Extending mix format rules?

A few things that annoy me with the opinionated formatter (when the line_length is exceeded) are

<<0,1,2,3,..>> Binary gets expanded to

<<
0,
1,
2,
3,
..
>>

Extra indent

values = [{0, "a"}, {1, "c"}, {2, "e"}]


value = values 
|> Enum.find_value(fn{key, letter}-> key == 1 && letter end)
|> String.upcase()
|> Base.encode64()

# Formatted

value = 
  values
  |> Enum.find_value(fn {key, letter} -> key == 1 && letter end)
  |> String.upcase()
  |> Base.encode64()

I feel without the extra indent its clearer to read if the function has more scopes.

and / or get placed at end of line

    Enum.filter(values, fn{k,v}->
      k == 5
      and k != 7
      and v != "a"
    end)


    Enum.filter(values, fn {k, v} ->
      k == 5 and
        k != 7 and
        v != "a"
    end)

Reading from left to right makes it take longer to comprehend. If you read right to left its natural tho.

If line gets expanded in a cond

  Enum.filter(values, fn {k, v} ->
      cond do
        k == 5 and k == 5 and k == 5 and k == 5 and k == 5 and k == 5 and k == 5 and k == 5 -> false
        k != 7 -> false
        v != "a" -> false
        true -> true
      end
    end)

    Enum.filter(values, fn {k, v} ->
      cond do
        k == 5 and k == 5 and k == 5 and k == 5 and k == 5 and k == 5 and k == 5 and k == 5 ->
          false

        k != 7 ->
          false

        v != "a" ->
          false

        true ->
          true
      end
    end)

Extra spaces even tho the lines are short, the results are placed on seperate lines.

Does anyone have any idea how to slightly tune the formatter? I know its meant to be opinionated and the official answer will be, if you dont like it dont use it.

Hi,

The formatter is not configurable besides the line length and the optional parentheses on some function calls.

I also dislike some of the things the formatter does, but I dislike the time and energy spent arguing about formatting even more, so I live with it.

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