Avoid interpolation which would convert char lists twice

Author: José Valim

lib/mix/lib/mix/shell.ex

@@ -60,15 +60,15 @@ defmodule Mix.Shell do
  { :unix, _ } ->
  command = command
  |> String.replace("\"", "\\\"")
- |> :binary.bin_to_list # We need to send bytes, not chars
- %c(sh -c "#{command}")
+ |> :binary.bin_to_list
+ 'sh -c ' ++ command
 
  { :win32, osname } ->
- command = to_char_list(command)
+ command = :binary.bin_to_list(command)
  case { System.get_env("COMSPEC"), osname } do
- { nil, :windows } -> 'command.com /c #{command}'
- { nil, _ } -> 'cmd /c #{command}'
- { cmd, _ } -> '#{cmd} /c #{command}'
+ { nil, :windows } -> 'command.com /c ' ++ command
+ { nil, _ } -> 'cmd /c ' ++ command
+ { cmd, _ } -> '#{cmd} /c ' ++ command
  end
  end
  end