Default filter `doing_it_wrong_trigger_error` for REST request cause no notice at all.

[okvee]

File: wp-includes/rest-api.php inside function rest_api_default_filters() has this code.

if ( wp_is_serving_rest_request() ) {
    // ...
    add_filter( 'doing_it_wrong_trigger_error', '__return_false' );
}

With this filter, all wrong calling code will not showing the notice anywhere including in wp-content/debug.log.

For example:
Function register_rest_route() ( ​https://developer.wordpress.org/reference/functions/register_rest_route/ ). There are many detection to call _doing_it_wrong() to notice developer to know that they are doing it wrong and let them fix it. These notices are useful and some can improve security.

When I call function register_rest_route() without permission_callback argument, it should showing the notice about doing it wrong somewhere such as in debug.log.

But inside function _doing_it_wrong(), your if condition:

if ( WP_DEBUG && apply_filters( 'doing_it_wrong_trigger_error', true, $function_name, $message, $version ) )

calls to filter doing_it_wrong_trigger_error while this filter always return false. This cause function _doing_it_wrong() completely useless.

Please consider change this default filter value or make it at least write the "doing it wrong" notice to wp-content/debug.log file.

Tested with WordPress development version (6.9-RC1-61214).

[westonruter]

The code in question was added way back in r34928 (​b392114) when the REST API was first introduced in core. The intention was for the deprecation message to be sent back via the X-WP-DeprecatedFunction response header. But I don't see why it can't also be sent to the error log.

[iflairwebtechnologies]

We have checked and created one patch for this issue

Fixes #64260. The doing_it_wrong_trigger_error filter was preventing all doing_it_wrong notices from being logged during REST requests. This change ensures notices are written to debug.log while still preventing trigger_error() from interfering with REST responses.

Now the error is filterd but in the debug.log file you can see a meeesage like this:

[21-Nov-2025 14:01:41 UTC] REST API - Doing it wrong: register_rest_route - The REST API route definition for <code>test/v1/example</code> is missing the required <code>permission_callback</code> argument. For REST API routes that are intended to be public, use <code>return_true</code> as the permission callback. (This message was added in version 5.5.0.)

It looks like one of the GitHub Actions jobs failed due to a transient network issue (curl error 7 while downloading from packagist.org) and not because of my code changes.
Could someone please re-run the failed job? Thank you!

Could someone please re-run the failed job? Thank you!

Re-run!