private async Task <Document> GenerateFieldDelegatingConstructorAsync()
{
var arguments = _state.Arguments.ToList();
var parameterTypes = _state.ParameterTypes;
var typeParametersNames = _state.TypeToGenerateIn.GetAllTypeParameters().Select(t => t.Name).ToList();
var parameterNames = _state.AttributeArguments != null
? _service.GenerateParameterNames(_document.SemanticModel, _state.AttributeArguments, typeParametersNames)
: _service.GenerateParameterNames(_document.SemanticModel, arguments, typeParametersNames);
Dictionary <string, ISymbol> parameterToExistingFieldMap;
Dictionary <string, string> parameterToNewFieldMap;
List <IParameterSymbol> parameters;
GetParameters(arguments, _state.AttributeArguments, parameterTypes, parameterNames, out parameterToExistingFieldMap, out parameterToNewFieldMap, out parameters);
var provider = _document.Project.Solution.Workspace.Services.GetLanguageServices(_state.TypeToGenerateIn.Language);
var syntaxFactory = provider.GetService <SyntaxGenerator>();
var codeGenerationService = new CSharpCodeGenerationService(_document.Project.Solution.Workspace);
var syntaxTree = _document.SyntaxTree;
var members = syntaxFactory.CreateFieldDelegatingConstructor(
_state.TypeToGenerateIn.Name, _state.TypeToGenerateIn, parameters,
parameterToExistingFieldMap, parameterToNewFieldMap, _cancellationToken);
var result = await codeGenerationService.AddMembersAsync(
_document.Project.Solution,
_state.TypeToGenerateIn,
members,
new CodeGenerationOptions(_state.Token.GetLocation(), generateDefaultAccessibility : false),
_cancellationToken)
.ConfigureAwait(false);
return(result);
}
protected override async Task <Document> GetChangedDocumentAsync(CancellationToken cancellationToken)
{
// First, see if there are any constructors that would take the first 'n' arguments
// we've provided. If so, delegate to those, and then create a field for any
// remaining arguments. Try to match from largest to smallest.
//
// Otherwise, just generate a normal constructor that assigns any provided
// parameters into fields.
var parameterToExistingFieldMap = new Dictionary <string, ISymbol>();
for (int i = 0; i < _state.Parameters.Count; i++)
{
parameterToExistingFieldMap[_state.Parameters[i].Name] = _state.SelectedMembers[i];
}
var factory = _document.GetLanguageService <SyntaxGenerator>();
var syntaxTree = await _document.GetSyntaxTreeAsync(cancellationToken).ConfigureAwait(false);
var members = factory.CreateFieldDelegatingConstructor(
_state.ContainingType.Name,
_state.ContainingType,
_state.Parameters,
parameterToExistingFieldMap,
parameterToNewFieldMap: null,
cancellationToken: cancellationToken);
var codeGenerationService = new CSharpCodeGenerationService(_document.Project.Solution.Workspace.Services.GetLanguageServices(LanguageNames.CSharp));
var result = await codeGenerationService.AddMembersAsync(
_document.Project.Solution,
_state.ContainingType,
members,
new CodeGenerationOptions(contextLocation : syntaxTree.GetLocation(_state.TextSpan), generateDefaultAccessibility : false),
cancellationToken)
.ConfigureAwait(false);
return(result);
}
private async Task <Document> GenerateDelegatingConstructorAsync(
int argumentCount,
INamedTypeSymbol namedType)
{
if (namedType == null)
{
return(null);
}
// We can't resolve overloads across language.
if (_document.Project.Language != namedType.Language)
{
return(null);
}
var arguments = _state.Arguments.Take(argumentCount).ToList();
var remainingArguments = _state.Arguments.Skip(argumentCount).ToList();
var remainingAttributeArguments = _state.AttributeArguments != null?_state.AttributeArguments.Skip(argumentCount).ToList() : null;
var remainingParameterTypes = _state.ParameterTypes.Skip(argumentCount).ToList();
var instanceConstructors = namedType.InstanceConstructors.Where(IsSymbolAccessible).ToSet();
if (instanceConstructors.IsEmpty())
{
return(null);
}
var delegatedConstructor = _service.GetDelegatingConstructor(_state, _document, argumentCount, namedType, instanceConstructors, _cancellationToken);
if (delegatedConstructor == null)
{
return(null);
}
// There was a best match. Call it directly.
var provider = _document.Project.Solution.Workspace.Services.GetLanguageServices(_state.TypeToGenerateIn.Language);
var syntaxFactory = provider.GetService <SyntaxGenerator>();
var codeGenerationService = new CSharpCodeGenerationService(_document.Project.Solution.Workspace);
// Map the first N parameters to the other constructor in this type. Then
// try to map any further parameters to existing fields. Finally, generate
// new fields if no such parameters exist.
// Find the names of the parameters that will follow the parameters we're
// delegating.
var remainingParameterNames = _service.GenerateParameterNames(
_document.SemanticModel, remainingArguments, delegatedConstructor.Parameters.Select(p => p.Name).ToList());
// Can't generate the constructor if the parameter names we're copying over forcibly
// conflict with any names we generated.
if (delegatedConstructor.Parameters.Select(p => p.Name).Intersect(remainingParameterNames).Any())
{
return(null);
}
// Try to map those parameters to fields.
Dictionary <string, ISymbol> parameterToExistingFieldMap;
Dictionary <string, string> parameterToNewFieldMap;
List <IParameterSymbol> remainingParameters;
this.GetParameters(remainingArguments, remainingAttributeArguments, remainingParameterTypes, remainingParameterNames, out parameterToExistingFieldMap, out parameterToNewFieldMap, out remainingParameters);
var fields = syntaxFactory.CreateFieldsForParameters(remainingParameters, parameterToNewFieldMap);
var assignStatements = syntaxFactory.CreateAssignmentStatements(remainingParameters, parameterToExistingFieldMap, parameterToNewFieldMap);
var allParameters = delegatedConstructor.Parameters.Concat(remainingParameters).ToList();
var isThis = namedType.Equals(_state.TypeToGenerateIn);
var delegatingArguments = syntaxFactory.CreateArguments(delegatedConstructor.Parameters);
var baseConstructorArguments = isThis ? null : delegatingArguments;
var thisConstructorArguments = isThis ? delegatingArguments : null;
var constructor = CodeGenerationSymbolFactory.CreateConstructorSymbol(
attributes: null,
accessibility: Accessibility.Public,
modifiers: default(DeclarationModifiers),
typeName: _state.TypeToGenerateIn.Name,
parameters: allParameters,
statements: assignStatements.ToList(),
baseConstructorArguments: baseConstructorArguments,
thisConstructorArguments: thisConstructorArguments);
var members = new List <ISymbol>(fields)
{
constructor
};
var result = await codeGenerationService.AddMembersAsync(
_document.Project.Solution,
_state.TypeToGenerateIn,
members,
new CodeGenerationOptions(_state.Token.GetLocation(), generateDefaultAccessibility : false),
_cancellationToken)
.ConfigureAwait(false);
return(result);
}
