Ticket #21881: 21881.3.patch

src/wp-includes/category-template.php

@@ -511 +511 @@
                 }
         } else {
                 if ( ! empty( $show_option_all ) ) {
-                        $posts_page = ( 'page' == get_option( 'show_on_front' ) && get_option( 'page_for_posts' ) ) ? get_permalink( get_option( 'page_for_posts' ) ) : home_url( '/' );
+
+                        /*
+                         * If the taxonomy is exclusive to one post type (not posts/pages) *and* an archive for that post type exists,
+                         * link to the post type archive instead of home
+                         */
+                        $taxonomy_object = get_taxonomy( $r['taxonomy'] );
+                        $link_to_post_type_archive = false;
+                        if ( 1 === count( $taxonomy_object->object_type ) && ! in_array( $taxonomy_object->object_type['0'], array( 'post', 'page' ) ) ) {
+                                $tax_post_type = get_post_type_object( $taxonomy_object->object_type['0'] );
+                                $link_to_post_type_archive = (bool) $tax_post_type->has_archive;
+                        }
+
+                        if ( $link_to_post_type_archive ) {
+                                $posts_page = get_post_type_archive_link( $taxonomy_object->object_type['0'] );
+                        } elseif ( 'page' == get_option( 'show_on_front' ) && get_option( 'page_for_posts' ) ) {
+                                $posts_page = get_permalink( get_option( 'page_for_posts' ) );
+                        } else {
+                                $posts_page = home_url( '/' );
+                        }
                         $posts_page = esc_url( $posts_page );
                         if ( 'list' == $r['style'] ) {
                                 $output .= "<li class='cat-item-all'><a href='$posts_page'>$show_option_all</a></li>";