private static ImmutableArray <IfRefactoring> Analyze(
IfStatementSyntax ifStatement,
ExpressionSyntax condition,
ExpressionSyntax expression1,
ExpressionSyntax expression2,
SemanticModel semanticModel,
CancellationToken cancellationToken,
IfAnalysisOptions options,
bool isYield)
{
if (expression1?.IsMissing == false &&
expression2?.IsMissing == false)
{
if (options.UseCoalesceExpression)
{
NullCheckExpression nullCheck;
if (NullCheckExpression.TryCreate(condition, semanticModel, out nullCheck, cancellationToken))
{
IfRefactoring refactoring = CreateIfToReturnWithCoalesceExpression(
ifStatement,
(nullCheck.IsCheckingNull) ? expression2 : expression1,
(nullCheck.IsCheckingNull) ? expression1 : expression2,
nullCheck,
isYield,
semanticModel,
cancellationToken);
if (refactoring != null)
{
return(refactoring.ToImmutableArray());
}
}
}
IfToReturnWithBooleanExpression ifToReturnWithBooleanExpression = null;
if (options.UseBooleanExpression &&
(expression1.IsBooleanLiteralExpression() || expression2.IsBooleanLiteralExpression()) &&
semanticModel.GetTypeSymbol(expression1, cancellationToken)?.IsBoolean() == true &&
semanticModel.GetTypeSymbol(expression2, cancellationToken)?.IsBoolean() == true)
{
ifToReturnWithBooleanExpression = IfToReturnWithBooleanExpression.Create(ifStatement, expression1, expression2, isYield);
}
IfToReturnWithConditionalExpression ifToReturnWithConditionalExpression = null;
if (options.UseConditionalExpression &&
(!expression1.IsBooleanLiteralExpression() || !expression2.IsBooleanLiteralExpression()))
{
ifToReturnWithConditionalExpression = IfToReturnWithConditionalExpression.Create(ifStatement, expression1, expression2, isYield);
}
return(ToImmutableArray(ifToReturnWithBooleanExpression, ifToReturnWithConditionalExpression));
}
return(ImmutableArray <IfRefactoring> .Empty);
}
private static ImmutableArray <IfRefactoring> Analyze(
IfStatementSyntax ifStatement,
ExpressionSyntax condition,
ExpressionSyntax expression1,
ExpressionSyntax expression2,
IfAnalysisOptions options,
bool isYield,
SemanticModel semanticModel,
CancellationToken cancellationToken)
{
if (expression1?.IsMissing != false)
{
return(Empty);
}
if (expression2?.IsMissing != false)
{
return(Empty);
}
if (options.UseCoalesceExpression ||
options.UseExpression)
{
SyntaxKind kind1 = expression1.Kind();
SyntaxKind kind2 = expression2.Kind();
if (kind1.IsBooleanLiteralExpression() &&
kind2.IsBooleanLiteralExpression() &&
kind1 != kind2)
{
if (options.UseExpression)
{
if (ifStatement.IsSimpleIf() &&
(ifStatement.PreviousStatementOrDefault() is IfStatementSyntax previousIf) &&
previousIf.IsSimpleIf() &&
(previousIf.GetSingleStatementOrDefault() is ReturnStatementSyntax returnStatement) &&
returnStatement.Expression?.WalkDownParentheses().Kind() == kind1)
{
return(Empty);
}
return(new IfToReturnWithExpression(ifStatement, condition, isYield, negate: kind1 == SyntaxKind.FalseLiteralExpression).ToImmutableArray());
}
return(Empty);
}
NullCheckExpressionInfo nullCheck = SyntaxInfo.NullCheckExpressionInfo(condition, semanticModel: semanticModel, cancellationToken: cancellationToken);
if (nullCheck.Success)
{
IfRefactoring refactoring = CreateIfToReturnStatement(
ifStatement,
(nullCheck.IsCheckingNull) ? expression2 : expression1,
(nullCheck.IsCheckingNull) ? expression1 : expression2,
nullCheck,
options,
isYield,
semanticModel,
cancellationToken);
if (refactoring != null)
{
return(refactoring.ToImmutableArray());
}
}
}
IfToReturnWithBooleanExpression ifToReturnWithBooleanExpression = null;
if (options.UseBooleanExpression &&
(expression1.Kind().IsBooleanLiteralExpression() || expression2.Kind().IsBooleanLiteralExpression()) &&
semanticModel.GetTypeSymbol(expression1, cancellationToken)?.IsBoolean() == true &&
semanticModel.GetTypeSymbol(expression2, cancellationToken)?.IsBoolean() == true)
{
ifToReturnWithBooleanExpression = IfToReturnWithBooleanExpression.Create(ifStatement, expression1, expression2, isYield);
}
IfToReturnWithConditionalExpression ifToReturnWithConditionalExpression = null;
if (options.UseConditionalExpression &&
(!expression1.Kind().IsBooleanLiteralExpression() || !expression2.Kind().IsBooleanLiteralExpression()))
{
ifToReturnWithConditionalExpression = IfToReturnWithConditionalExpression.Create(ifStatement, expression1, expression2, isYield);
}
return(ToImmutableArray(ifToReturnWithBooleanExpression, ifToReturnWithConditionalExpression));
}
private static ImmutableArray <IfRefactoring> Analyze(
IfStatementSyntax ifStatement,
ExpressionSyntax condition,
ExpressionSyntax expression1,
ExpressionSyntax expression2,
SemanticModel semanticModel,
CancellationToken cancellationToken,
IfAnalysisOptions options,
bool isYield)
{
if (expression1?.IsMissing == false &&
expression2?.IsMissing == false)
{
if (options.UseCoalesceExpression)
{
SyntaxKind conditionKind = condition.Kind();
if (conditionKind == SyntaxKind.EqualsExpression)
{
var binaryExpression = (BinaryExpressionSyntax)condition;
if (IsNullLiteral(binaryExpression.Right) &&
IsEquivalent(binaryExpression.Left, expression2))
{
return(IfToReturnWithCoalesceExpression.Create(ifStatement, expression2, expression1, isYield).ToImmutableArray());
}
}
else if (conditionKind == SyntaxKind.NotEqualsExpression)
{
var binaryExpression = (BinaryExpressionSyntax)condition;
if (IsNullLiteral(binaryExpression.Right) &&
IsEquivalent(binaryExpression.Left, expression1))
{
return(IfToReturnWithCoalesceExpression.Create(ifStatement, expression1, expression2, isYield).ToImmutableArray());
}
}
}
IfToReturnWithBooleanExpression ifToReturnWithBooleanExpression = null;
if (options.UseBooleanExpression &&
semanticModel.GetTypeSymbol(expression1, cancellationToken)?.IsBoolean() == true &&
semanticModel.GetTypeSymbol(expression2, cancellationToken)?.IsBoolean() == true)
{
ifToReturnWithBooleanExpression = IfToReturnWithBooleanExpression.Create(ifStatement, expression1, expression2, isYield);
}
IfToReturnWithConditionalExpression ifToReturnWithConditionalExpression = null;
if (options.UseConditionalExpression &&
(!expression1.IsBooleanLiteralExpression() || !expression2.IsBooleanLiteralExpression()))
{
ifToReturnWithConditionalExpression = IfToReturnWithConditionalExpression.Create(ifStatement, expression1, expression2, isYield);
}
return(ToImmutableArray(ifToReturnWithBooleanExpression, ifToReturnWithConditionalExpression));
}
return(ImmutableArray <IfRefactoring> .Empty);
}