public static async Task ComputeRefactoringsAsync(RefactoringContext context, IfStatementSyntax ifStatement)
{
if (context.IsAnyRefactoringEnabled(
RefactoringIdentifiers.SwapStatementsInIfElse,
RefactoringIdentifiers.ReplaceIfElseWithAssignment,
RefactoringIdentifiers.ReplaceIfStatementWithReturnStatement,
RefactoringIdentifiers.ReplaceIfElseWithSwitch) &&
IfElseChain.IsTopmostIf(ifStatement) &&
context.Span.IsBetweenSpans(ifStatement))
{
if (context.IsRefactoringEnabled(RefactoringIdentifiers.ReplaceIfStatementWithReturnStatement))
{
await ReplaceIfWithStatementRefactoring.ComputeRefactoringAsync(context, ifStatement).ConfigureAwait(false);
}
if (context.IsRefactoringEnabled(RefactoringIdentifiers.ReplaceIfElseWithAssignment))
{
ReplaceIfElseWithAssignmentRefactoring.ComputeRefactoring(context, ifStatement);
}
if (context.IsRefactoringEnabled(RefactoringIdentifiers.SwapStatementsInIfElse))
{
SwapStatementInIfElseRefactoring.ComputeRefactoring(context, ifStatement);
}
if (context.IsRefactoringEnabled(RefactoringIdentifiers.ReplaceIfElseWithSwitch))
{
await ReplaceIfElseWithSwitchRefactoring.ComputeRefactoringAsync(context, ifStatement).ConfigureAwait(false);
}
}
}
private static bool CheckContainingNode(SyntaxNode node)
{
switch (node.Kind())
{
case SyntaxKind.ForEachStatement:
case SyntaxKind.ForStatement:
case SyntaxKind.UsingStatement:
case SyntaxKind.WhileStatement:
case SyntaxKind.DoStatement:
case SyntaxKind.LockStatement:
case SyntaxKind.FixedStatement:
case SyntaxKind.UnsafeStatement:
case SyntaxKind.TryStatement:
case SyntaxKind.CheckedStatement:
case SyntaxKind.UncheckedStatement:
return(true);
case SyntaxKind.IfStatement:
return(IfElseChain.IsTopmostIf((IfStatementSyntax)node));
case SyntaxKind.ElseClause:
return(IfElseChain.IsEndOfChain((ElseClauseSyntax)node));
}
return(false);
}
public static bool CanRefactor(
IfStatementSyntax ifStatement,
SemanticModel semanticModel,
CancellationToken cancellationToken = default(CancellationToken))
{
if (IfElseChain.IsTopmostIf(ifStatement))
{
ElseClauseSyntax elseClause = ifStatement.Else;
if (elseClause != null)
{
ExpressionSyntax condition = ifStatement.Condition;
if (condition != null)
{
ITypeSymbol typeSymbol = semanticModel.GetTypeSymbol(condition, cancellationToken);
if (typeSymbol?.IsBoolean() == true)
{
AssignmentExpressionSyntax trueExpression = GetSimpleAssignmentExpression(ifStatement.Statement);
ExpressionSyntax trueRight = trueExpression?.Right;
if (trueRight?.IsBooleanLiteralExpression() == true)
{
AssignmentExpressionSyntax falseExpression = GetSimpleAssignmentExpression(elseClause.Statement);
ExpressionSyntax falseRight = falseExpression?.Right;
if (falseRight?.IsBooleanLiteralExpression() == true)
{
var trueBooleanLiteral = (LiteralExpressionSyntax)trueRight;
var falseBooleanLiteral = (LiteralExpressionSyntax)falseRight;
if (trueBooleanLiteral.IsKind(SyntaxKind.TrueLiteralExpression) != falseBooleanLiteral.IsKind(SyntaxKind.TrueLiteralExpression) &&
trueExpression.Left?.IsEquivalentTo(falseExpression.Left, topLevel: false) == true)
{
return(true);
}
}
}
}
}
}
}
return(false);
}
public static async Task ComputeRefactoringAsync(RefactoringContext context, IfStatementSyntax ifStatement)
{
if (IfElseChain.IsTopmostIf(ifStatement))
{
SemanticModel semanticModel = await context.GetSemanticModelAsync().ConfigureAwait(false);
if (GetIfStatements(ifStatement)
.All(f => IsValidIf(f, semanticModel, context.CancellationToken)))
{
string title = (ifStatement.IsSimpleIf())
? "Replace if with switch"
: "Replace if-else with switch";
context.RegisterRefactoring(
title,
cancellationToken => RefactorAsync(context.Document, ifStatement, cancellationToken));
}
}
}
public static async Task ComputeRefactoringsAsync(RefactoringContext context, IfStatementSyntax ifStatement)
{
if (context.IsAnyRefactoringEnabled(
RefactoringIdentifiers.UseCoalesceExpressionInsteadOfIf,
RefactoringIdentifiers.UseConditionalExpressionInsteadOfIf,
RefactoringIdentifiers.SimplifyIf,
RefactoringIdentifiers.SwapStatementsInIfElse,
RefactoringIdentifiers.ReplaceIfElseWithSwitch) &&
IfElseChain.IsTopmostIf(ifStatement) &&
context.Span.IsBetweenSpans(ifStatement))
{
if (context.IsAnyRefactoringEnabled(
RefactoringIdentifiers.UseCoalesceExpressionInsteadOfIf,
RefactoringIdentifiers.UseConditionalExpressionInsteadOfIf,
RefactoringIdentifiers.SimplifyIf))
{
SemanticModel semanticModel = await context.GetSemanticModelAsync().ConfigureAwait(false);
var options = new IfAnalysisOptions(
useCoalesceExpression: context.IsRefactoringEnabled(RefactoringIdentifiers.UseCoalesceExpressionInsteadOfIf),
useConditionalExpression: context.IsRefactoringEnabled(RefactoringIdentifiers.UseConditionalExpressionInsteadOfIf),
useBooleanExpression: context.IsRefactoringEnabled(RefactoringIdentifiers.SimplifyIf));
foreach (IfRefactoring refactoring in IfRefactoring.Analyze(ifStatement, options, semanticModel, context.CancellationToken))
{
context.RegisterRefactoring(
refactoring.Title,
cancellationToken => refactoring.RefactorAsync(context.Document, cancellationToken));
}
}
if (context.IsRefactoringEnabled(RefactoringIdentifiers.SwapStatementsInIfElse))
{
SwapStatementInIfElseRefactoring.ComputeRefactoring(context, ifStatement);
}
if (context.IsRefactoringEnabled(RefactoringIdentifiers.ReplaceIfElseWithSwitch))
{
await ReplaceIfElseWithSwitchRefactoring.ComputeRefactoringAsync(context, ifStatement).ConfigureAwait(false);
}
}
}
public static void ComputeRefactoring(RefactoringContext context, IfStatementSyntax ifStatement)
{
if (IfElseChain.IsTopmostIf(ifStatement))
{
ElseClauseSyntax elseClause = ifStatement.Else;
if (elseClause != null)
{
StatementSyntax statement1 = ReplaceIfWithStatementRefactoring.GetStatement(ifStatement);
if (statement1?.IsKind(SyntaxKind.ExpressionStatement) == true)
{
StatementSyntax statement2 = ReplaceIfWithStatementRefactoring.GetStatement(elseClause);
if (statement2?.IsKind(SyntaxKind.ExpressionStatement) == true)
{
var expressionStatement1 = (ExpressionStatementSyntax)statement1;
var expressionStatement2 = (ExpressionStatementSyntax)statement2;
ExpressionSyntax expression1 = expressionStatement1.Expression;
if (expression1?.IsKind(SyntaxKind.SimpleAssignmentExpression) == true)
{
ExpressionSyntax expression2 = expressionStatement2.Expression;
if (expression2?.IsKind(SyntaxKind.SimpleAssignmentExpression) == true)
{
var assignment1 = (AssignmentExpressionSyntax)expression1;
var assignment2 = (AssignmentExpressionSyntax)expression2;
ExpressionSyntax left1 = assignment1.Left;
ExpressionSyntax right1 = assignment1.Right;
if (left1?.IsMissing == false &&
right1?.IsMissing == false)
{
ExpressionSyntax left2 = assignment2.Left;
ExpressionSyntax right2 = assignment2.Right;
if (left2?.IsMissing == false &&
right2?.IsMissing == false &&
left1.IsEquivalentTo(left2, topLevel: false))
{
context.RegisterRefactoring(
"Replace if-else with assignment",
cancellationToken =>
{
return(RefactorAsync(
context.Document,
ifStatement,
left1,
right1,
right2,
cancellationToken));
});
}
}
}
}
}
}
}
}
}
private static StatementSyntax GetStatement(
RefactoringContext context,
BlockSyntax block,
SyntaxNode parent)
{
switch (parent?.Kind())
{
case SyntaxKind.WhileStatement:
case SyntaxKind.DoStatement:
case SyntaxKind.ForStatement:
case SyntaxKind.ForEachStatement:
case SyntaxKind.FixedStatement:
case SyntaxKind.CheckedStatement:
case SyntaxKind.UncheckedStatement:
case SyntaxKind.UnsafeStatement:
case SyntaxKind.UsingStatement:
case SyntaxKind.LockStatement:
{
if (block.OpenBraceToken.Span.Contains(context.Span) ||
block.CloseBraceToken.Span.Contains(context.Span))
{
if (parent.IsKind(SyntaxKind.UsingStatement))
{
var usingStatement = (UsingStatementSyntax)parent;
while (usingStatement.IsParentKind(SyntaxKind.UsingStatement))
{
usingStatement = (UsingStatementSyntax)usingStatement.Parent;
}
return(usingStatement);
}
return((StatementSyntax)parent);
}
break;
}
case SyntaxKind.TryStatement:
{
var tryStatement = (TryStatementSyntax)parent;
if (tryStatement.Block?.OpenBraceToken.Span.Contains(context.Span) == true)
{
return((StatementSyntax)parent);
}
break;
}
case SyntaxKind.IfStatement:
{
var ifStatement = (IfStatementSyntax)parent;
if (IfElseChain.IsTopmostIf(ifStatement) &&
block.OpenBraceToken.Span.Contains(context.Span))
{
return(ifStatement);
}
if (ifStatement.Else == null &&
block.CloseBraceToken.Span.Contains(context.Span))
{
return(ifStatement);
}
break;
}
case SyntaxKind.ElseClause:
{
var elseClause = (ElseClauseSyntax)parent;
if (block.CloseBraceToken.Span.Contains(context.Span))
{
return(IfElseChain.GetTopmostIf(elseClause));
}
break;
}
case SyntaxKind.CatchClause:
{
var catchClause = (CatchClauseSyntax)parent;
if (catchClause.IsParentKind(SyntaxKind.TryStatement))
{
var tryStatement = (TryStatementSyntax)catchClause.Parent;
if (tryStatement.Finally == null &&
catchClause.Block?.CloseBraceToken.Span.Contains(context.Span) == true)
{
return(tryStatement);
}
}
break;
}
case SyntaxKind.FinallyClause:
{
var finallyClause = (FinallyClauseSyntax)parent;
if (finallyClause.IsParentKind(SyntaxKind.TryStatement))
{
var tryStatement = (TryStatementSyntax)finallyClause.Parent;
if (finallyClause.Block?.CloseBraceToken.Span.Contains(context.Span) == true)
{
return(tryStatement);
}
}
break;
}
}
return(null);
}
public static ImmutableArray <IfRefactoring> Analyze(
IfStatementSyntax ifStatement,
IfAnalysisOptions options,
SemanticModel semanticModel,
CancellationToken cancellationToken = default(CancellationToken))
{
if (IfElseChain.IsTopmostIf(ifStatement))
{
ExpressionSyntax condition = ifStatement.Condition;
if (condition != null)
{
ElseClauseSyntax elseClause = ifStatement.Else;
if (elseClause != null)
{
if (options.CheckSpanDirectives(ifStatement))
{
StatementSyntax statement1 = ifStatement.GetSingleStatementOrDefault();
if (statement1 != null)
{
SyntaxKind kind1 = statement1.Kind();
if (kind1 == SyntaxKind.ExpressionStatement ||
kind1 == SyntaxKind.ReturnStatement ||
kind1 == SyntaxKind.YieldReturnStatement)
{
StatementSyntax statement2 = elseClause.GetSingleStatementOrDefault();
if (statement2?.IsKind(kind1) == true)
{
switch (kind1)
{
case SyntaxKind.ExpressionStatement:
{
return(Analyze(ifStatement, condition, (ExpressionStatementSyntax)statement1, (ExpressionStatementSyntax)statement2, options));
}
case SyntaxKind.ReturnStatement:
{
return(Analyze(ifStatement, condition, ((ReturnStatementSyntax)statement1).Expression, ((ReturnStatementSyntax)statement2).Expression, semanticModel, cancellationToken, options, isYield: false));
}
case SyntaxKind.YieldReturnStatement:
{
return(Analyze(ifStatement, condition, ((YieldStatementSyntax)statement1).Expression, ((YieldStatementSyntax)statement2).Expression, semanticModel, cancellationToken, options, isYield: true));
}
}
}
}
}
}
}
else
{
StatementSyntax nextStatement = ifStatement.NextStatement();
if (nextStatement?.IsKind(SyntaxKind.ReturnStatement) == true)
{
return(Analyze(ifStatement, (ReturnStatementSyntax)nextStatement, options, semanticModel, cancellationToken));
}
}
}
}
return(ImmutableArray <IfRefactoring> .Empty);
}
