Replace db.Model with DeclarativeBase from SQLAlchemy for Flask-SQLAlchemy-Lite migration

tests/test_site/__init__.py

@@ -28,6 +28,7 @@ from flask.testing import FlaskCliRunner
 from flask_babel_js import BabelJS
 from flask_sqlalchemy import SQLAlchemy
 from flask_wtf import CSRFProtect
+from sqlalchemy.orm import DeclarativeBase
 
 bp: Blueprint = Blueprint("home", __name__)
 """The global blueprint."""
@@ -39,6 +40,10 @@ db: SQLAlchemy = SQLAlchemy()
 """The database instance."""
 
 
+class Base(DeclarativeBase):
+    """The base class for all models."""
+
+
 def create_app(is_testing: bool = False, is_skip_accounts: bool = False,
                is_skip_currencies: bool = False) -> Flask:
     """Create and configure the application.
@@ -99,6 +104,10 @@ def create_app(is_testing: bool = False, is_skip_accounts: bool = False,
             from accounting.utils.next_uri import append_next
             return redirect(append_next(url_for("auth.login-form")))
 
+        @property
+        def base(self) -> type[DeclarativeBase]:
+            return Base
+
         @property
         def cls(self) -> type[auth.User]:
             return auth.User
@@ -137,7 +146,7 @@ def init_db(app: Flask, is_skip_accounts: bool,
         otherwise.
     :return: None.
     """
-    db.create_all()
+    Base.metadata.create_all(db.engine)
     from .auth import User
     for username in ["viewer", "editor", "admin", "nobody"]:
         user: User | None = db.session.scalar(

tests/test_site/auth.py

@@ -24,13 +24,13 @@ from flask import Blueprint, render_template, Flask, redirect, url_for, \
     session, request, g, Response, abort
 from sqlalchemy.orm import Mapped, mapped_column
 
-from . import db
+from . import db, Base
 
 bp: Blueprint = Blueprint("auth", __name__, url_prefix="/")
 """The authentication blueprint."""
 
 
-class User(db.Model):
+class User(Base):
     """A user."""
     __tablename__ = "users"
     """The table name."""