func split(s, sep string) (string, string) {
	before, after, _ := strings.Cut(s, sep)
	return strings.TrimSpace(before), strings.TrimSpace(after)
}

func TestCheckExpr(t *testing.T) {
	testenv.MustHaveGoBuild(t)

	// Each comment has the form /* expr => object */:
	// expr is an identifier or selector expression that is passed