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

+package gitiles
+
+import "strings"
+
+import "infra/libs/git"
+
+// CommitDiffResult contains a git.TreeDiff, or an error.
+type CommitDiffResult struct {
+        Err  error
+        Diff git.TreeDiff
+}
+
+type TextCommitDiffResult struct {
+        Err  error
+        Diff []string
+}
+
+// GetCommitDiff returns the CommitDiffResult from the given committish.
+func (g *Gitiles) GetCommitDiff(committish string) CommitDiffResult {
+        rslt := <-g.JSON(jsonCommitDiff{}, "+", committish)
+        if rslt.Err != nil {
+                return CommitDiffResult{Err: rslt.Err}
+        }
+        diff := *rslt.DataPtr.(*jsonCommitDiff)
+        return diff.ToResult()
+}
+
+func (g *Gitiles) GetTextCommitDiff(id git.ObjectID) TextCommitDiffResult {
+        rslt := <-g.Text("+", id.String()+"^!")
+        if rslt.Err != nil {
+                return TextCommitDiffResult{Err: rslt.Err}
+        }
+        return TextCommitDiffResult{Diff: strings.Split(string(rslt.Data), "\n")}
+}
+
+// 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() CommitDiffResult {
+        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 CommitDiffResult{Diff: td}
+}