Remove binding of captured exceptions when not used to reduce the chances of creating cycles

Author: pablogsal

Lib/asynchat.py

@@ -117,7 +117,7 @@ def handle_read(self):
             data = self.recv(self.ac_in_buffer_size)
         except BlockingIOError:
             return
-        except OSError as why:
+        except OSError:
             self.handle_error()
             return
 

Lib/asyncio/proactor_events.py

@@ -711,7 +711,7 @@ async def _sock_sendfile_native(self, sock, file, offset, count):
             raise exceptions.SendfileNotAvailableError("not a regular file")
         try:
             fsize = os.fstat(fileno).st_size
-        except OSError as err:
+        except OSError:
             raise exceptions.SendfileNotAvailableError("not a regular file")
         blocksize = count if count else fsize
         if not blocksize:

Lib/asyncio/unix_events.py

@@ -330,7 +330,7 @@ async def create_unix_server(
     async def _sock_sendfile_native(self, sock, file, offset, count):
         try:
             os.sendfile
-        except AttributeError as exc:
+        except AttributeError:
             raise exceptions.SendfileNotAvailableError(
                 "os.sendfile() is not available")
         try:
@@ -339,7 +339,7 @@ async def _sock_sendfile_native(self, sock, file, offset, count):
             raise exceptions.SendfileNotAvailableError("not a regular file")
         try:
             fsize = os.fstat(fileno).st_size
-        except OSError as err:
+        except OSError:
             raise exceptions.SendfileNotAvailableError("not a regular file")
         blocksize = count if count else fsize
         if not blocksize:

Lib/codeop.py

@@ -80,7 +80,7 @@ def _maybe_compile(compiler, source, filename, symbol):
 
     try:
         code = compiler(source, filename, symbol)
-    except SyntaxError as err:
+    except SyntaxError:
         pass
 
     try:

Lib/ctypes/util.py

@@ -302,7 +302,7 @@ def _findLib_ld(name):
                 res = re.search(expr, os.fsdecode(out))
                 if res:
                     result = res.group(0)
-            except Exception as e:
+            except Exception:
                 pass  # result will be None
             return result
 

Lib/enum.py

@@ -420,7 +420,7 @@ def _create_(cls, class_name, names, *, module=None, qualname=None, type=None, s
         if module is None:
             try:
                 module = sys._getframe(2).f_globals['__name__']
-            except (AttributeError, ValueError, KeyError) as exc:
+            except (AttributeError, ValueError, KeyError):
                 pass
         if module is None:
             _make_class_unpicklable(enum_class)

Lib/filecmp.py

@@ -156,12 +156,12 @@ def phase2(self): # Distinguish files, directories, funnies
             ok = 1
             try:
                 a_stat = os.stat(a_path)
-            except OSError as why:
+            except OSError:
                 # print('Can\'t stat', a_path, ':', why.args[1])
                 ok = 0
             try:
                 b_stat = os.stat(b_path)
-            except OSError as why:
+            except OSError:
                 # print('Can\'t stat', b_path, ':', why.args[1])
                 ok = 0
 

Lib/getpass.py

@@ -52,7 +52,7 @@ def unix_getpass(prompt='Password: ', stream=None):
             stack.enter_context(input)
             if not stream:
                 stream = input
-        except OSError as e:
+        except OSError:
             # If that fails, see if stdin can be controlled.
             stack.close()
             try:

Lib/importlib/abc.py

@@ -10,7 +10,7 @@
     _frozen_importlib = None
 try:
     import _frozen_importlib_external
-except ImportError as exc:
+except ImportError:
     _frozen_importlib_external = _bootstrap_external
 import abc
 import warnings

Lib/lib2to3/main.py

@@ -90,11 +90,11 @@ def write_file(self, new_text, filename, old_text, encoding):
             if os.path.lexists(backup):
                 try:
                     os.remove(backup)
-                except OSError as err:
+                except OSError:
                     self.log_message("Can't remove backup %s", backup)
             try:
                 os.rename(filename, backup)
-            except OSError as err:
+            except OSError:
                 self.log_message("Can't rename %s to %s", filename, backup)
         # Actually write the new file
         write = super(StdoutRefactoringTool, self).write_file

Lib/msilib/__init__.py

@@ -116,7 +116,7 @@ def add_data(db, table, values):
                 raise TypeError("Unsupported type %s" % field.__class__.__name__)
         try:
             v.Modify(MSIMODIFY_INSERT, r)
-        except Exception as e:
+        except Exception:
             raise MSIError("Could not insert "+repr(values)+" into "+table)
 
         r.ClearData()

Lib/multiprocessing/managers.py

@@ -248,7 +248,7 @@ def serve_client(self, conn):
                     try:
                         obj, exposed, gettypeid = \
                             self.id_to_local_proxy_obj[ident]
-                    except KeyError as second_ke:
+                    except KeyError:
                         raise ke
 
                 if methodname not in exposed:
@@ -296,7 +296,7 @@ def serve_client(self, conn):
             try:
                 try:
                     send(msg)
-                except Exception as e:
+                except Exception:
                     send(('#UNSERIALIZABLE', format_exc()))
             except Exception as e:
                 util.info('exception in thread serving %r',

Lib/multiprocessing/popen_fork.py

@@ -25,7 +25,7 @@ def poll(self, flag=os.WNOHANG):
         if self.returncode is None:
             try:
                 pid, sts = os.waitpid(self.pid, flag)
-            except OSError as e:
+            except OSError:
                 # Child process not yet created. See #1731717
                 # e.errno == errno.ECHILD == 10
                 return None

Lib/poplib.py

@@ -385,7 +385,7 @@ def _parsecap(line):
             for capline in rawcaps:
                 capnm, capargs = _parsecap(capline)
                 caps[capnm] = capargs
-        except error_proto as _err:
+        except error_proto:
             raise error_proto('-ERR CAPA not supported by server')
         return caps
 

Lib/test/pythoninfo.py

@@ -754,7 +754,7 @@ def collect_info(info):
     ):
         try:
             collect_func(info_add)
-        except Exception as exc:
+        except Exception:
             error = True
             print("ERROR: %s() failed" % (collect_func.__name__),
                   file=sys.stderr)

Lib/test/test_cgitb.py

@@ -31,7 +31,7 @@ def test_html(self):
     def test_text(self):
         try:
             raise ValueError("Hello World")
-        except ValueError as err:
+        except ValueError:
             text = cgitb.text(sys.exc_info())
             self.assertIn("ValueError", text)
             self.assertIn("Hello World", text)

Lib/test/test_class.py

@@ -529,7 +529,7 @@ class I:
             # In debug mode, printed XXX undetected error and
             #  raises AttributeError
             I()
-        except AttributeError as x:
+        except AttributeError:
             pass
         else:
             self.fail("attribute error for I.__init__ got masked")

Lib/test/test_codecs.py

@@ -11,7 +11,7 @@
 
 try:
     import _testcapi
-except ImportError as exc:
+except ImportError:
     _testcapi = None
 
 try:

Lib/test/test_decimal.py

@@ -5600,13 +5600,13 @@ def doit(ty):
                     args, kwds = mkargs(C, c_sig)
                     try:
                         getattr(c_type(9), attr)(*args, **kwds)
-                    except Exception as err:
+                    except Exception:
                         raise TestFailed("invalid signature for %s: %s %s" % (c_func, args, kwds))
 
                     args, kwds = mkargs(P, p_sig)
                     try:
                         getattr(p_type(9), attr)(*args, **kwds)
-                    except Exception as err:
+                    except Exception:
                         raise TestFailed("invalid signature for %s: %s %s" % (p_func, args, kwds))
 
         doit('Decimal')

Lib/test/test_ftplib.py

@@ -346,7 +346,7 @@ def _do_ssl_shutdown(self):
                 if err.args[0] in (ssl.SSL_ERROR_WANT_READ,
                                    ssl.SSL_ERROR_WANT_WRITE):
                     return
-            except OSError as err:
+            except OSError:
                 # Any "socket error" corresponds to a SSL_ERROR_SYSCALL return
                 # from OpenSSL's SSL_shutdown(), corresponding to a
                 # closed socket condition. See also:

Lib/test/test_sys_settrace.py

@@ -161,8 +161,8 @@ def raises():
 def test_raise():
     try:
         raises()
-    except Exception as exc:
-        x = 1
+    except Exception:
+        pass
 
 test_raise.events = [(0, 'call'),
                      (1, 'line'),
@@ -191,7 +191,7 @@ def _settrace_and_raise(tracefunc):
 def settrace_and_raise(tracefunc):
     try:
         _settrace_and_raise(tracefunc)
-    except RuntimeError as exc:
+    except RuntimeError:
         pass
 
 settrace_and_raise.events = [(2, 'exception'),

Lib/test/test_time.py

@@ -825,7 +825,7 @@ def convert_values(ns_timestamps):
                     try:
                         result = pytime_converter(value, time_rnd)
                         expected = expected_func(value)
-                    except Exception as exc:
+                    except Exception:
                         self.fail("Error on timestamp conversion: %s" % debug_info)
                     self.assertEqual(result,
                                      expected,

Lib/test/test_traceback.py

@@ -313,7 +313,7 @@ def f():
         with captured_output("stderr") as stderr_f:
             try:
                 f()
-            except RecursionError as exc:
+            except RecursionError:
                 render_exc()
             else:
                 self.fail("no recursion occurred")
@@ -360,7 +360,7 @@ def g(count=10):
         with captured_output("stderr") as stderr_g:
             try:
                 g()
-            except ValueError as exc:
+            except ValueError:
                 render_exc()
             else:
                 self.fail("no value error was raised")
@@ -396,7 +396,7 @@ def h(count=10):
         with captured_output("stderr") as stderr_h:
             try:
                 h()
-            except ValueError as exc:
+            except ValueError:
                 render_exc()
             else:
                 self.fail("no value error was raised")
@@ -424,7 +424,7 @@ def h(count=10):
         with captured_output("stderr") as stderr_g:
             try:
                 g(traceback._RECURSIVE_CUTOFF)
-            except ValueError as exc:
+            except ValueError:
                 render_exc()
             else:
                 self.fail("no error raised")
@@ -452,7 +452,7 @@ def h(count=10):
         with captured_output("stderr") as stderr_g:
             try:
                 g(traceback._RECURSIVE_CUTOFF + 1)
-            except ValueError as exc:
+            except ValueError:
                 render_exc()
             else:
                 self.fail("no error raised")

Lib/test/test_urllib2net.py

@@ -199,7 +199,7 @@ def test_sites_no_connection_close(self):
             try:
                 with urllib.request.urlopen(URL) as res:
                     pass
-            except ValueError as e:
+            except ValueError:
                 self.fail("urlopen failed for site not sending \
                            Connection:close")
             else:

Lib/test/test_uuid.py

@@ -471,7 +471,7 @@ def test_uuid1_eui64(self):
         # the value from too_large_getter above.
         try:
             self.uuid.uuid1(node=node)
-        except ValueError as e:
+        except ValueError:
             self.fail('uuid1 was given an invalid node ID')
 
     def test_uuid1(self):

Lib/unittest/case.py

@@ -712,7 +712,7 @@ def doClassCleanups(cls):
             function, args, kwargs = cls._class_cleanups.pop()
             try:
                 function(*args, **kwargs)
-            except Exception as exc:
+            except Exception:
                 cls.tearDown_exceptions.append(sys.exc_info())
 
     def __call__(self, *args, **kwds):

Lib/urllib/request.py

@@ -1778,7 +1778,7 @@ def retrieve(self, url, filename=None, reporthook=None, data=None):
                 hdrs = fp.info()
                 fp.close()
                 return url2pathname(_splithost(url1)[1]), hdrs
-            except OSError as msg:
+            except OSError:
                 pass
         fp = self.open(url, data)
         try:

Lib/xml/sax/__init__.py

@@ -78,7 +78,7 @@ def make_parser(parser_list=()):
     for parser_name in list(parser_list) + default_parser_list:
         try:
             return _create_parser(parser_name)
-        except ImportError as e:
+        except ImportError:
             import sys
             if parser_name in sys.modules:
                 # The parser module was found, but importing it