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JobQueue::push

	final public function push( $jobs, $flags = 0 ) {
		$this->batchPush( is_array( $jobs ) ? $jobs : array( $jobs ), $flags );
	}

JobQueueGroup::push

		$ok = true;
		foreach ( $jobsByType as $type => $jobs ) {
			if ( $this->get( $type )->push( $jobs ) ) {
				JobQueueAggregator::singleton()->notifyQueueNonEmpty( $this->wiki, $type );
			} else {
				$ok = false;
			}
		}

So $ok is always going to become false