PEP8 swift cleanup

The None, True, and False values are singletons.

All variable *comparisons* to singletons should use 'is' or 'is not'.
All variable *evaluations* to boolean should use 'if' or 'if not'.
All Object type comparisons should use isinstance()
instead of comparing types directly.

Change-Id: I47863c4862791022670619f19b8bc15d8a93fd81

swift/common/utils.py

@@ -852,7 +852,7 @@ def write_pickle(obj, dest, tmp=None, pickle_protocol=0):
     :param tmp: path to tmp to use, defaults to None
     :param pickle_protocol: protocol to pickle the obj with, defaults to 0
     """
-    if tmp == None:
+    if tmp is None:
         tmp = os.path.dirname(dest)
     fd, tmppath = mkstemp(dir=tmp, suffix='.tmp')
     with os.fdopen(fd, 'wb') as fo:

swift/obj/server.py

@@ -644,7 +644,7 @@ class ObjectController(object):
                 file.metadata['ETag'] not in request.if_match:
             file.close()
             return HTTPPreconditionFailed(request=request)
-        if request.headers.get('if-none-match') != None:
+        if request.headers.get('if-none-match') is not None:
             if file.metadata['ETag'] in request.if_none_match:
                 resp = HTTPNotModified(request=request)
                 resp.etag = file.metadata['ETag']

test/functional/swift.py

@@ -321,7 +321,7 @@ class Account(Base):
         format = parms.get('format', None)
         if format not in [None, 'json', 'xml']:
             raise RequestError('Invalid format: %s' % format)
-        if format == None and parms.has_key('format'):
+        if format is None and parms.has_key('format'):
             del parms['format']
 
         status = self.conn.make_request('GET', self.path, hdrs=hdrs,
@@ -410,7 +410,7 @@ class Container(Base):
         format = parms.get('format', None)
         if format not in [None, 'json', 'xml']:
             raise RequestError('Invalid format: %s' % format)
-        if format == None and parms.has_key('format'):
+        if format is None and parms.has_key('format'):
             del parms['format']
 
         status = self.conn.make_request('GET', self.path, hdrs=hdrs,
@@ -591,7 +591,7 @@ class File(Base):
 
     @classmethod
     def random_data(cls, size=None):
-        if size == None:
+        if size is None:
             size = random.randint(1, 32768)
         fd = open('/dev/urandom', 'r')
         data = fd.read(size)
@@ -674,9 +674,9 @@ class File(Base):
         return True
 
     def chunked_write(self, data=None, hdrs={}, parms={}, cfg={}):
-        if data != None and self.chunked_write_in_progress:
+        if data is not None and self.chunked_write_in_progress:
             self.conn.put_data(data, True)
-        elif data != None:
+        elif data is not None:
             self.chunked_write_in_progress = True
 
             headers = self.make_headers(cfg=cfg)

test/functional/tests.py

@@ -81,7 +81,7 @@ class Utils:
 
     @classmethod
     def create_utf8_name(cls, length=None):
-        if length == None:
+        if length is None:
             length = 15
         else:
             length = int(length)
@@ -271,7 +271,7 @@ class TestAccount(Base):
             containers = self.env.account.containers(
                 parms={'format':format,'marker':containers[-1]})
             self.assertEquals(len(containers), 0)
-            if format == None:
+            if format is None:
                 self.assert_status(204)
             else:
                 self.assert_status(200)
@@ -320,7 +320,7 @@ class TestAccountNoContainers(Base):
             self.assert_(not self.env.account.containers(
                 parms={'format':format}))
 
-            if format == None:
+            if format is None:
                 self.assert_status(204)
             else:
                 self.assert_status(200)
@@ -529,7 +529,7 @@ class TestContainer(Base):
                 parms={'format':format,'marker':files[-1]})
             self.assertEquals(len(files), 0)
 
-            if format == None:
+            if format is None:
                 self.assert_status(204)
             else:
                 self.assert_status(200)

test/unit/__init__.py

@@ -145,6 +145,6 @@ class MockTrue(object):
     def __repr__(*args, **kwargs):
         return repr(True)
     def __eq__(self, other):
-        return other == True
+        return other is True
     def __ne__(self, other):
-        return other != True
+        return other is not True

test/unit/common/test_db.py

@@ -607,7 +607,7 @@ class TestContainerBroker(unittest.TestCase):
                 raise Exception('OMG')
         except Exception:
             pass
-        self.assert_(broker.conn == None)
+        self.assert_(broker.conn is None)
 
     def test_empty(self):
         """ Test swift.common.db.ContainerBroker.empty """
@@ -1535,7 +1535,7 @@ class TestAccountBroker(unittest.TestCase):
                 raise Exception('OMG')
         except Exception:
             pass
-        self.assert_(broker.conn == None)
+        self.assert_(broker.conn is None)
 
     def test_empty(self):
         """ Test swift.common.db.AccountBroker.empty """

test/unit/proxy/test_server.py

@@ -483,7 +483,7 @@ class TestController(unittest.TestCase):
             cache_key = proxy_server.get_container_memcache_key(self.account,
                 self.container)
             cache_value = self.memcache.get(cache_key)
-            self.assertEquals(dict, type(cache_value))
+            self.assertTrue(isinstance(cache_value, dict))
             self.assertEquals(200, cache_value.get('status'))
 
             proxy_server.http_connect = fake_http_connect()
@@ -506,7 +506,7 @@ class TestController(unittest.TestCase):
             cache_key = proxy_server.get_container_memcache_key(self.account,
                 self.container)
             cache_value = self.memcache.get(cache_key)
-            self.assertEquals(dict, type(cache_value))
+            self.assertTrue(isinstance(cache_value, dict))
             self.assertEquals(404, cache_value.get('status'))
 
             proxy_server.http_connect = fake_http_connect()