module FakeRedis::GeoCommands

def geodist(key, member1, member2, unit = "m")
  unit = unit.to_s
  raise_command_error("ERR unsupported unit provided. please use #{DISTANCE_UNITS.keys.join(', ')}") unless DISTANCE_UNITS.include?(unit)
  set = (data[key] || GeoSet.new)
  point1 = set.get(member1)
  point2 = set.get(member2)
  if point1 && point2
    distance = point1.distance_to(point2)
    distance_in_units = distance / DISTANCE_UNITS[unit]
    distance_in_units.round(REDIS_DOUBLE_PRECISION).to_s
  end
end