Extend the term context to allow adding a field to any child terms only

[renatonascalves]

Description

Ideally, Fieldmanager_Context_Term could be extended so that a field using this context can be added to child terms only (or maybe only to parent terms too).

Currently, one can set a specific parent term id:

wordpress-fieldmanager/php/context/class-fieldmanager-context-term.php

Lines 42 to 47 in 584979f

	/**
	* Only show this field on child terms of this parent.
	*
	* @var int
	*/
	public $parent = '';

Use Case

Here is a real use case where this was needed and could be used:

$fm = new Fieldmanager_Checkbox(
	[
		'checked_value' => '1',
		'name'          => 'field_key',
	]
);

$fm->add_term_meta_box(
	title: __( 'Enable in Child Term Only' ),
	taxonomies: [ 'category', 'post_tag' ],
	show_on_add: false,
	parent: 254546546 // This only works if one sets the parent term ID.
);

[mboynes]

Do you think that this is a necessary change for FM to make, or is it something that could easily be accomplished outside of FM? For instance...

$term = get_queried_object();
if ( $term instanceof \WP_Term && $term->parent ) {
    // FM definitions...
}

[renatonascalves]

Do you think that this is a necessary change for FM to make

I thought about suggesting this into the core plugin because it already offers a similar option with the parent. But it is not required to be.

Meaning that my suggestion was less about making it work for the use case and more about suggesting it is baked in.