"""
import re
+import inspect
import logging ; log = logging.getLogger('pymin.dispatcher')
-__ALL__ = ('Error', 'HandlerError', 'CommandNotFoundError', 'Handler',
+__all__ = ('Error', 'HandlerError', 'CommandNotFoundError', 'Handler',
'Dispatcher', 'handler', 'is_handler', 'get_help')
class Error(RuntimeError):
return u'Error in command "%s".' % u' '.join(self.command)
class WrongArgumentsError(CommandError):
- r"""WrongArgumentsError(handler, message) -> WrongArgumentsError instance.
+ r"""WrongArgumentsError(handler, error) -> WrongArgumentsError instance.
This exception is raised when an empty command string is received.
"""
- def __init__(self, handler, message):
+ def __init__(self, handler, error):
r"Initialize the object, see class documentation for more info."
self.handler = handler
- self.message = message
+ self.error = error
+
+ args_re = re.compile(r'\w+\(\) takes (.+) (\d+) \w+ \((\d+) given\)')
+
+ extra_kw_re = re.compile(r'\w+\(\) got an unexpected keyword argument (.+)')
+
+ dup_kw_re = re.compile(r'\w+\(\) got multiple values for keyword argument '
+ r"'(.+)'")
+
+ def format(self):
+ r"format() -> unicode - Format a TypeError to adapt it to a command."
+ m = self.args_re.match(unicode(self.error))
+ if m:
+ (quant, n_ok, n_bad) = m.groups()
+ n_ok = int(n_ok)
+ n_bad = int(n_bad)
+ n_ok -= 1
+ n_bad -= 1
+ pl = ''
+ if n_ok != 1:
+ pl = 's'
+ return u'takes %s %s argument%s, %s given' \
+ % (quant, n_ok, pl, n_bad)
+ m = self.extra_kw_re.match(unicode(self.error))
+ if m:
+ (kw,) = m.groups()
+ return u'got an unexpected keyword argument %s' % kw
+ m = self.dup_kw_re.match(unicode(self.error))
+ if m:
+ (kw,) = m.groups()
+ return u'got multiple values for argument %s' % kw
+ return u'got wrong arguments'
def __unicode__(self):
- return u'Command "%s" %s.' % (self.handler.__name__, self.message)
+ return u'Command "%s" %s.' % (self.handler.__name__, self.format())
class CommandNotSpecifiedError(CommandError):
r"""CommandNotSpecifiedError() -> CommandNotSpecifiedError instance.
"""
if not help:
raise TypeError("'help' should not be empty")
- def wrapper(f):
- f._dispatcher_handler = True
- f.handler_help = help
- return f
- return wrapper
+ def make_wrapper(f):
+ log.debug('handler(): Decorating %s()', f.__name__)
+ # Here comes the tricky part:
+ # We need to make our wrapped function to accept any number of
+ # positional and keyword arguments, but checking for the correct
+ # arguments and raising an exception in case the arguments doesn't
+ # match.
+ # So we create a dummy function, with the same signature as the
+ # wrapped one, so we can check later (at "dispatch-time") if the
+ # real function call will be successful. If the dummy function don't
+ # raise a TypeError, the arguments are just fine.
+ env = dict()
+ argspec = inspect.getargspec(f)
+ signature = inspect.formatargspec(*argspec)
+ # The dummy function
+ exec "def f%s: pass" % signature in env
+ signature_check = env['f']
+ # The wrapper to check the signature at "dispatch-time"
+ def wrapper(*args, **kwargs):
+ # First we check if the arguments passed are OK.
+ try:
+ signature_check(*args, **kwargs)
+ except TypeError, e:
+ # If not, we raise an appropriate error.
+ raise WrongArgumentsError(f, e)
+ # If they are fine, we call the real function
+ return f(*args, **kwargs)
+ # Some flag to mark our handlers for simple checks
+ wrapper._dispatcher_handler = True
+ # The help string we asked for in the first place =)
+ wrapper.handler_help = help
+ # We store the original signature for better help generation
+ wrapper.handler_argspec = argspec
+ # And some makeup, to make our wrapper look like the original function
+ wrapper.__name__ = f.__name__
+ wrapper.__dict__.update(f.__dict__)
+ # We add a hint in the documentation
+ wrapper.__doc__ = "Pymin handler with signature: %s%s" \
+ % (wrapper.__name__, signature)
+ if f.__doc__ is not None:
+ wrapper.__doc__ += "\n\n" + f.__doc__
+ wrapper.__module__ = f.__module__
+ return wrapper
+ return make_wrapper
def is_handler(handler):
r"is_handler(handler) -> bool :: Tell if a object is a handler."
register_token(buff, keyword, seq, dic)
return (seq, dic)
-args_re = re.compile(r'\w+\(\) takes (.+) (\d+) \w+ \((\d+) given\)')
-kw_re = re.compile(r'\w+\(\) got an unexpected keyword argument (.+)')
-
class Dispatcher:
r"""Dispatcher([root]) -> Dispatcher instance :: Command dispatcher.
route = route[1:]
log.debug(u'Dispatcher.dispatch: %r is a handler, calling it with '
u'route=%r, kwargs=%r', handler, route, kwargs)
- try:
- r = handler(*route, **kwargs)
- log.debug(u'Dispatcher.dispatch: handler returned %s', r)
- return r
- except TypeError, e:
- log.debug(u'Dispatcher.dispatch: type error (%r)', e)
- m = args_re.match(unicode(e))
- if m:
- (quant, n_ok, n_bad) = m.groups()
- n_ok = int(n_ok)
- n_bad = int(n_bad)
- n_ok -= 1
- n_bad -= 1
- pl = ''
- if n_ok > 1:
- pl = 's'
- e = WrongArgumentsError(handler, u'takes %s %s argument%s, '
- '%s given' % (quant, n_ok, pl, n_bad))
- log.debug(u'Dispatcher.dispatch: wrong arguments (%r)', e)
- raise e
- m = kw_re.match(unicode(e))
- if m:
- (kw,) = m.groups()
- e = WrongArgumentsError(handler,
- u'got an unexpected keyword argument %s' % kw)
- log.debug(u'Dispatcher.dispatch: wrong arguments (%r)', e)
- raise e
- log.debug(u'Dispatcher.dispatch: some other TypeError, re-raising')
- raise
+ r = handler(*route, **kwargs)
+ log.debug(u'Dispatcher.dispatch: handler returned %s', r)
+ return r
if __name__ == '__main__':
def cmd1(self, *args):
print 'class.cmd1:', args
@handler(u"cmd2: Print all the arguments, return nothing")
- def cmd2(self, *args):
- print 'class.cmd2:', args
+ def cmd2(self, arg1, arg2):
+ print 'class.cmd2:', arg1, arg2
subclass = TestClassSubHandler()
class RootHandler(Handler):
d = Dispatcher(RootHandler())
- d.dispatch(r'''func arg1 arg2 arg3 "fourth 'argument' with \", a\ttab and\n\\n"''')
- print 'inst commands:', tuple(d.dispatch('inst commands'))
- print 'inst help:', d.dispatch('inst help')
- d.dispatch('inst cmd1 arg1 arg2 arg3 arg4')
- d.dispatch('inst cmd2 arg1 arg2')
- print 'inst subclass help:', d.dispatch('inst subclass help')
- d.dispatch('inst subclass subcmd arg1 arg2 arg3 arg4 arg5')
+ r = d.dispatch(r'''func arg1 arg2 arg3 "fourth 'argument' with \", a\ttab and\n\\n"''')
+ assert r is None
+ r = list(d.dispatch('inst commands'))
+ r.sort()
+ assert r == ['cmd1', 'cmd2', 'commands', 'help']
+ print 'inst commands:', r
+ r = d.dispatch('inst help')
+ assert r == {
+ 'commands': u'List available commands',
+ 'subclass': u'Undocumented handler',
+ 'cmd1': u'cmd1: Print all the arguments, return nothing',
+ 'cmd2': u'cmd2: Print all the arguments, return nothing',
+ 'help': u'Show available commands with their help'
+ }
+ print 'inst help:', r
+ r = d.dispatch('inst cmd1 arg1 arg2 arg3 arg4')
+ assert r is None
+ r = d.dispatch('inst cmd2 arg1 arg2')
+ assert r is None
+ r = d.dispatch('inst subclass help')
+ assert r == {
+ 'subcmd': u'subcmd: Print all the arguments, return nothing',
+ 'commands': u'List available commands',
+ 'help': u'Show available commands with their help'
+ }
+ print 'inst subclass help:', r
+ r = d.dispatch('inst subclass subcmd arg1 arg2 arg3 arg4 arg5')
+ assert r is None
try:
d.dispatch('')
+ assert False, 'It should raised a CommandNotSpecifiedError'
except CommandNotSpecifiedError, e:
print 'Not found:', e
try:
d.dispatch('sucutrule piquete culete')
+ assert False, 'It should raised a CommandNotFoundError'
except CommandNotFoundError, e:
print 'Not found:', e
try:
d.dispatch('inst cmd3 arg1 arg2 arg3')
+ assert False, 'It should raised a CommandNotInHandlerError'
except CommandNotInHandlerError, e:
print 'Not found:', e
try:
d.dispatch('inst')
+ assert False, 'It should raised a CommandIsAHandlerError'
except CommandIsAHandlerError, e:
print 'Not found:', e
+ try:
+ d.dispatch('inst cmd2 "just one arg"')
+ assert False, 'It should raised a WrongArgumentsError'
+ except WrongArgumentsError, e:
+ print 'Bad arguments:', e
+ try:
+ d.dispatch('inst cmd2 arg1 arg2 "an extra argument"')
+ assert False, 'It should raised a WrongArgumentsError'
+ except WrongArgumentsError, e:
+ print 'Bad arguments:', e
+ try:
+ d.dispatch('inst cmd2 arg1 arg2 arg3="unexpected keyword arg"')
+ assert False, 'It should raised a WrongArgumentsError'
+ except WrongArgumentsError, e:
+ print 'Bad arguments:', e
+ try:
+ d.dispatch('inst cmd2 arg1 arg2 arg2="duplicated keyword arg"')
+ assert False, 'It should raised a WrongArgumentsError'
+ except WrongArgumentsError, e:
+ print 'Bad arguments:', e
print
print
assert p == ([u'\\None'], {}), p
try:
p = parse_command('hello=')
+ assert False, p + ' should raised a ParseError'
except ParseError, e:
pass
- else:
- assert False, p + ' should raised a ParseError'
try:
p = parse_command('"hello')
+ assert False, p + ' should raised a ParseError'
except ParseError, e:
pass
- else:
- assert False, p + ' should raised a ParseError'
projects / software / pymin.git / blobdiff