public static void ArgumentOverloaded()
{
var tree = CSharpSyntaxTree.ParseText(@"
namespace N
{
public class C1
{
public int P => M(1);
public virtual int M(int n) => n;
}
public class C2
{
public override int M(int x) => x;
}
}");
var compilation = CSharpCompilation.Create("test", new[] { tree });
var semanticModel = compilation.GetSemanticModel(tree);
Assert.AreEqual(true, semanticModel.TryGetNamedType(tree.FindClassDeclaration("C2"), CancellationToken.None, out var type));
using var recursion = Recursion.Borrow(type, semanticModel, CancellationToken.None);
var node = tree.FindArgument("1");
var target = recursion.Target(node).Value;
Assert.AreEqual(node, target.Source);
Assert.AreEqual("int x", target.Symbol.ToDisplayString(Format));
Assert.AreEqual("public override int M(int x) => x;", target.Declaration.ToString());
}
public static void LocalFunction()
{
var tree = CSharpSyntaxTree.ParseText(@"
namespace N
{
public static class C
{
public static int P
{
get
{
return M();
int M() => 1;
}
}
}
}");
var compilation = CSharpCompilation.Create("test", new[] { tree });
var semanticModel = compilation.GetSemanticModel(tree);
Assert.AreEqual(true, semanticModel.TryGetNamedType(tree.FindClassDeclaration("C"), CancellationToken.None, out var type));
using var recursion = Recursion.Borrow(type, semanticModel, CancellationToken.None);
var node = tree.FindInvocation("M()");
var target = recursion.Target(node).Value;
Assert.AreEqual("M()", target.Source.ToString());
Assert.AreEqual("M()", target.Symbol.ToDisplayString(Format));
Assert.AreEqual("int M() => 1;", target.Declaration.ToString());
}
public static void RecursionTargetExtensionMethodArgumentsStaticInvocation()
{
var tree = CSharpSyntaxTree.ParseText(@"
namespace N
{
public static class C
{
public static int P => M(1, 2);
public static int M(this int m, int n) => m + n;
}
}");
var compilation = CSharpCompilation.Create("test", new[] { tree });
var semanticModel = compilation.GetSemanticModel(tree);
Assert.AreEqual(true, semanticModel.TryGetNamedType(tree.FindClassDeclaration("C"), CancellationToken.None, out var type));
using var recursion = Recursion.Borrow(type, semanticModel, CancellationToken.None);
var argument = tree.FindArgument("1");
var target = recursion.Target(argument).Value;
using var walker1 = UsagesWalker.Borrow(target.Symbol, target.Declaration, semanticModel, CancellationToken.None);
Assert.AreEqual("m", string.Join(", ", walker1.Usages));
argument = tree.FindArgument("2");
target = recursion.Target(argument).Value;
using var walker2 = UsagesWalker.Borrow(target.Symbol, target.Declaration, semanticModel, CancellationToken.None);
Assert.AreEqual("n", string.Join(", ", walker2.Usages));
}
public static void RecursionTargetExtensionMethodArgumentsGeneric()
{
var tree = CSharpSyntaxTree.ParseText(@"
namespace N
{
public static class C
{
public static bool P => 1.M<int>(2);
public static bool M<T>(this T m, T n) => Equals(m, n);
}
}");
var compilation = CSharpCompilation.Create("test", new[] { tree });
var semanticModel = compilation.GetSemanticModel(tree);
Assert.AreEqual(true, semanticModel.TryGetNamedType(tree.FindClassDeclaration("C"), CancellationToken.None, out var type));
using var recursion = Recursion.Borrow(type, semanticModel, CancellationToken.None);
var invocation = tree.FindInvocation("1.M<int>(2");
var invocationTarget = recursion.Target(invocation).Value;
using var invocationWalker = UsagesWalker.Borrow(invocationTarget.Symbol, invocationTarget.Declaration, semanticModel, CancellationToken.None);
Assert.AreEqual("m", string.Join(", ", invocationWalker.Usages));
var argument = tree.FindArgument("2");
var argumentTarget = recursion.Target(argument).Value;
using var argumentWalker = UsagesWalker.Borrow(argumentTarget.Symbol, argumentTarget.Declaration, semanticModel, CancellationToken.None);
Assert.AreEqual("n", string.Join(", ", argumentWalker.Usages));
}
internal static bool IsValueValidForRegisteredType(ExpressionSyntax value, ITypeSymbol registeredType, SemanticModel semanticModel, CancellationToken cancellationToken)
{
if (value.FirstAncestor <TypeDeclarationSyntax>() is { } containingTypeDeclaration&&
semanticModel.TryGetNamedType(containingTypeDeclaration, cancellationToken, out var containingType))
{
using var recursion = Recursion.Borrow(containingType, semanticModel, cancellationToken);
return(IsValueValidForRegisteredType(value, registeredType, recursion));
}
return(true);
internal static bool Ignores(ExpressionSyntax candidate, SemanticModel semanticModel, CancellationToken cancellationToken)
{
if (candidate.TryFirstAncestor(out TypeDeclarationSyntax? containingTypeDeclaration) &&
semanticModel.TryGetNamedType(containingTypeDeclaration, cancellationToken, out var containingType))
{
using var recursion = Recursion.Borrow(containingType, semanticModel, cancellationToken);
return(Ignores(candidate, recursion));
}
return(false);
}
internal static bool TryGet(ExpressionSyntax expression, SemanticModel semanticModel, CancellationToken cancellationToken, [NotNullWhen(true)] out ITypeSymbol?result, [NotNullWhen(true)] out ExpressionSyntax?source)
{
if (expression.TryFirstAncestor(out TypeDeclarationSyntax? containingType) &&
semanticModel.TryGetNamedType(containingType, cancellationToken, out var type))
{
using var recursion = Recursion.Borrow(type, semanticModel, cancellationToken);
return(TryGet(expression, recursion, out result, out source));
}
result = null;
source = null;
return(false);
}
internal static bool Returns(LocalOrParameter localOrParameter, SemanticModel semanticModel, CancellationToken cancellationToken)
{
using var recursion = Recursion.Borrow(localOrParameter.Symbol.ContainingType, semanticModel, cancellationToken);
using var walker = UsagesWalker.Borrow(localOrParameter, recursion.SemanticModel, recursion.CancellationToken);
foreach (var usage in walker.Usages)
{
if (Returns(usage, recursion))
{
return(true);
}
}
return(false);
}
internal static bool Stores(LocalOrParameter localOrParameter, SemanticModel semanticModel, CancellationToken cancellationToken, [NotNullWhen(true)] out ISymbol?container)
{
using var recursion = Recursion.Borrow(localOrParameter.Symbol.ContainingType, semanticModel, cancellationToken);
using var walker = UsagesWalker.Borrow(localOrParameter, semanticModel, cancellationToken);
foreach (var usage in walker.Usages)
{
if (Stores(usage, recursion, out container))
{
return(true);
}
}
container = null;
return(false);
}
internal static bool DisposedByReturnValue(ArgumentSyntax candidate, SemanticModel semanticModel, CancellationToken cancellationToken, [NotNullWhen(true)] out ExpressionSyntax?creation)
{
if (candidate.TryFirstAncestor(out TypeDeclarationSyntax? containingTypeDeclaration) &&
semanticModel.TryGetNamedType(containingTypeDeclaration, cancellationToken, out var containingType))
{
using var recursion = Recursion.Borrow(containingType, semanticModel, cancellationToken);
if (recursion.Target(candidate) is { } target)
{
return(DisposedByReturnValue(target, recursion, out creation));
}
}
creation = null;
return(false);
}
private static bool Ignores(ExpressionSyntax candidate, Recursion recursion)
{
using (var temp = Recursion.Borrow(recursion.ContainingType, recursion.SemanticModel, recursion.CancellationToken))
{
if (Disposes(candidate, temp))
{
return(false);
}
}
using (var temp = Recursion.Borrow(recursion.ContainingType, recursion.SemanticModel, recursion.CancellationToken))
{
if (Assigns(candidate, temp, out _))
{
return(false);
}
}
using (var temp = Recursion.Borrow(recursion.ContainingType, recursion.SemanticModel, recursion.CancellationToken))
{
if (Stores(candidate, temp, out _))
{
return(false);
}
}
using (var temp = Recursion.Borrow(recursion.ContainingType, recursion.SemanticModel, recursion.CancellationToken))
{
if (Returns(candidate, temp))
{
return(false);
}
}
return(candidate switch
{
{ Parent : AssignmentExpressionSyntax {
Left : IdentifierNameSyntax {
Identifier : { ValueText : "_" }
}
} }
internal static bool ShouldDispose(LocalOrParameter localOrParameter, SemanticModel semanticModel, CancellationToken cancellationToken)
{
if (localOrParameter.Symbol is IParameterSymbol parameter &&
parameter.RefKind != RefKind.None)
{
return(false);
}
using var recursion = Recursion.Borrow(localOrParameter.Symbol.ContainingType, semanticModel, cancellationToken);
using var walker = UsagesWalker.Borrow(localOrParameter, semanticModel, cancellationToken);
foreach (var usage in walker.Usages)
{
if (Returns(usage, recursion))
{
return(false);
}
if (Assigns(usage, recursion, out _))
{
return(false);
}
if (Stores(usage, recursion, out _))
{
return(false);
}
if (Disposes(usage, recursion))
{
return(false);
}
if (DisposedByReturnValue(usage, recursion, out _))
{
return(false);
}
}
return(true);
}
public static void RecursionTargetArgumentGeneric()
{
var tree = CSharpSyntaxTree.ParseText(@"
namespace N
{
public class C
{
public int P => this.M<int>(1);
public T M<T>(T n) => n;
}
}");
var compilation = CSharpCompilation.Create("test", new[] { tree });
var semanticModel = compilation.GetSemanticModel(tree);
Assert.AreEqual(true, semanticModel.TryGetNamedType(tree.FindClassDeclaration("C"), CancellationToken.None, out var type));
using var recursion = Recursion.Borrow(type, semanticModel, CancellationToken.None);
var node = tree.FindArgument("1");
var target = recursion.Target(node).Value;
using var walker = UsagesWalker.Borrow(target.Symbol, target.Declaration, semanticModel, CancellationToken.None);
Assert.AreEqual("n", string.Join(", ", walker.Usages));
}
public static void ArgumentGeneric()
{
var tree = CSharpSyntaxTree.ParseText(@"
namespace N
{
public class C
{
public int P => this.M<int>(1);
public T M<T>(T n) => n;
}
}");
var compilation = CSharpCompilation.Create("test", new[] { tree });
var semanticModel = compilation.GetSemanticModel(tree);
Assert.AreEqual(true, semanticModel.TryGetNamedType(tree.FindClassDeclaration("C"), CancellationToken.None, out var type));
using var recursion = Recursion.Borrow(type, semanticModel, CancellationToken.None);
var node = tree.FindArgument("1");
var target = recursion.Target(node).Value;
Assert.AreEqual(node, target.Source);
Assert.AreEqual("T n", target.Symbol.ToDisplayString(Format));
Assert.AreEqual("public T M<T>(T n) => n;", target.Declaration.ToString());
}
public static void ExtensionMethodConditional()
{
var tree = CSharpSyntaxTree.ParseText(@"
namespace N
{
public static class C
{
public static int M1(int? i) => i?.M2() ?? 0;
public static int M2(this int n) => n;
}
}");
var compilation = CSharpCompilation.Create("test", new[] { tree });
var semanticModel = compilation.GetSemanticModel(tree);
Assert.AreEqual(true, semanticModel.TryGetNamedType(tree.FindClassDeclaration("C"), CancellationToken.None, out var type));
using var recursion = Recursion.Borrow(type, semanticModel, CancellationToken.None);
var node = tree.FindInvocation("i?.M2()");
var target = recursion.Target(node).Value;
Assert.AreEqual("i", target.Source.ToString());
Assert.AreEqual("int n", target.Symbol.ToDisplayString(Format));
Assert.AreEqual("public static int M2(this int n) => n;", target.Declaration.ToString());
}