diff --git a/internal/deepcopy.go b/internal/deepcopy.go
index d000bd947..690b68fbe 100644
--- a/internal/deepcopy.go
+++ b/internal/deepcopy.go
@@ -7,7 +7,7 @@ import (
 	v1 "github.com/opencontainers/image-spec/specs-go/v1"
 )
 
-// DeepCopyDescriptor copies a Descriptor, deeply copying its contents
+// DeepCopyDescriptor copies a Descriptor, deeply copying its contents.
 func DeepCopyDescriptor(original *v1.Descriptor) *v1.Descriptor {
 	tmp := *original
 	if original.URLs != nil {
diff --git a/pkg/manifests/manifests_test.go b/pkg/manifests/manifests_test.go
index 2f2adae4e..a9f7d3301 100644
--- a/pkg/manifests/manifests_test.go
+++ b/pkg/manifests/manifests_test.go
@@ -105,10 +105,10 @@ func TestAddInstance(t *testing.T) {
 			t.Fatalf("adding an instance without platform info failed in %s: %v", version, err)
 		}
 		o, err := list.findOCIv1(manifestDigest)
-		if o == nil || err != nil {
+		if err != nil {
 			t.Fatalf("adding an instance failed in %s: %v", version, err)
 		}
-		if o.Platform != nil {
+		if o != nil && o.Platform != nil {
 			t.Fatalf("added a Platform field (%+v) where none was expected: %v", o.Platform, err)
 		}
 	}