From 0d926c3c75d9f0850cd1d499de2aa214fd494689 Mon Sep 17 00:00:00 2001
From: Wenxuan Zhang <wenxuangm@gmail.com>
Date: Mon, 15 Nov 2021 14:55:45 +0800
Subject: [PATCH] feat: implement `Copy` for `XXXList`

---
 .../database/metadatav2/informer/group.go     |  2 +-
 .../database/metadatav2/informer/informer.go  | 40 ++-----------------
 pkg/oomstore/typesv2/entity.go                | 11 +++++
 pkg/oomstore/typesv2/feature.go               | 11 +++++
 pkg/oomstore/typesv2/feature_group.go         | 11 +++++
 pkg/oomstore/typesv2/revision.go              | 11 +++++
 6 files changed, 49 insertions(+), 37 deletions(-)

diff --git a/internal/database/metadatav2/informer/group.go b/internal/database/metadatav2/informer/group.go
index 8fd0f9f77..952811064 100644
--- a/internal/database/metadatav2/informer/group.go
+++ b/internal/database/metadatav2/informer/group.go
@@ -16,7 +16,7 @@ func (c *GroupCache) Enrich(entityCache *EntityCache) {
 	}
 }
 
-func (c *GroupCache) List(entityID *int16) []*typesv2.FeatureGroup {
+func (c *GroupCache) List(entityID *int16) typesv2.FeatureGroupList {
 	if entityID == nil {
 		return c.FeatureGroupList
 	}
diff --git a/internal/database/metadatav2/informer/informer.go b/internal/database/metadatav2/informer/informer.go
index 724ff2e61..754553acf 100644
--- a/internal/database/metadatav2/informer/informer.go
+++ b/internal/database/metadatav2/informer/informer.go
@@ -175,49 +175,17 @@ func (f *Informer) GetRevisionBy(ctx context.Context, groupID int16, revision in
 
 // List
 func (f *Informer) ListEntity(ctx context.Context) typesv2.EntityList {
-	list := f.Cache().Entities.List()
-	if len(list) == 0 {
-		return nil
-	}
-	copied := make(typesv2.EntityList, 0, len(list))
-	for _, x := range list {
-		copied = append(copied, x.Copy())
-	}
-	return copied
+	return f.Cache().Entities.List().Copy()
 }
 
 func (f *Informer) ListFeature(ctx context.Context, opt metadatav2.ListFeatureOpt) typesv2.FeatureList {
-	list := f.Cache().Features.List(opt)
-	if len(list) == 0 {
-		return nil
-	}
-	copied := make(typesv2.FeatureList, 0, len(list))
-	for _, x := range list {
-		copied = append(copied, x.Copy())
-	}
-	return copied
+	return f.Cache().Features.List(opt).Copy()
 }
 
 func (f *Informer) ListFeatureGroup(ctx context.Context, entityID *int16) typesv2.FeatureGroupList {
-	list := f.Cache().Groups.List(entityID)
-	if len(list) == 0 {
-		return nil
-	}
-	copied := make(typesv2.FeatureGroupList, 0, len(list))
-	for _, x := range list {
-		copied = append(copied, x.Copy())
-	}
-	return copied
+	return f.Cache().Groups.List(entityID).Copy()
 }
 
 func (f *Informer) ListRevision(ctx context.Context, opt metadatav2.ListRevisionOpt) typesv2.RevisionList {
-	list := f.Cache().Revisions.List(opt)
-	if len(list) == 0 {
-		return nil
-	}
-	copied := make(typesv2.RevisionList, 0, len(list))
-	for _, x := range list {
-		copied = append(copied, x.Copy())
-	}
-	return copied
+	return f.Cache().Revisions.List(opt).Copy()
 }
diff --git a/pkg/oomstore/typesv2/entity.go b/pkg/oomstore/typesv2/entity.go
index 848cb0fbf..6ffe8661e 100644
--- a/pkg/oomstore/typesv2/entity.go
+++ b/pkg/oomstore/typesv2/entity.go
@@ -26,6 +26,17 @@ func (e *Entity) Copy() *Entity {
 
 type EntityList []*Entity
 
+func (l EntityList) Copy() EntityList {
+	if len(l) == 0 {
+		return nil
+	}
+	copied := make(EntityList, 0, len(l))
+	for _, x := range l {
+		copied = append(copied, x.Copy())
+	}
+	return copied
+}
+
 func (l *EntityList) Find(find func(*Entity) bool) *Entity {
 	for _, e := range *l {
 		if find(e) {
diff --git a/pkg/oomstore/typesv2/feature.go b/pkg/oomstore/typesv2/feature.go
index 3768d6f87..49b6732bb 100644
--- a/pkg/oomstore/typesv2/feature.go
+++ b/pkg/oomstore/typesv2/feature.go
@@ -42,6 +42,17 @@ func (f *Feature) OnlineRevisionID() *int32 {
 
 type FeatureList []*Feature
 
+func (l FeatureList) Copy() FeatureList {
+	if len(l) == 0 {
+		return nil
+	}
+	copied := make(FeatureList, 0, len(l))
+	for _, x := range l {
+		copied = append(copied, x.Copy())
+	}
+	return copied
+}
+
 func (l *FeatureList) Len() int { return len(*l) }
 
 func (l *FeatureList) Names() (names []string) {
diff --git a/pkg/oomstore/typesv2/feature_group.go b/pkg/oomstore/typesv2/feature_group.go
index 24e64974e..9b420eafa 100644
--- a/pkg/oomstore/typesv2/feature_group.go
+++ b/pkg/oomstore/typesv2/feature_group.go
@@ -38,6 +38,17 @@ func (fg *FeatureGroup) Copy() *FeatureGroup {
 
 type FeatureGroupList []*FeatureGroup
 
+func (l FeatureGroupList) Copy() FeatureGroupList {
+	if len(l) == 0 {
+		return nil
+	}
+	copied := make(FeatureGroupList, 0, len(l))
+	for _, x := range l {
+		copied = append(copied, x.Copy())
+	}
+	return copied
+}
+
 func (l *FeatureGroupList) Find(find func(*FeatureGroup) bool) *FeatureGroup {
 	for _, g := range *l {
 		if find(g) {
diff --git a/pkg/oomstore/typesv2/revision.go b/pkg/oomstore/typesv2/revision.go
index 6d8a17c8e..6e9ed3810 100644
--- a/pkg/oomstore/typesv2/revision.go
+++ b/pkg/oomstore/typesv2/revision.go
@@ -32,6 +32,17 @@ func (r *Revision) Copy() *Revision {
 
 type RevisionList []*Revision
 
+func (l RevisionList) Copy() RevisionList {
+	if len(l) == 0 {
+		return nil
+	}
+	copied := make(RevisionList, 0, len(l))
+	for _, x := range l {
+		copied = append(copied, x.Copy())
+	}
+	return copied
+}
+
 func (l *RevisionList) Find(find func(*Revision) bool) *Revision {
 	for _, r := range *l {
 		if find(r) {