Fix sqlite create/drop index (#379)

* Update add/drop index template for sqlite

* tests: add sqlite migrate/upgrade command test

* tests: add timeout for sqlite migrate command test

* tests: add test cases for add/drop unique field for sqlite

* fix: sqlite failed to add unique field

aerich/ddl/__init__.py

@@ -3,6 +3,7 @@ from typing import Any, List, Type, cast
 
 from tortoise import BaseDBAsyncClient, Model
 from tortoise.backends.base.schema_generator import BaseSchemaGenerator
+from tortoise.backends.sqlite.schema_generator import SqliteSchemaGenerator
 
 from aerich.utils import is_default_function
 
@@ -122,7 +123,12 @@ class BaseDDL:
             unique = ""
             template = self._MODIFY_COLUMN_TEMPLATE
         else:
-            unique = "UNIQUE" if field_describe.get("unique") else ""
+            # sqlite does not support alter table to add unique column
+            unique = (
+                "UNIQUE"
+                if field_describe.get("unique") and self.DIALECT != SqliteSchemaGenerator.DIALECT
+                else ""
+            )
             template = self._ADD_COLUMN_TEMPLATE
         return template.format(
             table_name=db_table,

aerich/ddl/sqlite/__init__.py

@@ -10,6 +10,8 @@ from aerich.exceptions import NotSupportError
 class SqliteDDL(BaseDDL):
     schema_generator_cls = SqliteSchemaGenerator
     DIALECT = SqliteSchemaGenerator.DIALECT
+    _ADD_INDEX_TEMPLATE = 'CREATE {unique}INDEX "{index_name}" ON "{table_name}" ({column_names})'
+    _DROP_INDEX_TEMPLATE = 'DROP INDEX IF EXISTS "{index_name}"'
 
     def modify_column(self, model: "Type[Model]", field_object: dict, is_pk: bool = True):
         raise NotSupportError("Modify column is unsupported in SQLite.")