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go/src/infra/libs/git/treeDiff.go

Index: go/src/infra/libs/git/treeDiff.go
diff --git a/go/src/infra/libs/git/treeDiff.go b/go/src/infra/libs/git/treeDiff.go
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index 0000000000000000000000000000000000000000..24bc4d457533f2dff065506b00255962d8245f6c
--- /dev/null
+++ b/go/src/infra/libs/git/treeDiff.go
@@ -0,0 +1,44 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package git
+
+import (
+	"fmt"
+)
+
+// Types ///////////////////////////////////////////////////////////////////////
+
+// TreeDiff represents the difference between two Treeish objects
+type TreeDiff []TreeDiffEntry
+
+// TreeDiffEntry represents the before and after of one path in the repo.
+// Note that the Old.Name and New.Name may be different if this item was
+// Moved or Copied.
+type TreeDiffEntry struct {
+	// Action is one of "ACDMRTUX"
+	// U is for unmerged... if you're just comparing trees you should never see this
+	// X is probably a bug in git... you should also never see this.
+	// T is a type change, so if a tree turned into a blob, for example
+	Action string
+
+	// For Action types 'R' or 'C', what percentage (from 0-100) are the old and
+	// new blobs similar.
+	Similarity int
+
+	Old TreeDiffEntryHalf
+	New TreeDiffEntryHalf
+}
+
+// TreeDiffEntryHalf is one entry in a TreeDiffEntry, either the Old or New half.
+type TreeDiffEntryHalf struct {
+	Child
+	Name string
+}
+
+// Member functions ////////////////////////////////////////////////////////////
+
+func (t *TreeDiffEntryHalf) String() string {
+	return fmt.Sprintf("%s: %s", t.Name, t.Child)
+}