Source code for clize.errors

# clize -- A command-line argument parser for Python
# Copyright (C) 2011-2016 by Yann Kaiser and contributors. See AUTHORS and
# COPYING for details.

from functools import partial

class UserError(ValueError):
    """An error to be printed to the user."""

    def __str__(self):
        return self.prefix_with_pname(super(UserError, self).__str__())

    def prefix_with_pname(self, message):
        return '{0}: {1}'.format(self.get_pname('Error'), message)

    def get_pname(self, default='command'):
            return self.pname
        except AttributeError:
            return default

class ArgumentError(UserError):
    """An error related to the arguments passed through the command-line
    def __init__(self, message=None):
        if message is not None:
            self.message = message

    def __str__(self):
        usage = ''
            usage = '\n' + '\n'.join(
        except Exception:
        return self.prefix_with_pname(self.message + usage)

[docs]class MissingRequiredArguments(ArgumentError): """Raised when required parameters have not been provided an argument""" def __init__(self, missing): self.missing = missing @property def message(self): return "Missing required arguments: {0}".format( ', '.join(arg.display_name for arg in self.missing))
[docs]class TooManyArguments(ArgumentError): """Raised when too many positional arguments have been passed for the parameters to consume.""" def __init__(self, extra): self.extra = extra @property def message(self): return "Received extra arguments: {0}".format( ' '.join(self.extra))
[docs]class DuplicateNamedArgument(ArgumentError): """Raised when a named option or flag has been passed twice.""" @property def message(self): return "{0} was specified more than once".format( self.param.aliases[0])
[docs]class UnknownOption(ArgumentError): """Raised when a named argument has no matching parameter.""" def __init__(self, name): = name @property def message(self): best_guess = None if best_guess = if best_guess: return "Unknown option {0!r}. Did you mean {1!r}?" \ .format(, best_guess) else: return "Unknown option {0!r}".format(
[docs]class MissingValue(ArgumentError): """Raised when an option received no value.""" @property def message(self): return "No value found after {0}".format(self.param.display_name)
[docs]class NotEnoughValues(ArgumentError): """Raised when MultiOptionParameter is given less values than its min parameter.""" @property def message(self): return "Received too few values for {0.display_name}".format( self.param)
[docs]class TooManyValues(ArgumentError): """Raised when MultiOptionParameter is given more values than its max parameter.""" @property def message(self): return "Received too many values for {0.display_name}".format( self.param)
[docs]class CliValueError(ValueError): """Specialization of `ValueError` for showing a message to the user along with the error rather than just the incorrect value."""
[docs]class BadArgumentFormat(ArgumentError): """Raised when an argument cannot be converted to the correct format.""" def __init__(self, text): self.text = text @property def message(self): return "Bad value for {0.display_name}: {1}".format( self.param, self.text)
[docs]class ArgsBeforeAlternateCommand(ArgumentError): """Raised when there are arguments before a non-fallback alternate command.""" def __init__(self, param): self.param = param @property def message(self): return "Arguments found before alternate action parameter {0}".format( self.param.display_name)
[docs]class SetErrorContext(object): """Context manager that sets attributes on exceptions that are raised past it""" def __init__(self, exc_type, **attributes): """ :param exc_type: The exception type to operate on. :param attributes: The attributes to set on the matching exceptions. They will only be set if yet unset on the exception. """ self.exc_type = exc_type self.values = attributes def __enter__(self): return self def __exit__(self, exc_type, exc_val, exc_tb): if isinstance(exc_val, self.exc_type): for key, val in self.values.items(): if not hasattr(exc_val, key): setattr(exc_val, key, val)
SetUserErrorContext = partial(SetErrorContext, UserError) SetArgumentErrorContext = partial(SetErrorContext, ArgumentError)