sort |> reverse => sort(:desc)

Author: novaugust

CHANGELOG.md

@@ -7,6 +7,9 @@ they can and will change without that change being reflected in Styler's semanti
 
 ### Improvements
 
+- `enum |> Enum.sort() |> Enum.reverse()` => `Enum.sort(enum, :desc)`
+- Req pipe optimizations (see below!)
+
 #### Req pipe optimizations
 
 [Req](https://github.com/wojtekmach/req) is a popular HTTP Client. If you aren't using it, you can just ignore this whole section!

docs/pipes.md

@@ -110,6 +110,10 @@ a |> Enum.filter(fun) |> List.first(default) |> ...
 # Styled:
 a |> Enum.find(fun) |> ...
 a |> Enum.find(default, fun) |> ...
+
+# Given:
+a |> Enum.sort() |> Enum.reverse() |> ...
+a |> Enum.sort(:desc) |> ...
 ```
 
 ## Unpiping Single Pipes

lib/style/pipes.ex

@@ -294,6 +294,22 @@ defmodule Styler.Style.Pipes do
   defp fix_pipe({:|>, m, [lhs, {{:., m2, [{anon_fun, _, _}] = fun}, _, []}]}) when anon_fun in [:&, :fn],
     do: {:|>, m, [lhs, {:then, m2, fun}]}
 
+  # `lhs |> Enum.sort([:asc, :desc]) |> Enum.reverse()` => `lhs |> Enum.sort(:desc | :asc)`
+  defp fix_pipe(
+         pipe_chain(
+           pm,
+           lhs,
+           {{:., _, [{_, _, [:Enum]}, :sort]} = sort, meta, sort_args},
+           {{:., _, [{_, _, [:Enum]}, :reverse]}, _, []}
+         ) = node
+       ) do
+     case sort_args do
+       [] -> {:|>, pm, [lhs, {sort, meta, [{:__block__, [line: meta[:line]], [:desc]}]}]}
+       [{_, m, [:desc]}] -> {:|>, pm, [lhs, {sort, meta, [{:__block__, m, [:asc]}]}]}
+       [{_, m, [:asc]}] -> {:|>, pm, [lhs, {sort, meta, [{:__block__, m, [:desc]}]}]}
+       _ -> node
+     end
+  end
   # `lhs |> Enum.reverse() |> Enum.concat(enum)` => `lhs |> Enum.reverse(enum)`
   defp fix_pipe(
          pipe_chain(

test/style/pipes_test.exs

@@ -576,6 +576,13 @@ defmodule Styler.Style.PipesTest do
       )
     end
 
+    test "Enum.sort/Enum.reverse" do
+      assert_style("a |> Enum.sort(direction) |> Enum.reverse()")
+      assert_style("a |> Enum.sort(:asc) |> Enum.reverse()", "Enum.sort(a, :desc)")
+      assert_style("a |> Enum.sort(:desc) |> Enum.reverse()", "Enum.sort(a, :asc)")
+      assert_style("a |> Enum.sort() |> Enum.reverse()", "Enum.sort(a, :desc)")
+    end
+
     test "reverse/concat" do
       assert_style("a |> Enum.reverse() |> Enum.concat()")
       assert_style("a |> Enum.reverse(bar) |> Enum.concat()")