best way to mock a global static method

my application has a logger library with the signature:

final class Logger {
  public static method debug($msg);
  public static method warn($msg);
  public static method error($msg);
}

the class i want to test, another global static helper, use it as

final class TestMe {
  public static method TestThis(){
    Logger::debug('TestThis() called');
    doThings();
  }
}

How to test the TestMe class by mocking the Logger one and waiting for the expected messages?