Ticket #39150: 39150.diff

src/wp-includes/rest-api/class-wp-rest-request.php

@@ -669 +669 @@
                         return true;
                 }
 
-                $params = json_decode( $this->get_body(), true );
+                // Allow an empty body. See https://core.trac.wordpress.org/ticket/39150.
+                $body = $this->get_body();
+                if ( empty( $body ) ) {
+                        return true;
+                }
+
+                $params = json_decode( $body, true );
 
                 /*
                  * Check for a parsing error.

tests/phpunit/tests/rest-api/rest-request.php

@@ -10 +10 @@
  * @group restapi
  */
 class Tests_REST_Request extends WP_UnitTestCase {
+
+        /** @var  WP_REST_Request */
+        public $request;
+
         public function setUp() {
                 parent::setUp();
 
@@ -414 +418 @@
                 $this->assertEquals( JSON_ERROR_SYNTAX, $data['json_error_code'] );
         }
 
+
+        public function test_has_valid_params_empty_json_no_error() {
+                if ( version_compare( PHP_VERSION, '5.3', '<' ) ) {
+                        return $this->markTestSkipped( 'JSON validation is only available for PHP 5.3+' );
+                }
+
+                $this->request->set_header( 'Content-Type', 'application/json' );
+                $this->request->set_body( '' );
+
+                $valid = $this->request->has_valid_params();
+                $this->assertNotWPError( $valid );
+        }
+
         public function test_has_multiple_invalid_params_validate_callback() {
                 $this->request->set_url_params( array(
                         'someinteger' => '123',