public sealed override async Task RegisterCodeFixesAsync(CodeFixContext context)
{
if (!Settings.IsCodeFixEnabled(CodeFixIdentifiers.AddCastExpression))
{
return;
}
SyntaxNode root = await context.GetSyntaxRootAsync().ConfigureAwait(false);
ConditionalExpressionSyntax conditionalExpression = root
.FindNode(context.Span, getInnermostNodeForTie: true)?
.FirstAncestorOrSelf <ConditionalExpressionSyntax>();
Debug.Assert(conditionalExpression != null, $"{nameof(conditionalExpression)} is null");
if (conditionalExpression == null)
{
return;
}
foreach (Diagnostic diagnostic in context.Diagnostics)
{
switch (diagnostic.Id)
{
case CompilerDiagnosticIdentifiers.TypeOfConditionalExpressionCannotBeDetermined:
{
ExpressionSyntax whenTrue = conditionalExpression.WhenTrue;
ExpressionSyntax whenFalse = conditionalExpression.WhenFalse;
if (whenTrue?.IsMissing == false &&
whenFalse?.IsMissing == false)
{
SemanticModel semanticModel = await context.GetSemanticModelAsync().ConfigureAwait(false);
ITypeSymbol falseType = semanticModel.GetTypeSymbol(whenFalse, context.CancellationToken);
if (falseType?.IsErrorType() == false)
{
ITypeSymbol destinationType = FindDestinationType(whenTrue, falseType.BaseType, semanticModel);
if (destinationType != null)
{
CodeAction codeAction = CodeAction.Create(
$"Cast to '{SymbolDisplay.GetMinimalString(destinationType, semanticModel, whenTrue.SpanStart)}'",
cancellationToken => AddCastExpressionRefactoring.RefactorAsync(context.Document, whenTrue, destinationType, semanticModel, cancellationToken),
GetEquivalenceKey(diagnostic));
context.RegisterCodeFix(codeAction, diagnostic);
}
}
}
break;
}
}
}
}
public static void AddCastExpression(
CodeFixContext context,
Diagnostic diagnostic,
ExpressionSyntax expression,
ITypeSymbol destinationType,
SemanticModel semanticModel)
{
string typeName = SymbolDisplay.GetMinimalString(destinationType, semanticModel, expression.SpanStart);
TypeSyntax newType = SyntaxFactory.ParseTypeName(typeName);
CodeAction codeAction = CodeAction.Create(
$"Cast to '{typeName}'",
cancellationToken => AddCastExpressionRefactoring.RefactorAsync(context.Document, expression, newType, cancellationToken),
EquivalenceKeyProvider.GetEquivalenceKey(diagnostic, CodeFixIdentifiers.AddCastExpression));
context.RegisterCodeFix(codeAction, diagnostic);
}