format/diff: unified diff encoder and public API

- Added Patch interface
- Added a Unified Diff encoder from Patches
- Added Change method to generate Patches
- Added Changes method to generate Patches
- Added Tree method to generate Patches
- Added Commit method to generate Patches

1 files changed, 11 insertions, 0 deletions

diff --git a/plumbing/object/tree.go b/plumbing/object/tree.go
index 25687b0..512db9f 100644
--- a/plumbing/object/tree.go
+++ b/plumbing/object/tree.go
@@ -270,6 +270,17 @@ func (from *Tree) Diff(to *Tree) (Changes, error) {
 	return DiffTree(from, to)
 }
 
+// Patch returns a slice of Patch objects with all the changes between trees
+// in chunks. This representation can be used to create several diff outputs.
+func (from *Tree) Patch(to *Tree) (*Patch, error) {
+	changes, err := DiffTree(from, to)
+	if err != nil {
+		return nil, err
+	}
+
+	return changes.Patch()
+}
+
 // treeEntryIter facilitates iterating through the TreeEntry objects in a Tree.
 type treeEntryIter struct {
 	t   *Tree