// +build ignore package strings_test import ( "strings" "testing" ) func TestIndex(t *testing.T) { for _, test := range []struct { s string sep string out int }{ {"", "", 0}, {"", "a", -1}, {"fo", "foo", -1}, {"foo", "foo", 0}, {"oofofoofooo", "f", 2}, // etc } { actual := strings.Index(test.s, test.sep) if actual != test.out { t.Errorf("Index(%q,%q) = %v; want %v", test.s, test.sep, actual, test.out) } } }