Recurly\Pager::key(): Return value must be of type mixed, none returned

[davedevelopment]

Describe the bug

The Pager implements the Iterator interface, but does not meet the contract. If this is a limitation, it could be noted in the docblock comments.

To Reproduce

    // Pager_Test.php

     public function testIteratorComaptability(): void                                                                                                                                                                                                                       
     {                                                                                                                                                                                                                                                                       
         $array = iterator_to_array($this->pager);                                                                                                                                                                                                                           
                                                                                                                                                                                                                                                                             
         $this->assertEquals(3, count($array));                                                                                                                                                                                                                              
     }

1) PagerTest::testIteratorComaptability
TypeError: Recurly\Pager::key(): Return value must be of type mixed, none returned

/home/davem/src/recurly-client-php/lib/recurly/pager.php:113
/home/davem/src/recurly-client-php/tests/Pager_Test.php:138

Expected behavior

iterator_to_array($pager) to return an array or the documentation to make it clear that the Pager is not actually an Iterator etc.

Your Environment

• Which version of this library are you using?

davem@wes:recurly-client-php:v3-v2021-02-25$ git rev-parse HEAD
1a02d110b61a77163027156f574f494fb8c0305e

• Which version of php are you using?

davem@wes:recurly-client-php:v3-v2021-02-25$ php -v
PHP 8.2.8 (cli) (built: Jul 21 2023 11:32:32) (NTS)
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