private static Task <Document> RefactorAsync(
Document document,
ExpressionSyntax expression,
ISymbol symbol,
Optional <object> optional,
SemanticModel semanticModel,
CancellationToken cancellationToken)
{
LiteralExpressionSyntax literalExpression = (optional.HasValue)
? LiteralExpression(optional.Value)
: GetLiteralExpression(symbol, semanticModel, cancellationToken);
SyntaxNode oldNode = expression;
if (oldNode.IsParentKind(SyntaxKind.SimpleMemberAccessExpression))
{
var memberAccessExpression = (MemberAccessExpressionSyntax)oldNode.Parent;
if (memberAccessExpression.Name == expression)
{
oldNode = memberAccessExpression;
}
}
return(document.ReplaceNodeAsync(oldNode, literalExpression.WithTriviaFrom(expression).Parenthesize(), cancellationToken));
}
private static Task <Document> RefactorAsync(
Document document,
LiteralExpressionSyntax literalExpression,
LiteralExpressionSyntax newLiteralExpression,
CancellationToken cancellationToken)
{
newLiteralExpression = newLiteralExpression.WithTriviaFrom(literalExpression);
return(document.ReplaceNodeAsync(literalExpression, newLiteralExpression, cancellationToken));
}
private static ExpressionSyntax GetNewNode(PrefixUnaryExpressionSyntax logicalNot)
{
ExpressionSyntax operand = logicalNot.Operand;
ExpressionSyntax expression = operand.WalkDownParentheses();
switch (expression.Kind())
{
case SyntaxKind.TrueLiteralExpression:
case SyntaxKind.FalseLiteralExpression:
{
LiteralExpressionSyntax newNode = BooleanLiteralExpression(expression.Kind() == SyntaxKind.FalseLiteralExpression);
newNode = newNode.WithTriviaFrom(expression);
return(operand.ReplaceNode(expression, newNode));
}
case SyntaxKind.LogicalNotExpression:
{
return(((PrefixUnaryExpressionSyntax)expression).Operand);
}
case SyntaxKind.EqualsExpression:
{
var equalsExpression = (BinaryExpressionSyntax)expression;
BinaryExpressionSyntax notEqualsExpression = NotEqualsExpression(
equalsExpression.Left,
SyntaxFactory.Token(SyntaxKind.ExclamationEqualsToken).WithTriviaFrom(equalsExpression.OperatorToken),
equalsExpression.Right);
return(operand.ReplaceNode(equalsExpression, notEqualsExpression));
}
case SyntaxKind.InvocationExpression:
{
var invocationExpression = (InvocationExpressionSyntax)expression;
var memberAccessExpression = (MemberAccessExpressionSyntax)invocationExpression.Expression;
ExpressionSyntax lambdaExpression = invocationExpression.ArgumentList.Arguments.First().Expression.WalkDownParentheses();
SingleParameterLambdaExpressionInfo lambdaInfo = SyntaxInfo.SingleParameterLambdaExpressionInfo(lambdaExpression);
var logicalNot2 = (PrefixUnaryExpressionSyntax)SimplifyLogicalNegationAnalyzer.GetReturnExpression(lambdaInfo.Body).WalkDownParentheses();
InvocationExpressionSyntax newNode = invocationExpression.ReplaceNode(logicalNot2, logicalNot2.Operand.WithTriviaFrom(logicalNot2));
return(SyntaxRefactorings.ChangeInvokedMethodName(newNode, (memberAccessExpression.Name.Identifier.ValueText == "All") ? "Any" : "All"));
}
}
return(null);
}
public static Task <Document> RefactorAsync(
Document document,
LiteralExpressionSyntax literalExpression,
CancellationToken cancellationToken = default(CancellationToken))
{
LiteralExpressionSyntax newNode = (literalExpression.IsKind(SyntaxKind.TrueLiteralExpression))
? FalseLiteralExpression()
: TrueLiteralExpression();
newNode = newNode.WithTriviaFrom(literalExpression);
return(document.ReplaceNodeAsync(literalExpression, newNode, cancellationToken));
}
public sealed override async Task RegisterCodeFixesAsync(CodeFixContext context)
{
SyntaxNode root = await context.GetSyntaxRootAsync().ConfigureAwait(false);
if (!TryFindFirstAncestorOrSelf(root, context.Span, out ExpressionSyntax expression))
{
return;
}
Document document = context.Document;
foreach (Diagnostic diagnostic in context.Diagnostics)
{
switch (diagnostic.Id)
{
case DiagnosticIdentifiers.ExpressionIsAlwaysEqualToTrueOrFalse:
{
if (expression.IsKind(
SyntaxKind.LessThanExpression,
SyntaxKind.LessThanOrEqualExpression,
SyntaxKind.GreaterThanExpression,
SyntaxKind.GreaterThanOrEqualExpression))
{
var binaryExpression = (BinaryExpressionSyntax)expression;
LiteralExpressionSyntax newNode = CSharpFactory.BooleanLiteralExpression(binaryExpression.IsKind(SyntaxKind.GreaterThanOrEqualExpression, SyntaxKind.LessThanOrEqualExpression));
CodeAction codeAction = CodeAction.Create(
$"Replace expression with '{newNode}'",
ct => document.ReplaceNodeAsync(binaryExpression, newNode.WithTriviaFrom(binaryExpression), ct),
GetEquivalenceKey(diagnostic));
context.RegisterCodeFix(codeAction, diagnostic);
}
else
{
CodeAction codeAction = CodeAction.Create(
"Remove null check",
ct => RemoveUnnecessaryNullCheckAsync(document, expression, ct),
GetEquivalenceKey(diagnostic));
context.RegisterCodeFix(codeAction, diagnostic);
}
break;
}
}
}
}
public static async Task <Document> ToStringLiteralAsync(
Document document,
StringExpressionChain chain,
bool multiline,
CancellationToken cancellationToken = default(CancellationToken))
{
BinaryExpressionSyntax binaryExpression = chain.OriginalExpression;
LiteralExpressionSyntax newNode = (multiline)
? chain.ToMultilineStringLiteral()
: chain.ToStringLiteral();
newNode = newNode
.WithTriviaFrom(binaryExpression)
.WithFormatterAnnotation();
return(await document.ReplaceNodeAsync(binaryExpression, newNode, cancellationToken).ConfigureAwait(false));
}
public sealed override async Task RegisterCodeFixesAsync(CodeFixContext context)
{
SyntaxNode root = await context.GetSyntaxRootAsync().ConfigureAwait(false);
if (!TryFindFirstAncestorOrSelf(root, context.Span, out BinaryExpressionSyntax binaryExpression))
{
return;
}
foreach (Diagnostic diagnostic in context.Diagnostics)
{
switch (diagnostic.Id)
{
case DiagnosticIdentifiers.SimplifyBooleanComparison:
{
CodeAction codeAction = CodeAction.Create(
"Simplify boolean comparison",
cancellationToken => SimplifyBooleanComparisonRefactoring.RefactorAsync(context.Document, binaryExpression, cancellationToken),
GetEquivalenceKey(diagnostic));
context.RegisterCodeFix(codeAction, diagnostic);
break;
}
case DiagnosticIdentifiers.CallAnyInsteadOfCount:
{
CodeAction codeAction = CodeAction.Create(
"Call 'Any' instead of 'Count'",
cancellationToken => CallAnyInsteadOfCountRefactoring.RefactorAsync(context.Document, binaryExpression, cancellationToken),
GetEquivalenceKey(diagnostic));
context.RegisterCodeFix(codeAction, diagnostic);
break;
}
case DiagnosticIdentifiers.AvoidNullLiteralExpressionOnLeftSideOfBinaryExpression:
{
CodeAction codeAction = CodeAction.Create(
$"Swap '{binaryExpression.Left}' and '{binaryExpression.Right}'",
cancellationToken => SwapExpressionsInBinaryExpressionRefactoring.RefactorAsync(context.Document, binaryExpression, cancellationToken),
GetEquivalenceKey(diagnostic));
context.RegisterCodeFix(codeAction, diagnostic);
break;
}
case DiagnosticIdentifiers.UseStringIsNullOrEmptyMethod:
{
CodeAction codeAction = CodeAction.Create(
"Use 'string.IsNullOrEmpty' method",
cancellationToken => UseStringIsNullOrEmptyMethodRefactoring.RefactorAsync(context.Document, binaryExpression, cancellationToken),
GetEquivalenceKey(diagnostic));
context.RegisterCodeFix(codeAction, diagnostic);
break;
}
case DiagnosticIdentifiers.SimplifyCoalesceExpression:
{
ExpressionSyntax expression = binaryExpression.Left;
if (expression == null ||
!context.Span.Contains(expression.Span))
{
expression = binaryExpression.Right;
}
CodeAction codeAction = CodeAction.Create(
"Simplify coalesce expression",
cancellationToken => SimplifyCoalesceExpressionRefactoring.RefactorAsync(context.Document, binaryExpression, expression, cancellationToken),
GetEquivalenceKey(diagnostic));
context.RegisterCodeFix(codeAction, diagnostic);
break;
}
case DiagnosticIdentifiers.RemoveRedundantAsOperator:
{
CodeAction codeAction = CodeAction.Create(
"Remove redundant 'as' operator",
cancellationToken => RemoveRedundantAsOperatorRefactoring.RefactorAsync(context.Document, binaryExpression, cancellationToken),
GetEquivalenceKey(diagnostic));
context.RegisterCodeFix(codeAction, diagnostic);
break;
}
case DiagnosticIdentifiers.UseStringLengthInsteadOfComparisonWithEmptyString:
{
CodeAction codeAction = CodeAction.Create(
"Use string.Length",
cancellationToken => UseStringLengthInsteadOfComparisonWithEmptyStringRefactoring.RefactorAsync(context.Document, binaryExpression, cancellationToken),
GetEquivalenceKey(diagnostic));
context.RegisterCodeFix(codeAction, diagnostic);
break;
}
case DiagnosticIdentifiers.UnconstrainedTypeParameterCheckedForNull:
{
SemanticModel semanticModel = await context.GetSemanticModelAsync().ConfigureAwait(false);
ITypeSymbol typeSymbol = semanticModel.GetTypeSymbol(binaryExpression.Left, context.CancellationToken);
CodeAction codeAction = CodeAction.Create(
$"Use EqualityComparer<{typeSymbol.Name}>.Default",
cancellationToken => UnconstrainedTypeParameterCheckedForNullRefactoring.RefactorAsync(context.Document, binaryExpression, typeSymbol, cancellationToken),
GetEquivalenceKey(diagnostic));
context.RegisterCodeFix(codeAction, diagnostic);
break;
}
case DiagnosticIdentifiers.ValueTypeObjectIsNeverEqualToNull:
{
SemanticModel semanticModel = await context.GetSemanticModelAsync().ConfigureAwait(false);
ITypeSymbol typeSymbol = semanticModel.GetTypeSymbol(binaryExpression.Left, context.CancellationToken);
string title = null;
if (CSharpFacts.IsSimpleType(typeSymbol.SpecialType) ||
typeSymbol.ContainsMember <IMethodSymbol>(WellKnownMemberNames.EqualityOperatorName))
{
ExpressionSyntax expression = typeSymbol.GetDefaultValueSyntax(semanticModel, binaryExpression.Right.SpanStart);
title = $"Replace 'null' with '{expression}'";
}
else
{
title = $"Use EqualityComparer<{SymbolDisplay.ToMinimalDisplayString(typeSymbol, semanticModel, binaryExpression.Right.SpanStart, SymbolDisplayFormats.Default)}>.Default";
}
CodeAction codeAction = CodeAction.Create(
title,
cancellationToken => ValueTypeObjectIsNeverEqualToNullRefactoring.RefactorAsync(context.Document, binaryExpression, typeSymbol, cancellationToken),
GetEquivalenceKey(diagnostic));
context.RegisterCodeFix(codeAction, diagnostic);
break;
}
case DiagnosticIdentifiers.JoinStringExpressions:
{
CodeAction codeAction = CodeAction.Create(
"Join string expressions",
cancellationToken => JoinStringExpressionsRefactoring.RefactorAsync(context.Document, binaryExpression, cancellationToken),
GetEquivalenceKey(diagnostic));
context.RegisterCodeFix(codeAction, diagnostic);
break;
}
case DiagnosticIdentifiers.UseExclusiveOrOperator:
{
CodeAction codeAction = CodeAction.Create(
"Use ^ operator",
cancellationToken => UseExclusiveOrOperatorRefactoring.RefactorAsync(context.Document, binaryExpression, cancellationToken),
GetEquivalenceKey(diagnostic));
context.RegisterCodeFix(codeAction, diagnostic);
break;
}
case DiagnosticIdentifiers.SimplifyBooleanExpression:
{
CodeAction codeAction = CodeAction.Create(
"Simplify boolean expression",
cancellationToken => SimplifyBooleanExpressionRefactoring.RefactorAsync(context.Document, binaryExpression, cancellationToken),
GetEquivalenceKey(diagnostic));
context.RegisterCodeFix(codeAction, diagnostic);
break;
}
case DiagnosticIdentifiers.ExpressionIsAlwaysEqualToTrueOrFalse:
{
LiteralExpressionSyntax newNode = BooleanLiteralExpression(binaryExpression.IsKind(SyntaxKind.GreaterThanOrEqualExpression, SyntaxKind.LessThanOrEqualExpression));
CodeAction codeAction = CodeAction.Create(
$"Replace expression with '{newNode}'",
cancellationToken => context.Document.ReplaceNodeAsync(binaryExpression, newNode.WithTriviaFrom(binaryExpression), cancellationToken),
GetEquivalenceKey(diagnostic));
context.RegisterCodeFix(codeAction, diagnostic);
break;
}
}
}
}
public sealed override async Task RegisterCodeFixesAsync(CodeFixContext context)
{
SyntaxNode root = await context.GetSyntaxRootAsync().ConfigureAwait(false);
if (!TryFindFirstAncestorOrSelf(root, context.Span, out ExpressionSyntax expression))
{
return;
}
Document document = context.Document;
foreach (Diagnostic diagnostic in context.Diagnostics)
{
switch (diagnostic.Id)
{
case DiagnosticIdentifiers.ExpressionIsAlwaysEqualToTrueOrFalse:
{
if (expression.IsKind(
SyntaxKind.LessThanExpression,
SyntaxKind.LessThanOrEqualExpression,
SyntaxKind.GreaterThanExpression,
SyntaxKind.GreaterThanOrEqualExpression))
{
var binaryExpression = (BinaryExpressionSyntax)expression;
LiteralExpressionSyntax newNode = BooleanLiteralExpression(binaryExpression.IsKind(SyntaxKind.GreaterThanOrEqualExpression, SyntaxKind.LessThanOrEqualExpression));
CodeAction codeAction = CodeAction.Create(
$"Replace expression with '{newNode}'",
ct => document.ReplaceNodeAsync(binaryExpression, newNode.WithTriviaFrom(binaryExpression), ct),
GetEquivalenceKey(diagnostic));
context.RegisterCodeFix(codeAction, diagnostic);
}
else if (diagnostic.Properties.TryGetValue("DoubleNaN", out string leftOrRight))
{
var binaryExpression = (BinaryExpressionSyntax)expression;
CodeAction codeAction = CodeAction.Create(
$"Call 'IsNaN'",
ct =>
{
ExpressionSyntax newExpression = SimpleMemberInvocationExpression(
CSharpTypeFactory.DoubleType(),
IdentifierName("IsNaN"),
Argument((leftOrRight == "Left") ? binaryExpression.Left.WithoutLeadingTrivia() : binaryExpression.Right.WithoutTrailingTrivia()));
if (binaryExpression.IsKind(SyntaxKind.NotEqualsExpression))
{
newExpression = LogicalNotExpression(newExpression);
}
newExpression = newExpression.Parenthesize().WithTriviaFrom(binaryExpression);
return(document.ReplaceNodeAsync(binaryExpression, newExpression, ct));
},
GetEquivalenceKey(diagnostic));
context.RegisterCodeFix(codeAction, diagnostic);
}
{
CodeAction codeAction = CodeAction.Create(
"Remove null check",
ct => RemoveUnnecessaryNullCheckAsync(document, expression, ct),
GetEquivalenceKey(diagnostic));
context.RegisterCodeFix(codeAction, diagnostic);
}
break;
}
}
}
}
private static ExpressionSyntax GetNewNode(PrefixUnaryExpressionSyntax logicalNot, Document document)
{
ExpressionSyntax operand = logicalNot.Operand;
ExpressionSyntax expression = operand.WalkDownParentheses();
switch (expression.Kind())
{
case SyntaxKind.TrueLiteralExpression:
case SyntaxKind.FalseLiteralExpression:
{
LiteralExpressionSyntax newNode = BooleanLiteralExpression(expression.Kind() == SyntaxKind.FalseLiteralExpression);
newNode = newNode.WithTriviaFrom(expression);
return(operand.ReplaceNode(expression, newNode));
}
case SyntaxKind.LogicalNotExpression:
{
return(((PrefixUnaryExpressionSyntax)expression).Operand);
}
case SyntaxKind.EqualsExpression:
case SyntaxKind.NotEqualsExpression:
case SyntaxKind.LessThanExpression:
case SyntaxKind.LessThanOrEqualExpression:
case SyntaxKind.GreaterThanExpression:
case SyntaxKind.GreaterThanOrEqualExpression:
{
BinaryExpressionSyntax newExpression = SyntaxLogicalInverter.GetInstance(document).InvertBinaryExpression((BinaryExpressionSyntax)expression);
return(operand.ReplaceNode(expression, newExpression));
}
case SyntaxKind.InvocationExpression:
{
var invocationExpression = (InvocationExpressionSyntax)expression;
var memberAccessExpression = (MemberAccessExpressionSyntax)invocationExpression.Expression;
ExpressionSyntax lambdaExpression = invocationExpression.ArgumentList.Arguments[0].Expression.WalkDownParentheses();
SingleParameterLambdaExpressionInfo lambdaInfo = SyntaxInfo.SingleParameterLambdaExpressionInfo(lambdaExpression);
var logicalNot2 = (PrefixUnaryExpressionSyntax)SimplifyLogicalNegationAnalyzer.GetReturnExpression(lambdaInfo.Body).WalkDownParentheses();
InvocationExpressionSyntax newNode = invocationExpression.ReplaceNode(logicalNot2, logicalNot2.Operand.WithTriviaFrom(logicalNot2));
return(SyntaxRefactorings.ChangeInvokedMethodName(newNode, (memberAccessExpression.Name.Identifier.ValueText == "All") ? "Any" : "All"));
}
case SyntaxKind.IsPatternExpression:
{
var isPatternExpression = (IsPatternExpressionSyntax)expression;
var pattern = (ConstantPatternSyntax)isPatternExpression.Pattern;
UnaryPatternSyntax newPattern = NotPattern(pattern.WithoutTrivia()).WithTriviaFrom(pattern);
return(isPatternExpression.WithPattern(newPattern)
.PrependToLeadingTrivia(logicalNot.GetLeadingTrivia())
.AppendToTrailingTrivia(logicalNot.GetTrailingTrivia()));
}
}
return(null);
}