Taxonomy: Introduce the is_term_publicly_viewable() function.

This is the taxonomy term counterpart to the `is_post_publicly_viewable()` function. Although the logic for terms is more straight forward this serves the same purpose as introducing the corresponding function for posts -- to centralise and reduce the logic needed to validate a term and determine if it's publicly viewable.

Props peterwilsoncc, costdev, johnbillion

Fixes #56215


git-svn-id: https://develop.svn.wordpress.org/trunk@53893 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/admin-bar.php

@@ -809,7 +809,7 @@ function wp_admin_bar_edit_menu( $wp_admin_bar ) {
 			);
 		} elseif ( 'term' === $current_screen->base && isset( $tag ) && is_object( $tag ) && ! is_wp_error( $tag ) ) {
 			$tax = get_taxonomy( $tag->taxonomy );
-			if ( is_taxonomy_viewable( $tax ) ) {
+			if ( is_term_publicly_viewable( $tag ) ) {
 				$wp_admin_bar->add_node(
 					array(
 						'id'    => 'view',

src/wp-includes/taxonomy.php

@@ -4992,6 +4992,26 @@ function is_taxonomy_viewable( $taxonomy ) {
 	return $taxonomy->publicly_queryable;
 }
 
+/**
+ * Determines whether a term is publicly viewable.
+ *
+ * A term is considered publicly viewable if its taxonomy is viewable.
+ *
+ * @since 6.1.0
+ *
+ * @param int|WP_Term $term Term ID or term object.
+ * @return bool Whether the term is publicly viewable.
+ */
+function is_term_publicly_viewable( $term ) {
+	$term = get_term( $term );
+
+	if ( ! $term ) {
+		return false;
+	}
+
+	return is_taxonomy_viewable( $term->taxonomy );
+}
+
 /**
  * Sets the last changed time for the 'terms' cache group.
  *