feat: drop support for Python 2

- Removed Python 2 references and infrastructure
- Automatically applied [ruff fixes for Python 2 deprecations](https://docs.astral.sh/ruff/rules/#pyupgrade-up):
  - UP004 - useless-object-inheritance - Class {name} inherits from object
  - UP008 - super-call-with-parameters - Use super() instead of super(__class__, self)
  - UP009 - utf8-encoding-declaration - UTF-8 encoding declaration is unnecessary
  - UP020 - open-alias - Use builtin open
  - UP025 - unicode-kind-prefix - Remove unicode literals from strings
  - UP030 - format-literals - Use implicit references for positional format fields
- Manually resolved `UP036` deprecations (outdated-version-block)
- Dropped deprecated `MAINTAINER` property from `Dockerfile`

.travis.yml

@@ -2,15 +2,14 @@ language: python
 os: linux
 dist: xenial
 python:
-    - "2.7"
     - "3.6"
     - "3.7"
     - "3.8"
     - "3.9"
     - "pypy3.5"
 install:
     - pip install .
-    - pip install -r test_requirements.txt
+    - pip install --requirement test_requirements.txt
 script:
     - make tests
     - make cov

Dockerfile

@@ -1,15 +1,11 @@
 FROM alpine:edge
-MAINTAINER rubik
+LABEL maintainer="rubik"
 
 WORKDIR /usr/src/app
 COPY . /usr/src/app
 
 RUN apk --update add \
-  python2 python3 py2-pip && \
-  pip2 install --upgrade pip && \
-  pip2 install --requirement requirements.txt && \
-  pip2 install . && \
-  mv /usr/bin/radon /usr/bin/radon2 && \
+  python3 py3-pip && \
   pip3 install --requirement requirements.txt && \
   pip3 install . && \
   mv /usr/bin/radon /usr/bin/radon3 && \

README.rst

@@ -30,19 +30,16 @@ Radon can compute:
 Requirements
 ------------
 
-Radon will run from **Python 2.7** to **Python 3.13** (except Python versions
-from 3.0 to 3.3) with a single code base and without the need of tools like
-2to3 or six. It can also run on **PyPy** without any problems (currently PyPy
-3.5 v7.3.1 is used in tests).
+Radon will run with **Python versions 3.3 to 3.13**; and through
+**PyPy** (currently PyPy 3.5 v7.3.1 is used in tests).
 
 Radon depends on as few packages as possible. Currently only `mando` is
 strictly required (for the CLI interface). `colorama` is also listed as a
 dependency but if Radon cannot import it, the output simply will not be
 colored.
 
 **Note**:
-**Python 2.6** was supported until version 1.5.0. Starting from version 2.0, it
-is not supported anymore.
+**Python2.7** support was dropped in v6.0.0.
 
 Installation
 ------------

codeclimate-radon

@@ -19,10 +19,8 @@ if os.path.exists("/config.json"):
 
         if config["config"].get("python_version"):
             version = config["config"].get("python_version")
-            if version == "2" or version == 2:
-                binstub = "radon2"
-            elif version != "3" and version != 3:
-                sys.exit("Invalid python_version; must be either 2 or 3")
+            if version != "3" and version != 3:
+                sys.exit("Invalid python_version; must be version 3")
         if config["config"].get("encoding"):
             encoding = config["config"].get("encoding")
             os.environ["RADONFILESENCODING"] = encoding

docs/conf.py

@@ -1,5 +1,3 @@
-# -*- coding: utf-8 -*-
-#
 # Radon documentation build configuration file, created by
 # sphinx-quickstart on Thu Oct 11 16:08:21 2012.
 #
@@ -46,9 +44,9 @@
 master_doc = 'index'
 
 # General information about the project.
-project = u'Radon'
+project = 'Radon'
 build_date = datetime.datetime.utcfromtimestamp(int(os.environ.get('SOURCE_DATE_EPOCH', time.time())))
-copyright = u'{0}, Michele Lacchia'.format('-'.join(map(str,
+copyright = '{0}, Michele Lacchia'.format('-'.join(map(str,
                                                         range(2012,
                                                               build_date.year + 1))))
 
@@ -193,8 +191,8 @@
 # Grouping the document tree into LaTeX files. List of tuples
 # (source start file, target name, title, author, documentclass [howto/manual]).
 latex_documents = [
-  ('index', 'Radon.tex', u'Radon Documentation',
-   u'Michele Lacchia', 'manual'),
+  ('index', 'Radon.tex', 'Radon Documentation',
+   'Michele Lacchia', 'manual'),
 ]
 
 # The name of an image file (relative to this directory) to place at the top of
@@ -223,8 +221,8 @@
 # One entry per manual page. List of tuples
 # (source start file, name, description, authors, manual section).
 man_pages = [
-    ('index', 'radon', u'Radon Documentation',
-     [u'Michele Lacchia'], 1)
+    ('index', 'radon', 'Radon Documentation',
+     ['Michele Lacchia'], 1)
 ]
 
 # If true, show URL addresses after external links.
@@ -237,8 +235,8 @@
 # (source start file, target name, title, author,
 #  dir menu entry, description, category)
 texinfo_documents = [
-  ('index', 'Radon', u'Radon Documentation',
-   u'Michele Lacchia', 'Radon', 'One line description of project.',
+  ('index', 'Radon', 'Radon Documentation',
+   'Michele Lacchia', 'Radon', 'One line description of project.',
    'Miscellaneous'),
 ]
 

pyproject.toml

@@ -17,10 +17,7 @@ colorama = [
 [tool.poetry.group.dev.dependencies]
 coverage = "*"
 coveralls = "*"
-pytest = [
-    {version = ">=2.7", markers = "python_version < \"3.0\""},
-    {version = ">5.0", markers = "python_version >= \"3.0\""}
-]
+pytest = ">5.0"
 pytest-mock = "*"
 argparse = "*"
 nbformat = "*"

radon/cli/__init__.py

@@ -1,5 +1,6 @@
 '''In this module the CLI interface is created.'''
 
+import configparser
 import inspect
 import os
 import sys
@@ -27,16 +28,11 @@
     RawHarvester,
 )
 
-if sys.version_info[0] == 2:
-    import ConfigParser as configparser
-else:
-    import configparser
-
 
 CONFIG_SECTION_NAME = 'radon'
 
 
-class FileConfig(object):
+class FileConfig:
     '''
     Yield default options by reading local configuration files.
     '''
@@ -319,7 +315,7 @@ def hal(
         log_result(harvester, json=json, xml=False, md=False, stream=stream)
 
 
-class Config(object):
+class Config:
     '''An object holding config values.'''
 
     def __init__(self, **kwargs):
@@ -347,12 +343,8 @@ def __eq__(self, other):
     @classmethod
     def from_function(cls, func):
         '''Construct a Config object from a function's defaults.'''
-        kwonlydefaults = {}
-        try:
-            argspec = inspect.getfullargspec(func)
-            kwonlydefaults = argspec.kwonlydefaults or {}
-        except AttributeError:  # pragma: no cover
-            argspec = inspect.getargspec(func)
+        argspec = inspect.getfullargspec(func)
+        kwonlydefaults = argspec.kwonlydefaults or {}
         args, _, _, defaults = argspec[:4]
         values = dict(zip(reversed(args), reversed(defaults or [])))
         values.update(kwonlydefaults)
@@ -420,7 +412,7 @@ def log_list(lst, *args, **kwargs):
 
 def log_error(msg, *args, **kwargs):
     '''Log an error message. Arguments are the same as log().'''
-    log('{0}{1}ERROR{2}: {3}'.format(BRIGHT, RED, RESET, msg), *args, **kwargs)
+    log('{}{}ERROR{}: {}'.format(BRIGHT, RED, RESET, msg), *args, **kwargs)
 
 
 @contextmanager

radon/cli/harvest.py

@@ -1,9 +1,8 @@
 '''This module holds the base Harvester class and all its subclassess.'''
 
 import collections
+import io
 import json
-import sys
-from builtins import super
 
 from radon.cli.colors import MI_RANKS, RANKS_COLORS, RESET
 from radon.cli.tools import (
@@ -26,11 +25,6 @@
 from radon.metrics import h_visit, mi_rank, mi_visit
 from radon.raw import analyze
 
-if sys.version_info[0] < 3:
-    from StringIO import StringIO
-else:
-    from io import StringIO
-
 try:
     import nbformat
 
@@ -39,7 +33,7 @@
     SUPPORTS_IPYNB = False
 
 
-class Harvester(object):
+class Harvester:
     '''Base class defining the interface of a Harvester object.
 
     A Harvester has the following lifecycle:
@@ -108,17 +102,17 @@ def run(self):
                             doc = "\n".join(cells)
                             yield (
                                 name,
-                                self.gobble(StringIO(strip_ipython(doc))),
+                                self.gobble(io.StringIO(strip_ipython(doc))),
                             )
 
                             if self.config.ipynb_cells:
                                 # Individual cells
                                 cellid = 0
                                 for source in cells:
                                     yield (
-                                        "{0}:[{1}]".format(name, cellid),
+                                        "{}:[{}]".format(name, cellid),
                                         self.gobble(
-                                            StringIO(strip_ipython(source))
+                                            io.StringIO(strip_ipython(source))
                                         ),
                                     )
                                     cellid += 1
@@ -374,7 +368,7 @@ def to_terminal(self):
             color = MI_RANKS[rank]
             to_show = ''
             if self.config.show:
-                to_show = ' ({0:.2f})'.format(mi['mi'])
+                to_show = ' ({:.2f})'.format(mi['mi'])
             yield '{0} - {1}{2}{3}{4}', (name, color, rank, to_show, RESET), {}