t := ctx.Value(testingTBKey{})
	if t == nil {
		return nil, false
	}
	return t.(testing.TB), true
}

// initScriptDirs creates the initial directory structure in s for unpacking a
// cmd/go script.
func initScriptDirs(t testing.TB, s *script.State) (telemetryDir string) {
	must := func(err error) {
		if err != nil {
			t.Helper()
			t.Fatal(err)
		}
	}