There is a limit to the number of nested shortcode attributes, and you may have reached that limit. I would try it like this first:
[wpv-conditional if="( is_tax('niveau', null) eq '1' )"]
[wpv-view name="infos-sur-cet-etablissement" etablissement="[wpv-view name='liste-des-etablissements-avec-des-formations-par-niveau' wpvniveau='[wpv-taxonomy-archive info='slug']']"]
[/wpv-conditional]
I would also try it like this:
[wpv-conditional if="( is_tax('niveau', null) eq '1' )"]
[wpv-view name="infos-sur-cet-etablissement" etablissement="[wpv-view name='liste-des-etablissements-avec-des-formations-par-niveau' wpvniveau='[wpv-taxonomy-archive info="slug"]']"]
[/wpv-conditional]
If neither of these works correctly, you know that you have exceeded the limit for nesting shortcode attributes. One thing I know you could do is use the is_tax conditional to check for each specific term in the taxonomy, then hard-code that term in the shortcode attribute like so:
[wpv-conditional if="( is_tax( 'type', array( 'formation-initiale' ) ) eq '1' )"]
[wpv-view name="liste-des-etablissements-avec-des-formations-par-type" wpvtypedeformation="formation-initiale"]
[/wpv-conditional]
https://developer.wordpress.org/themes/basics/conditional-tags/#a-taxonomy-page
This is not really practical if you have many terms, because you will have many conditionals. You will have to update the code manually any time a new term is added, so that is not really practical either. To fix this, you could use a custom shortcode that returns the current archive term slug without using any shortcode attributes. I have one from another ticket, with a few modifications:
// https://toolset.com/forums/topic/display-list-of-parent-posts
function tssupp_get_current_archive_term_slug( $atts ){
$taxObj = get_queried_object();
$tax = isset($taxObj->taxonomy) ? $taxObj->taxonomy : 0;
$slug = isset($taxObj->slug) ? $taxObj->slug : '';
return $slug;
}
add_shortcode( 'tssupp-get-current-archive-term-slug', 'tssupp_get_current_archive_term_slug' );
Add that code to functions.php or a new custom code snippet , then register tssupp-get-current-archive-term-slug in Toolset > Settings > Front-end Content > 3rd party shortcode attributes. Then you can use it like this:
[wpv-conditional if="( is_tax('niveau', null) eq '1' )"]
[wpv-view name="infos-sur-cet-etablissement" etablissement="[wpv-view name='liste-des-etablissements-avec-des-formations-par-niveau' wpvniveau='[tssupp-get-current-archive-term-slug]']"]
[/wpv-conditional]
This will fix the problem with maximum nesting level for shortcode attributes.