Ticket #45265: 45265.4.diff

src/wp-includes/rest-api.php

@@ -17 +17 @@
 /**
  * Registers a REST API route.
  *
+ * Note: Do not use before the {@see 'rest_api_init'} hook.
+ *
  * @since 4.4.0
+ * @since 5.1.0 Added a _doing_it_wrong() notice when not called on or after the rest_api_init hook.
  *
  * @param string $namespace The first URL segment after core prefix. Should be unique to your package/plugin.
  * @param string $route     The base URL for route you are adding.
@@ -41 +44 @@
                 return false;
         }
 
+        if ( ! did_action( 'rest_api_init' ) ) {
+                _doing_it_wrong( 'register_rest_route', __( 'REST API routes must be registered on the rest_api_init action.' ), '5.1.0' );
+        }
+
         if ( isset( $args['args'] ) ) {
                 $common_args = $args['args'];
                 unset( $args['args'] );

tests/phpunit/tests/rest-api.php

@@ -14 +14 @@
  */
 class Tests_REST_API extends WP_UnitTestCase {
         public function setUp() {
+                parent::setUp();
+
                 // Override the normal server with our spying server.
                 $GLOBALS['wp_rest_server'] = new Spy_REST_Server();
-                parent::setUp();
+                do_action( 'rest_api_init' );
         }
 
         public function tearDown() {