class PostHog::FieldParser

def parse_for_alias(fields)
  common = parse_common_fields(fields)
  distinct_id = common[:distinct_id] # must both be set and move to properties
  alias_field = fields[:alias]
  check_presence! alias_field, 'alias'
  common.merge(
    {
      type: 'alias',
      event: '$create_alias',
      distinct_id: distinct_id,
      properties:
        { distinct_id: distinct_id, alias: alias_field }.merge(
          common[:properties] || {}
        )
    }
  )
end