WPML 4.7 Conflict with Plugins Using PSR/Log 3.0 Causes Fatal Error in WP-CLI

Overview of the issue

WPML 4.7 has a compatibility issue with plugins that use PSR/Log 3.0, such as Rollbar. When WPML and Rollbar are both active, running WP-CLI commands (e.g., wp --info) triggers a fatal error due to method signature mismatches in the DebugFileLogger class.

PHP Fatal error:  Declaration of WPML\\PHP\\Logger\\DebugFileLogger::log($level, $message, array $context = []) must be compatible with Psr\\Log\\AbstractLogger::log($level, Stringable|string $message, array $context = []): void in ...\\wp-content\\plugins\\sitepress-multilingual-cms\\vendor\\wpml\\wpml\\lib\\Php\\Logger\\DebugFileLogger.php on line 8

Workaround

Please, make sure of having a full site backup of your site before proceeding.

• Open …/wp-content/plugins/sitepress-multilingual-cms/vendor/wpml/wpml/lib/Php/Logger/DebugFileLogger.php file.
• Replace:

  namespace WPML\PHP\Logger;
  
  class DebugFileLogger extends \Psr\Log\AbstractLogger {
  
  
    public function log( $level, $message, array $context = array() ) {
      if ( ! defined( 'WP_DEBUG' ) || ! WP_DEBUG ) {
        return;
      }
  
      $log = date( 'Y-m-d H:i:s' ) . ' [' . $level . '] ' . $message . PHP_EOL;
      \error_log( $log );
    }
  
  
  }
  

• With:

  namespace WPML\PHP\Logger;
  
  use Psr\Log\AbstractLogger;
  use Stringable;
  
  class DebugFileLogger extends AbstractLogger {
  
    public function log($level, $message, array $context = []): void {
      if ( ! defined( 'WP_DEBUG' ) || ! WP_DEBUG ) {
        return;
      }
  
      $log = date( 'Y-m-d H:i:s' ) . ' [' . $level . '] ' . (string) $message . PHP_EOL;
      \error_log( $log );
    }
  
  }