public function test_validate_date_query_before_after() {
    // Valid values.
    $valid_args = array(
      array(
        'month' => 2,
        'year'  => 2014,
      ),
      array(
        'day'  => 8,
        'year' => 2014,
      ),
    );

    foreach ( $valid_args as $args ) {
      $this->assertTrue( $this->q->validate_date_values( array( 'before' => $args ) ) );
      $this->assertTrue( $this->q->validate_date_values( array( 'after' => $args ) ) );
    }

    // Invalid values.
    $invalid_args = array(
      array(
        'month' => 13,
      ),
      array(
        'day' => 32,
      ),
      array(
        'minute' => 60,
      ),
      array(
        'second' => 60,
      ),
      array(
        'week' => 54,
      ),
    );

    foreach ( $invalid_args as $args ) {
      $this->assertFalse( $this->q->validate_date_values( array( 'before' => $args ) ) );
      $this->assertFalse( $this->q->validate_date_values( array( 'after' => $args ) ) );
    }
  }