On callback URL no JSON field "code" is being returned

[kontur]

After the redirect at this step:

´´´
$request_object = $oauth->auth('the_provider', array(
'redirect' => true
));
´´´

I get error messages and in investigations I traced the problem to src/OAuth_io/OAuth.php line 148:

$code = $data['data']['code'];

When I dump the parsed JSON there is no field code, but there is access_token. Did the returned encoded JSON change? I also tried just setting $code to access_token to verify, but ran into other complications, so I am asking the maintainers here for more informed input.

[kontur]

Have you had any chance to check this?