entc/gen: add eager-load edges to query clone (#888)

Closed #878

examples/m2m2types/ent/group_query.go

@@ -248,6 +248,9 @@ func (gq *GroupQuery) ExistX(ctx context.Context) bool {
 // Clone returns a duplicate of the query builder, including all associated steps. It can be
 // used to prepare common query builders and use them differently after the clone is made.
 func (gq *GroupQuery) Clone() *GroupQuery {
+	if gq == nil {
+		return nil
+	}
 	return &GroupQuery{
 		config:     gq.config,
 		limit:      gq.limit,
@@ -255,6 +258,7 @@ func (gq *GroupQuery) Clone() *GroupQuery {
 		order:      append([]OrderFunc{}, gq.order...),
 		unique:     append([]string{}, gq.unique...),
 		predicates: append([]predicate.Group{}, gq.predicates...),
+		withUsers:  gq.withUsers.Clone(),
 		// clone intermediate query.
 		sql:  gq.sql.Clone(),
 		path: gq.path,

examples/m2m2types/ent/user_query.go

@@ -248,6 +248,9 @@ func (uq *UserQuery) ExistX(ctx context.Context) bool {
 // Clone returns a duplicate of the query builder, including all associated steps. It can be
 // used to prepare common query builders and use them differently after the clone is made.
 func (uq *UserQuery) Clone() *UserQuery {
+	if uq == nil {
+		return nil
+	}
 	return &UserQuery{
 		config:     uq.config,
 		limit:      uq.limit,
@@ -255,6 +258,7 @@ func (uq *UserQuery) Clone() *UserQuery {
 		order:      append([]OrderFunc{}, uq.order...),
 		unique:     append([]string{}, uq.unique...),
 		predicates: append([]predicate.User{}, uq.predicates...),
+		withGroups: uq.withGroups.Clone(),
 		// clone intermediate query.
 		sql:  uq.sql.Clone(),
 		path: uq.path,