Filters and actions have been the basis of WordPress' plugin functionality since time immemorial, they've always been a reliable method for acting upon the current state of WordPress, and will continue to be so.
Over the years, however, edge cases have cropped up. Particularly when it comes to recursively executing hooks, or a hook adding and removing itself, the existing implementation struggled to keep up with more complex use cases.
And so, we introduce `WP_Hook`. By changing `$wp_filter` from an array of arrays, to an array of objects, we reduce the complexity of the hook handling code, as the processing code (see `::apply_filters()`) only needs to be aware of itself, rather than the state of all hooks. At the same time, we're able te handle more complex use cases, as the object can more easily keep track of its own state than an array ever could.
Props jbrinley for the original architecture and design of this patch.
Props SergeyBiryukov, cheeserolls, Denis-de-Bernardy, leewillis77, wonderboymusic, nacin, jorbin, DrewAPicture, ocean90, dougwollison, khag7, pento, noplanman and aaroncampbell for their testing, suggestions, contributions, patch maintenance, cajoling and patience as we got through this.
Fixes#17817.
git-svn-id: https://develop.svn.wordpress.org/trunk@38571 602fd350-edb4-49c9-b593-d223f7449a82
First added in [37588] and later modified in [38224], the idea was to ensure that filters/actions added before `advance-cache.php` would not disappear if `advance-cache.php` overloaded the filters/actions with code such as `$wp_filter = array()`. This is an edge case and one that there is no documented case of existing.
This restores the behavior from WordPress 4.5 and before. It is strongly encouraged that developers using `advance-cache.php` to use the Plugins API that is available before the loading of `advance-cache.php` rather than directly interacting with any of the globals.
Props azaozz, jorbin, dd32 for review, pento for review, westi for investigation, ipstenu for research.
See #36819.
git-svn-id: https://develop.svn.wordpress.org/trunk@38251 602fd350-edb4-49c9-b593-d223f7449a82
[37588] added methods to backup the plugin globals, for ensuring that advanced cache drop-ins don't overwrite hooks that've been added earlier in the load process.
The method for restoring the plugin globals wasn't compatible with the implementation of `WP_Hook` in #17817. `WP_Hook` implements `ArrayAccess`, so `_restore_plugin_globals()` was treating it as an array, and inadvertantly overwriting the `WP_Hook` object with a plain array.
To avoid having to re-write this code as part of #17817, we now use `add_filter()` to restore any hooks that were added by cache drop-ins, which `WP_Hook` correctly supports.
Props pento, jorbin.
See #36819.
git-svn-id: https://develop.svn.wordpress.org/trunk@38223 602fd350-edb4-49c9-b593-d223f7449a82
When a filter or action hook is deprecated, the corresponding `apply_filters()`
or `do_action()` calls should be switched out with `apply_filters_deprecated()`
or `do_action_deprecated()`. The latter functions will throw a deprecation
before invoking the original hook.
Props solarissmoke, SergeyBiryukov, DrewAPicture.
Fixes#10441.
git-svn-id: https://develop.svn.wordpress.org/trunk@37861 602fd350-edb4-49c9-b593-d223f7449a82
In order to allow non-web initializations of WordPress (such as through wp-cli) to modify things like the check for maintenance mode, plugins.php and the associated functions must be available much earlier. The use of these functions earlier than the loading of plugins is not recommended in most use cases.
Fixes#36819. See #34936.
Props jorbin, danielbachhuber for documentation.
git-svn-id: https://develop.svn.wordpress.org/trunk@37588 602fd350-edb4-49c9-b593-d223f7449a82
did_action() returns true the moment a hook is initially run, leaving you no way to tell if the hook is still in progress. Hooks can be nested and this checks the entire stack, versus current_filter() which only identifies the final hook in the stack. This commit also introduces current_action() for parity.
To tell if a hook has completed, one can use did_action() and ! doing_action() together.
The functions do not require an argument. In that situation, they indicate whether the stack is empty.
props ericmann for the initial unit tests.
fixes#14994.
git-svn-id: https://develop.svn.wordpress.org/trunk@27294 602fd350-edb4-49c9-b593-d223f7449a82
wp-tests-config.php can/should reside in the root of a develop checkout. `phpunit` should be run from the root.
see #25088.
git-svn-id: https://develop.svn.wordpress.org/trunk@25165 602fd350-edb4-49c9-b593-d223f7449a82
