WPDBTrait: add support for nullsafe object operator

... for method calls.

Tested via the `PreparedSQL` sniff.

WordPress/Helpers/WPDBTrait.php

@@ -13,6 +13,7 @@
 use PHP_CodeSniffer\Util\Tokens;
 use PHPCSUtils\BackCompat\BCFile;
 use PHPCSUtils\Tokens\Collections;
+use PHPCSUtils\Utils\Operators;
 
 /**
  * Helper utilities for sniffs which examine WPDB method calls.
@@ -68,12 +69,25 @@ protected function is_wpdb_method_call( File $phpcsFile, $stackPtr, $target_meth
 			null,
 			true
 		);
-		if ( false === $is_object_call
-			|| isset( Collections::objectOperators()[ $tokens[ $is_object_call ]['code'] ] ) === false
-		) {
+
+		if ( false === $is_object_call ) {
 			return false;
 		}
 
+		if ( isset( Collections::objectOperators()[ $tokens[ $is_object_call ]['code'] ] ) === false ) {
+			// Allow for when the nullsafe object operator has not been backfilled yet.
+			if ( \T_INLINE_THEN !== $tokens[ $is_object_call ]['code']
+				|| Operators::isNullsafeObjectOperator( $phpcsFile, $is_object_call ) === false
+			) {
+				return false;
+			}
+
+			if ( \T_INLINE_THEN === $tokens[ $is_object_call ]['code'] ) {
+				// Non-backfilled nullsafe object operator. Move the stackPtr one forward to the ->.
+				++$is_object_call;
+			}
+		}
+
 		$methodPtr = $phpcsFile->findNext( Tokens::$emptyTokens, ( $is_object_call + 1 ), null, true, null, true );
 		if ( false === $methodPtr ) {
 			return false;

WordPress/Tests/DB/PreparedSQLUnitTest.inc

@@ -108,5 +108,8 @@ $wpdb
 WPDB::prepare( "SELECT * FROM $wpdb->posts WHERE post_title LIKE '" . foo() . "';" ); // Bad.
 $wpdb->Query( "SELECT * FROM $wpdb->posts WHERE post_title LIKE '" . foo() . "';" ); // Bad.
 
+$wpdb?->query( "SELECT * FROM $wpdb->posts WHERE post_title LIKE '" . (int) $foo . "';" ); // OK.
+$wpdb?->query( "SELECT * FROM $wpdb->posts WHERE post_title LIKE '" . foo() . "';" ); // Bad.
+
 // Don't throw an error during live coding.
 wpdb::prepare( "SELECT * FROM $wpdb->posts

WordPress/Tests/DB/PreparedSQLUnitTest.php

@@ -51,6 +51,7 @@ public function getErrorList() {
 			106 => 1,
 			108 => 1,
 			109 => 1,
+			112 => 1,
 		);
 	}