Introduce a general `pre_option` filter in `get_option()`

[flixos90]

We currently have a pre_option_{$option} filter in get_option() to short-circuit the process of retrieving an option. I think it would make sense to also add a global filter pre_option, similar like we have in update_option().

[flixos90]

37930.diff​ adds a filter pre_get_option. It works similar like the new filters proposed in #37928 and #37929 respectively.

[NathanAtmoz]

I think this makes sense. I just have a question about the order.

The get_option() function filters pre_update_option_{$option} before pre_update_option, so would it make more sense to keep the same order in get_option()?

[desrosj]

Made an adjustment on the patch. The filter above it checks for false !== $value where the first patch checked for ! is_null(). Changed that for consistency.

Also, updated the PHPDocblock to reflect 4.8.0, and fix a typo.

[desrosj]

I looked at this one first of the three, of course (#37929 and #37928), and the other two check for null.

I did some digging because I feel like most of the "short circuit" filters I have used in core have a truthy check for false !== $value instead of null. It seems there is a pretty equal number throughout core for each. Here are some examples.

Truthy check

• Shortcodes: https://core.trac.wordpress.org/browser/trunk/src/wp-includes/shortcodes.php#L338
• pre_get_lastpostmodified: https://core.trac.wordpress.org/browser/trunk/src/wp-includes/post.php#L5571
• pre_option_{$option} above current new filter.
• pre_site_option_{$option}: https://core.trac.wordpress.org/browser/trunk/src/wp-includes/option.php#L1124
• pre_site_transient_{$transient}: https://core.trac.wordpress.org/browser/trunk/src/wp-includes/option.php#L1594
• pre_transient_{$transient}: https://core.trac.wordpress.org/browser/trunk/src/wp-includes/option.php#L641
• When retrieving WP_Cache items this is appropriate.

Locations using a null !== $value check:

• wp_save_image_editor_file: https://core.trac.wordpress.org/browser/trunk/src/wp-admin/includes/image-edit.php#L317
• wp_save_image_file: https://core.trac.wordpress.org/browser/trunk/src/wp-admin/includes/image-edit.php#L344
• 'pre_get_table_charset': https://core.trac.wordpress.org/browser/trunk/src/wp-includes/wp-db.php#L2451
• pre_get_blogs_of_user: https://core.trac.wordpress.org/browser/trunk/src/wp-includes/user.php?rev=37326#L594
• pre_delete_post: https://core.trac.wordpress.org/browser/trunk/src/wp-includes/post.php#L2446

I think that we should at least remain consistent in the options API.

Looking through options.php, I see the following:

Truthy checks already in core:

• pre_site_transient_{$transient}
• pre_option_{$option}
• pre_get_option - addressed in this patch
• pre_transient_{$transient},
• pre_site_option_{$option}

There are currently only two null !== $value or ! is_null() checks in options.php, and both follow database queries that more than likely return null.

I vote for false !== checks, unless there are reasons why null is beter that I don't know of.

[spacedmonkey]

Updated this patch with another solution. Consider the following code in update_option

        $value = apply_filters( "pre_update_option_{$option}", $value, $old_value, $option );

        /**
         * Filters an option before its value is (maybe) serialized and updated.
         *
         * @since 3.9.0
         *
         * @param mixed  $value     The new, unserialized option value.
         * @param string $option    Name of the option.
         * @param mixed  $old_value The old option value.
         */
        $value = apply_filters( 'pre_update_option', $value, $option, $old_value );

It passes the value through both filters. I have updated my patch so follow this patten. My patch passes the variable through the pre_get_option second and uses the existing return.

[johnjamesjacoby]

Related: #39286

[sc0ttkclark]

I'd like to also see general filters implemented for default_option in get_option() as well, used in three potential places for return there.

[SergeyBiryukov]

#41576 was marked as a duplicate.

[SergeyBiryukov]

#56045 was marked as a duplicate.

Reash and added test

Trac ticket: https://core.trac.wordpress.org/ticket/37930

[joyously]

Does this play nice with the Customizer?

[davidbaumwald]

@spacedmonkey Is this still on your list to commit before 6.1 Beta 1? I am happy to commit this around the same time as #56045, since they are very similar.

[spacedmonkey]

@davidbaumwald if you want to commit, go for it.

[davidbaumwald]

In 54145:

Options, Meta APIs: Add a new pre-option filter.

Although a pre_option_{$option} filter already exists, this change adds a more general pre_option filter that will run on every get_option call. This brings the control flow into similar flow as update_option.

Props flixos90, NathanAtmoz, desrosj, spacedmonkey, pbearne.
Fixes #37930.

Merged into core in https://core.trac.wordpress.org/changeset/54145.

[SergeyBiryukov]

In 54147:

Tests: Rename the test for pre_option filter to match the filter name.

Move the method to a more appropriate place, next to the test for default_option_* filter.

Follow-up to [54145].

See #37930.

[milana_cap]

This one can either go into grouped Dev note or just in Field guide.

[Drivingralle]

Next step #56870?