All Settings page (options.php), message when saved

[ishitaka]

Even if saving fails beyond the number of items limit (max_input_vars) in the All Settings page (/wp-admin/options.php), it will be displayed as "Settings saved." It is necessary to display an error message.

(Related to the discussion in #25939)

[jorbin]

It would be great to get this fixed. Once there is a patch to discuss, we should move it into the relevant milestone.

[ishitaka]

Sorry, 45438.patch is a mistake.

[maguijo]

Trunk still has a pre-gutenberg version so I think I should wait until it updates to test this?

While I'm waiting, as a newbie, may I ask how I'm going to get a save error in order to test that your patch works properly? Or do I just need to edit and save a post a few times to be sure it doesn't cause problems?

[pento]

Needs testing and review.

[peterwilsoncc]

45438.2.patch​ looks good, 45438.diff​ is identical with a minor coding standards fix.

Testing notes

System
WordPress 6.0-alpha-52448-src
PHP-FPM 7.4
nginx

PHP Config: max_input_vars set to 10.

Before

• Saving wp-admin/options.php shows as successful
• Database did not update due to exceeding max_input_vars

After

• Saving wp-admin/options.php shows an error message
• Behaviour unchanged after removing change to max_input_vars

✓ working as expected

[peterwilsoncc]

In 53151:

Options: Show error when updating all options exceeds max_input_vars.

On sites with a large number of options, the number of inputs when saving all options via the /wp-admin/options.php page may exceed PHP's max_input_vars setting, this will prevent saving.

An error is now shown if this is the case.

Props ishitaka, jorbin, maguijo, pento, sergeybiryukov.
Fixes #45438.