type Btest … var Btests … func init() { … } func check(t *testing.T, str string, lcs lcs, want []string) { … } func checkDiffs(t *testing.T, before string, diffs []Diff, after string) { … } func lcslen(l lcs) int { … } // return a random string of length n made of characters from s func randstr(s string, n int) string { … } func TestLcsFix(t *testing.T) { … }