Taxonomy: Introduce `is_taxonomy_viewable()`.

This utility function allows for easy detection whether terms for a taxonomy are considered publicly viewable.

Props andizer.
Fixes #44466.

Built from https://develop.svn.wordpress.org/trunk@43386


git-svn-id: http://core.svn.wordpress.org/trunk@43214 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-admin/includes/class-wp-terms-list-table.php

@@ -470,7 +470,7 @@ class WP_Terms_List_Table extends WP_List_Table {
 				__( 'Delete' )
 			);
 		}
-		if ( $tax->public ) {
+		if ( is_taxonomy_viewable( $tax ) ) {
 			$actions['view'] = sprintf(
 				'<a href="%s" aria-label="%s">%s</a>',
 				get_term_link( $tag ),

wp-includes/admin-bar.php

@@ -728,7 +728,7 @@ 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 ) )
-			&& $tax->public ) {
+			&& is_taxonomy_viewable( $tax ) ) {
 			$wp_admin_bar->add_menu(
 				array(
 					'id'    => 'view',

wp-includes/taxonomy.php

@@ -4548,3 +4548,22 @@ function wp_check_term_hierarchy_for_loops( $parent, $term_id, $taxonomy ) {
 
 	return $parent;
 }
+
+/**
+ * Determines whether a taxonomy is considered "viewable".
+ *
+ * @since 5.0.0
+ *
+ * @param string|WP_Taxonomy $taxonomy Taxonomy name or object.
+ * @return bool Whether the taxonomy should be considered viewable.
+ */
+function is_taxonomy_viewable( $taxonomy ) {
+	if ( is_scalar( $taxonomy ) ) {
+		$taxonomy = get_taxonomy( $taxonomy );
+		if ( ! $taxonomy ) {
+			return false;
+		}
+	}
+
+	return $taxonomy->publicly_queryable;
+}

wp-includes/version.php

@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.0-alpha-43385';
+$wp_version = '5.0-alpha-43386';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.