diff options
Diffstat (limited to 'cmd2/rl_utils.py')
| -rw-r--r-- | cmd2/rl_utils.py | 33 |
1 files changed, 24 insertions, 9 deletions
diff --git a/cmd2/rl_utils.py b/cmd2/rl_utils.py index 7f47db79..6278e859 100644 --- a/cmd2/rl_utils.py +++ b/cmd2/rl_utils.py @@ -32,6 +32,9 @@ rl_type = RlType.NONE # Tells if the terminal we are running in supports vt100 control characters vt100_support = False +# Explanation for why readline wasn't loaded +_rl_warn_reason = '' + # The order of this check matters since importing pyreadline will also show readline in the modules list if 'pyreadline' in sys.modules: rl_type = RlType.PYREADLINE @@ -113,15 +116,27 @@ if 'pyreadline' in sys.modules: elif 'gnureadline' in sys.modules or 'readline' in sys.modules: # We don't support libedit if 'libedit' not in readline.__doc__: - rl_type = RlType.GNU - - # Load the readline lib so we can access members of it - import ctypes - readline_lib = ctypes.CDLL(readline.__file__) - - # Check if we are running in a terminal - if sys.stdout.isatty(): - vt100_support = True + try: + # Load the readline lib so we can access members of it + import ctypes + readline_lib = ctypes.CDLL(readline.__file__) + except AttributeError: + _rl_warn_reason = ("this application is running in a non-standard Python environment in\n" + "which readline is not loaded dynamically from a shared library file") + else: + rl_type = RlType.GNU + if sys.stdout.isatty(): + vt100_support = True + +# Check if readline was loaded +if rl_type == RlType.NONE: + if not _rl_warn_reason: + _rl_warn_reason = ("no supported version of readline was found. To resolve this, install\n" + "pyreadline on Windows or gnureadline on Mac.") + rl_warning = ("Readline features including tab completion have been disabled because\n" + + _rl_warn_reason + '\n\n') +else: + rl_warning = '' # noinspection PyProtectedMember,PyUnresolvedReferences |