Ecto.New broken after recent update

Questions / Help
,
1

I recently updated Ecto along with some other packages and noticed some function changes. They added Repo.transact\2, so I could remove my helper function which I found on these forums a while back. Nice :slight_smile:

But some other code was now showing warnings - anything starting with Ecto.Multi.new

Here’s the shortened warning:

The call 'Elixir.Ecto.Multi':update
         (#{'__struct__' := 'Elixir.Ecto.Multi',
            'names' := #{'__struct__' := 'Elixir.MapSet', 'map' := #{}},
            'operations' := []},
          'user',
          _changeset@1 ::
            ...,
                'validations' := [{atom(), _}]}) does not have a term of type 
          #{'__struct__' := 'Elixir.Ecto.Multi',
            'names' :=
                #{'__struct__' := 'Elixir.MapSet',
                  'map' := 'Elixir.MapSet':internal(_)},
            'operations' := [{_, {_, _} | {_, _, _} | {_, _, _, _}}]} (with opaque subterms) as 1st argument

Here’s the code:

Ecto.Multi.new()
    |> Ecto.Multi.update(:user, changeset)
    |> Ecto.Multi.delete_all(:tokens, UserToken.user_and_contexts_query(user, :all))
    |> Repo.transact()
    |> case do
      {:ok, %{user: user}} -> {:ok, user}
      {:error, :user, changeset, _} -> {:error, changeset}
    end

It pops up in 6 other places, also with complaints about insert_all.

So I’m sure the problem is with Multi.new but the changelog never mentions it.

Any idea what is going on here?

1 Like
2

I wonder if it’s somehow related to the MapSet default used in Ecto.Multi.new being in the struct definition:

Does the Dialyzer error change if you replace Ecto.Multi.new with an explicit initialization?

%Ecto.Multi{names: MapSet.new(), operations: []}
    |> Ecto.Multi.update(:user, changeset)
    |> Ecto.Multi.delete_all(:tokens, UserToken.user_and_contexts_query(user, :all))
...
3

I suspect so—per the warning

#{
  '__struct__' := 'Elixir.Ecto.Multi',
  'names' := #{
    '__struct__' := 'Elixir.MapSet',
-    'map' := #{}
+    'map' := 'Elixir.MapSet':internal(_)}
  },
  'operations' := []
}

The :map field of the MapSet struct was made @opaque in Elixir 3 years ago:

I’m guessing somebody’s code or typespec (possibly yours or Ecto’s) is relying on the internal fields of the MapSet struct, including expecting the now-opaque :map field to be a map. (MapSet uses :sets under the hood, whose typing is also opaque, so there’s not much to do here except not rely on such fields.)

4

Unfortunately the warning is still there after this change.

5

Some of the functions where generated with the default Phoenix gen.auth but I started this project with This book, so sure they are probably old now :smiley: but I have other parts which are more recent with the same problem.

That said, I cleaned and recompiled all deps so I don’t think its from old code anymore. These were the only changes in the mix file… unless Dialyzer updated and I forgot?

  {:ecto_sql, "~> 3.12.1"} -> {:ecto_sql, "~> 3.13.2"},
  {:floki, ">= 0.37.1", only: :test} -> {:floki, ">= 0.38.0", only: :test},
  {:phoenix_ecto, "~> 4.6.4"} -> {:phoenix_ecto, "~> 4.6.5"},
  {:req, "~> 0.5.10"} -> {:req, "~> 0.5.12"},
  {:swoosh, "~> 1.19.1"} -> {:swoosh, "~> 1.19.3"},
  {:timex, "~> 3.7.11"} -> {:timex, "~> 3.7.13"}