Fix formatting of lists in module attribues (#11462)

Author: doorgan

lib/elixir/lib/code/normalizer.ex

@@ -200,10 +200,15 @@ defmodule Code.Normalizer do
   # Module attributes
   defp do_normalize({:@, meta, [{name, name_meta, [value]}]}, state) do
     value =
-      if is_list(value) do
-        normalize_kw_args(value, state, false)
-      else
-        do_normalize(value, state)
+      cond do
+        keyword?(value) ->
+          normalize_kw_args(value, state, true)
+
+        is_list(value) ->
+          normalize_literal(value, meta, state)
+
+        true ->
+          do_normalize(value, state)
       end
 
     {:@, meta, [{name, name_meta, [value]}]}

lib/elixir/test/elixir/code_normalizer/formatted_ast_test.exs

@@ -164,6 +164,12 @@ defmodule Code.Normalizer.FormatterASTTest do
     end
   end
 
+  describe "lists" do
+    test "on module attribute" do
+      assert_same ~S"@foo [1]"
+    end
+  end
+
   describe "charlists" do
     test "without escapes" do
       assert_same ~S['']

lib/elixir/test/elixir/code_normalizer/quoted_ast_test.exs

@@ -542,6 +542,26 @@ defmodule Code.Normalizer.QuotedASTTest do
       assert quoted_to_string(quote(do: foo(catch: a))) == "foo(catch: a)"
       assert quoted_to_string(quote(do: foo |> [bar: :baz])) == "foo |> [bar: :baz]"
     end
+
+    test "list in module attribute" do
+      assert quoted_to_string(
+               quote do
+                 @foo [1]
+               end
+             ) == "@foo [1]"
+
+      assert quoted_to_string(
+               quote do
+                 @foo [foo: :bar]
+               end
+             ) == "@foo foo: :bar"
+
+      assert quoted_to_string(
+               quote do
+                 @foo [1, foo: :bar]
+               end
+             ) == "@foo [1, foo: :bar]"
+    end
   end
 
   describe "quoted_to_algebra/2 escapes" do