merkletrie: filesystem and index speedup and documentation

1 files changed, 11 insertions, 18 deletions

diff --git a/plumbing/object/treenoder.go b/plumbing/object/treenoder.go
index 8b56d1b..bd65abc 100644
--- a/plumbing/object/treenoder.go
+++ b/plumbing/object/treenoder.go
@@ -1,13 +1,5 @@
 package object
 
-// A treenoder is a helper type that wraps git trees into merkletrie
-// noders.
-//
-// As a merkletrie noder doesn't understand the concept of modes (e.g.
-// file permissions), the treenoder includes the mode of the git tree in
-// the hash, so changes in the modes will be detected as modifications
-// to the file contents by the merkletrie difftree algorithm.  This is
-// consistent with how the "git diff-tree" command works.
 import (
 	"io"
 
@@ -16,16 +8,24 @@ import (
 	"gopkg.in/src-d/go-git.v4/utils/merkletrie/noder"
 )
 
+// A treenoder is a helper type that wraps git trees into merkletrie
+// noders.
+//
+// As a merkletrie noder doesn't understand the concept of modes (e.g.
+// file permissions), the treenoder includes the mode of the git tree in
+// the hash, so changes in the modes will be detected as modifications
+// to the file contents by the merkletrie difftree algorithm.  This is
+// consistent with how the "git diff-tree" command works.
 type treeNoder struct {
 	parent   *Tree  // the root node is its own parent
 	name     string // empty string for the root node
 	mode     filemode.FileMode
 	hash     plumbing.Hash
-	children []noder.Noder // memorized
+	children []noder.Noder // memoized
 }
 
 // NewTreeRootNode returns the root node of a Tree
-func NewTreeRootNode(t *Tree) *treeNoder {
+func NewTreeRootNode(t *Tree) noder.Noder {
 	if t == nil {
 		return &treeNoder{}
 	}
@@ -46,13 +46,6 @@ func (t *treeNoder) String() string {
 	return "treeNoder <" + t.name + ">"
 }
 
-// The hash of a treeNoder is the result of concatenating the hash of
-// its contents and its mode; that way the difftree algorithm will
-// detect changes in the contents of files and also in their mode.
-//
-// Files with Regular and Deprecated file modes are considered the same
-// for the purpose of difftree, so Regular will be used as the mode for
-// Deprecated files here.
 func (t *treeNoder) Hash() []byte {
 	if t.mode == filemode.Deprecated {
 		return append(t.hash[:], filemode.Regular.Bytes()...)
@@ -75,7 +68,7 @@ func (t *treeNoder) Children() ([]noder.Noder, error) {
 		return noder.NoChildren, nil
 	}
 
-	// children are memorized for efficiency
+	// children are memoized for efficiency
 	if t.children != nil {
 		return t.children, nil
 	}