wp_save_post_revision( int $post_id ): int|WP_Error|void

Description

Compatibility

Present in every tracked release (6.7.7 to 7.1.0), and compiles on PHP 7.4 through 8.6-dev.

Parameters

$post_idint

The ID of the post to save as a revision.

Return value

int|WP_Error|void

Void or 0 if error, new revision ID, if success.

Performance profile

How much work a call to wp_save_post_revision() does, and what it touches: the algorithmic scaling, the Zend instruction count per call across PHP versions, the hooks it hands control to, and the core code that calls it. Measured from the compiled opcodes, not a stopwatch, so every number is identical on any machine running the same PHP version, and every function in core is ranked by cost.

Cost class

Heavy

Reaches the database via get_post().

Scaling

Scales with input

The body loops, so the work grows with what you pass in.

Instructions

6–124

Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 144.

Plugin surface

3 hooks

Third-party callbacks on 'wp_save_post_revision_check_for_changes', 'wp_save_post_revision_post_has_changed', 'wp_save_post_revision_revisions_before_deletion' run inside this call, and their cost is not bounded by anything here.

Called by

3

3 places in core call this, so the cost is paid more often than your own code shows.

What it touches

• querycontent queryget_post()called directly
• hookthird-party callbacksapply_filters()called directly

Further down the call graph this can also reach option, cache, serialize and transient. Those are the worst case, several calls deep and usually down an error path, not what a normal call pays.

What one call costs · 36 distinct outcomes

One number would be a lie: the work depends on which branch runs. These are every distinct cost wp_save_post_revision() can have, taken from its control-flow graph on PHP 8.5.

Hooks and filters fired · 3

3 hooks fire while wp_save_post_revision() runs, in this order:

1. 1
   apply_filters( wp_save_post_revision_check_for_changes )filterline 186 (+56 into the body)

   Filters whether the post has changed since the latest revision.

2. 2
   apply_filters( wp_save_post_revision_post_has_changed )filterline 208 (+78 into the body)

   Filters whether a post has changed.

3. 3
   apply_filters( wp_save_post_revision_revisions_before_deletion )filterline 239 (+109 into the body)

   Filters the revisions to be considered for deletion.

Uses · 13

• doing_action()Returns whether or not an action hook is currently being processed.
• has_action()Checks if any action has been registered for a hook.
• get_post()Retrieves post data given a post ID or post object.
• post_type_supports()Checks a post type's support for a given feature.
• wp_revisions_enabled()Determines whether revisions are enabled for a given post.
• wp_get_post_revisions()Returns all revisions of specified post.
• str_contains()Polyfill for `str_contains()` function added in PHP 8.0.
• apply_filters()Calls the callback functions that have been added to a filter hook.
• _wp_post_revision_fields()Determines which fields of posts are to be saved in revisions.
• normalize_whitespace()Normalizes EOL characters and strips duplicate whitespace.
• _wp_put_post_revision()Inserts post data into the posts table as a post revision.
• wp_revisions_to_keep()Determines how many revisions to retain for a given post.

Used by · 3

• _wp_upgrade_revisions_of_post()Upgrades the revisions author, adds the current post as a revision and sets the revisions version to 1.
• wp_save_post_revision_on_insert()Saves revisions for a post after all changes have been made.
• wp_update_custom_css_post()Updates the `custom_css` post for a given theme.

Source code

View on Trac ↗View on GitHub ↗

130function wp_save_post_revision( $post_id ) {131	if ( defined( 'DOING_AUTOSAVE' ) && DOING_AUTOSAVE ) {132		return;133	}134 135	// Prevent saving post revisions if revisions should be saved on wp_after_insert_post.136	if ( doing_action( 'post_updated' ) && has_action( 'wp_after_insert_post', 'wp_save_post_revision_on_insert' ) ) {137		return;138	}139 140	$post = get_post( $post_id );141 142	if ( ! $post ) {143		return;144	}145 146	if ( ! post_type_supports( $post->post_type, 'revisions' ) ) {147		return;148	}149 150	if ( 'auto-draft' === $post->post_status ) {151		return;152	}153 154	if ( ! wp_revisions_enabled( $post ) ) {155		return;156	}157 158	/*159	 * Compare the proposed update with the last stored revision verifying that160	 * they are different, unless a plugin tells us to always save regardless.161	 * If no previous revisions, save one.162	 */163	$revisions = wp_get_post_revisions( $post_id );164	if ( $revisions ) {165		// Grab the latest revision, but not an autosave.166		foreach ( $revisions as $revision ) {167			if ( str_contains( $revision->post_name, "{$revision->post_parent}-revision" ) ) {168				$latest_revision = $revision;169				break;170			}171		}172 173		/**174		 * Filters whether the post has changed since the latest revision.175		 *176		 * By default a revision is saved only if one of the revisioned fields has changed.177		 * This filter can override that so a revision is saved even if nothing has changed.178		 *179		 * @since 3.6.0180		 *181		 * @param bool    $check_for_changes Whether to check for changes before saving a new revision.182		 *                                   Default true.183		 * @param WP_Post $latest_revision   The latest revision post object.184		 * @param WP_Post $post              The post object.185		 */186		if ( isset( $latest_revision ) && apply_filters( 'wp_save_post_revision_check_for_changes', true, $latest_revision, $post ) ) {187			$post_has_changed = false;188 189			foreach ( array_keys( _wp_post_revision_fields( $post ) ) as $field ) {190				if ( normalize_whitespace( $post->$field ) !== normalize_whitespace( $latest_revision->$field ) ) {191					$post_has_changed = true;192					break;193				}194			}195 196			/**197			 * Filters whether a post has changed.198			 *199			 * By default a revision is saved only if one of the revisioned fields has changed.200			 * This filter allows for additional checks to determine if there were changes.201			 *202			 * @since 4.1.0203			 *204			 * @param bool    $post_has_changed Whether the post has changed.205			 * @param WP_Post $latest_revision  The latest revision post object.206			 * @param WP_Post $post             The post object.207			 */208			$post_has_changed = (bool) apply_filters( 'wp_save_post_revision_post_has_changed', $post_has_changed, $latest_revision, $post );209

Changelog

Introduced in 2.6.0. One change between 6.7.7 and 7.1.0.

1. 6.7.7
2. 6.8.8
3. 6.9.7
4. 7.0.4
5. 7.1.0

Signature, return type and hooks compared across 5 parsed releases.

About this page

Parsed data

Generated from the wordpress-develop 6.9.7 tag, from src/wp-includes/revision.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.

Corrections

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