get_terms() does not recognize the 'slug' argument

[NemesisVex]

Description

When passing a slug to the get_terms() function, returned results are not filtered by that slug.

Steps to reproduce

1. In a theme template or plugin file, query for a known existing term in a taxonomy with get_terms(). For example: get_terms( [ 'taxonomy' => 'custom_tax_name', 'slug' => 'existing-slug'] );
2. Dump the contents of the get_terms query.

Expected outcome

Results show only those terms matching the slug.

Actual outcome

Results show all terms in the taxonomy.

[tnolte]

There we changes here 6 months ago that would be suspect. ​https://github.com/WordPress/wordpress-develop/blame/2bb5679d666474d024352fa53f07344affef7e69/src/wp-includes/class-wp-term-query.php#L554-L564

[peterwilsoncc]

@NemesisVex hello and welcome to trac!

I've attempted to reproduce this using WordPress 6.0.2 but without success. Are you able to check this running a default theme and without any plugins enabled?

This is a dump of running the command within wp-cli, each command returns the single term as expected:

wp> get_terms( [ 'taxonomy' => 'custom-taxo', 'slug' => 'term-1'] );
=> phar:///usr/local/src/wp-cli/bin/wp/vendor/wp-cli/shell-command/src/WP_CLI/Shell/REPL.php:52:
array(1) {
  [0] =>
  class WP_Term#2612 (10) {
    public $term_id =>
    int(9)
    public $name =>
    string(6) "Term 1"
    public $slug =>
    string(6) "term-1"
    public $term_group =>
    int(0)
    public $term_taxonomy_id =>
    int(9)
    public $taxonomy =>
    string(11) "custom-taxo"
    public $description =>
    string(0) ""
    public $parent =>
    int(0)
    public $count =>
    int(1)
    public $filter =>
    string(3) "raw"
  }
}


wp> get_terms( [ 'taxonomy' => 'custom-taxo', 'slug' => 'term-2'] );
=> phar:///usr/local/src/wp-cli/bin/wp/vendor/wp-cli/shell-command/src/WP_CLI/Shell/REPL.php:52:
array(1) {
  [0] =>
  class WP_Term#2614 (10) {
    public $term_id =>
    int(10)
    public $name =>
    string(6) "term 2"
    public $slug =>
    string(6) "term-2"
    public $term_group =>
    int(0)
    public $term_taxonomy_id =>
    int(10)
    public $taxonomy =>
    string(11) "custom-taxo"
    public $description =>
    string(0) ""
    public $parent =>
    int(0)
    public $count =>
    int(1)
    public $filter =>
    string(3) "raw"
  }
}

[NemesisVex]

I'm closing this ticket.

Upon further inspection of the client site that generated this bug report, the taxonomy being passed to the 'taxonomy' argument was being generated by a third party plugin. On this same client site, using a default taxonomy such as 'post_tag' or a properly registered taxonomy using register_taxonomy() does not result in the reported behavior.

I've already advised the client about the plugin in question.

Thank you!

[peterwilsoncc]

Thanks for the follow up, it's really appreciated.