fixed: #516

src/DryIoc/Container.cs

@@ -9892,7 +9892,7 @@ public Request WithResolvedFactory(Factory factory,
                             scopedOrSingleton && p.Reuse is SingletonReuse ||
                             p.FactoryType == FactoryType.Wrapper && p._actualServiceType.IsFunc())
                             checkCaptiveDependency = false; // stop the check
-                        else if (p.FactoryType == FactoryType.Service && p.ReuseLifespan > reuseLifespan)
+                        else if (p.FactoryType != FactoryType.Wrapper && p.ReuseLifespan > reuseLifespan)
                             Throw.It(Error.DependencyHasShorterReuseLifespan, PrintCurrent(), reuse, p);
                     }
 

test/DryIoc.IssuesTests/GHIssue516_Singleton_Decorator_to_Scoped_base_should_not_work_but_does.cs

@@ -0,0 +1,41 @@
+using NUnit.Framework;
+
+namespace DryIoc.IssuesTests
+{
+    [TestFixture]
+    public class GHIssue516_Singleton_Decorator_to_Scoped_base_should_not_work_but_does : ITest
+    {
+        public int Run()
+        {
+            Example();
+            return 1;
+        }
+
+        [Test]
+        public void Example()
+        {
+            var c = new Container();
+            c.RegisterMany<A>(Reuse.Scoped);
+            c.Register<IFace, ADecorator>(Reuse.Singleton, setup: Setup.Decorator);
+
+            using (var s1 = c.OpenScope())
+            {
+                var ex = Assert.Throws<ContainerException>(() => s1.Resolve<IFace>());
+                Assert.AreEqual(Error.NameOf(Error.DependencyHasShorterReuseLifespan), ex.ErrorName);
+            }
+        }
+
+        public interface IFace { }
+
+        public class A : IFace { }
+
+        public class ADecorator : IFace
+        {
+            public IFace Inner { get; }
+            public ADecorator(IFace inner)
+            {
+                Inner = inner;
+            }
+        }
+    }
+}