Ticket #18548: 18548.4.diff

src/wp-includes/default-filters.php

@@ -196 +196 @@
 add_filter( 'http_request_host_is_external', 'allowed_http_request_hosts', 10, 2 );
 
 // Actions
+add_action( 'wp_head',             '_wp_render_title_tag',            1     );
 add_action( 'wp_head',             'wp_enqueue_scripts',              1     );
 add_action( 'wp_head',             'feed_links',                      2     );
 add_action( 'wp_head',             'feed_links_extra',                3     );

src/wp-includes/general-template.php

@@ -731 +731 @@
 }
 
 /**
+ * Display <title> tag with contents.
+ *
+ * @since 4.1.0
+ * @access private
+ */
+function _wp_render_title_tag() {
+        if ( ! current_theme_supports( 'title-tag' ) ) {
+                return;
+        }
+
+        // This can only work internally on wp_head.
+        if ( ! did_action( 'wp_head' ) && ( ! function_exists( 'doing_action' ) || ! doing_action( 'wp_head' ) ) ) {
+                return;
+        }
+
+        echo "<title>" . wp_title( '|', false, 'right' ) . "</title>\n";
+}
+
+/**
  * Display or retrieve page title for all areas of blog.
  *
  * By default, the page title will display the separator before the page title,

src/wp-includes/theme.php

@@ -1607 +1607 @@
                                 define( 'BACKGROUND_IMAGE', $args[0]['default-image'] );
 
                         break;
+
+                // Ensure that 'title-tag' is accessible in the admin.
+                case 'title-tag' :
+                        if ( function_exists( 'doing_action' )
+                           && ! doing_action( 'after_setup_theme' ) // can be called here
+                           && ! doing_action( 'init' ) // can also be called here
+                           && ( doing_action() || did_action( 'wp_loaded' ) ) // can be called in functions.php but must happen before wp_loaded, i.e. not in header.php
+                        ) {
+                                _doing_it_wrong( "add_theme_support( 'title-tag' )", __( "You need to add support before 'wp_loaded'." ), '4.1.0' );
+                        }
+                        break;
         }
 
         $_wp_theme_features[ $feature ] = $args;
@@ -1759 +1770 @@
         if ( !isset( $_wp_theme_features[$feature] ) )
                 return false;
 
+        if ( 'title-tag' == $feature ) {
+                // Don't confirm support unless called internally.
+                $trace = debug_backtrace();
+                if ( '_wp_render_title_tag' !== $trace[1]['function'] ) {
+                        return false;
+                }
+        }
+
         // If no args passed then no extra checks need be performed
         if ( func_num_args() <= 1 )
                 return true;