public static async Task <Document> RefactorAsync(
Document document,
ConditionalExpressionSyntax conditionalExpressionSyntax,
CancellationToken cancellationToken)
{
ConditionalExpressionInfo conditionalExpression;
if (ConditionalExpressionInfo.TryCreate(conditionalExpressionSyntax, out conditionalExpression))
{
SemanticModel semanticModel = await document.GetSemanticModelAsync().ConfigureAwait(false);
NullCheckExpression nullCheck;
if (NullCheckExpression.TryCreate(conditionalExpression.Condition, semanticModel, out nullCheck, cancellationToken))
{
ExpressionSyntax whenNotNull = (nullCheck.IsCheckingNotNull)
? conditionalExpression.WhenTrue
: conditionalExpression.WhenFalse;
ExpressionSyntax whenNull = (nullCheck.IsCheckingNull)
? conditionalExpression.WhenTrue
: conditionalExpression.WhenFalse;
ExpressionSyntax expression = FindExpressionThatCanBeConditionallyAccessed(nullCheck.Expression, whenNotNull);
ExpressionSyntax newNode;
if (expression.Parent == whenNotNull &&
whenNotNull.IsKind(SyntaxKind.SimpleMemberAccessExpression) &&
SemanticUtilities.IsPropertyOfNullableOfT(whenNotNull, "Value", semanticModel, cancellationToken))
{
newNode = expression;
}
else
{
newNode = SyntaxFactory.ParseExpression(whenNotNull.ToString().Insert(expression.Span.End - whenNotNull.SpanStart, "?"));
}
if (!semanticModel.GetTypeSymbol(whenNotNull, cancellationToken).IsReferenceType)
{
newNode = CSharpFactory.CoalesceExpression(newNode.Parenthesize(), whenNull.Parenthesize());
}
newNode = newNode
.WithTriviaFrom(conditionalExpressionSyntax)
.Parenthesize();
return(await document.ReplaceNodeAsync(conditionalExpressionSyntax, newNode, cancellationToken).ConfigureAwait(false));
}
}
Debug.Fail(conditionalExpressionSyntax.ToString());
return(document);
}