WordPress/wp-includes/class-wp-list-util.php
Dominik Schilling 7cce73a634 General: Introduce a wp_list_sort() helper function, v2.
In addition to `wp_list_filter()` for filtering a list of objects, and `wp_list_pluck()` for plucking a certain field out of each object in a list, this new function can be used for sorting a list of objects by specific fields. These functions are now all contained within the new `WP_List_Util()` class and `wp_list_sort()` is used in various parts of core for sorting lists.

This was previously committed in [38859] but got reverted in [38862] and [38863]. To fix the previous issues, `wp_list_sort()` supports now an additional argument to preserve array keys via `uasort()`.

Props flixos90, DrewAPicture, jorbin.
Fixes #37128.
Built from https://develop.svn.wordpress.org/trunk@38928


git-svn-id: http://core.svn.wordpress.org/trunk@38871 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2016-10-25 21:26:32 +00:00

268 lines
6.3 KiB
PHP

<?php
/**
* WordPress List utility class
*
* @package WordPress
* @since 4.7.0
*/
/**
* List utility.
*
* Utility class to handle operations on an array of objects.
*
* @since 4.7.0
*/
class WP_List_Util {
/**
* The input array.
*
* @since 4.7.0
* @access private
* @var array
*/
private $input = array();
/**
* The output array.
*
* @since 4.7.0
* @access private
* @var array
*/
private $output = array();
/**
* Temporary arguments for sorting.
*
* @since 4.7.0
* @access private
* @var array
*/
private $orderby = array();
/**
* Constructor.
*
* Sets the input array.
*
* @since 4.7.0
*
* @param array $input Array to perform operations on.
*/
public function __construct( $input ) {
$this->output = $this->input = $input;
}
/**
* Returns the original input array.
*
* @since 4.7.0
* @access public
*
* @return array The input array.
*/
public function get_input() {
return $this->input;
}
/**
* Returns the output array.
*
* @since 4.7.0
* @access public
*
* @return array The output array.
*/
public function get_output() {
return $this->output;
}
/**
* Filters the list, based on a set of key => value arguments.
*
* @since 4.7.0
*
* @param array $args Optional. An array of key => value arguments to match
* against each object. Default empty array.
* @param string $operator Optional. The logical operation to perform. 'AND' means
* all elements from the array must match. 'OR' means only
* one element needs to match. 'NOT' means no elements may
* match. Default 'AND'.
* @return array Array of found values.
*/
public function filter( $args = array(), $operator = 'AND' ) {
if ( empty( $args ) ) {
return $this->output;
}
$operator = strtoupper( $operator );
if ( ! in_array( $operator, array( 'AND', 'OR', 'NOT' ), true ) ) {
return array();
}
$count = count( $args );
$filtered = array();
foreach ( $this->output as $key => $obj ) {
$to_match = (array) $obj;
$matched = 0;
foreach ( $args as $m_key => $m_value ) {
if ( array_key_exists( $m_key, $to_match ) && $m_value == $to_match[ $m_key ] ) {
$matched++;
}
}
if (
( 'AND' == $operator && $matched == $count ) ||
( 'OR' == $operator && $matched > 0 ) ||
( 'NOT' == $operator && 0 == $matched )
) {
$filtered[$key] = $obj;
}
}
$this->output = $filtered;
return $this->output;
}
/**
* Plucks a certain field out of each object in the list.
*
* This has the same functionality and prototype of
* array_column() (PHP 5.5) but also supports objects.
*
* @since 4.7.0
*
* @param int|string $field Field from the object to place instead of the entire object
* @param int|string $index_key Optional. Field from the object to use as keys for the new array.
* Default null.
* @return array Array of found values. If `$index_key` is set, an array of found values with keys
* corresponding to `$index_key`. If `$index_key` is null, array keys from the original
* `$list` will be preserved in the results.
*/
public function pluck( $field, $index_key = null ) {
if ( ! $index_key ) {
/*
* This is simple. Could at some point wrap array_column()
* if we knew we had an array of arrays.
*/
foreach ( $this->output as $key => $value ) {
if ( is_object( $value ) ) {
$this->output[ $key ] = $value->$field;
} else {
$this->output[ $key ] = $value[ $field ];
}
}
return $this->output;
}
/*
* When index_key is not set for a particular item, push the value
* to the end of the stack. This is how array_column() behaves.
*/
$newlist = array();
foreach ( $this->output as $value ) {
if ( is_object( $value ) ) {
if ( isset( $value->$index_key ) ) {
$newlist[ $value->$index_key ] = $value->$field;
} else {
$newlist[] = $value->$field;
}
} else {
if ( isset( $value[ $index_key ] ) ) {
$newlist[ $value[ $index_key ] ] = $value[ $field ];
} else {
$newlist[] = $value[ $field ];
}
}
}
$this->output = $newlist;
return $this->output;
}
/**
* Sorts the list, based on one or more orderby arguments.
*
* @since 4.7.0
*
* @param string|array $orderby Optional. Either the field name to order by or an array
* of multiple orderby fields as $orderby => $order.
* @param string $order Optional. Either 'ASC' or 'DESC'. Only used if $orderby
* is a string.
* @param bool $preserve_keys Optional. Whether to preserve keys. Default false.
* @return array The sorted array.
*/
public function sort( $orderby = array(), $order = 'ASC', $preserve_keys = false ) {
if ( empty( $orderby ) ) {
return $this->output;
}
if ( is_string( $orderby ) ) {
$orderby = array( $orderby => $order );
}
foreach ( $orderby as $field => $direction ) {
$orderby[ $field ] = 'DESC' === strtoupper( $direction ) ? 'DESC' : 'ASC';
}
$this->orderby = $orderby;
if ( $preserve_keys ) {
uasort( $this->output, array( $this, 'sort_callback' ) );
} else {
usort( $this->output, array( $this, 'sort_callback' ) );
}
$this->orderby = array();
return $this->output;
}
/**
* Callback to sort the list by specific fields.
*
* @since 4.7.0
* @access private
*
* @see WP_List_Util::sort()
*
* @param object|array $a One object to compare.
* @param object|array $b The other object to compare.
* @return int 0 if both objects equal. -1 if second object should come first, 1 otherwise.
*/
private function sort_callback( $a, $b ) {
if ( empty( $this->orderby ) ) {
return 0;
}
$a = (array) $a;
$b = (array) $b;
foreach ( $this->orderby as $field => $direction ) {
if ( ! isset( $a[ $field ] ) || ! isset( $b[ $field ] ) ) {
continue;
}
if ( $a[ $field ] == $b[ $field ] ) {
continue;
}
$results = 'DESC' === $direction ? array( 1, -1 ) : array( -1, 1 );
if ( is_numeric( $a[ $field ] ) && is_numeric( $b[ $field ] ) ) {
return ( $a[ $field ] < $b[ $field ] ) ? $results[0] : $results[1];
}
return 0 > strcmp( $a[ $field ], $b[ $field ] ) ? $results[0] : $results[1];
}
return 0;
}
}