vlib/v/checker/tests/assign_var_redefinition_err.vv:6:2: error: redefinition of `aaaa`
    4 | 
    5 | fn test(aaaa string) string {
    6 |     aaaa := 'bbbb' + aaaa
      |     ~~~~
    7 |     return aaaa
    8 | }