Elixir representer normalizations

The Elixir representer applies a number of normalizations. Please refer to the code or the test data for details.

Remove comments and docs

All comments, docs, moduledocs and typedocs are removed.

Before

defmodule Fake do
  @moduledoc """
  Fake module to demonstrate stuff
  """

  @doc "Not much to see here"
  def foo do
    # TODO: return bar
    nil
  end
end

After

defmodule Fake do
  def foo do
    nil
  end
end

Sort imports order

The import statements at the top of the modules or functions are ordered as: alias, use, require, import.

Before

defmodule Fake do
  import D
  alias A.U.V
  use B
  alias A.{T, S}
  require C

  def foo do
    import Z
    alias X
    use Y
  end

  import NotTouched
  alias NotTouched
end

After

defmodule Fake do
  alias A.{S, T}
  alias A.U.V
  use B
  require C
  import D

  def foo do
    alias X
    use Y
    import Z
  end

  import NotTouched
  alias NotTouched
end

Format code

The code is formatted using [mix code][mix-code], forcing do end blocks. All functions in pipes are written with parentheses. Types are written without.

Before

[]: # (elixir-formatter-disable-next-block)

defmodule    Fake   do
        @type foo() :: integer() | atom
def foo, do:    nil |> bar
end

After

defmodule Fake do
  @type foo() :: integer | atom
  def foo do
    nil |> bar()
  end
end

Normalize identifiers

Identifiers are normalized to a placeholder value. Some special variables and module attributes (_, @spec, __MODULE__, etc.) are not replaced. Keys from maps, structs and keyword lists are not normalized.

Before

defmodule Fake do
  alias Fake, as: SuperFake
  @my_constant 42

  @impl true
  def foo(bar) when is_integer(bar) do
    bar + @my_constant
  end

  def foo(%{a: a} = bar) do
    %{bar | a: a + @my_constant}
  end

  def foo(_), do: nil
end

After

defmodule Placeholder_1 do
  alias Placeholder_1, as: Placeholder_2
  @placeholder_6 42
  @impl true
  def placeholder_4(placeholder_5) when is_integer(placeholder_5) do
    placeholder_5 + @placeholder_6
  end

  def placeholder_4(%{a: placeholder_7} = placeholder_5) do
    %{placeholder_5 | a: placeholder_7 + @placeholder_6}
  end

  def placeholder_4(_) do
    nil
  end
end

Sort keys in maps and structs

Keys in maps and structs are sorted. Keys in keyword lists are not sorted.

Before

defmodule Fake do
  def foo do
    %MyStruct{z: 3, y: 2, x: 1}
    m = %{c: 3, a: 1, b: 2}
    %{m | b: 20, a: 10}
    [b: 2, a: 1]
  end
end

After

defmodule Fake do
  def foo do
    %MyStruct{x: 1, y: 2, z: 3}
    placeholder_3 = %{a: 1, b: 2, c: 3}
    %{placeholder_3 | a: 10, b: 20}
    [b: 2, a: 1]
  end
end