un-expose hooks copy

core/tracing/hooks.go

@@ -207,8 +207,10 @@ type Hooks struct {
 	OnBlockHashRead BlockHashReadHook
 }
 
-// Copy creates a new Hooks instance with all implemented hooks copied from the original.
+// copy creates a new Hooks instance with all implemented hooks copied from the original.
-func (h *Hooks) Copy() *Hooks {
+// Note: it is not a deep copy. If a hook has been implemented as a closure and acts on
+// a mutable state, the copied hook will still act on the same state.
+func (h *Hooks) copy() *Hooks {
 	copied := &Hooks{}
 	srcValue := reflect.ValueOf(h).Elem()
 	dstValue := reflect.ValueOf(copied).Elem()

core/tracing/journal.go

@@ -62,7 +62,7 @@ func WrapWithJournal(hooks *Hooks) (*Hooks, error) {
 	}
 
 	// Create a new Hooks instance and copy all hooks
-	wrapped := hooks.Copy()
+	wrapped := hooks.copy()
 	// Create journal
 	j := &journal{entries: make([]entry, 0), hooks: hooks}
 	// Scope hooks need to be re-implemented.

core/tracing/journal_test.go

@@ -179,7 +179,7 @@ func TestAllHooksCalled(t *testing.T) {
 			continue
 		}
 		// Skip non-hooks, i.e. Copy
-		if field.Name == "Copy" {
+		if field.Name == "copy" {
 			continue
 		}