Avoid Attribute.GetCustomAttributes() returning null for open generic type

* Revert "Revert "Avoid Attribute.GetCustomAttributes() returning null for open generic type (#65237)" (#66508)"

This reverts commit f99ba2e2b8fbf03be5058ad23e8cdce9c4a09da6.

* Make DynamicMethod.GetCustomAttributes() return well-typed arrays.

This change makes DynamicMethod.GetCustomAttributes() compatible with
Attribute.GetCustomAttributes().

2 files changed, 14 insertions, 3 deletions

diff --git a/src/tests/reflection/GenericAttribute/GenericAttributeMetadata.cs b/src/tests/reflection/GenericAttribute/GenericAttributeMetadata.cs
index d0ef6353f4a..3bea1e62194 100644
--- a/src/tests/reflection/GenericAttribute/GenericAttributeMetadata.cs
+++ b/src/tests/reflection/GenericAttribute/GenericAttributeMetadata.cs
@@ -17,6 +17,8 @@ using System.Runtime.CompilerServices;
 [assembly: MultiAttribute<bool>()]
 [assembly: MultiAttribute<bool>(true)]
 
+[module: SingleAttribute<long>()]
+
 [AttributeUsage(AttributeTargets.Assembly | AttributeTargets.Class | AttributeTargets.Property, AllowMultiple = false)]
 public class SingleAttribute<T> : Attribute
 {
diff --git a/src/tests/reflection/GenericAttribute/GenericAttributeTests.cs b/src/tests/reflection/GenericAttribute/GenericAttributeTests.cs
index e7661d2d5ae..3462830f1ed 100644
--- a/src/tests/reflection/GenericAttribute/GenericAttributeTests.cs
+++ b/src/tests/reflection/GenericAttribute/GenericAttributeTests.cs
@@ -18,9 +18,18 @@ class Program
         Assert(((ICustomAttributeProvider)assembly).IsDefined(typeof(SingleAttribute<int>), true));
         Assert(CustomAttributeExtensions.IsDefined(assembly, typeof(SingleAttribute<bool>)));
         Assert(((ICustomAttributeProvider)assembly).IsDefined(typeof(SingleAttribute<bool>), true));
-
+        Assert(!CustomAttributeExtensions.GetCustomAttributes(assembly, typeof(SingleAttribute<>)).GetEnumerator().MoveNext());
+        Assert(!CustomAttributeExtensions.GetCustomAttributes(assembly, typeof(SingleAttribute<>)).GetEnumerator().MoveNext());
 */
 
+        // Uncomment when https://github.com/dotnet/runtime/issues/66168 is resolved
+        // Module module = programTypeInfo.Module;
+        // AssertAny(CustomAttributeExtensions.GetCustomAttributes(module), a => a is SingleAttribute<long>);
+        // Assert(CustomAttributeExtensions.GetCustomAttributes(module, typeof(SingleAttribute<long>)).GetEnumerator().MoveNext());
+        // Assert(CustomAttributeExtensions.GetCustomAttributes(module, typeof(SingleAttribute<long>)).GetEnumerator().MoveNext());
+        // Assert(!CustomAttributeExtensions.GetCustomAttributes(module, typeof(SingleAttribute<>)).GetEnumerator().MoveNext());
+        // Assert(!CustomAttributeExtensions.GetCustomAttributes(module, typeof(SingleAttribute<>)).GetEnumerator().MoveNext());	
+
         TypeInfo programTypeInfo = typeof(Class).GetTypeInfo();
         Assert(CustomAttributeExtensions.GetCustomAttribute<SingleAttribute<int>>(programTypeInfo) != null);
         Assert(((ICustomAttributeProvider)programTypeInfo).GetCustomAttributes(typeof(SingleAttribute<int>), true) != null);
@@ -152,8 +161,8 @@ class Program
         AssertAny(b10, a => (a as MultiAttribute<Type>)?.Value == typeof(Class));
         AssertAny(b10, a => (a as MultiAttribute<Type>)?.Value == typeof(Class.Derive));
 
-        Assert(CustomAttributeExtensions.GetCustomAttributes(programTypeInfo, typeof(MultiAttribute<>), false) == null);
-        Assert(CustomAttributeExtensions.GetCustomAttributes(programTypeInfo, typeof(MultiAttribute<>), true) == null);
+        Assert(!CustomAttributeExtensions.GetCustomAttributes(programTypeInfo, typeof(MultiAttribute<>), false).GetEnumerator().MoveNext());
+        Assert(!CustomAttributeExtensions.GetCustomAttributes(programTypeInfo, typeof(MultiAttribute<>), true).GetEnumerator().MoveNext());
         Assert(!((ICustomAttributeProvider)programTypeInfo).GetCustomAttributes(typeof(MultiAttribute<>), true).GetEnumerator().MoveNext());
 
         // Test coverage for CustomAttributeData api surface