Do not escape quoted keywords on formatting, closes #7451

2 files changed, 12 insertions, 1 deletions

diff --git a/lib/elixir/lib/code/formatter.ex b/lib/elixir/lib/code/formatter.ex
index fe37663f9..c1ee99e23 100644
--- a/lib/elixir/lib/code/formatter.ex
+++ b/lib/elixir/lib/code/formatter.ex
@@ -555,7 +555,16 @@ defmodule Code.Formatter do
         {left, state} =
           case left_arg do
             {:__block__, _, [atom]} when is_atom(atom) ->
-              {atom |> Code.Identifier.inspect_as_key() |> string(), state}
+              key =
+                case Code.Identifier.classify(atom) do
+                  type when type in [:callable_local, :callable_operator, :not_callable] ->
+                    IO.iodata_to_binary([Atom.to_string(atom), ?:])
+
+                  _ ->
+                    IO.iodata_to_binary([?", Atom.to_string(atom), ?", ?:])
+                end
+
+              {string(key), state}
 
             {{:., _, [:erlang, :binary_to_atom]}, _, [{:<<>>, _, entries}, :utf8]} ->
               interpolation_to_algebra(entries, @double_quote, state, "\"", "\":")
diff --git a/lib/elixir/test/elixir/code_formatter/containers_test.exs b/lib/elixir/test/elixir/code_formatter/containers_test.exs
index 89989d78f..0c3b5fc27 100644
--- a/lib/elixir/test/elixir/code_formatter/containers_test.exs
+++ b/lib/elixir/test/elixir/code_formatter/containers_test.exs
@@ -200,6 +200,8 @@ defmodule Code.Formatter.ContainersTest do
     test "with quoted keyword lists" do
       assert_same ~S(["with spaces": 1])
       assert_same ~S(["one #{two} three": 1])
+      assert_same ~S(["\w": 1, "\\w": 2])
+      assert_same ~S(["Elixir.Foo": 1, "Elixir.Bar": 2])
       assert_format ~S(["Foo": 1, "Bar": 2]), ~S([Foo: 1, Bar: 2])
     end