API: Ignore '_' parameter in jsonp callback mode

jQuery has a misfeature where it by default appends a '_' parameter as a
cachebuster in jsonp mode. So, when in jsonp mode, mark this bogus
parameter as used to avoid an unnecessary warning.

Bug: T94015
Change-Id: I43373439a3605e4589315139c30976c6c2f68542

1 files changed, 9 insertions, 0 deletions

diff --git a/includes/api/ApiFormatJson.php b/includes/api/ApiFormatJson.php
index 43877b784b98..9538842466e9 100644
--- a/includes/api/ApiFormatJson.php
+++ b/includes/api/ApiFormatJson.php
@@ -35,6 +35,15 @@ class ApiFormatJson extends ApiFormatBase {
 	public function __construct( ApiMain $main, $format ) {
 		parent::__construct( $main, $format );
 		$this->isRaw = ( $format === 'rawfm' );
+
+		if ( $this->getMain()->getCheck( 'callback' ) ) {
+			# T94015: jQuery appends a useless '_' parameter in jsonp mode.
+			# Mark the parameter as used in that case to avoid a warning that's
+			# outside the control of the end user.
+			# (and do it here because ApiMain::reportUnusedParams() gets called
+			# before our ::execute())
+			$this->getMain()->getCheck( '_' );
+		}
 	}
 
 	public function getMimeType() {