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go/src/infra/libs/gitiles/commit_diff.go

+// 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 gitiles
+
+import (
+        "strings"
+
+        "infra/libs/git"
+)
+
+// GetCommitDiff returns the git.TreeDiff from the given committish.
+func (g *Gitiles) GetCommitDiff(committish string) (git.TreeDiff, error) {
+        rslt, err := g.JSON(jsonCommitDiff{}, "+", committish)
+        if err != nil {
+                return nil, err
+        }
+        diff := *rslt.(*jsonCommitDiff)
+        return diff.ToResult(), nil
+}
+
+func (g *Gitiles) GetTextCommitDiff(id git.ObjectID) (string, error) {
+        rslt, err := g.Text("+", id.String()+"^!")
+        if err != nil {
+                return "", err
+        }
+        return string(rslt), nil
+}
+
+// private
+
+type jsonCommitDiff struct {
+        TreeDiff []struct {
+                Type    string   `json:"type"`
+                OldID   string   `json:"old_id"`
+                OldMode git.Mode `json:"old_mode"`
+                OldPath string   `json:"old_path"`
+                NewID   string   `json:"new_id"`
+                NewMode git.Mode `json:"new_mode"`
+                NewPath string   `json:"new_path"`
+        } `json:"tree_diff"`
+}
+
+func (c *jsonCommitDiff) ToResult() git.TreeDiff {
+        td := make(git.TreeDiff, 0, len(c.TreeDiff))
+        for _, ent := range c.TreeDiff {
+                td = append(td, git.TreeDiffEntry{
+                        Action: strings.ToUpper(ent.Type[:1]),
+                        Old: git.TreeDiffEntryHalf{
+                                Child: *git.NewEmptyChild(ent.OldMode, git.MakeObjectID(ent.OldID)),
+                                Name:  ent.OldPath,
+                        },
+                        New: git.TreeDiffEntryHalf{
+                                Child: *git.NewEmptyChild(ent.NewMode, git.MakeObjectID(ent.NewID)),
+                                Name:  ent.NewPath,
+                        },
+                })
+        }
+        return td
+}