Refs #23919 -- Replaced six.reraise by raise

django/db/backends/mysql/base.py

@@ -4,23 +4,21 @@ MySQL database backend for Django.
 Requires mysqlclient: https://pypi.python.org/pypi/mysqlclient/
 """
 import re
-import sys
 
 from django.core.exceptions import ImproperlyConfigured
 from django.db import utils
 from django.db.backends import utils as backend_utils
 from django.db.backends.base.base import BaseDatabaseWrapper
-from django.utils import six
 from django.utils.functional import cached_property
 from django.utils.safestring import SafeBytes, SafeText
 
 try:
     import MySQLdb as Database
-except ImportError as e:
+except ImportError as err:
     raise ImproperlyConfigured(
-        'Error loading MySQLdb module: %s.\n'
-        'Did you install mysqlclient or MySQL-python?' % e
-    )
+        'Error loading MySQLdb module.\n'
+        'Did you install mysqlclient or MySQL-python?'
+    ) from err
 
 from MySQLdb.constants import CLIENT, FIELD_TYPE                # isort:skip
 from MySQLdb.converters import conversions                      # isort:skip
@@ -88,7 +86,7 @@ class CursorWrapper:
             # Map some error codes to IntegrityError, since they seem to be
             # misclassified and Django would prefer the more logical place.
             if e.args[0] in self.codes_for_integrityerror:
-                six.reraise(utils.IntegrityError, utils.IntegrityError(*tuple(e.args)), sys.exc_info()[2])
+                raise utils.IntegrityError(*tuple(e.args))
             raise
 
     def executemany(self, query, args):
@@ -98,7 +96,7 @@ class CursorWrapper:
             # Map some error codes to IntegrityError, since they seem to be
             # misclassified and Django would prefer the more logical place.
             if e.args[0] in self.codes_for_integrityerror:
-                six.reraise(utils.IntegrityError, utils.IntegrityError(*tuple(e.args)), sys.exc_info()[2])
+                raise utils.IntegrityError(*tuple(e.args))
             raise
 
     def __getattr__(self, attr):

django/db/backends/oracle/base.py

@@ -7,13 +7,11 @@ import datetime
 import decimal
 import os
 import platform
-import sys
 
 from django.conf import settings
 from django.core.exceptions import ImproperlyConfigured
 from django.db import utils
 from django.db.backends.base.base import BaseDatabaseWrapper
-from django.utils import six
 from django.utils.encoding import force_bytes, force_text
 from django.utils.functional import cached_property
 
@@ -261,7 +259,7 @@ class DatabaseWrapper(BaseDatabaseWrapper):
                 x = e.args[0]
                 if hasattr(x, 'code') and hasattr(x, 'message') \
                    and x.code == 2091 and 'ORA-02291' in x.message:
-                    six.reraise(utils.IntegrityError, utils.IntegrityError(*tuple(e.args)), sys.exc_info()[2])
+                    raise utils.IntegrityError(*tuple(e.args))
                 raise
 
     # Oracle doesn't support releasing savepoints. But we fake them when query

django/db/migrations/graph.py

@@ -1,10 +1,8 @@
-import sys
 import warnings
 from collections import deque
 from functools import total_ordering
 
 from django.db.migrations.state import ProjectState
-from django.utils import six
 from django.utils.datastructures import OrderedSet
 
 from .exceptions import CircularDependencyError, NodeNotFoundError
@@ -178,16 +176,12 @@ class MigrationGraph:
         replaced = set(replaced)
         try:
             replacement_node = self.node_map[replacement]
-        except KeyError as exc:
-            exc_value = NodeNotFoundError(
+        except KeyError as err:
+            raise NodeNotFoundError(
                 "Unable to find replacement node %r. It was either never added"
                 " to the migration graph, or has been removed." % (replacement, ),
                 replacement
-            )
-            exc_value.__cause__ = exc
-            if not hasattr(exc, '__traceback__'):
-                exc.__traceback__ = sys.exc_info()[2]
-            six.reraise(NodeNotFoundError, exc_value, sys.exc_info()[2])
+            ) from err
         for replaced_key in replaced:
             self.nodes.pop(replaced_key, None)
             replaced_node = self.node_map.pop(replaced_key, None)
@@ -218,16 +212,12 @@ class MigrationGraph:
         self.nodes.pop(replacement, None)
         try:
             replacement_node = self.node_map.pop(replacement)
-        except KeyError as exc:
-            exc_value = NodeNotFoundError(
+        except KeyError as err:
+            raise NodeNotFoundError(
                 "Unable to remove replacement node %r. It was either never added"
                 " to the migration graph, or has been removed already." % (replacement, ),
                 replacement
-            )
-            exc_value.__cause__ = exc
-            if not hasattr(exc, '__traceback__'):
-                exc.__traceback__ = sys.exc_info()[2]
-            six.reraise(NodeNotFoundError, exc_value, sys.exc_info()[2])
+            ) from err
         replaced_nodes = set()
         replaced_nodes_parents = set()
         for key in replaced:

django/db/migrations/loader.py

@@ -6,7 +6,6 @@ from django.apps import apps
 from django.conf import settings
 from django.db.migrations.graph import MigrationGraph
 from django.db.migrations.recorder import MigrationRecorder
-from django.utils import six
 
 from .exceptions import (
     AmbiguityError, BadMigrationError, InconsistentMigrationHistory,
@@ -256,7 +255,7 @@ class MigrationLoader:
                 is_replaced = any(candidate in self.graph.nodes for candidate in candidates)
                 if not is_replaced:
                     tries = ', '.join('%s.%s' % c for c in candidates)
-                    exc_value = NodeNotFoundError(
+                    raise NodeNotFoundError(
                         "Migration {0} depends on nonexistent node ('{1}', '{2}'). "
                         "Django tried to replace migration {1}.{2} with any of [{3}] "
                         "but wasn't able to because some of the replaced migrations "
@@ -264,11 +263,7 @@ class MigrationLoader:
                             exc.origin, exc.node[0], exc.node[1], tries
                         ),
                         exc.node
-                    )
-                    exc_value.__cause__ = exc
-                    if not hasattr(exc, '__traceback__'):
-                        exc.__traceback__ = sys.exc_info()[2]
-                    six.reraise(NodeNotFoundError, exc_value, sys.exc_info()[2])
+                    ) from exc
             raise exc
 
     def check_consistent_history(self, connection):

django/db/models/query.py

@@ -21,7 +21,7 @@ from django.db.models.fields import AutoField
 from django.db.models.functions import Trunc
 from django.db.models.query_utils import InvalidQuery, Q
 from django.db.models.sql.constants import CURSOR
-from django.utils import six, timezone
+from django.utils import timezone
 from django.utils.functional import cached_property, partition
 from django.utils.version import get_version
 
@@ -498,7 +498,7 @@ class QuerySet:
                 return self.get(**lookup), False
             except self.model.DoesNotExist:
                 pass
-            six.reraise(*exc_info)
+            raise exc_info[0](exc_info[1]).with_traceback(exc_info[2])
 
     def _extract_model_params(self, defaults, **kwargs):
         """

django/db/utils.py

@@ -5,7 +5,6 @@ from threading import local
 
 from django.conf import settings
 from django.core.exceptions import ImproperlyConfigured
-from django.utils import six
 from django.utils.functional import cached_property
 from django.utils.module_loading import import_string
 
@@ -90,7 +89,7 @@ class DatabaseErrorWrapper:
                 # the connection unusable.
                 if dj_exc_type not in (DataError, IntegrityError):
                     self.wrapper.errors_occurred = True
-                six.reraise(dj_exc_type, dj_exc_value, traceback)
+                raise dj_exc_value.with_traceback(traceback)
 
     def __call__(self, func):
         # Note that we are intentionally not using @wraps here for performance