private static IEnumerable <SwitchSectionSyntax> CreateSwitchSections(IfStatementSyntax ifStatement)
{
foreach (SyntaxNode node in IfElseChain.GetChain(ifStatement))
{
if (node.IsKind(SyntaxKind.IfStatement))
{
ifStatement = (IfStatementSyntax)node;
var condition = ifStatement.Condition as BinaryExpressionSyntax;
List <SwitchLabelSyntax> labels = CreateSwitchLabels(condition, new List <SwitchLabelSyntax>());
labels.Reverse();
SwitchSectionSyntax section = SwitchSection(
List(labels),
AddBreakStatementIfNecessary(ifStatement.Statement));
yield return(section);
}
else
{
var elseClause = (ElseClauseSyntax)node;
yield return(DefaultSwitchSection(AddBreakStatementIfNecessary(elseClause.Statement)));
}
}
}
private static HashSet <AwaitExpressionSyntax> GetAwaitExpressionsFromIfStatement(
IfStatementSyntax ifStatement,
bool endsWithElse)
{
HashSet <AwaitExpressionSyntax> awaitExpressions = null;
foreach (IfStatementOrElseClause ifOrElse in IfElseChain.GetChain(ifStatement))
{
if (ifOrElse.IsElse &&
!endsWithElse)
{
return(null);
}
AwaitExpressionSyntax awaitExpression = GetLastReturnAwaitExpressionOfDefault(ifOrElse.Statement);
if (awaitExpression != null)
{
(awaitExpressions ?? (awaitExpressions = new HashSet <AwaitExpressionSyntax>())).Add(awaitExpression);
}
else
{
return(null);
}
}
return(awaitExpressions);
}
private static IEnumerable <SwitchSectionSyntax> CreateSwitchSections(IfStatementSyntax ifStatement)
{
foreach (IfStatementOrElseClause ifOrElse in IfElseChain.GetChain(ifStatement))
{
if (ifOrElse.IsIf)
{
ifStatement = ifOrElse.AsIf();
var condition = ifStatement.Condition as BinaryExpressionSyntax;
List <SwitchLabelSyntax> labels = CreateSwitchLabels(condition, new List <SwitchLabelSyntax>());
labels.Reverse();
SwitchSectionSyntax section = SwitchSection(
List(labels),
AddBreakStatementIfNecessary(ifStatement.Statement));
yield return(section);
}
else
{
yield return(DefaultSwitchSection(AddBreakStatementIfNecessary(ifOrElse.Statement)));
}
}
}
public static BracesAnalysisResult AnalyzeBraces(IfStatementSyntax ifStatement)
{
if (ifStatement == null)
{
throw new ArgumentNullException(nameof(ifStatement));
}
bool anyHasEmbedded = false;
bool anyHasBlock = false;
bool allSupportsEmbedded = true;
int cnt = 0;
foreach (IfStatementOrElseClause ifOrElse in IfElseChain.GetChain(ifStatement))
{
cnt++;
StatementSyntax statement = ifOrElse.Statement;
if (!anyHasEmbedded && !statement.IsKind(SyntaxKind.Block))
{
anyHasEmbedded = true;
}
if (!anyHasBlock && statement.IsKind(SyntaxKind.Block))
{
anyHasBlock = true;
}
if (allSupportsEmbedded && !SupportsEmbedded(statement))
{
allSupportsEmbedded = false;
}
if (cnt > 1 && anyHasEmbedded && !allSupportsEmbedded)
{
return(BracesAnalysisResult.AddBraces);
}
}
if (cnt > 1 &&
allSupportsEmbedded &&
anyHasBlock)
{
if (anyHasEmbedded)
{
return(BracesAnalysisResult.AddBraces | BracesAnalysisResult.RemoveBraces);
}
else
{
return(BracesAnalysisResult.RemoveBraces);
}
}
return(BracesAnalysisResult.None);
}
private static IEnumerable <IfStatementSyntax> GetIfStatements(IfStatementSyntax ifStatement)
{
foreach (IfStatementOrElseClause ifOrElse in IfElseChain.GetChain(ifStatement))
{
if (ifOrElse.IsIf)
{
yield return(ifOrElse.AsIf());
}
}
}
private static IEnumerable <BlockSyntax> GetBlockStatements(IfStatementSyntax ifStatement)
{
foreach (IfStatementOrElseClause ifOrElse in IfElseChain.GetChain(ifStatement))
{
StatementSyntax statement = ifOrElse.Statement;
if (statement?.IsKind(SyntaxKind.Block) == true)
{
yield return((BlockSyntax)statement);
}
}
}
private static IEnumerable <StatementSyntax> GetEmbeddedStatements(IfStatementSyntax topmostIf)
{
foreach (IfStatementOrElseClause ifOrElse in IfElseChain.GetChain(topmostIf))
{
StatementSyntax statement = ifOrElse.Statement;
if (statement?.IsKind(SyntaxKind.Block) == false)
{
yield return(statement);
}
}
}
public static async Task ComputeRefactoringAsync(RefactoringContext context, IfStatementSyntax ifStatement)
{
if (IfElseChain.IsTopmostIf(ifStatement))
{
SemanticModel semanticModel = await context.GetSemanticModelAsync().ConfigureAwait(false);
if (IfElseChain.GetChain(ifStatement)
.Where(f => f.IsKind(SyntaxKind.IfStatement))
.All(f => IsValidIf((IfStatementSyntax)f, semanticModel, context.CancellationToken)))
{
string title = (IfElseChain.IsPartOfChain(ifStatement))
? "Replace if-else with switch"
: "Replace if with switch";
context.RegisterRefactoring(
title,
cancellationToken => RefactorAsync(context.Document, ifStatement, cancellationToken));
}
}
}
private static IEnumerable <StatementSyntax> GetEmbeddedStatements(IfStatementSyntax topmostIf)
{
foreach (SyntaxNode node in IfElseChain.GetChain(topmostIf))
{
switch (node.Kind())
{
case SyntaxKind.IfStatement:
{
var ifStatement = (IfStatementSyntax)node;
StatementSyntax statement = ifStatement.Statement;
if (statement?.IsKind(SyntaxKind.Block) == false)
{
yield return(statement);
}
break;
}
case SyntaxKind.ElseClause:
{
var elseClause = (ElseClauseSyntax)node;
StatementSyntax statement = elseClause.Statement;
if (statement?.IsKind(SyntaxKind.Block) == false)
{
yield return(statement);
}
break;
}
}
}
}