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Source code

function wp_update_term( $term_id, $taxonomy, $args = array() ) {

	global $wpdb;



	if ( ! taxonomy_exists($taxonomy) )

		return new WP_Error('invalid_taxonomy', __('Invalid taxonomy'));



	$term_id = (int) $term_id;



	// First, get all of the original args

	$term = get_term ($term_id, $taxonomy, ARRAY_A);



	if ( is_wp_error( $term ) )

		return $term;



	// Escape data pulled from DB.

	$term = add_magic_quotes($term);



	// Merge old and new args with new args overwriting old ones.

	$args = array_merge($term, $args);



	$defaults = array( 'alias_of' => '', 'description' => '', 'parent' => 0, 'slug' => '');

	$args = wp_parse_args($args, $defaults);

	$args = sanitize_term($args, $taxonomy, 'db');

	extract($args, EXTR_SKIP);



	// expected_slashed ($name)

	$name = stripslashes($name);

	$description = stripslashes($description);



	if ( '' == trim($name) )

		return new WP_Error('empty_term_name', __('A name is required for this term'));



	$empty_slug = false;

	if ( empty($slug) ) {

		$empty_slug = true;

		$slug = sanitize_title($name);

	}



	if ( $alias_of ) {

		$alias = $wpdb->get_row( $wpdb->prepare( "SELECT term_id, term_group FROM $wpdb->terms WHERE slug = %s", $alias_of) );

		if ( $alias->term_group ) {

			// The alias we want is already in a group, so let's use that one.

			$term_group = $alias->term_group;

		} else {

			// The alias isn't in a group, so let's create a new one and firstly add the alias term to it.

			$term_group = $wpdb->get_var("SELECT MAX(term_group) FROM $wpdb->terms") + 1;

			do_action( 'edit_terms', $alias->term_id );

			$wpdb->update( $wpdb->terms, compact('term_group'), array( 'term_id' => $alias->term_id ) );

			do_action( 'edited_terms', $alias->term_id );

		}

	}



	// Check $parent to see if it will cause a hierarchy loop

	$parent = apply_filters( 'wp_update_term_parent', $parent, $term_id, $taxonomy, compact( array_keys( $args ) ), $args );



	// Check for duplicate slug

	$id = $wpdb->get_var( $wpdb->prepare( "SELECT term_id FROM $wpdb->terms WHERE slug = %s", $slug ) );

	if ( $id && ($id != $term_id) ) {

		// If an empty slug was passed or the parent changed, reset the slug to something unique.

		// Otherwise, bail.

		if ( $empty_slug || ( $parent != $term['parent']) )

			$slug = wp_unique_term_slug($slug, (object) $args);

		else

			return new WP_Error('duplicate_term_slug', sprintf(__('The slug “%s” is already in use by another term'), $slug));

	}

	do_action( 'edit_terms', $term_id );

	$wpdb->update($wpdb->terms, compact( 'name', 'slug', 'term_group' ), compact( 'term_id' ) );

	if ( empty($slug) ) {

		$slug = sanitize_title($name, $term_id);

		$wpdb->update( $wpdb->terms, compact( 'slug' ), compact( 'term_id' ) );

	}

	do_action( 'edited_terms', $term_id );



	$tt_id = $wpdb->get_var( $wpdb->prepare( "SELECT tt.term_taxonomy_id FROM $wpdb->term_taxonomy AS tt INNER JOIN $wpdb->terms AS t ON tt.term_id = t.term_id WHERE tt.taxonomy = %s AND t.term_id = %d", $taxonomy, $term_id) );

	do_action( 'edit_term_taxonomy', $tt_id, $taxonomy );

	$wpdb->update( $wpdb->term_taxonomy, compact( 'term_id', 'taxonomy', 'description', 'parent' ), array( 'term_taxonomy_id' => $tt_id ) );

	do_action( 'edited_term_taxonomy', $tt_id, $taxonomy );



	do_action("edit_term", $term_id, $tt_id, $taxonomy);

	do_action("edit_$taxonomy", $term_id, $tt_id);



	$term_id = apply_filters('term_id_filter', $term_id, $tt_id);



	clean_term_cache($term_id, $taxonomy);



	do_action("edited_term", $term_id, $tt_id, $taxonomy);

	do_action("edited_$taxonomy", $term_id, $tt_id);



	return array('term_id' => $term_id, 'term_taxonomy_id' => $tt_id);

}