WORDPRESS : Remove from the urls the prefix /custom-post-name/ in all my articles AND THEIR TRANSLATIONS made with Polylang - wordpress

Question

My theme was tailor-made by a developper.
All my (single-post) articles are custom posts.
By default the url of a custom post is : https://www.example.com/custom-post-name/slug
For very good reasons this prefix /custom-post-name/ had to be removed.
The developper of my theme achieved that by editing some code in the file declaring the custom post which is this one : wp-content/themes/mytheme/inc/custom-post-types.php
The custom-post-name as registered in this file is "article"
register_post_type( "article", $args );
I believe the part of code removing the prefix /custom-post-name/ from the urls is :
function gp_remove_cpt_slug( $post_link, $post, $leavename ) {
if ( 'article' != $post->post_type || 'publish' != $post->post_status ) {
return $post_link;
}
$post_link = str_replace( '/' . $post->post_type . '/', '/', $post_link );
return $post_link;
}
add_filter( 'post_type_link', 'gp_remove_cpt_slug', 10, 3 );
It has worked fine until now that I want to translate my website.
The translated articles get this url :
https://www.example.com/en/slug
The result is a 404 error
If I add (by hand) in the url the prefix custom-post-name that way :
https://www.example.com/en/custom-post-name/slug
Then it works.
What I need is to get completely rid of this prefix for my custom-post-type registered with the name "article". In the default language AND IN THE TRANSLATED versions made with the plugin Polylang
The complete code of my file wp-content/themes/mytheme/inc/custom-post-types.php is this :
<?php
function cptui_register_my_cpts_module() {
$labels = array(
"name" => __( "Modules", "" ),
"singular_name" => __( "Module", "" ),
);
$args = array(
"label" => __( "Modules", "" ),
"labels" => $labels,
"description" => "",
"public" => false,
"publicly_queryable" => false,
"show_ui" => true,
"show_in_rest" => false,
"rest_base" => "",
"has_archive" => false,
"show_in_menu" => true,
"exclude_from_search" => true,
"capability_type" => "page",
"map_meta_cap" => true,
"hierarchical" => false,
"rewrite" => array( "slug" => "module", "with_front" => true ),
"query_var" => true,
"menu_icon" => "dashicons-schedule",
"supports" => array( "title", "page-attributes" ),
);
register_post_type( "module", $args );
$labels = array(
"name" => __( "Articles", "" ),
"singular_name" => __( "Article", "" ),
);
$args = array(
"label" => __( "Articles", "" ),
"labels" => $labels,
"description" => "",
"public" => true,
"publicly_queryable" => true,
"show_ui" => true,
"show_in_rest" => false,
"rest_base" => "",
"has_archive" => false,
"show_in_menu" => true,
"exclude_from_search" => false,
"capability_type" => "page",
"map_meta_cap" => true,
"hierarchical" => false,
"rewrite" => array( "slug" => "article", "with_front" => true ),
"query_var" => true,
//"menu_icon" => "dashicons-schedule",
"menu_position" => 5,
"supports" => array( "title", "page-attributes", "comments", "editor" ),
"taxonomies" => array( "categorie" ),
);
register_post_type( "article", $args );
}
add_action( 'init', 'cptui_register_my_cpts_module' );
function cptui_register_my_taxes_categorie() {
/**
* Taxonomy: Catégories.
*/
$labels = array(
"name" => __( "Catégories", "" ),
"singular_name" => __( "Catégorie", "" ),
);
$args = array(
"label" => __( "Catégories", "" ),
"labels" => $labels,
"public" => true,
"hierarchical" => true,
"label" => "Catégories",
"show_ui" => true,
"show_in_menu" => true,
"show_in_nav_menus" => true,
"query_var" => true,
"rewrite" => array( 'slug' => 'categorie', 'with_front' => true, ),
"show_admin_column" => true,
"show_in_rest" => false,
"rest_base" => "",
"show_in_quick_edit" => true,
);
register_taxonomy( "categorie", array( "article" ), $args );
}
add_action( 'init', 'cptui_register_my_taxes_categorie' );
function gp_remove_cpt_slug( $post_link, $post, $leavename ) {
if ( 'article' != $post->post_type || 'publish' != $post->post_status ) {
return $post_link;
}
$post_link = str_replace( '/' . $post->post_type . '/', '/', $post_link );
return $post_link;
}
add_filter( 'post_type_link', 'gp_remove_cpt_slug', 10, 3 );
function gp_add_cpt_post_names_to_main_query( $query ) {
// Bail if this is not the main query.
if ( ! $query->is_main_query() ) {
return;
}
// Bail if this query doesn't match our very specific rewrite rule.
if ( ! isset( $query->query['page'] ) || 2 !== count( $query->query ) ) {
return;
}
// Bail if we're not querying based on the post name.
if ( empty( $query->query['name'] ) ) {
return;
}
// Add CPT to the list of post types WP will include when it queries based on the post name.
$query->set( 'post_type', array( 'post', 'page', 'article' ) );
}
add_action( 'pre_get_posts', 'gp_add_cpt_post_names_to_main_query' );
add_filter('request', 'rudr_change_term_request', 1, 1 );
function rudr_change_term_request($query){
$tax_name = 'categorie'; // specify you taxonomy name here, it can be also 'category' or 'post_tag'
// Request for child terms differs, we should make an additional check
if( $query['attachment'] ) :
$include_children = true;
$name = $query['attachment'];
else:
$include_children = false;
$name = $query['name'];
endif;
$term = get_term_by('slug', $name, $tax_name); // get the current term to make sure it exists
if (isset($name) && $term && !is_wp_error($term)): // check it here
if( $include_children ) {
unset($query['attachment']);
$parent = $term->parent;
while( $parent ) {
$parent_term = get_term( $parent, $tax_name);
$name = $parent_term->slug . '/' . $name;
$parent = $parent_term->parent;
}
} else {
unset($query['name']);
}
switch( $tax_name ):
/* case 'category':{
$query['category_name'] = $name; // for categories
break;
}
case 'post_tag':{
$query['tag'] = $name; // for post tags
break;
}*/
default:{
$query[$tax_name] = $name; // for another taxonomies
break;
}
endswitch;
endif;
return $query;
}
add_filter( 'term_link', 'rudr_term_permalink', 10, 3 );
function rudr_term_permalink( $url, $term, $taxonomy ){
$taxonomy_name = 'categorie'; // your taxonomy name here
$taxonomy_slug = 'categorie'; // the taxonomy slug can be different with the taxonomy name (like 'post_tag' and 'tag' )
// exit the function if taxonomy slug is not in URL
if ( strpos($url, $taxonomy_slug) === FALSE || $taxonomy != $taxonomy_name ) return $url;
$url = str_replace('/' . $taxonomy_slug, '', $url);
return $url;
}
?>
Thanks a lot for reading and any help,
François