private static bool TryGetParameterName(ISymbol member, TypeDeclarationSyntax typeDeclaration, SemanticModel semanticModel, CancellationToken cancellationToken, out string parameterName)
{
parameterName = null;
using (var walker = AssignmentExecutionWalker.For(member, typeDeclaration, Scope.Member, semanticModel, cancellationToken))
{
foreach (var assignment in walker.Assignments)
{
if (assignment.Right is IdentifierNameSyntax identifierName &&
assignment.TryFirstAncestor <ConstructorDeclarationSyntax>(out var ctor) &&
ctor.TryFindParameter(identifierName.Identifier.ValueText, out _))
{
if (parameterName == null)
{
parameterName = identifierName.Identifier.ValueText;
}
else if (parameterName != identifierName.Identifier.ValueText)
{
parameterName = null;
return(false);
}
}
}
}
return(parameterName != null);
}
public static void FieldPrivateCtorCalledByInitializer(SearchScope scope)
{
var code = @"
namespace N
{
internal class C
{
public static readonly C Default = new C();
private readonly int value;
private C()
{
this.value = 1;
}
}
}";
var syntaxTree = CSharpSyntaxTree.ParseText(code);
var compilation = CSharpCompilation.Create("test", new[] { syntaxTree }, MetadataReferences.FromAttributes());
var semanticModel = compilation.GetSemanticModel(syntaxTree);
var field = semanticModel.GetDeclaredSymbolSafe(syntaxTree.FindFieldDeclaration("private readonly int value"), CancellationToken.None);
var bar = syntaxTree.FindTypeDeclaration("C");
Assert.AreEqual(true, AssignmentExecutionWalker.FirstFor(field, bar, scope, semanticModel, CancellationToken.None, out var result));
Assert.AreEqual("this.value = 1", result.ToString());
Assert.AreEqual(true, AssignmentExecutionWalker.SingleFor(field, bar, scope, semanticModel, CancellationToken.None, out result));
Assert.AreEqual("this.value = 1", result.ToString());
using (var walker = AssignmentExecutionWalker.For(field, bar, scope, semanticModel, CancellationToken.None))
{
Assert.AreEqual("this.value = 1", walker.Assignments.Single().ToString());
}
}
public static void FieldWithCtorArg(SearchScope scope)
{
var code = @"
namespace N
{
internal class C
{
private readonly int value;
internal C(int arg)
{
this.value = arg;
}
}
}";
var syntaxTree = CSharpSyntaxTree.ParseText(code);
var compilation = CSharpCompilation.Create("test", new[] { syntaxTree }, MetadataReferences.FromAttributes());
var semanticModel = compilation.GetSemanticModel(syntaxTree);
var value = syntaxTree.FindMemberAccessExpression("this.value");
var ctor = syntaxTree.FindConstructorDeclaration("C(int arg)");
var field = semanticModel.GetSymbolSafe(value, CancellationToken.None);
Assert.AreEqual(true, AssignmentExecutionWalker.FirstFor(field, ctor, scope, semanticModel, CancellationToken.None, out var result));
Assert.AreEqual("this.value = arg", result.ToString());
Assert.AreEqual(true, AssignmentExecutionWalker.SingleFor(field, ctor, scope, semanticModel, CancellationToken.None, out result));
Assert.AreEqual("this.value = arg", result.ToString());
using (var walker = AssignmentExecutionWalker.For(field, ctor, scope, semanticModel, CancellationToken.None))
{
Assert.AreEqual("this.value = arg", walker.Assignments.Single().ToString());
}
}
private static bool TryGetParameterName(ISymbol member, TypeDeclarationSyntax typeDeclaration, SemanticModel semanticModel, CancellationToken cancellationToken, [NotNullWhen(true)] out string?parameterName)
{
using (var walker = AssignmentExecutionWalker.For(member, typeDeclaration, SearchScope.Member, semanticModel, cancellationToken))
{
foreach (var assignment in walker.Assignments)
{
if (assignment.Right is IdentifierNameSyntax {
Identifier: { } identifier
} &&
public void FieldWithCtorArgViaProperty(Scope scope)
{
var testCode = @"
namespace RoslynSandbox
{
internal class Foo
{
private int number;
internal Foo(int arg)
{
this.Number = arg;
}
public int Number
{
get { return this.number; }
set { this.number = value; }
}
}
}";
var syntaxTree = CSharpSyntaxTree.ParseText(testCode);
var compilation = CSharpCompilation.Create("test", new[] { syntaxTree }, MetadataReferences.FromAttributes());
var semanticModel = compilation.GetSemanticModel(syntaxTree);
var value = syntaxTree.FindMemberAccessExpression("this.number");
var ctor = syntaxTree.FindConstructorDeclaration("Foo(int arg)");
AssignmentExpressionSyntax result;
var field = semanticModel.GetSymbolSafe(value, CancellationToken.None);
if (scope != Scope.Member)
{
Assert.AreEqual(true, AssignmentExecutionWalker.FirstFor(field, ctor, scope, semanticModel, CancellationToken.None, out result));
Assert.AreEqual("this.number = value", result.ToString());
Assert.AreEqual(true, AssignmentExecutionWalker.SingleFor(field, ctor, scope, semanticModel, CancellationToken.None, out result));
Assert.AreEqual("this.number = value", result.ToString());
using (var walker = AssignmentExecutionWalker.For(field, ctor, scope, semanticModel, CancellationToken.None))
{
Assert.AreEqual("this.number = value", walker.Assignments.Single().ToString());
}
}
else
{
Assert.AreEqual(false, AssignmentExecutionWalker.FirstFor(field, ctor, scope, semanticModel, CancellationToken.None, out result));
}
}
public static void FieldInPropertyExpressionBody(SearchScope scope)
{
var code = @"
namespace N
{
internal class C
{
private int number;
internal C()
{
var i = this.Number;
}
public int Number => this.number = 3;
}
}";
var syntaxTree = CSharpSyntaxTree.ParseText(code);
var compilation = CSharpCompilation.Create("test", new[] { syntaxTree }, MetadataReferences.FromAttributes());
var semanticModel = compilation.GetSemanticModel(syntaxTree);
var value = syntaxTree.FindMemberAccessExpression("this.number");
var ctor = syntaxTree.FindConstructorDeclaration("C()");
AssignmentExpressionSyntax result;
var field = semanticModel.GetSymbolSafe(value, CancellationToken.None);
if (scope != SearchScope.Member)
{
Assert.AreEqual(true, AssignmentExecutionWalker.FirstFor(field, ctor, scope, semanticModel, CancellationToken.None, out result));
Assert.AreEqual("this.number = 3", result.ToString());
Assert.AreEqual(true, AssignmentExecutionWalker.SingleFor(field, ctor, scope, semanticModel, CancellationToken.None, out result));
Assert.AreEqual("this.number = 3", result.ToString());
using (var walker = AssignmentExecutionWalker.For(field, ctor, scope, semanticModel, CancellationToken.None))
{
Assert.AreEqual("this.number = 3", walker.Assignments.Single().ToString());
}
}
else
{
Assert.AreEqual(false, AssignmentExecutionWalker.FirstFor(field, ctor, scope, semanticModel, CancellationToken.None, out _));
}
}
internal static bool IsValueValidForRegisteredType(ExpressionSyntax value, ITypeSymbol registeredType, SemanticModel semanticModel, CancellationToken cancellationToken, PooledSet <SyntaxNode>?visited = null)
{
switch (value)
{
case ConditionalExpressionSyntax conditional:
return(IsValueValidForRegisteredType(conditional.WhenTrue, registeredType, semanticModel, cancellationToken, visited) &&
IsValueValidForRegisteredType(conditional.WhenFalse, registeredType, semanticModel, cancellationToken, visited));
case BinaryExpressionSyntax binary when binary.IsKind(SyntaxKind.CoalesceExpression):
return(IsValueValidForRegisteredType(binary.Left, registeredType, semanticModel, cancellationToken, visited) &&
IsValueValidForRegisteredType(binary.Right, registeredType, semanticModel, cancellationToken, visited));
}
if (registeredType.TypeKind == TypeKind.Enum)
{
return(semanticModel.TryGetType(value, cancellationToken, out var valueType) &&
valueType.MetadataName == registeredType.MetadataName &&
Equals(valueType.ContainingType, registeredType.ContainingType) &&
NamespaceSymbolComparer.Equals(valueType.ContainingNamespace, registeredType.ContainingNamespace));
}
if (semanticModel.IsRepresentationPreservingConversion(value, registeredType))
{
return(true);
}
if (semanticModel.TryGetSymbol(value, cancellationToken, out var symbol))
{
if (symbol is IFieldSymbol field)
{
if (field.TrySingleDeclaration(cancellationToken, out var fieldDeclaration))
{
if (fieldDeclaration.Declaration is { } variableDeclaration&&
variableDeclaration.Variables.TryLast(out var variable) &&
variable.Initializer is { } initializer&&
!IsValueValidForRegisteredType(initializer.Value, registeredType, semanticModel, cancellationToken, visited))
{
return(false);
}
return(IsAssignedValueOfRegisteredType(symbol, fieldDeclaration));
}
return(field.Type == KnownSymbols.Object);
}
if (symbol is IPropertySymbol property)
{
if (property.TrySingleDeclaration(cancellationToken, out PropertyDeclarationSyntax? propertyDeclaration))
{
if (propertyDeclaration.Initializer is { } initializer&&
!IsValueValidForRegisteredType(initializer.Value, registeredType, semanticModel, cancellationToken, visited))
{
return(false);
}
if (property.SetMethod == null &&
property.GetMethod is { } getMethod)
{
return(IsReturnValueOfRegisteredType(getMethod));
}
return(IsAssignedValueOfRegisteredType(symbol, propertyDeclaration));
}
return(property.Type == KnownSymbols.Object);
}
if (symbol is IMethodSymbol method)
{
return(IsReturnValueOfRegisteredType(method));
}
}
return(false);
bool IsAssignedValueOfRegisteredType(ISymbol memberSymbol, MemberDeclarationSyntax declaration)
{
if (declaration.TryFirstAncestor(out TypeDeclarationSyntax? typeDeclaration))
{
using (var walker = AssignmentExecutionWalker.For(memberSymbol, typeDeclaration, SearchScope.Type, semanticModel, cancellationToken))
{
foreach (var assignment in walker.Assignments)
{
if (!IsValueValidForRegisteredType(assignment.Right, registeredType, semanticModel, cancellationToken, visited))
{
return(false);
}
}
}
}
return(true);
}
bool IsReturnValueOfRegisteredType(IMethodSymbol method)
{
if (method.TrySingleMethodDeclaration(cancellationToken, out var target))
{
#pragma warning disable IDISP003 // Dispose previous before re-assigning.
using (visited = visited.IncrementUsage())
#pragma warning restore IDISP003 // Dispose previous before re-assigning.
{
if (visited.Add(target))
{
using (var walker = ReturnValueWalker.Borrow(target))
{
foreach (var returnValue in walker.ReturnValues)
{
if (!IsValueValidForRegisteredType(returnValue, registeredType, semanticModel, cancellationToken, visited))
{
return(false);
}
}
}
}
return(true);
}
}
return(method.ReturnType == KnownSymbols.Object);
}
}
