From 9d8e9e882defe3c72a50fdd98bf01681a340b361 Mon Sep 17 00:00:00 2001
From: shimizukawa <shimizukawa@gmail.com>
Date: Sun, 16 Oct 2022 20:29:54 +0000
Subject: [PATCH] Drop Django-2.2 support #83

---
 django_redshift_backend/__init__.py |  2 +-
 django_redshift_backend/base.py     | 23 ++++++-----------------
 tests/test_redshift_backend.py      | 14 +++-----------
 3 files changed, 10 insertions(+), 29 deletions(-)

diff --git a/django_redshift_backend/__init__.py b/django_redshift_backend/__init__.py
index 3a419b8..8abb12d 100644
--- a/django_redshift_backend/__init__.py
+++ b/django_redshift_backend/__init__.py
@@ -5,7 +5,7 @@
     except PackageNotFoundError:
         # package is not installed
         pass
-except ImportError:  # py36, py37
+except ImportError:  # py37
     from pkg_resources import get_distribution, DistributionNotFound
     try:
         __version__ = get_distribution(__name__).version
diff --git a/django_redshift_backend/base.py b/django_redshift_backend/base.py
index 3e18b23..df6cf2b 100644
--- a/django_redshift_backend/base.py
+++ b/django_redshift_backend/base.py
@@ -144,10 +144,6 @@ class DatabaseSchemaEditor(BasePGDatabaseSchemaEditor):
     sql_create_table = "CREATE TABLE %(table)s (%(definition)s) %(options)s"
     sql_delete_fk = "ALTER TABLE %(table)s DROP CONSTRAINT %(name)s"
 
-    if django.VERSION < (3,):
-        # to remove "USING %(column)s::%(type)s"
-        sql_alter_column_type = "ALTER COLUMN %(column)s TYPE %(type)s"
-
     @property
     def multiply_varchar_length(self):
         return int(getattr(settings, "REDSHIFT_VARCHAR_LENGTH_MULTIPLIER", 1))
@@ -878,7 +874,7 @@ def _create_unique_sql(
         self, model, fields, name=None, condition=None, deferrable=None,
         include=None, opclasses=None, expressions=None,
     ):
-        if django.VERSION >= (4,):
+        if django.VERSION >= (4,):  # dj40 support
             return super()._create_unique_sql(
                 model, fields, name=name, condition=condition, deferrable=deferrable,
                 include=include, opclasses=opclasses, expressions=expressions
@@ -892,13 +888,8 @@ def _create_unique_sql(
                 model, columns, name=name, condition=condition, deferrable=deferrable,
                 include=include, opclasses=opclasses,
             )
-        else:  # dj32, dj22 support
-            columns = [
-                field.column if hasattr(field, 'column') else field
-                for field in fields
-            ]
-            return super()._create_unique_sql(
-                model, columns, name=name, condition=condition)
+        else:  # dj22 or earlier are not supported
+            raise NotImplementedError
 
 
 redshift_data_types = {
@@ -947,15 +938,13 @@ def get_table_description(self, cursor, table_name):
         # field_map = {line[0]: line[1:] for line in cursor.fetchall()}
         field_map = {}
         for column_name, is_nullable, column_default in cursor.fetchall():
-            _field_map = {
+            field_map[column_name] = {
                 'null_ok': is_nullable,
                 'default': column_default,
-            }
-            if django.VERSION >= (3, 2):
                 # Redshift doesn't support user-defined collation
                 # https://docs.aws.amazon.com/redshift/latest/dg/c_collation_sequences.html
-                _field_map['collation'] = None
-            field_map[column_name] = _field_map
+                'collation': None,
+            }
         cursor.execute(
             "SELECT * FROM %s LIMIT 1" % self.connection.ops.quote_name(table_name)
         )
diff --git a/tests/test_redshift_backend.py b/tests/test_redshift_backend.py
index 1da0148..3b49adf 100644
--- a/tests/test_redshift_backend.py
+++ b/tests/test_redshift_backend.py
@@ -3,7 +3,6 @@
 import os
 import unittest
 
-import django
 from django.db import connections
 from django.db.utils import NotSupportedError
 from django.core.management.color import no_style
@@ -158,16 +157,9 @@ def test_create_table_meta_keys(self):
                         reason='to run, TEST_WITH_POSTGRES=1 tox')
     def test_sqlmigrate(self):
         from django.db import connection
-
-        if django.VERSION < (3, 0):  # for dj22
-            from django.db.migrations.executor import MigrationExecutor
-            executor = MigrationExecutor(connection)
-            loader = executor.loader
-            collect_sql = executor.collect_sql
-        else:
-            from django.db.migrations.loader import MigrationLoader
-            loader = MigrationLoader(connection)
-            collect_sql = loader.collect_sql
+        from django.db.migrations.loader import MigrationLoader
+        loader = MigrationLoader(connection)
+        collect_sql = loader.collect_sql
 
         app_label, migration_name = 'testapp', '0001'
         migration = loader.get_migration_by_prefix(app_label, migration_name)