Handle ValuEtASK

fix #470

Author: JohanLarsson

IDisposableAnalyzers.Test/IDISP001DisposeCreatedTests/Valid.Returned.cs

@@ -404,6 +404,42 @@ public void Dispose()
             RoslynAssert.Valid(Analyzer, Disposable, code);
         }
 
+        [Test]
+        public static void ReturnInValueTask()
+        {
+            var disposable = """
+
+                namespace N;
+
+                using System;
+
+                public class Disposable : IDisposable
+                {
+                    public void Dispose()
+                    {
+                    }
+                }
+                """;
+
+            var code = """
+
+                namespace N;
+
+                using System;
+                using System.Threading.Tasks;
+
+                public class C
+                {
+                    public ValueTask<IDisposable> M()
+                    {
+                        var disposable = new Disposable();
+                        return new ValueTask<IDisposable>(disposable);
+                    }
+                }
+                """;
+            RoslynAssert.Valid(Analyzer, disposable, code);
+        }
+
         [Test]
         public static void LocalFunctionStatementBody()
         {

IDisposableAnalyzers/Helpers/Disposable.Identity.cs

@@ -31,6 +31,9 @@ parameter.ContainingSymbol is IMethodSymbol extensionMethod
                 { Parent: ArgumentSyntax { Parent: ArgumentListSyntax { Parent: InvocationExpressionSyntax { Expression: MemberAccessExpressionSyntax { Name: IdentifierNameSyntax { Identifier.ValueText: "FromResult" } } } invocation } } }
                     when invocation.IsSymbol(KnownSymbols.Task.FromResult, recursion.SemanticModel, recursion.CancellationToken)
                     => Recursive(invocation, recursion),
+                { Parent: ArgumentSyntax { Parent: ArgumentListSyntax { Parent: ObjectCreationExpressionSyntax { } objectCreation } } }
+                    when objectCreation.IsType(KnownSymbols.ValueTaskOfT, recursion.SemanticModel, recursion.CancellationToken)
+                    => Recursive(objectCreation, recursion),
                 { Parent: ArgumentSyntax { Parent: ArgumentListSyntax { Parent: InvocationExpressionSyntax invocation } } argument }
                     when recursion.Target(argument) is { } target &&
                          IsIdentity(target, recursion)