remove Python 2 crumbs

tests/test_nesting.py

@@ -1,8 +1,4 @@
 # -*- coding: utf-8 -*-
-try:
-    from builtins import object
-except ImportError:
-    pass
 
 import sys
 import tempfile
@@ -36,7 +32,7 @@
 default_separator = NestedState.separator
 
 
-class Dummy(object):
+class Dummy:
     pass
 
 

transitions/core.py

@@ -6,23 +6,7 @@
     and transition concepts.
 """
 
-
-try:
-    from builtins import object
-except ImportError:  # pragma: no cover
-    # python2
-    pass
-
-try:
-    # Enums are supported for Python 3.4+ and Python 2.7 with enum34 package installed
-    from enum import Enum, EnumMeta
-except ImportError:  # pragma: no cover
-    # If enum is not available, create dummy classes for type checks
-    class Enum:  # type:ignore
-        """This is just an Enum stub for Python 2 and Python 3.3 and before without Enum support."""
-
-    class EnumMeta:  # type:ignore
-        """This is just an EnumMeta stub for Python 2 and Python 3.3 and before without Enum support."""
+from enum import Enum, EnumMeta
 
 import inspect
 import itertools
@@ -31,7 +15,6 @@ class EnumMeta:  # type:ignore
 
 from collections import OrderedDict, defaultdict, deque
 from functools import partial
-from six import string_types
 
 _LOGGER = logging.getLogger(__name__)
 _LOGGER.addHandler(logging.NullHandler())
@@ -838,7 +821,7 @@ def add_states(self, states, on_enter=None, on_exit=None,
         states = listify(states)
 
         for state in states:
-            if isinstance(state, (string_types, Enum)):
+            if isinstance(state, (str, Enum)):
                 state = self._create_state(
                     state, on_enter=on_enter, on_exit=on_exit,
                     ignore_invalid_triggers=ignore, **kwargs)
@@ -1204,7 +1187,7 @@ def resolve_callable(func, event_data):
         Returns:
             callable function resolved from string or func
         """
-        if isinstance(func, string_types):
+        if isinstance(func, str):
             try:
                 func = getattr(event_data.model, func)
                 if not callable(func):  # if a property or some other not callable attribute was passed

transitions/extensions/diagrams_base.py

@@ -8,14 +8,12 @@
 import copy
 import abc
 import logging
-import six
 
 _LOGGER = logging.getLogger(__name__)
 _LOGGER.addHandler(logging.NullHandler())
 
 
-@six.add_metaclass(abc.ABCMeta)
-class BaseGraph(object):
+class BaseGraph(metaclass=abc.ABCMeta):
     """Provides the common foundation for graphs generated either with pygraphviz or graphviz. This abstract class
     should not be instantiated directly. Use .(py)graphviz.(Nested)Graph instead.
     Attributes:

transitions/extensions/factory.py

@@ -9,7 +9,6 @@
 
 from functools import partial
 import itertools
-from six import iteritems
 
 from ..core import Machine, Transition
 
@@ -34,7 +33,7 @@ class NestedAsyncTransition(NestedTransition):  # type: ignore
         """A mock of NestedAsyncTransition for Python 3.6 and earlier."""
 
 
-class MachineFactory(object):
+class MachineFactory:
     """Convenience factory for machine class retrieval."""
 
     # get one of the predefined classes which fulfill the criteria
@@ -78,7 +77,7 @@ def format_references(func):
                 ", ".join(itertools.chain(
                     (str(_) for _ in func.args[1:]),
                     ("%s=%s" % (key, value)
-                     for key, value in iteritems(func.keywords if func.keywords else {})))))
+                     for key, value in (func.keywords.items() if func.keywords else {}.items())))))
         return GraphMachine.format_references(func)
 
 

transitions/extensions/markup.py

@@ -7,25 +7,12 @@
     also be used to store and transfer machines.
 """
 
+from enum import Enum, EnumMeta
 from functools import partial
 import importlib
 import itertools
 import numbers
 
-from six import string_types, iteritems
-
-try:
-    # Enums are supported for Python 3.4+ and Python 2.7 with enum34 package installed
-    from enum import Enum, EnumMeta
-except ImportError:  # pragma: no cover
-    # If enum is not available, create dummy classes for type checks
-    # typing must be prevented redefinition issues with mypy
-    class Enum:  # type:ignore
-        """This is just an Enum stub for Python 2 and Python 3.3 and before without Enum support."""
-
-    class EnumMeta:  # type:ignore
-        """This is just an EnumMeta stub for Python 2 and Python 3.3 and before without Enum support."""
-
 from ..core import Machine
 from .nesting import HierarchicalMachine
 
@@ -143,7 +130,7 @@ def format_references(func):
                 ", ".join(itertools.chain(
                     (str(_) for _ in func.args),
                     ("%s=%s" % (key, value)
-                     for key, value in iteritems(func.keywords if func.keywords else {})))))
+                     for key, value in (func.keywords.items() if func.keywords else {}.items())))))
         return str(func)
 
     def _convert_states_and_transitions(self, root):
@@ -236,7 +223,7 @@ class HierarchicalMarkupMachine(MarkupMachine, HierarchicalMachine):
 
 def rep(func, format_references=None):
     """Return a string representation for `func`."""
-    if isinstance(func, string_types):
+    if isinstance(func, str):
         return func
     if isinstance(func, numbers.Number):
         return str(func)
@@ -249,7 +236,7 @@ def _convert(obj, attributes, format_references):
         val = getattr(obj, key, False)
         if not val:
             continue
-        if isinstance(val, string_types):
+        if isinstance(val, str):
             definition[key] = val
         elif val is True:
             definition[key] = True

transitions/extensions/nesting.py

@@ -9,23 +9,11 @@
 
 from collections import OrderedDict
 import copy
+from enum import Enum, EnumMeta
 from functools import partial, reduce
 import inspect
 import logging
 
-try:
-    # Enums are supported for Python 3.4+ and Python 2.7 with enum34 package installed
-    from enum import Enum, EnumMeta
-except ImportError:  # pragma: no cover
-    # If enum is not available, create dummy classes for type checks
-    class Enum:  # type: ignore
-        """This is just an Enum stub for Python 2 and Python 3.3 and before without Enum support."""
-
-    class EnumMeta:  # type: ignore
-        """This is just an EnumMeta stub for Python 2 and Python 3.3 and before without Enum support."""
-
-from six import string_types
-
 from ..core import State, Machine, Transition, Event, listify, MachineError, EventData
 
 _LOGGER = logging.getLogger(__name__)
@@ -414,7 +402,7 @@ def __init__(self, model=Machine.self_literal, states=None, initial='initial', t
         )
 
     def __call__(self, to_scope=None):
-        if isinstance(to_scope, string_types):
+        if isinstance(to_scope, str):
             state_name = to_scope.split(self.state_cls.separator)[0]
             state = self.states[state_name]
             to_scope = (state, state.states, state.events, self.prefix_path + [state_name])
@@ -448,7 +436,7 @@ def add_model(self, model, initial=None):
         if hasattr(initial_name, 'name'):
             initial_name = initial_name.name
         # initial states set by add_model or machine might contain initial states themselves.
-        if isinstance(initial_name, string_types):
+        if isinstance(initial_name, str):
             initial_states = self._resolve_initial(models, initial_name.split(self.state_cls.separator))
         # when initial is set to a (parallel) state, we accept it as it is
         else:
@@ -513,7 +501,7 @@ def add_states(self, states, on_enter=None, on_exit=None, ignore_invalid_trigger
                     state = {'name': state, 'children': state.value}
                 elif isinstance(state.value, dict):
                     state = dict(name=state, **state.value)
-            if isinstance(state, string_types):
+            if isinstance(state, str):
                 self._add_string_state(state, on_enter, on_exit, ignore, remap, **kwargs)
             elif isinstance(state, Enum):
                 self._add_enum_state(state, on_enter, on_exit, ignore, remap, **kwargs)
@@ -640,7 +628,7 @@ def get_state(self, state, hint=None):
         """
         if isinstance(state, Enum):
             state = self._get_enum_path(state)
-        elif isinstance(state, string_types):
+        elif isinstance(state, str):
             state = state.split(self.state_cls.separator)
         if not hint:
             state = copy.copy(state)
@@ -692,11 +680,11 @@ def get_transitions(self, trigger="", source="*", dest="*", delegate=False):
         """
         with self():
             source_path = [] if source == "*" \
-                else source.split(self.state_cls.separator) if isinstance(source, string_types) \
+                else source.split(self.state_cls.separator) if isinstance(source, str) \
                 else self._get_enum_path(source) if isinstance(source, Enum) \
                 else self._get_state_path(source)
             dest_path = [] if dest == "*" \
-                else dest.split(self.state_cls.separator) if isinstance(dest, string_types) \
+                else dest.split(self.state_cls.separator) if isinstance(dest, str) \
                 else self._get_enum_path(dest) if isinstance(dest, Enum) \
                 else self._get_state_path(dest)
             matches = self.get_nested_transitions(trigger, source_path, dest_path)
@@ -1166,7 +1154,7 @@ def _init_state(self, state):
                 self._init_state(substate)
 
     def _recursive_initial(self, value):
-        if isinstance(value, string_types):
+        if isinstance(value, str):
             path = value.split(self.state_cls.separator, 1)
             if len(path) > 1:
                 state_name, suffix = path