plumbing/object: move difftree to object package

- To avoid ciclic dependency errors, we move all the difftree files to object package.
- Added Diff method to Tree object.

1 files changed, 0 insertions, 141 deletions

diff --git a/plumbing/difftree/treenoder.go b/plumbing/difftree/treenoder.go
deleted file mode 100644
index c0ed948..0000000
--- a/plumbing/difftree/treenoder.go
+++ /dev/null
@@ -1,141 +0,0 @@
-package difftree
-
-// 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 (
-	"encoding/binary"
-	"io"
-	"os"
-
-	"srcd.works/go-git.v4/plumbing"
-	"srcd.works/go-git.v4/plumbing/object"
-	"srcd.works/go-git.v4/utils/merkletrie/noder"
-)
-
-type treeNoder struct {
-	parent   *object.Tree // the root node is its own parent
-	name     string       // empty string for the root node
-	mode     os.FileMode
-	hash     plumbing.Hash
-	children []noder.Noder // memoized
-}
-
-func newTreeNoder(t *object.Tree) *treeNoder {
-	if t == nil {
-		return &treeNoder{}
-	}
-
-	return &treeNoder{
-		parent: t,
-		name:   "",
-		mode:   os.ModeDir,
-		hash:   t.Hash,
-	}
-}
-
-func (t *treeNoder) isRoot() bool {
-	return t.name == ""
-}
-
-func (t *treeNoder) String() string {
-	return "treeNoder <" + t.name + ">"
-}
-
-func (t *treeNoder) Hash() []byte {
-	return append(t.hash[:], modeToBytes(t.mode)...)
-}
-
-// mode in little endian (endianess is an arbitrary decission).
-func modeToBytes(m os.FileMode) []byte {
-	ret := make([]byte, 4)
-	binary.LittleEndian.PutUint32(ret, uint32(m))
-	return ret
-}
-
-func (t *treeNoder) Name() string {
-	return t.name
-}
-
-func (t *treeNoder) IsDir() bool {
-	return t.mode.IsDir()
-}
-
-// Children will return the children of a treenoder as treenoders,
-// building them from the children of the wrapped git tree.
-func (t *treeNoder) Children() ([]noder.Noder, error) {
-	if !t.mode.IsDir() {
-		return noder.NoChildren, nil
-	}
-
-	// children are memoized for efficiency
-	if t.children != nil {
-		return t.children, nil
-	}
-
-	// the parent of the returned children will be ourself as a tree if
-	// we are a not the root treenoder.  The root is special as it
-	// is is own parent.
-	parent := t.parent
-	if !t.isRoot() {
-		var err error
-		if parent, err = t.parent.Tree(t.name); err != nil {
-			return nil, err
-		}
-	}
-
-	return transformChildren(parent)
-}
-
-// Returns the children of a tree as treenoders.
-// Efficiency is key here.
-func transformChildren(t *object.Tree) ([]noder.Noder, error) {
-	var err error
-	var e object.TreeEntry
-
-	// there will be more tree entries than children in the tree,
-	// due to submodules and empty directories, but I think it is still
-	// worth it to pre-allocate the whole array now, even if sometimes
-	// is bigger than needed.
-	ret := make([]noder.Noder, 0, len(t.Entries))
-
-	walker := object.NewTreeWalker(t, false) // don't recurse
-	// don't defer walker.Close() for efficiency reasons.
-	for {
-		_, e, err = walker.Next()
-		if err == io.EOF {
-			break
-		}
-		if err != nil {
-			walker.Close()
-			return nil, err
-		}
-
-		ret = append(ret, &treeNoder{
-			parent: t,
-			name:   e.Name,
-			mode:   e.Mode,
-			hash:   e.Hash,
-		})
-	}
-	walker.Close()
-
-	return ret, nil
-}
-
-// len(t.tree.Entries) != the number of elements walked by treewalker
-// for some reason because of empty directories, submodules, etc, so we
-// have to walk here.
-func (t *treeNoder) NumChildren() (int, error) {
-	children, err := t.Children()
-	if err != nil {
-		return 0, err
-	}
-
-	return len(children), nil
-}