make pointer to value if needed (#200)

* make pointer to value if needed
* test
* narrow down change to structs passed in by value

changelog/v0.16.1/fix-equality.yaml

@@ -0,0 +1,5 @@
+changelog:
+  - type: FIX
+    description: >
+      Fix the case where proto.Message types are passed in by value rather than by pointer.
+    issueLink: https://github.com/solo-io/skv2/issues/199

contrib/codegen/templates/input/input_reconciler.gotmpl

@@ -56,7 +56,7 @@ type multiCluster{{ $snapshotName }}ReconcilerImpl struct {
     base input.InputReconciler
 }
 
-// Options for reconcileing a snapshot
+// Options for reconciling a snapshot
 type {{ $snapshotName }}ReconcileOptions struct {
 {{/* generate reconcile options here */}}
 {{- range $group := $groups }}

pkg/controllerutils/equality.go

@@ -49,8 +49,8 @@ func ObjectsEqual(obj1, obj2 runtime.Object) bool {
 			continue
 		}
 
-		field1 := value1.Field(i).Interface()
-		field2 := value2.Field(i).Interface()
+		field1 := mkPointer(value1.Field(i).Interface())
+		field2 := mkPointer(value2.Field(i).Interface())
 
 		// assert DeepEquality any other fields
 		if !equalityutils.DeepEqual(field1, field2) {
@@ -61,6 +61,26 @@ func ObjectsEqual(obj1, obj2 runtime.Object) bool {
 	return true
 }
 
+// if i is a pointer, just return the value.
+// if i is addressable, return that.
+// if i is a struct passed in by value, make a new instance of the type and copy the contents to that and return
+// the pointer to that.
+func mkPointer(i interface{}) interface{} {
+	val := reflect.ValueOf(i)
+	if val.Kind() == reflect.Ptr {
+		return i
+	}
+	if val.CanAddr() {
+		return val.Addr().Interface()
+	}
+	if val.Kind() == reflect.Struct {
+		nv := reflect.New(reflect.TypeOf(i))
+		nv.Elem().Set(val)
+		return nv.Interface()
+	}
+	return i
+}
+
 // returns true if "relevant" parts of obj1 and obj2 have equal:
 // -labels
 // -annotations

pkg/controllerutils/equality_test.go

@@ -81,6 +81,32 @@ var _ = Describe("ObjectsEqual", func() {
 		equal := ObjectsEqual(obj1, obj2)
 		Expect(equal).To(BeFalse())
 	})
+
+	It("asserts equality on two proto.Message objects even if they are passed in by value", func() {
+		obj1 := &things_test_io_v1.Paint{
+			Spec: things_test_io_v1.PaintSpec{
+				Color: &things_test_io_v1.PaintColor{
+					Hue: "red",
+				},
+				PaintType: &things_test_io_v1.PaintSpec_Oil{
+					Oil: nil,
+				},
+			},
+		}
+		obj1.Spec.ProtoReflect().SetUnknown([]byte(""))
+		obj2 := &things_test_io_v1.Paint{
+			Spec: things_test_io_v1.PaintSpec{
+				Color: &things_test_io_v1.PaintColor{
+					Hue: "red",
+				},
+				PaintType: &things_test_io_v1.PaintSpec_Oil{
+					Oil: nil,
+				},
+			},
+		}
+		equal := ObjectsEqual(obj1, obj2)
+		Expect(equal).To(BeTrue())
+	})
 })
 
 var _ = Describe("ObjectStatusesEqual", func() {