properly handle iodata

Author: lukaszsamson

apps/language_server/lib/language_server/providers/execute_command/expand_macro.ex

@@ -31,7 +31,7 @@ defmodule ElixirLS.LanguageServer.Providers.ExecuteCommand.ExpandMacro do
             |> Macro.camelize()
             |> String.replace("Expand", "expand")
 
-          formatted = value |> Code.format_string!() |> List.to_string()
+          formatted = value |> Code.format_string!() |> IO.iodata_to_binary()
           {key, formatted <> "\n"}
         end)
 

apps/language_server/lib/language_server/providers/hover.ex

@@ -280,7 +280,7 @@ defmodule ElixirLS.LanguageServer.Providers.Hover do
   defp format_header(text) do
     text
     |> Code.format_string!(line_length: 40)
-    |> to_string
+    |> IO.iodata_to_binary()
   rescue
     _ ->
       # Code.format_string! can raise SyntaxError e.g.

apps/language_server/lib/language_server/source_file.ex

@@ -222,7 +222,6 @@ defmodule ElixirLS.LanguageServer.SourceFile do
       case format_code(spec, line_length: line_length) do
         {:ok, code} ->
           code
-          |> to_string()
 
         {:error, _} ->
           spec
@@ -322,7 +321,7 @@ defmodule ElixirLS.LanguageServer.SourceFile do
 
   defp format_code(code, opts) do
     try do
-      {:ok, Code.format_string!(code, opts)}
+      {:ok, Code.format_string!(code, opts) |> IO.iodata_to_binary()}
     rescue
       e ->
         {:error, e}