Remove extraneous newline

diff/diff.go

@@ -38,7 +38,7 @@ func Diff(A, B string) string {
 			fmt.Fprintf(buf, " %s\n", line)
 		}
 	}
-	return buf.String()
+	return strings.TrimRight(buf.String(), "\n")
 }
 
 // DiffChunks uses an O(D(N+M)) shortest-edit-script algorithm

pretty/util_test.go

@@ -44,8 +44,7 @@ func TestDiff(t *testing.T) {
             "Trillian",
 -           "Marvin",
            ],
- }
-`,
+ }`,
 		},
 	}