModel.GetDeclaredSymbol(declarator, context.CancellationToken);
if (symbol?.Equals(context.SemanticModel.GetSymbol(identifierName, context.CancellationToken)) == true)
{
ReportDiagnostic(context, info.Statement, methodName);
}
}
}
}
}
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));
}
}
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 void AnalyzeIfStatement(SyntaxNodeAnalysisContext context)
{
var ifStatement = (IfStatementSyntax)context.Node;
if (!ifStatement.IsSimpleIf())
{
return;
}
if (ifStatement.ContainsDiagnostics)
{
return;
}
if (ifStatement.SpanContainsDirectives())
{
return;
}
SyntaxList <StatementSyntax> statements = SyntaxInfo.StatementListInfo(ifStatement).Statements;
if (!statements.Any())
{
return;
}
if (IsPartOfLazyInitialization(ifStatement, statements))
{
return;
}
NullCheckExpressionInfo nullCheck = SyntaxInfo.NullCheckExpressionInfo(ifStatement.Condition, semanticModel: context.SemanticModel, cancellationToken: context.CancellationToken);
if (!nullCheck.Success)
{
return;
}
SimpleAssignmentStatementInfo simpleAssignment = SyntaxInfo.SimpleAssignmentStatementInfo(ifStatement.SingleNonBlockStatementOrDefault());
if (!simpleAssignment.Success)
{
return;
}
if (!CSharpFactory.AreEquivalent(simpleAssignment.Left, nullCheck.Expression))
{
return;
}
if (!simpleAssignment.Right.IsSingleLine())
{
return;
}
int index = statements.IndexOf(ifStatement);
if (index > 0)
{
StatementSyntax previousStatement = statements[index - 1];
if (!previousStatement.ContainsDiagnostics &&
IsFixable(previousStatement, ifStatement, nullCheck.Expression, ifStatement.Parent))
{
context.ReportDiagnostic(DiagnosticDescriptors.UseCoalesceExpression, previousStatement);
}
}
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.Parent.ContainsDirectives(TextSpan.FromBounds(ifStatement.SpanStart, nextStatement.Span.End)))
{
return;
}
context.ReportDiagnostic(DiagnosticDescriptors.InlineLazyInitialization, ifStatement);
}
public static Task <Document> InlineLazyInitializationAsync(
Document document,
IfStatementSyntax ifStatement,
CancellationToken cancellationToken = default)
{
StatementListInfo statementsInfo = SyntaxInfo.StatementListInfo(ifStatement);
var assignmentStatement = (ExpressionStatementSyntax)ifStatement.SingleNonBlockStatementOrDefault();
SimpleAssignmentStatementInfo assignmentInfo = SyntaxInfo.SimpleAssignmentStatementInfo(assignmentStatement, walkDownParentheses: false);
ExpressionSyntax right = assignmentInfo.Right;
int index = statementsInfo.IndexOf(ifStatement);
var expressionStatement2 = (ExpressionStatementSyntax)statementsInfo[index + 1];
SimpleMemberInvocationStatementInfo invocationInfo = SyntaxInfo.SimpleMemberInvocationStatementInfo(expressionStatement2);
ExpressionSyntax expression = invocationInfo.Expression;
var newLeading = new List <SyntaxTrivia>(ifStatement.GetLeadingTrivia());
ExpressionSyntax coalesceExpression;
if (document.SupportsLanguageFeature(CSharpLanguageFeature.NullCoalescingAssignmentOperator))
{
AddTrivia(ifStatement.DescendantTrivia(TextSpan.FromBounds(ifStatement.SpanStart, right.SpanStart)).ToSyntaxTriviaList());
coalesceExpression = CoalesceAssignmentExpression(expression.WithoutTrivia(), right.WithoutTrivia());
}
else
{
AddTrivia(ifStatement.DescendantTrivia(TextSpan.FromBounds(ifStatement.SpanStart, assignmentInfo.AssignmentExpression.SpanStart)).ToSyntaxTriviaList());
coalesceExpression = CoalesceExpression(expression.WithoutTrivia(), ParenthesizedExpression(assignmentInfo.AssignmentExpression.WithoutTrivia()));
}
AddTrivia(ifStatement.DescendantTrivia(TextSpan.FromBounds(right.Span.End, ifStatement.Span.End)).ToSyntaxTriviaList());
AddTrivia(ifStatement.GetTrailingTrivia());
AddTrivia(expressionStatement2.GetLeadingTrivia());
ParenthesizedExpressionSyntax newExpression = ParenthesizedExpression(coalesceExpression)
.WithLeadingTrivia(newLeading)
.WithTrailingTrivia(expression.GetTrailingTrivia());
StatementSyntax newExpressionStatement = expressionStatement2.ReplaceNode(expression, newExpression);
StatementListInfo newStatements = statementsInfo
.Replace(expressionStatement2, newExpressionStatement)
.RemoveAt(index);
return(document.ReplaceStatementsAsync(statementsInfo, newStatements, cancellationToken));
void AddTrivia(SyntaxTriviaList trivia)
{
if (!trivia.IsEmptyOrWhitespace())
{
newLeading.AddRange(trivia);
}
}
}