Add flake8 to linters and fix issues

diskcache/__init__.py

@@ -6,7 +6,9 @@
 
 """
 
-from .core import Cache, Disk, EmptyDirWarning, JSONDisk, UnknownFileWarning, Timeout
+from .core import (
+    Cache, Disk, EmptyDirWarning, JSONDisk, UnknownFileWarning, Timeout
+)
 from .core import DEFAULT_SETTINGS, ENOVAL, EVICTION_POLICY, UNKNOWN
 from .fanout import FanoutCache
 from .persistent import Deque, Index
@@ -37,7 +39,7 @@
 ]
 
 try:
-    from .djangocache import DjangoCache  # pylint: disable=wrong-import-position
+    from .djangocache import DjangoCache  # noqa
     __all__.append('DjangoCache')
 except Exception:  # pylint: disable=broad-except
     # Django not installed or not setup so ignore.

diskcache/core.py

@@ -14,23 +14,25 @@
 import pickletools
 import sqlite3
 import struct
-import sys
 import tempfile
 import threading
 import time
 import warnings
 import zlib
 
+
 def full_name(func):
     "Return full name of `func` by adding the module and function name."
     return func.__module__ + '.' + func.__qualname__
 
+
 try:
     WindowsError
 except NameError:
     class WindowsError(Exception):
         "Windows error place-holder on platforms without support."
 
+
 class Constant(tuple):
     "Pretty display of immutable constant."
     def __new__(cls, name):
@@ -39,6 +41,7 @@ def __new__(cls, name):
     def __repr__(self):
         return '%s' % self[0]
 
+
 DBNAME = 'cache.db'
 ENOVAL = Constant('ENOVAL')
 UNKNOWN = Constant('UNKNOWN')
@@ -133,7 +136,7 @@ def hash(self, key):
         if type_disk_key is sqlite3.Binary:
             return zlib.adler32(disk_key) & mask
         elif type_disk_key is str:
-            return zlib.adler32(disk_key.encode('utf-8')) & mask  # pylint: disable=no-member
+            return zlib.adler32(disk_key.encode('utf-8')) & mask  # noqa
         elif type_disk_key is int:
             return disk_key % mask
         else:
@@ -1056,7 +1059,9 @@ def incr(self, key, delta=1, default=0, retry=False):
                     raise KeyError(key)
 
                 value = default + delta
-                columns = (None, None) + self._disk.store(value, False, key=key)
+                columns = (
+                    (None, None) + self._disk.store(value, False, key=key)
+                )
                 self._row_insert(db_key, raw, now, columns)
                 self._cull(now, sql, cleanup)
                 return value
@@ -1068,7 +1073,9 @@ def incr(self, key, delta=1, default=0, retry=False):
                     raise KeyError(key)
 
                 value = default + delta
-                columns = (None, None) + self._disk.store(value, False, key=key)
+                columns = (
+                    (None, None) + self._disk.store(value, False, key=key)
+                )
                 self._row_update(rowid, now, columns)
                 self._cull(now, sql, cleanup)
                 cleanup(filename)
@@ -1184,7 +1191,7 @@ def get(self, key, default=None, read=False, expire_time=False, tag=False,
                     return default
 
                 (rowid, db_expire_time, db_tag,
-                     mode, filename, db_value), = rows
+                     mode, filename, db_value), = rows  # noqa: E127
 
                 try:
                     value = self._disk.fetch(mode, filename, db_value, read)
@@ -1269,7 +1276,7 @@ def __contains__(self, key):
         return bool(rows)
 
 
-    def pop(self, key, default=None, expire_time=False, tag=False, retry=False):
+    def pop(self, key, default=None, expire_time=False, tag=False, retry=False):  # noqa: E501
         """Remove corresponding item for `key` from cache and return value.
 
         If `key` is missing, return `default`.
@@ -2341,7 +2348,8 @@ def close(self):
 
     def __enter__(self):
         # Create connection in thread.
-        connection = self._con  # pylint: disable=unused-variable
+        # pylint: disable=unused-variable
+        connection = self._con  # noqa
         return self
 
 

diskcache/fanout.py

@@ -5,7 +5,6 @@
 import operator
 import os.path as op
 import sqlite3
-import sys
 import tempfile
 import time
 
@@ -290,7 +289,7 @@ def __contains__(self, key):
         return key in shard
 
 
-    def pop(self, key, default=None, expire_time=False, tag=False, retry=False):
+    def pop(self, key, default=None, expire_time=False, tag=False, retry=False):  # noqa: E501
         """Remove corresponding item for `key` from cache and return value.
 
         If `key` is missing, return `default`.

diskcache/persistent.py

@@ -197,8 +197,9 @@ def __setitem__(self, index, value):
         :raises IndexError: if index out of range
 
         """
-        set_value = lambda key: self._cache.__setitem__(key, value)
-        self._index(index, set_value)
+        def _set_value(key):
+            return self._cache.__setitem__(key, value)
+        self._index(index, _set_value)
 
 
     def __delitem__(self, index):

diskcache/recipes.py

@@ -6,7 +6,6 @@
 import math
 import os
 import random
-import sys
 import threading
 import time
 
@@ -82,7 +81,11 @@ def acquire(self):
         "Acquire lock using spin-lock algorithm."
         while True:
             added = self._cache.add(
-                self._key, None, expire=self._expire, tag=self._tag, retry=True,
+                self._key,
+                None,
+                expire=self._expire,
+                tag=self._tag,
+                retry=True,
             )
             if added:
                 break

tox.ini

@@ -9,7 +9,7 @@ deps=
     pytest-django
     pytest-xdist
 commands=python -m pytest
-setenv =
+setenv=
     DJANGO_SETTINGS_MODULE=tests.settings
     PYTHONPATH={toxinidir}
 
@@ -27,8 +27,17 @@ testpaths=docs diskcache tests
 [testenv:pylint]
 deps=
     django==2.2.*
+    flake8
     pylint
-commands=pylint diskcache
+commands=
+    flake8 diskcache
+    pylint diskcache
 
 [doc8]
 ignore=D000
+
+[flake8]
+ignore=
+    E124
+    E303
+    W503