diff options
Diffstat (limited to 'difftrees.go')
| -rw-r--r-- | difftrees.go | 207 |
1 files changed, 0 insertions, 207 deletions
diff --git a/difftrees.go b/difftrees.go deleted file mode 100644 index ea21687c..00000000 --- a/difftrees.go +++ /dev/null @@ -1,207 +0,0 @@ -package furgit - -// TreeDiffEntryKind represents the type of difference between two tree entries. -type TreeDiffEntryKind int - -const ( - // TreeDiffEntryKindInvalid indicates an invalid difference type. - TreeDiffEntryKindInvalid TreeDiffEntryKind = iota - // TreeDiffEntryKindDeleted indicates that the entry was deleted. - TreeDiffEntryKindDeleted - // TreeDiffEntryKindAdded indicates that the entry was added. - TreeDiffEntryKindAdded - // TreeDiffEntryKindModified indicates that the entry was modified. - TreeDiffEntryKindModified -) - -// TreeDiffEntry represents a difference between two tree entries. -type TreeDiffEntry struct { - // Path is the full slash-separated path relative to the root - // of the repository. - Path []byte - // Kind indicates the type of difference. - Kind TreeDiffEntryKind - // Old is the old tree entry (nil iff added). - Old *TreeEntry - // New is the new tree entry (nil iff deleted). - New *TreeEntry -} - -// DiffTrees compares two trees rooted at a and b and returns all differences -// as a flat slice of TreeDiffEntry. Differences are discovered recursively. -func (repo *Repository) DiffTrees(a, b *StoredTree) ([]TreeDiffEntry, error) { - var out []TreeDiffEntry - err := repo.diffTreesRecursive(a, b, nil, &out) - return out, err -} - -func (repo *Repository) diffTreesRecursive(a, b *StoredTree, prefix []byte, out *[]TreeDiffEntry) error { - if a == nil && b == nil { - return nil - } - - if a == nil { - for i := range b.Entries { - entry := &b.Entries[i] - full := joinPath(prefix, entry.Name) - - *out = append(*out, TreeDiffEntry{ - Path: full, - Kind: TreeDiffEntryKindAdded, - Old: nil, - New: entry, - }) - - if entry.Mode == FileModeDir { - sub, err := repo.readTree(entry.ID) - if err != nil { - return err - } - if err := repo.diffTreesRecursive(nil, sub, full, out); err != nil { - return err - } - } - } - return nil - } - if b == nil { - for i := range a.Entries { - entry := &a.Entries[i] - full := joinPath(prefix, entry.Name) - - *out = append(*out, TreeDiffEntry{ - Path: full, - Kind: TreeDiffEntryKindDeleted, - Old: entry, - New: nil, - }) - - if entry.Mode == FileModeDir { - sub, err := repo.readTree(entry.ID) - if err != nil { - return err - } - if err := repo.diffTreesRecursive(sub, nil, full, out); err != nil { - return err - } - } - } - return nil - } - - left := make(map[string]*TreeEntry, len(a.Entries)) - for i := range a.Entries { - e := &a.Entries[i] - left[string(e.Name)] = e - } - right := make(map[string]*TreeEntry, len(b.Entries)) - for i := range b.Entries { - e := &b.Entries[i] - right[string(e.Name)] = e - } - - seen := make(map[string]bool, len(a.Entries)+len(b.Entries)) - for n := range left { - seen[n] = true - } - for n := range right { - seen[n] = true - } - - for name := range seen { - le := left[name] - re := right[name] - - full := joinPath(prefix, []byte(name)) - - switch { - case le == nil && re != nil: - *out = append(*out, TreeDiffEntry{ - Path: full, - Kind: TreeDiffEntryKindAdded, - Old: nil, - New: re, - }) - - if re.Mode == FileModeDir { - sub, err := repo.readTree(re.ID) - if err != nil { - return err - } - if err := repo.diffTreesRecursive(nil, sub, full, out); err != nil { - return err - } - } - - case le != nil && re == nil: - *out = append(*out, TreeDiffEntry{ - Path: full, - Kind: TreeDiffEntryKindDeleted, - Old: le, - New: nil, - }) - - if le.Mode == FileModeDir { - sub, err := repo.readTree(le.ID) - if err != nil { - return err - } - if err := repo.diffTreesRecursive(sub, nil, full, out); err != nil { - return err - } - } - - default: - modified := (le.Mode != re.Mode) || (le.ID != re.ID) - if modified { - *out = append(*out, TreeDiffEntry{ - Path: full, - Kind: TreeDiffEntryKindModified, - Old: le, - New: re, - }) - } - - if le.Mode == FileModeDir && re.Mode == FileModeDir && le.ID != re.ID { - ls, err := repo.readTree(le.ID) - if err != nil { - return err - } - rs, err := repo.readTree(re.ID) - if err != nil { - return err - } - if err := repo.diffTreesRecursive(ls, rs, full, out); err != nil { - return err - } - } - } - } - - return nil -} - -func joinPath(prefix, name []byte) []byte { - if len(prefix) == 0 { - out := make([]byte, len(name)) - copy(out, name) - return out - } - out := make([]byte, len(prefix)+1+len(name)) - copy(out, prefix) - out[len(prefix)] = '/' - copy(out[len(prefix)+1:], name) - return out -} - -func (repo *Repository) readTree(id Hash) (*StoredTree, error) { - obj, err := repo.ReadObject(id) - if err != nil { - return nil, err - } - tree, ok := obj.(*StoredTree) - if !ok { - return nil, ErrInvalidObject - } - return tree, nil -} |