private static async Task <ExpressionSyntax> CreateNewNodeAsync(
Document document,
BinaryExpressionSyntax binaryExpression,
CancellationToken cancellationToken)
{
ExpressionSyntax left = binaryExpression.Left;
ExpressionSyntax right = binaryExpression.Right;
SyntaxTriviaList trivia = binaryExpression
.DescendantTrivia(TextSpan.FromBounds(left.Span.End, right.SpanStart))
.ToSyntaxTriviaList()
.EmptyIfWhitespace();
SemanticModel semanticModel = await document.GetSemanticModelAsync(cancellationToken).ConfigureAwait(false);
if (CSharpFacts.IsBooleanLiteralExpression(left.Kind()))
{
SyntaxTriviaList leadingTrivia = binaryExpression.GetLeadingTrivia().AddRange(trivia);
if (right.IsKind(SyntaxKind.LogicalNotExpression))
{
var logicalNot = (PrefixUnaryExpressionSyntax)right;
ExpressionSyntax operand = logicalNot.Operand;
if (semanticModel.GetTypeInfo(operand, cancellationToken).ConvertedType.IsNullableOf(SpecialType.System_Boolean))
{
return(binaryExpression
.WithLeft(Inverter.LogicallyNegate(left, semanticModel, cancellationToken))
.WithRight(operand.WithTriviaFrom(right)));
}
}
return(Inverter.LogicallyNegate(right, semanticModel, cancellationToken)
.WithLeadingTrivia(leadingTrivia));
}
else if (CSharpFacts.IsBooleanLiteralExpression(right.Kind()))
{
SyntaxTriviaList trailingTrivia = trivia.AddRange(binaryExpression.GetTrailingTrivia());
if (left.IsKind(SyntaxKind.LogicalNotExpression))
{
var logicalNot = (PrefixUnaryExpressionSyntax)left;
ExpressionSyntax operand = logicalNot.Operand;
if (semanticModel.GetTypeInfo(operand, cancellationToken).ConvertedType.IsNullableOf(SpecialType.System_Boolean))
{
return(binaryExpression
.WithLeft(operand.WithTriviaFrom(left))
.WithRight(Inverter.LogicallyNegate(right, semanticModel, cancellationToken)));
}
}
return(Inverter.LogicallyNegate(left, semanticModel, cancellationToken)
.WithTrailingTrivia(trailingTrivia));
}
throw new InvalidOperationException();
}
private static async Task <Document> InvertIfElseAsync(
Document document,
IfStatementSyntax ifStatement,
CancellationToken cancellationToken = default(CancellationToken))
{
cancellationToken.ThrowIfCancellationRequested();
ElseClauseSyntax elseClause = ifStatement.Else;
StatementSyntax whenTrue = ifStatement.Statement;
StatementSyntax whenFalse = elseClause.Statement;
SemanticModel semanticModel = await document.GetSemanticModelAsync(cancellationToken).ConfigureAwait(false);
IfStatementSyntax newIfStatement = ifStatement.Update(
ifKeyword: ifStatement.IfKeyword,
openParenToken: ifStatement.OpenParenToken,
condition: Inverter.LogicallyNegate(ifStatement.Condition, semanticModel, cancellationToken),
closeParenToken: ifStatement.CloseParenToken,
statement: whenFalse.WithTriviaFrom(whenTrue),
@else: elseClause.WithStatement(whenTrue.WithTriviaFrom(whenFalse)));
newIfStatement = newIfStatement.WithFormatterAnnotation();
return(await document.ReplaceNodeAsync(ifStatement, newIfStatement, cancellationToken).ConfigureAwait(false));
}
private static async Task <Document> RefactorAsync(
Document document,
ExpressionSyntax expression,
CancellationToken cancellationToken)
{
SemanticModel semanticModel = await document.GetSemanticModelAsync(cancellationToken).ConfigureAwait(false);
ExpressionSyntax newNode = Inverter.LogicallyNegate(expression, semanticModel, cancellationToken);
return(await document.ReplaceNodeAsync(expression, newNode, cancellationToken).ConfigureAwait(false));
}
private static Task <Document> IfToReturnWithExpressionAsync(
Document document,
IfToReturnWithExpressionAnalysis analysis,
CancellationToken cancellationToken = default(CancellationToken))
{
ExpressionSyntax expression = analysis.Expression;
if (analysis.Invert)
{
expression = Inverter.LogicallyNegate(expression, analysis.SemanticModel, cancellationToken);
}
StatementSyntax statement;
if (analysis.IsYield)
{
statement = YieldReturnStatement(expression);
}
else
{
statement = ReturnStatement(expression);
}
IfStatementSyntax ifStatement = analysis.IfStatement;
if (ifStatement.IsSimpleIf())
{
StatementListInfo statementsInfo = SyntaxInfo.StatementListInfo(ifStatement);
SyntaxList <StatementSyntax> statements = statementsInfo.Statements;
int index = statements.IndexOf(ifStatement);
StatementSyntax newNode = statement
.WithLeadingTrivia(ifStatement.GetLeadingTrivia())
.WithTrailingTrivia(statements[index + 1].GetTrailingTrivia())
.WithFormatterAnnotation();
SyntaxList <StatementSyntax> newStatements = statements
.RemoveAt(index)
.ReplaceAt(index, newNode);
return(document.ReplaceStatementsAsync(statementsInfo, newStatements, cancellationToken));
}
else
{
StatementSyntax newNode = statement
.WithTriviaFrom(ifStatement)
.WithFormatterAnnotation();
return(document.ReplaceNodeAsync(ifStatement, newNode, cancellationToken));
}
}
public static async Task <Document> RefactorAsync(
Document document,
BinaryExpressionSyntax binaryExpression,
CancellationToken cancellationToken = default(CancellationToken))
{
SemanticModel semanticModel = await document.GetSemanticModelAsync(cancellationToken).ConfigureAwait(false);
ExpressionSyntax newNode = Inverter.LogicallyNegate(binaryExpression, semanticModel, cancellationToken);
newNode = newNode.WithFormatterAnnotation();
return(await document.ReplaceNodeAsync(binaryExpression, newNode, cancellationToken).ConfigureAwait(false));
}
public static async Task <Document> RefactorAsync(
Document document,
ConditionalExpressionSyntax conditionalExpression,
CancellationToken cancellationToken = default(CancellationToken))
{
SemanticModel semanticModel = await document.GetSemanticModelAsync(cancellationToken).ConfigureAwait(false);
ConditionalExpressionSyntax newNode = conditionalExpression.Update(
condition: Inverter.LogicallyNegate(conditionalExpression.Condition, semanticModel, cancellationToken),
questionToken: conditionalExpression.QuestionToken,
whenTrue: conditionalExpression.WhenFalse.WithTriviaFrom(conditionalExpression.WhenTrue),
colonToken: conditionalExpression.ColonToken,
whenFalse: conditionalExpression.WhenTrue.WithTriviaFrom(conditionalExpression.WhenFalse));
newNode = newNode.WithFormatterAnnotation();
return(await document.ReplaceNodeAsync(conditionalExpression, newNode, cancellationToken).ConfigureAwait(false));
}
private static Task <Document> IfElseToAssignmentWithConditionAsync(
Document document,
IfElseToAssignmentWithConditionAnalysis analysis,
CancellationToken cancellationToken = default(CancellationToken))
{
ExpressionSyntax right = analysis.Right;
if (analysis.Invert)
{
right = Inverter.LogicallyNegate(right, analysis.SemanticModel, cancellationToken);
}
ExpressionStatementSyntax newNode = SimpleAssignmentStatement(analysis.Left.WithoutTrivia(), right.WithoutTrivia())
.WithTriviaFrom(analysis.IfStatement)
.WithFormatterAnnotation();
return(document.ReplaceNodeAsync(analysis.IfStatement, newNode, cancellationToken));
}
public static async Task <Document> RefactorAsync(
Document document,
InvocationExpressionSyntax invocationExpression,
string memberName,
ExpressionSyntax expression,
CancellationToken cancellationToken = default(CancellationToken))
{
var memberAccessExpression = (MemberAccessExpressionSyntax)invocationExpression.Expression;
MemberAccessExpressionSyntax newMemberAccessExpression = memberAccessExpression
.WithName(SyntaxFactory.IdentifierName(memberName).WithTriviaFrom(memberAccessExpression.Name));
SemanticModel semanticModel = await document.GetSemanticModelAsync(cancellationToken).ConfigureAwait(false);
InvocationExpressionSyntax newNode = invocationExpression
.ReplaceNode(expression, Inverter.LogicallyNegate(expression, semanticModel, cancellationToken))
.WithExpression(newMemberAccessExpression);
return(await document.ReplaceNodeAsync(invocationExpression, newNode, cancellationToken).ConfigureAwait(false));
}
private static async Task <Document> RefactorAsync(
Document document,
IfStatementSyntax ifStatement,
CancellationToken cancellationToken)
{
ExpressionSyntax condition = ifStatement.Condition;
ElseClauseSyntax elseClause = ifStatement.Else;
if ((ifStatement.Statement as BlockSyntax)?.Statements.Any() == false)
{
SemanticModel semanticModel = await document.GetSemanticModelAsync(cancellationToken).ConfigureAwait(false);
ExpressionSyntax newCondition = Inverter.LogicallyNegate(condition, semanticModel, cancellationToken);
StatementSyntax statement = elseClause.Statement;
if (statement is IfStatementSyntax nestedIf)
{
newCondition = LogicalAndExpression(newCondition.Parenthesize(), nestedIf.Condition.Parenthesize());
statement = nestedIf.Statement;
}
cancellationToken.ThrowIfCancellationRequested();
IfStatementSyntax newNode = ifStatement.Update(
ifStatement.IfKeyword,
ifStatement.OpenParenToken,
newCondition,
ifStatement.CloseParenToken,
statement,
default(ElseClauseSyntax));
newNode = newNode.WithFormatterAnnotation();
return(await document.ReplaceNodeAsync(ifStatement, newNode, cancellationToken).ConfigureAwait(false));
}
else if (elseClause != null)
{
WhileStatementSyntax whileStatement;
if (ifStatement.Parent is BlockSyntax block)
{
whileStatement = (WhileStatementSyntax)block.Parent;
}
else
{
block = Block();
whileStatement = (WhileStatementSyntax)ifStatement.Parent;
}
cancellationToken.ThrowIfCancellationRequested();
BlockSyntax newBlock = (ifStatement.Statement is BlockSyntax ifBlock)
? block.WithStatements(ifBlock.Statements)
: block.WithStatements(SingletonList(ifStatement.Statement));
SyntaxNode newNode = whileStatement.Update(
whileStatement.WhileKeyword,
whileStatement.OpenParenToken,
ifStatement.Condition,
whileStatement.CloseParenToken,
newBlock);
newNode = newNode.WithFormatterAnnotation();
return(await document.ReplaceNodeAsync(whileStatement, newNode, cancellationToken).ConfigureAwait(false));
}
else
{
var block = (BlockSyntax)ifStatement.Parent;
SyntaxList <StatementSyntax> statements = block.Statements;
BlockSyntax newBlock = block.WithStatements(statements.Remove(ifStatement));
SemanticModel semanticModel = await document.GetSemanticModelAsync(cancellationToken).ConfigureAwait(false);
ExpressionSyntax newCondition = Inverter.LogicallyNegate(condition, semanticModel, cancellationToken);
SyntaxNode newNode = block.Parent;
switch (block.Parent)
{
case WhileStatementSyntax whileStatement:
{
cancellationToken.ThrowIfCancellationRequested();
if (statements.IsFirst(ifStatement))
{
newNode = whileStatement.Update(
whileStatement.WhileKeyword,
whileStatement.OpenParenToken,
newCondition,
whileStatement.CloseParenToken,
newBlock);
}
else
{
newNode = DoStatement(
Token(whileStatement.WhileKeyword.LeadingTrivia, SyntaxKind.DoKeyword, whileStatement.CloseParenToken.TrailingTrivia),
newBlock.WithoutTrailingTrivia(),
Token(SyntaxKind.WhileKeyword),
OpenParenToken(),
newCondition,
CloseParenToken(),
SemicolonToken().WithTrailingTrivia(newBlock.GetTrailingTrivia()));
}
break;
}
case DoStatementSyntax doStatement:
{
cancellationToken.ThrowIfCancellationRequested();
if (statements.IsLast(ifStatement))
{
newNode = doStatement.Update(
doStatement.DoKeyword,
newBlock,
doStatement.WhileKeyword,
doStatement.OpenParenToken,
newCondition,
doStatement.CloseParenToken,
doStatement.SemicolonToken);
}
else
{
newNode = WhileStatement(
Token(doStatement.DoKeyword.LeadingTrivia, SyntaxKind.WhileKeyword, SyntaxTriviaList.Empty),
OpenParenToken(),
newCondition,
Token(SyntaxTriviaList.Empty, SyntaxKind.CloseParenToken, doStatement.DoKeyword.TrailingTrivia),
newBlock.WithTrailingTrivia(doStatement.GetTrailingTrivia()));
}
break;
}
default:
{
Debug.Fail(block.Parent.Kind().ToString());
break;
}
}
newNode = newNode.WithFormatterAnnotation();
return(await document.ReplaceNodeAsync(block.Parent, newNode, cancellationToken).ConfigureAwait(false));
}
}
public static async Task <Document> RefactorAsync(
Document document,
ConditionalExpressionSyntax conditionalExpression,
CancellationToken cancellationToken)
{
ConditionalExpressionInfo info = SyntaxInfo.ConditionalExpressionInfo(conditionalExpression);
ExpressionSyntax whenTrue = info.WhenTrue;
ExpressionSyntax whenFalse = info.WhenFalse;
SyntaxKind trueKind = whenTrue.Kind();
SyntaxKind falseKind = whenFalse.Kind();
ExpressionSyntax newNode = null;
if (trueKind == SyntaxKind.TrueLiteralExpression)
{
if (falseKind == SyntaxKind.FalseLiteralExpression)
{
newNode = CreateNewNode(conditionalExpression, info.Condition);
}
else
{
SyntaxTriviaList trailingTrivia = info
.QuestionToken
.LeadingTrivia
.AddRange(info.QuestionToken.TrailingTrivia)
.AddRange(whenTrue.GetLeadingTrivia())
.EmptyIfWhitespace();
newNode = LogicalOrExpression(
conditionalExpression.Condition.Parenthesize().AppendToTrailingTrivia(trailingTrivia),
Token(info.ColonToken.LeadingTrivia, SyntaxKind.BarBarToken, info.ColonToken.TrailingTrivia),
whenFalse.Parenthesize());
}
}
else if (falseKind == SyntaxKind.FalseLiteralExpression)
{
SyntaxTriviaList trailingTrivia = whenTrue
.GetTrailingTrivia()
.AddRange(info.ColonToken.LeadingTrivia)
.AddRange(info.ColonToken.TrailingTrivia)
.AddRange(whenFalse.GetLeadingTrivia())
.EmptyIfWhitespace()
.AddRange(whenFalse.GetTrailingTrivia());
newNode = LogicalAndExpression(
conditionalExpression.Condition.Parenthesize(),
Token(info.QuestionToken.LeadingTrivia, SyntaxKind.AmpersandAmpersandToken, info.QuestionToken.TrailingTrivia),
whenTrue.WithTrailingTrivia(trailingTrivia).Parenthesize());
}
else if (trueKind == SyntaxKind.FalseLiteralExpression &&
falseKind == SyntaxKind.TrueLiteralExpression)
{
SemanticModel semanticModel = await document.GetSemanticModelAsync(cancellationToken).ConfigureAwait(false);
newNode = CreateNewNode(conditionalExpression, Inverter.LogicallyNegate(info.Condition, semanticModel, cancellationToken));
}
newNode = newNode.Parenthesize();
return(await document.ReplaceNodeAsync(conditionalExpression, newNode, cancellationToken).ConfigureAwait(false));
}
public static async Task <Document> InvertIfAsync(
Document document,
IfStatementSyntax ifStatement,
bool recursive = false,
CancellationToken cancellationToken = default(CancellationToken))
{
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 = ifStatement;
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: Inverter.LogicallyNegate(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);
}
}
private static async Task <ExpressionSyntax> CreateNewNodeAsync(
Document document,
BinaryExpressionSyntax binaryExpression,
CancellationToken cancellationToken)
{
ExpressionSyntax left = binaryExpression.Left;
ExpressionSyntax right = binaryExpression.Right;
TextSpan span = TextSpan.FromBounds(left.Span.End, right.SpanStart);
IEnumerable <SyntaxTrivia> trivia = binaryExpression.DescendantTrivia(span);
bool isWhiteSpaceOrEndOfLine = trivia.All(f => f.IsWhitespaceOrEndOfLineTrivia());
SemanticModel semanticModel = await document.GetSemanticModelAsync(cancellationToken).ConfigureAwait(false);
if (CSharpFacts.IsBooleanLiteralExpression(left.Kind()))
{
SyntaxTriviaList leadingTrivia = binaryExpression.GetLeadingTrivia();
if (!isWhiteSpaceOrEndOfLine)
{
leadingTrivia = leadingTrivia.AddRange(trivia);
}
if (right.IsKind(SyntaxKind.LogicalNotExpression))
{
var logicalNot = (PrefixUnaryExpressionSyntax)right;
ExpressionSyntax operand = logicalNot.Operand;
if (semanticModel.GetTypeInfo(operand, cancellationToken).ConvertedType.IsNullableOf(SpecialType.System_Boolean))
{
return(binaryExpression
.WithLeft(Inverter.LogicallyNegate(left, semanticModel, cancellationToken))
.WithRight(operand.WithTriviaFrom(right)));
}
}
return(Inverter.LogicallyNegate(right, semanticModel, cancellationToken)
.WithLeadingTrivia(leadingTrivia));
}
else if (CSharpFacts.IsBooleanLiteralExpression(right.Kind()))
{
SyntaxTriviaList trailingTrivia = binaryExpression.GetTrailingTrivia();
if (!isWhiteSpaceOrEndOfLine)
{
trailingTrivia = trailingTrivia.InsertRange(0, trivia);
}
if (left.IsKind(SyntaxKind.LogicalNotExpression))
{
var logicalNot = (PrefixUnaryExpressionSyntax)left;
ExpressionSyntax operand = logicalNot.Operand;
if (semanticModel.GetTypeInfo(operand, cancellationToken).ConvertedType.IsNullableOf(SpecialType.System_Boolean))
{
return(binaryExpression
.WithLeft(operand.WithTriviaFrom(left))
.WithRight(Inverter.LogicallyNegate(right, semanticModel, cancellationToken)));
}
}
return(Inverter.LogicallyNegate(left, semanticModel, cancellationToken)
.WithTrailingTrivia(trailingTrivia));
}
Debug.Fail(binaryExpression.ToString());
return(binaryExpression);
}
private static ExpressionSyntax GetBooleanExpression(
ExpressionSyntax condition,
ExpressionSyntax expression1,
ExpressionSyntax expression2,
SemanticModel semanticModel,
CancellationToken cancellationToken = default(CancellationToken))
{
switch (expression1.Kind())
{
case SyntaxKind.TrueLiteralExpression:
{
switch (expression2.Kind())
{
case SyntaxKind.TrueLiteralExpression:
return(expression2);
case SyntaxKind.FalseLiteralExpression:
return(condition);
default:
return(LogicalOrExpression(condition, expression2));
}
}
case SyntaxKind.FalseLiteralExpression:
{
switch (expression2.Kind())
{
case SyntaxKind.TrueLiteralExpression:
return(Inverter.LogicallyNegate(condition, semanticModel, cancellationToken));
case SyntaxKind.FalseLiteralExpression:
return(expression2);
default:
return(LogicalAndExpression(Inverter.LogicallyNegate(condition, semanticModel, cancellationToken), expression2));
}
}
default:
{
switch (expression2.Kind())
{
case SyntaxKind.TrueLiteralExpression:
return(LogicalOrExpression(Inverter.LogicallyNegate(condition, semanticModel, cancellationToken), expression1));
case SyntaxKind.FalseLiteralExpression:
return(LogicalAndExpression(condition, expression1));
default:
throw new InvalidOperationException();
}
}
}
BinaryExpressionSyntax LogicalAndExpression(ExpressionSyntax left, ExpressionSyntax right)
{
return(CSharpFactory.LogicalAndExpression(
left.Parenthesize(),
right.Parenthesize()));
}
BinaryExpressionSyntax LogicalOrExpression(ExpressionSyntax left, ExpressionSyntax right)
{
return(CSharpFactory.LogicalOrExpression(
left.Parenthesize(),
right.Parenthesize()));
}
}
