===========================================
One empty quoted argument [quoted_argument]
===========================================

message("")

---
(source_file
 (command_invocation
  (normal_command
   (identifier)
   (arguments
    (argument (quoted_argument))
   )
  )
 )
 )

=====================================
One quoted argument [quoted_argument] 
=====================================

message("An argument")

---
(source_file
 (command_invocation
  (normal_command
   (identifier)
   (arguments
    (argument (quoted_argument (quoted_element)))
   )
  )
 )
 )

======================================
Two quoted arguments [quoted_argument] 
======================================

message("First argument" "Second argument")

---
(source_file
 (command_invocation
  (normal_command
   (identifier)
   (arguments
    (argument (quoted_argument (quoted_element)))
    (seperation (space))
    (argument (quoted_argument (quoted_element)))
   )
  )
 )
 )

===================================================
A quoted argument with line break [quoted_argument] 
===================================================

message("An argument
with line break")

---
(source_file
 (command_invocation
  (normal_command
   (identifier)
   (arguments
    (argument (quoted_argument (quoted_element)))
   )
  )
 )
 )

========================================
One variable reference [quoted_argument] 
========================================

message("${var}")

---
(source_file
 (command_invocation
  (normal_command
   (identifier)
   (arguments
    (argument
     (quoted_argument
      (quoted_element
       (variable_ref (normal_var (variable)))
      )
     )
    )
   )
  )
 )
 )

=========================================
Two Variable references [quoted_argument] 
=========================================

message("${var} ${var}")

---
(source_file
 (command_invocation
  (normal_command
   (identifier)
   (arguments
    (argument
     (quoted_argument
      (quoted_element
       (variable_ref (normal_var (variable)))
       (variable_ref (normal_var (variable)))
      )
     )
    )
   )
  )
 )
 )