defstruct sets @enforce_keys to nil

[lud]

Elixir and Erlang/OTP versions

Erlang/OTP 25 [erts-13.0.4] [source] [64-bit] [smp:16:16] [ds:16:16:10] [async-threads:1] [jit:ns]

Elixir 1.14.0 (compiled with Erlang/OTP 25)

Operating system

xUbuntu 21.04

Current behavior

The new/1 function will fail because @enforce_keys is nil.

defmodule X do
  @enforce_keys [:a, :b, :c]
  IO.inspect(@enforce_keys, label: "@enforce_keys before")
  defstruct @enforce_keys
  IO.inspect(@enforce_keys, label: "@enforce_keys after ")

  def new(vars) do
    case Keyword.drop(vars, @enforce_keys) do
      [] -> struct!(__MODULE__, vars)
      list -> SomeModule.raise_unknown_opts(vars)
    end
  end
end

X.new(x: 1)

** (FunctionClauseError) no function clause matching in Keyword.drop/2    
    
    The following arguments were given to Keyword.drop/2:
    
        # 1
        [x: 1]
    
        # 2
        nil
    
    Attempted function clauses (showing 1 out of 1):
    
        def drop(keywords, keys) when is_list(keywords) and is_list(keys)

Expected behavior

It worked as expected with the following versions

elixir 1.13.4-otp-25
erlang 25.0

[lud]

🏎️