List classes that extend the current class on the Code Reference

[grapplerulrich]

Migrated from an ​issue filed on the phpdoc-parser repo on GitHub:

List child classes as "Used by" in the parent class

I was interested which classes extend the Walker class.

[DrewAPicture]

Interesting idea. This would be a great feature to implement on the Code Reference. The nice thing is that the parser already stores the parent classes in meta during parsing ('extends'), so it would be a simple query to retrieve that list. And with the auto-linking of known classes, we wouldn't even have to handle that part, just get the list and output it.

Related: #1847, #174

[coffee2code]

In 3809:

developer.wordpress.org: For wp-parser-class, list parent class under 'Uses' and list extending classes under 'Used By'.

• Change post_type_has_uses_info() and post_type_has_usage_info() to return true for 'wp-parser-class' post type.
• In template-related.php, check that $uses has a value before using it.
• In get_uses() and get_used_by()`, find classes related via the custom field '_wp-parser_extends', which notes the class being extended.

Fixes #1855.

[grapplerulrich]

Thanks!