[wp-trac] [WordPress Trac] #63106: The loop can throw warning if `WP_Query::have_posts()` not called.

[WordPress Trac]

#63106: The loop can throw warning if `WP_Query::have_posts()` not called.
---------------------------+-----------------------------
 Reporter:  peterwilsoncc  |      Owner:  (none)
     Type:  defect (bug)   |     Status:  new
 Priority:  low            |  Milestone:  Awaiting Review
Component:  Query          |    Version:
 Severity:  normal         |   Keywords:
  Focuses:                 |
---------------------------+-----------------------------
 Starting or overrunning the loop can throw a warning if
 `WP_Query::have_posts()` is not called correctly via the developer. The
 issue can be seen in these tests:

 {{{#!php
 <?php
 function test_no_posts() {
         $query = new WP_Query( array( 'post_type' => 'unregistered_cpt' )
 );

         $query->the_post();
         $this->assertEmpty( $query->posts );
 }

 function test_too_many_calls() {
         $post_id = $this->factory()->post->create();
         $query   = new WP_Query( array( 'p' => $post_id ) );

         // Call the post twice.
         $query->the_post();
         $query->the_post();
         $this->assertNotEmpty( $query->posts );
 }
 }}}

 In each case the tests will throw an error before reaching the assertion,
 as they are attempting to access an array key that does not exist.

 A part of me is tempted to close this as wontfix, as it's very clearly
 documented that one should use `while ( have_posts() )` for the primary
 loop or `while $query->have_posts()` for a secondary loop.

-- 
Ticket URL: <https://core.trac.wordpress.org/ticket/63106>
WordPress Trac <https://core.trac.wordpress.org/>
WordPress publishing platform