Error when using parentheses in arithmetic expansion

[ObserverOfTime]

This code is parsed "correctly":

echo $((1 + 2 - 3 * 4))

(command) ; [1:1 - 23]
 name: (command_name) ; [1:1 - 4]
  (word) ; [1:1 - 4]
 argument: (command_substitution) ; [1:6 - 23]
  (subshell) ; [1:8 - 22]
   (command) ; [1:9 - 21]
    name: (command_name) ; [1:9 - 9]
     (word) ; [1:9 - 9]
    argument: (word) ; [1:11 - 11]
    argument: (word) ; [1:13 - 13]
    argument: (word) ; [1:15 - 15]
    argument: (word) ; [1:17 - 17]
    argument: (word) ; [1:19 - 19]
    argument: (word) ; [1:21 - 21]

This code is not parsed correctly:

echo $((1 + (2 - 3) * 4))

(command) ; [1:1 - 24]
 name: (command_name) ; [1:1 - 4]
  (word) ; [1:1 - 4]
 argument: (command_substitution) ; [1:6 - 24]
  (ERROR) ; [1:8 - 21]
   (subshell) ; [1:8 - 19]
    (command) ; [1:9 - 18]
     name: (command_name) ; [1:9 - 9]
      (word) ; [1:9 - 9]
     argument: (concatenation) ; [1:11 - 14]
      (word) ; [1:11 - 11]
      (ERROR) ; [1:13 - 13]
      (word) ; [1:14 - 14]
     argument: (word) ; [1:16 - 16]
     argument: (word) ; [1:18 - 18]
   (special_variable_name) ; [1:21 - 21]
  (command) ; [1:23 - 23]
   name: (command_name) ; [1:23 - 23]
    (word) ; [1:23 - 23]
(ERROR) ; [1:25 - 25]

---

#55 should solve this issue if it is ever merged.

[LGFae]

I am also running into this issue with some scripts of mine.