Run pyupgrade to clean up Python 2 syntaxes

Update all .py source files by
 $ pyupgrade --py3-only $(git ls-files | grep ".py$")
to modernize the code according to Python 3 syntaxes.

pep8 errors are fixed by
 $ autopep8 --select=E127,E128,E501 --max-line-length 79 -r \
    --in-place automaton

Also add the pyupgrade hook to pre-commit to avoid merging additional
Python 2 syntaxes.

Change-Id: Ic81c8d6f1270895437132bfccd676c79e6dfce30

.pre-commit-config.yaml

@@ -23,3 +23,8 @@ repos:
     hooks:
       - id: hacking
         additional_dependencies: []
+  - repo: https://github.com/asottile/pyupgrade
+    rev: v3.18.0
+    hooks:
+      - id: pyupgrade
+        args: [--py3-only]

automaton/exceptions.py

@@ -37,4 +37,4 @@ class FrozenMachine(AutomatonException):
     """Exception raised when a frozen machine is modified."""
 
     def __init__(self):
-        super(FrozenMachine, self).__init__("Frozen machine can't be modified")
+        super().__init__("Frozen machine can't be modified")

automaton/machines.py

@@ -20,7 +20,7 @@ from automaton import _utils as utils
 from automaton import exceptions as excp
 
 
-class State(object):
+class State:
     """Container that defines needed components of a single state.
 
     Usage of this and the :meth:`~.FiniteMachine.build` make creating finite
@@ -58,7 +58,7 @@ def _orderedkeys(data, sort=True):
         return list(data)
 
 
-class _Jump(object):
+class _Jump:
     """A FSM transition tracks this data while jumping."""
     def __init__(self, name, on_enter, on_exit):
         self.name = name
@@ -66,7 +66,7 @@ class _Jump(object):
         self.on_exit = on_exit
 
 
-class FiniteMachine(object):
+class FiniteMachine:
     """A finite state machine.
 
     This state machine can be used to automatically run a given set of
@@ -413,7 +413,7 @@ class FiniteMachine(object):
                 postfix_markings.append("^")
             if self._states[state]['terminal']:
                 postfix_markings.append("$")
-            pretty_state = "%s%s" % ("".join(prefix_markings), state)
+            pretty_state = "{}{}".format("".join(prefix_markings), state)
             if postfix_markings:
                 pretty_state += "[%s]" % "".join(postfix_markings)
             if self._transitions[state]:
@@ -453,7 +453,7 @@ class HierarchicalFiniteMachine(FiniteMachine):
                                     'reaction,terminal,machine')
 
     def __init__(self):
-        super(HierarchicalFiniteMachine, self).__init__()
+        super().__init__()
         self._nested_machines = {}
 
     @classmethod
@@ -475,15 +475,15 @@ class HierarchicalFiniteMachine(FiniteMachine):
         if machine is not None and not isinstance(machine, FiniteMachine):
             raise ValueError(
                 "Nested state machines must themselves be state machines")
-        super(HierarchicalFiniteMachine, self).add_state(
+        super().add_state(
             state, terminal=terminal, on_enter=on_enter, on_exit=on_exit)
         if machine is not None:
             self._states[state]['machine'] = machine
             self._nested_machines[state] = machine
 
     def copy(self, shallow=False, unfreeze=False):
-        c = super(HierarchicalFiniteMachine, self).copy(shallow=shallow,
-                                                        unfreeze=unfreeze)
+        c = super().copy(shallow=shallow,
+                         unfreeze=unfreeze)
         if shallow:
             c._nested_machines = self._nested_machines
         else:
@@ -512,7 +512,7 @@ class HierarchicalFiniteMachine(FiniteMachine):
                                            also be used to initialize any state
                                            machines they contain (recursively).
         """
-        super(HierarchicalFiniteMachine, self).initialize(
+        super().initialize(
             start_state=start_state)
         for data in self._states.values():
             if 'machine' in data:

automaton/runners.py

@@ -61,7 +61,7 @@ class FiniteRunner(Runner):
         """Create a runner for the given machine."""
         if not isinstance(machine, (machines.FiniteMachine,)):
             raise TypeError("FiniteRunner only works with FiniteMachine(s)")
-        super(FiniteRunner, self).__init__(machine)
+        super().__init__(machine)
 
     def run(self, event, initialize=True):
         for transition in self.run_iter(event, initialize=initialize):
@@ -104,7 +104,7 @@ class HierarchicalRunner(Runner):
         if not isinstance(machine, (machines.HierarchicalFiniteMachine,)):
             raise TypeError("HierarchicalRunner only works with"
                             " HierarchicalFiniteMachine(s)")
-        super(HierarchicalRunner, self).__init__(machine)
+        super().__init__(machine)
 
     def run(self, event, initialize=True):
         for transition in self.run_iter(event, initialize=initialize):

automaton/tests/test_fsm.py

@@ -39,7 +39,7 @@ class FSMTest(testcase.TestCase):
         return m
 
     def setUp(self):
-        super(FSMTest, self).setUp()
+        super().setUp()
         # NOTE(harlowja): this state machine will never stop if run() is used.
         self.jumper = self._create_fsm("down", add_states=['up', 'down'])
         self.jumper.add_transition('down', 'up', 'jump')

doc/source/conf.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # Copyright (C) 2020 Red Hat, Inc.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");

releasenotes/source/conf.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
 # You may obtain a copy of the License at