From 0045f1bcd4f338fa575e5a6f437c7196c5fa3a9c Mon Sep 17 00:00:00 2001
From: Evgenii Stratonikov <e.stratonikov@yadro.com>
Date: Wed, 26 Apr 2023 17:07:51 +0300
Subject: [PATCH] [#288] pilorama: Use more descriptive names for memory tree

Signed-off-by: Evgenii Stratonikov <e.stratonikov@yadro.com>
---
 pkg/local_object_storage/pilorama/forest.go   | 12 +++----
 pkg/local_object_storage/pilorama/inmemory.go | 35 +++++++++----------
 2 files changed, 22 insertions(+), 25 deletions(-)

diff --git a/pkg/local_object_storage/pilorama/forest.go b/pkg/local_object_storage/pilorama/forest.go
index 0db91935..1110927f 100644
--- a/pkg/local_object_storage/pilorama/forest.go
+++ b/pkg/local_object_storage/pilorama/forest.go
@@ -12,7 +12,7 @@ import (
 // memoryForest represents multiple replicating trees sharing a single storage.
 type memoryForest struct {
 	// treeMap maps tree identifier (container ID + name) to the replicated log.
-	treeMap map[string]*state
+	treeMap map[string]*memoryTree
 }
 
 var _ Forest = (*memoryForest)(nil)
@@ -21,7 +21,7 @@ var _ Forest = (*memoryForest)(nil)
 // TODO: this function will eventually be removed and is here for debugging.
 func NewMemoryForest() ForestStorage {
 	return &memoryForest{
-		treeMap: make(map[string]*state),
+		treeMap: make(map[string]*memoryTree),
 	}
 }
 
@@ -34,7 +34,7 @@ func (f *memoryForest) TreeMove(_ context.Context, d CIDDescriptor, treeID strin
 	fullID := d.CID.String() + "/" + treeID
 	s, ok := f.treeMap[fullID]
 	if !ok {
-		s = newState()
+		s = newMemoryTree()
 		f.treeMap[fullID] = s
 	}
 
@@ -60,7 +60,7 @@ func (f *memoryForest) TreeAddByPath(_ context.Context, d CIDDescriptor, treeID
 	fullID := d.CID.String() + "/" + treeID
 	s, ok := f.treeMap[fullID]
 	if !ok {
-		s = newState()
+		s = newMemoryTree()
 		f.treeMap[fullID] = s
 	}
 
@@ -98,7 +98,7 @@ func (f *memoryForest) TreeApply(_ context.Context, cnr cid.ID, treeID string, o
 	fullID := cnr.String() + "/" + treeID
 	s, ok := f.treeMap[fullID]
 	if !ok {
-		s = newState()
+		s = newMemoryTree()
 		f.treeMap[fullID] = s
 	}
 
@@ -131,7 +131,7 @@ func (f *memoryForest) TreeGetByPath(_ context.Context, cid cid.ID, treeID strin
 		return nil, ErrTreeNotFound
 	}
 
-	return s.get(attr, path, latest), nil
+	return s.getByPath(attr, path, latest), nil
 }
 
 // TreeGetMeta implements the Forest interface.
diff --git a/pkg/local_object_storage/pilorama/inmemory.go b/pkg/local_object_storage/pilorama/inmemory.go
index bfc2a5b2..b836d4fb 100644
--- a/pkg/local_object_storage/pilorama/inmemory.go
+++ b/pkg/local_object_storage/pilorama/inmemory.go
@@ -14,21 +14,23 @@ type move struct {
 	Old    nodeInfo
 }
 
-// state represents state being replicated.
-type state struct {
+// memoryTree represents memoryTree being replicated.
+type memoryTree struct {
 	operations []move
 	tree
 }
 
-// newState constructs new empty tree.
-func newState() *state {
-	return &state{
-		tree: *newTree(),
+// newMemoryTree constructs new empty tree.
+func newMemoryTree() *memoryTree {
+	return &memoryTree{
+		tree: tree{
+			infoMap: make(map[Node]nodeInfo),
+		},
 	}
 }
 
 // undo un-does op and changes s in-place.
-func (s *state) undo(op *move) {
+func (s *memoryTree) undo(op *move) {
 	if op.HasOld {
 		s.tree.infoMap[op.Child] = op.Old
 	} else {
@@ -38,7 +40,7 @@ func (s *state) undo(op *move) {
 
 // Apply puts op in log at a proper position, re-applies all subsequent operations
 // from log and changes s in-place.
-func (s *state) Apply(op *Move) error {
+func (s *memoryTree) Apply(op *Move) error {
 	var index int
 	for index = len(s.operations); index > 0; index-- {
 		if s.operations[index-1].Time <= op.Time {
@@ -65,7 +67,7 @@ func (s *state) Apply(op *Move) error {
 }
 
 // do performs a single move operation on a tree.
-func (s *state) do(op *Move) move {
+func (s *memoryTree) do(op *Move) move {
 	lm := move{
 		Move: Move{
 			Parent: op.Parent,
@@ -96,14 +98,14 @@ func (s *state) do(op *Move) move {
 	return lm
 }
 
-func (s *state) timestamp(pos, size int) Timestamp {
+func (s *memoryTree) timestamp(pos, size int) Timestamp {
 	if len(s.operations) == 0 {
 		return nextTimestamp(0, uint64(pos), uint64(size))
 	}
 	return nextTimestamp(s.operations[len(s.operations)-1].Time, uint64(pos), uint64(size))
 }
 
-func (s *state) findSpareID() Node {
+func (s *memoryTree) findSpareID() Node {
 	id := uint64(1)
 	for _, ok := s.infoMap[id]; ok; _, ok = s.infoMap[id] {
 		id++
@@ -117,12 +119,6 @@ type tree struct {
 	infoMap    map[Node]nodeInfo
 }
 
-func newTree() *tree {
-	return &tree{
-		infoMap: make(map[Node]nodeInfo),
-	}
-}
-
 func (t tree) getChildren(parent Node) []Node {
 	var children []Node
 	for c, info := range t.infoMap {
@@ -175,9 +171,10 @@ loop:
 	return len(path), curNode
 }
 
-// get returns list of nodes which have the specified path from root
+// getByPath returns list of nodes which have the specified path from root
 // descending by values of attr from meta.
-func (t tree) get(attr string, path []string, latest bool) []Node {
+// If latest is true, only the latest node is returned.
+func (t tree) getByPath(attr string, path []string, latest bool) []Node {
 	if len(path) == 0 {
 		return nil
 	}