Do not override pagination args if woocommerce_hpos_pre_query doesn't override query

[jorgeatorres]

Submission Review Guidelines:

• I have followed the WooCommerce Contributing Guidelines and the WordPress Coding Standards.
• I have checked to ensure there aren't other open Pull Requests for the same update/change.
• I have reviewed my code for security best practices.
• Following the above guidelines will result in quick merges and clear and detailed feedback when appropriate.

Changes proposed in this Pull Request:

In #39945 we introduced a filter (woocommerce_hpos_pre_query) that allows overriding of HPOS queries, but it currently sets internal pagination variables to NULL even when not actually being used:

woocommerce/plugins/woocommerce/src/Internal/DataStores/Orders/OrdersTableQuery.php

Line 233 in 8a6fcd8

list( $this->orders, $this->found_orders, $this->max_num_pages ) = apply_filters( 'woocommerce_hpos_pre_query', null, $this, $this->sql );

This is incorrect as those variables have default values (of 0) which should be preserved unless the query is, in fact, overridden.

Closes #40548.

How to test the changes in this Pull Request:

Using the WooCommerce Testing Instructions Guide, include your detailed testing instructions:

1. Start with HPOS enabled in WC > Settings > Advanced > Features.
2. Run the following snippet using WP-CLI (either wp run-eval or wp shell):

   wc_get_orders(
       [
    	   'status'   => 'all',
    	   'type'     => 'shop_order',
    	   'post__in' => [0],
    	   'limit'    => 1,
    	   'return'   => 'ids',
    	   'paginate' => true,
       ]
   );

3. Confirm that the output is as follows:

   stdClass Object(
      [orders] => Array()
      [total] => 0
      [max_num_pages] => 0
   )
   

   In particular, total and max_num_pages should be 0.
4. Go back to WC > Settings > Advanced > Features and disable HPOS.
5. Repeat step 2 and confirm that the output is again that of step 3.

Changelog entry

• Automatically create a changelog entry from the details below.

Significance

• Patch
• Minor
• Major

Type

• Fix - Fixes an existing bug
• Add - Adds functionality
• Update - Update existing functionality
• Dev - Development related task
• Tweak - A minor adjustment to the codebase
• Performance - Address performance issues
• Enhancement - Improvement to existing functionality

Message

Comment

[github-actions]

Hi @barryhughes,

Apart from reviewing the code changes, please make sure to review the testing instructions as well.

You can follow this guide to find out what good testing instructions should look like:
https://github.com/woocommerce/woocommerce/wiki/Writing-high-quality-testing-instructions

[github-actions]

Test Results Summary

Commit SHA: 17f81d1

Test 🧪	Passed ✅	Failed 🚨	Broken 🚧	Skipped ⏭️	Unknown ❔	Total 📊	Duration ⏱️
API Tests	259	0	0	2	0	261	1m 0s
E2E Tests	212	0	0	7	0	219	24m 8s

---

To view the full API test report, click here.
To view the full E2E test report, click here.
To view all test reports, visit the WooCommerce Test Reports Dashboard.

[barryhughes]

I don't think it really matters, but we could simplify this to:

Suggested change

	add_filter( 'woocommerce_hpos_pre_query', '__return_null', 10, 3 );
	add_filter( 'woocommerce_hpos_pre_query', '__return_null' );

[barryhughes]

Looks good!

• Straightforward change, tests well locally when invoking it via wp eval.
• Confirmed the order list table is not impacted by this change (the filter and the condition following it are invoked when accessing this screen) and that pagination continues to work as expected.
• I don't think there is a need for further analysis in this case, so will merge directly.