Fl4m3Ph03n1x
I have a module that uses TypedStruct to create structs. This is the code:
defmodule Shared.Data.Authorization do
@moduledoc """
Saves authorization details for a user. It also contains other details.
"""
use TypedStruct
alias Shared.Utils.Structs
@type authorization :: %{
(cookie :: String.t()) => String.t(),
(token :: String.t()) => String.t()
}
@derive Jason.Encoder
typedstruct enforce: true do
@typedoc "Authorization information for a user"
field(:cookie, String.t())
field(:token, String.t())
end
@spec new(authorization()) :: __MODULE__.t()
def new(%{"cookie" => cookie, "token" => token} = auth)
when is_binary(cookie) and is_binary(token) do
Structs.string_map_to_struct(auth, __MODULE__)
end
end
The problem here is that Gradient does not seem to understand that t() is created, so it errors out:
lib/data/authorization.ex: The function call on line 26 is expected to have type t() but it has type struct()
24 def new(%{“cookie” => cookie, “token” => token} = auth)
25 when is_binary(cookie) and is_binary(token) do
26 Structs.string_map_to_struct(auth, MODULE)
27 end
For additional context, here is the string_map_to_struct code:
@spec string_map_to_struct(map, module | struct) :: struct
def string_map_to_struct(data, target_struct) do
data
|> Morphix.atomorphiform!() # string_map to atom_map
|> data_to_struct(target_struct)
end
@spec data_to_struct(Enumerable.t(), module | struct) :: struct
def data_to_struct(data, target_struct), do: struct(target_struct, data)
I decided to convert that code into its native form using defstruct:
defmodule Shared.Data.Authorization do
@moduledoc """
Saves authorization details for a user. It also contains other details.
"""
alias Shared.Utils.Structs
@enforce_keys [:cookie, :token]
defstruct [:cookie, :token]
@type authorization :: %{
(cookie :: String.t()) => String.t(),
(token :: String.t()) => String.t()
}
@typedoc "Authorization information for a user"
@type t() :: %__MODULE__{
cookie: String.t(),
token: String.t()
}
@spec new(authorization()) :: t()
def new(%{"cookie" => cookie, "token" => token} = auth)
when is_binary(cookie) and is_binary(token) do
Structs.string_map_to_struct(auth, __MODULE__)
end
end
Gradient does not complain here.
Is there a fix for this?
(other than removing typed struct?)
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