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-rw-r--r--utils/difftree/difftree.go194
1 files changed, 0 insertions, 194 deletions
diff --git a/utils/difftree/difftree.go b/utils/difftree/difftree.go
deleted file mode 100644
index e2cb9a5..0000000
--- a/utils/difftree/difftree.go
+++ /dev/null
@@ -1,194 +0,0 @@
-package difftree
-
-import (
- "bytes"
- "fmt"
- "io"
- "sort"
- "strings"
-
- "gopkg.in/src-d/go-git.v4"
- "gopkg.in/src-d/go-git.v4/core"
-)
-
-type Action int
-
-func (a Action) String() string {
- switch a {
- case Insert:
- return "Insert"
- case Delete:
- return "Delete"
- case Modify:
- return "Modify"
- default:
- panic(fmt.Sprintf("unsupported action: %d", a))
- }
-}
-
-const (
- Insert Action = iota
- Delete
- Modify
-)
-
-type Change struct {
- Action
- File *git.File
-}
-
-func (c *Change) String() string {
- return fmt.Sprintf("<Action: %s, Path: %s, Size: %d>", c.Action, c.File.Name, c.File.Size)
-}
-
-type Changes []*Change
-
-func newEmpty() Changes {
- return make([]*Change, 0, 0)
-}
-
-func New(a, b *git.Tree) (Changes, error) {
- if a == b {
- return newEmpty(), nil
- }
-
- if a == nil || b == nil {
- return newWithEmpty(a, b)
- }
-
- return newDiffTree(a, b)
-}
-
-func (c Changes) Len() int {
- return len(c)
-}
-
-func (c Changes) Swap(i, j int) {
- c[i], c[j] = c[j], c[i]
-}
-
-func (c Changes) Less(i, j int) bool {
- return strings.Compare(c[i].File.Name, c[j].File.Name) < 0
-}
-
-func (c Changes) String() string {
- var buffer bytes.Buffer
- buffer.WriteString("[")
- comma := ""
- for _, v := range c {
- buffer.WriteString(comma)
- buffer.WriteString(v.String())
- comma = ", "
- }
- buffer.WriteString("]")
-
- return buffer.String()
-}
-
-func newWithEmpty(a, b *git.Tree) (Changes, error) {
- changes := newEmpty()
-
- var action Action
- var tree *git.Tree
- if a == nil {
- action = Insert
- tree = b
- } else {
- action = Delete
- tree = a
- }
-
- iter := tree.Files()
- defer iter.Close()
-
- for {
- file, err := iter.Next()
- if err == io.EOF {
- break
- } else if err != nil {
- return nil, fmt.Errorf("cannot get next file: %s", err)
- }
-
- insert := &Change{
- Action: action,
- File: file,
- }
- changes = append(changes, insert)
- }
-
- return changes, nil
-}
-
-// FIXME: this is very inefficient, but correct.
-// The proper way to do this is to implement a diff-tree algorithm,
-// while taking advantage of the tree hashes to avoid traversing
-// subtrees when the hash is equal in both inputs.
-func newDiffTree(a, b *git.Tree) (Changes, error) {
- result := newEmpty()
-
- aChanges, err := newWithEmpty(a, nil)
- if err != nil {
- return nil, fmt.Errorf("cannot create nil-diff of source tree: %s", err)
- }
- sort.Sort(aChanges)
-
- bChanges, err := newWithEmpty(nil, b)
- if err != nil {
- return nil, fmt.Errorf("cannot create nil-diff of destination tree: %s", err)
- }
- sort.Sort(bChanges)
-
- for len(aChanges) > 0 && len(bChanges) > 0 {
- switch comp := strings.Compare(aChanges[0].File.Name, bChanges[0].File.Name); {
- case comp == 0: // append as "Modify" or ignore if not changed
- modified, err := hasChange(a, b, aChanges[0].File.Name)
- if err != nil {
- return nil, err
- }
- if modified {
- bChanges[0].Action = Modify
- result = append(result, bChanges[0])
- } else {
- }
- aChanges = aChanges[1:]
- bChanges = bChanges[1:]
- case comp < 0: // delete first a change
- result = append(result, aChanges[0])
- aChanges = aChanges[1:]
- case comp > 0: // insert first b change
- result = append(result, bChanges[0])
- bChanges = bChanges[1:]
- }
- }
-
- // append all remaining changes in aChanges, if any, as deletes
- // append all remaining changes in bChanges, if any, as inserts
- result = append(result, aChanges...)
- result = append(result, bChanges...)
-
- return result, nil
-}
-
-func hasChange(a, b *git.Tree, path string) (bool, error) {
- ha, err := hash(a, path)
- if err != nil {
- return false, err
- }
-
- hb, err := hash(b, path)
- if err != nil {
- return false, err
- }
-
- return ha != hb, nil
-}
-
-func hash(tree *git.Tree, path string) (core.Hash, error) {
- file, err := tree.File(path)
- if err != nil {
- var empty core.Hash
- return empty, fmt.Errorf("cannot find file %s in tree: %s", path, err)
- }
-
- return file.Hash, nil
-}