Run flake8 through CI

Author: snoack

.travis.yml

@@ -27,6 +27,9 @@ matrix:
       dist: trusty
       env:
         - DEPS="$LEGACY_DEPS"
+    - python: 3.7
+      env:
+        - TOXENV=flake8
 
 install:
   - pip install $DEPS

goto.py

@@ -16,17 +16,17 @@ def __init__(self):
         code = (lambda: x if x else y).__code__.co_code
         opcode, oparg = struct.unpack_from('BB', code, 2)
 
-        # Starting with Python 3.6, the bytecode format has been changed to use
+        # Starting with Python 3.6, the bytecode format has changed, using
         # 16-bit words (8-bit opcode + 8-bit argument) for each instruction,
-        # as opposed to previously 24-bit (8-bit opcode + 16-bit argument) for
-        # instructions that expect an argument or just 8-bit for those that don't.
+        # as opposed to previously 24 bit (8-bit opcode + 16-bit argument)
+        # for instructions that expect an argument and otherwise 8 bit.
         # https://bugs.python.org/issue26647
         if dis.opname[opcode] == 'POP_JUMP_IF_FALSE':
             self.argument = struct.Struct('B')
             self.have_argument = 0
-            # As of Python 3.6, jump targets are still addressed by their byte
-            # unit. This, however, is matter to change, so that jump targets,
-            # in the future, will refer to the code unit (address in bytes / 2).
+            # As of Python 3.6, jump targets are still addressed by their
+            # byte unit. This is matter to change, so that jump targets,
+            # in the future might refer to code units (address in bytes / 2).
             # https://bugs.python.org/issue26647
             self.jump_unit = 8 // oparg
         else:
@@ -155,8 +155,9 @@ def _find_labels_and_gotos(code):
                 name = code.co_names[oparg1]
                 if name == 'label':
                     if oparg2 in labels:
-                        co_name = code.co_names[oparg2]
-                        raise SyntaxError('Ambiguous label {0!r}'.format(co_name))
+                        raise SyntaxError('Ambiguous label {0!r}'.format(
+                            code.co_names[oparg2]
+                        ))
                     labels[oparg2] = (offset1,
                                       offset4,
                                       tuple(block_stack))
@@ -196,7 +197,9 @@ def _patch_code(code):
         try:
             _, target, target_stack = labels[label]
         except KeyError:
-            raise SyntaxError('Unknown label {0!r}'.format(code.co_names[label]))
+            raise SyntaxError('Unknown label {0!r}'.format(
+                code.co_names[label]
+            ))
 
         target_depth = len(target_stack)
         if origin_stack[:target_depth] != target_stack:

setup.py

@@ -8,7 +8,8 @@
     name='goto-statement',
     version='1.2',
     url='https://github.com/snoack/python-goto/',
-    description='A function decorator, that rewrites the bytecode, to enable goto in Python',
+    description='A function decorator that rewrites the bytecode, '
+                'enabling goto in Python',
     long_description=long_description,
     long_description_content_type='text/markdown',
     py_modules=['goto'],

test_goto.py

@@ -1,4 +1,3 @@
-import sys
 import pytest
 from goto import with_goto
 
@@ -137,21 +136,21 @@ def func():
         try:
             rv = None
             goto .end
-        except:
+        except Exception:
             rv = 'except'
         finally:
             rv = 'finally'
         label .end
         return rv
 
-    assert func() == None
+    assert func() is None
 
 
 def test_jump_into_try_block():
     def func():
         try:
             label .block
-        except:
+        except Exception:
             pass
         goto .block
 

tox.ini

@@ -1,11 +1,19 @@
 [tox]
-envlist = py26,py27,py32,py33,py34,py35,py36,py37,pypy,pypy3
+envlist = py26,py27,py32,py33,py34,py35,py36,py37,pypy,pypy3,flake8
 skip_missing_interpreters = true
 
 [testenv]
 deps = pytest
 commands = py.test
 
+[flake8]
+extend-ignore = F821
+
+[testenv:flake8]
+skip_install = true
+deps = flake8
+commands = flake8
+
 [legacy]
 deps =
   py<1.5