wp_list_pages fails with meta_value=0 criteria

[Big Tick]

The following code will ignore the meta_key filtering. In other words, wp_list_pages can't test for a meta_value of 0.

wp_list_pages(
  array(
    'meta_key' => 'a_custom_key',
    'meta_value' => '0'
  )
)

[SergeyBiryukov]

Related: #15292

[nacin]

In 22445:

Fix meta value querying in wp_list_pages(). props SergeyBiryukov. fixes #20376.

[nacin]

In 22464:

Revert [22445]. see #20376. fixes #22389.

[nacin]

See #22389.

[rmccue]

No regression on wp_dropdown_pages(), looks good to me.

[kovshenin]

Refreshed 20376.3.patch​ and added unit tests for meta queries in get_pages and wp_dropdown_pages in 20376.tests.diff​.

[DrewAPicture]

Refresh.

[DrewAPicture]

20376.4.patch​ refreshes .3

[SergeyBiryukov]

In 1279/tests:

get_pages() test for '0' as meta_value argument and a basic wp_dropdown_pages() test. props kovshenin. see #20376.

[SergeyBiryukov]

In 24238:

Fix handling of '0' as meta_value argument in get_pages(). fixes #20376.