特に Windows で rshell を pip install rshell でインストールしても rshell を実行しようにもエラーをだして動かない場面に直面することがあります。

エラーの例

C:\MyProject\aaa> rshell
Traceback (most recent call last):
  File "<frozen runpy>", line 198, in _run_module_as_main
  File "<frozen runpy>", line 88, in _run_code
  File "C:\Users\Hoge\AppData\Local\Programs\Python\Python311\Scripts\rshell.exe\__main__.py", line 4, in <module>
  File "C:\Users\Hoge\AppData\Local\Programs\Python\Python311\Lib\site-packages\rshell\command_line.py", line 1, in <module>
    import rshell.main
  File "C:\Users\Hoge\AppData\Local\Programs\Python\Python311\Lib\site-packages\rshell\main.py", line 80, in <module>
    import readline
  File "C:\Users\Hoge\AppData\Local\Programs\Python\Python311\Lib\site-packages\readline.py", line 34, in <module>
    rl = Readline()
         ^^^^^^^^^^
  File "C:\Users\Hoge\AppData\Local\Programs\Python\Python311\Lib\site-packages\pyreadline\rlmain.py", line 422, in __init__
    BaseReadline.__init__(self)
  File "C:\Users\Hoge\AppData\Local\Programs\Python\Python311\Lib\site-packages\pyreadline\rlmain.py", line 62, in __init__
    mode.init_editing_mode(None)
  File "C:\Users\Hoge\AppData\Local\Programs\Python\Python311\Lib\site-packages\pyreadline\modes\emacs.py", line 633, in init_editing_mode
    self._bind_key('space',       self.self_insert)
  File "C:\Users\Hoge\AppData\Local\Programs\Python\Python311\Lib\site-packages\pyreadline\modes\basemode.py", line 162, in _bind_key
    if not callable(func):
           ^^^^^^^^^^^^^^
  File "C:\Users\Hoge\AppData\Local\Programs\Python\Python311\Lib\site-packages\pyreadline\py3k_compat.py", line 8, in callable
    return isinstance(x, collections.Callable)
                         ^^^^^^^^^^^^^^^^^^^^
AttributeError: module 'collections' has no attribute 'Callable'

原因

${PYTHONPATH}\Lib\site-packages\pyreadline\py3k_compat.py このファイルに不具合があるからです。

対策方法

py3k_compat.py を以下の通りソースコードを修正すれば回避できます。

--- py3k_compat.py.orig 2023-08-17 22:45:26.488592900 +0900
+++ py3k_compat.py      2023-08-17 21:32:57.439240300 +0900
@@ -5,7 +5,7 @@ if sys.version_info[0] >= 3:
     import collections
     PY3 = True
     def callable(x):
-        return isinstance(x, collections.Callable)
+        return isinstance(x, collections.abc.Callable)

     def execfile(fname, glob, loc=None):
         loc = loc if (loc is not None) else glob