/// <summary>
/// Adds a parameter to a method.
/// </summary>
/// <param name="newParameterIndex"><see langword="null"/> to add as the final parameter</param>
/// <returns></returns>
public static async Task <Solution> AddParameterAsync(
Document invocationDocument,
IMethodSymbol method,
ITypeSymbol newParameterType,
RefKind refKind,
string parameterName,
int?newParameterIndex,
bool fixAllReferences,
CancellationToken cancellationToken)
{
var solution = invocationDocument.Project.Solution;
var referencedSymbols = fixAllReferences
? await FindMethodDeclarationReferencesAsync(invocationDocument, method, cancellationToken).ConfigureAwait(false)
: method.GetAllMethodSymbolsOfPartialParts();
var anySymbolReferencesNotInSource = referencedSymbols.Any(static symbol => !symbol.IsFromSource());
public async Task <Solution> AddParameterAsync(
Document invocationDocument,
IMethodSymbol method,
ITypeSymbol newParamaterType,
RefKind refKind,
string parameterName,
int?newParameterIndex,
bool fixAllReferences,
CancellationToken cancellationToken)
{
var solution = invocationDocument.Project.Solution;
var referencedSymbols = fixAllReferences
? await FindMethodDeclarationReferences(invocationDocument, method, cancellationToken).ConfigureAwait(false)
: method.GetAllMethodSymbolsOfPartialParts();
var anySymbolReferencesNotInSource = referencedSymbols.Any(symbol => !symbol.IsFromSource());
var locationsInSource = referencedSymbols.Where(symbol => symbol.IsFromSource());
// Indexing Locations[0] is valid because IMethodSymbols have one location at most
// and IsFromSource() tests if there is at least one location.
var locationsByDocument = locationsInSource.ToLookup(declarationLocation
=> solution.GetDocument(declarationLocation.Locations[0].SourceTree));
foreach (var documentLookup in locationsByDocument)
{
var document = documentLookup.Key;
var syntaxFacts = document.GetLanguageService <ISyntaxFactsService>();
var syntaxRoot = await document.GetSyntaxRootAsync(cancellationToken).ConfigureAwait(false);
var editor = new SyntaxEditor(syntaxRoot, solution.Workspace);
var generator = editor.Generator;
foreach (var methodDeclaration in documentLookup)
{
var methodNode = syntaxRoot.FindNode(methodDeclaration.Locations[0].SourceSpan);
var existingParameters = generator.GetParameters(methodNode);
var insertionIndex = newParameterIndex ?? existingParameters.Count;
// if the preceding parameter is optional, the new parameter must also be optional
// see also BC30202 and CS1737
var parameterMustBeOptional = insertionIndex > 0 &&
syntaxFacts.GetDefaultOfParameter(existingParameters[insertionIndex - 1]) != null;
var parameterSymbol = CreateParameterSymbol(
methodDeclaration, newParamaterType, refKind, parameterMustBeOptional, parameterName);
var argumentInitializer = parameterMustBeOptional ? generator.DefaultExpression(newParamaterType) : null;
var parameterDeclaration = generator.ParameterDeclaration(parameterSymbol, argumentInitializer)
.WithAdditionalAnnotations(Formatter.Annotation);
if (anySymbolReferencesNotInSource && methodDeclaration == method)
{
parameterDeclaration = parameterDeclaration.WithAdditionalAnnotations(
ConflictAnnotation.Create(FeaturesResources.Related_method_signatures_found_in_metadata_will_not_be_updated));
}
if (method.MethodKind == MethodKind.ReducedExtension)
{
insertionIndex++;
}
AddParameter(syntaxFacts, editor, methodNode, insertionIndex, parameterDeclaration, cancellationToken);
}
var newRoot = editor.GetChangedRoot();
solution = solution.WithDocumentSyntaxRoot(document.Id, newRoot);
}
return(solution);
}