Can I configure the Elixir formatter to auto-sort my alias calls?

Questions / Help
#1

I often will get reminded by credo to sort my alias calls like below.

Is there a way I could configure the Elixir formatter (that is kicked by VS Code) to auto-sort these for me?

┃ [R] ↘ The alias `RetroTaxi.JoinBoard` is not alphabetically ordered among its group.
┃       lib/retro_taxi/board_creation.ex:12:9 #(RetroTaxi.BoardCreation)

It looks like formatter Plugins are a recent/upcoming (1.13) thing. Anyone ever try to do this?

https://hexdocs.pm/mix/master/Mix.Tasks.Format.html#module-plugins

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#2

I am also interested in the answer of this question.
Are there some examples how to do something like this?
Chrichton

#3

For now, formatter plugins only support sigils and custom file extensions. For what you want, you’d need to find a way to run code before or after the formatter, with Code.string_to_quoted_with_comments and Code.quoted_to_algebra + Inspect.Algebra.format. The challenge is in syncing the changes you did to the AST with the comments.

I created Sourceror specifically for this. Here is an example to sort dependencies in mix.exs:

source
|> Sourceror.parse_string!()
|> Macro.postwalk(fn
  {:defp, meta, [{:deps, _, _} = fun, body]} ->
    [{{_, _, [:do]}, block_ast}] = body
    {:__block__, block_meta, [deps]} = block_ast

    deps =
      Enum.sort_by(deps, fn {:__block__, _, [{{_, _, [name]}, _}]} ->
        Atom.to_string(name)
      end)

    {:defp, meta, [fun, [do: {:__block__, block_meta, [deps]}]]}

  quoted ->
    quoted
end)
|> Sourceror.to_string()
|> IO.puts()

You can do something similar to sort aliases.

Note: There is currently a bug affecting the ordering of comments under certain circumstances that I need to fix.

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