migration: preserve ladder and rotation slice

app/tests/test_preservation_slice_ladder_rotation.py

@@ -0,0 +1,92 @@
+from __future__ import annotations
+
+import ast
+import hashlib
+import unittest
+from pathlib import Path
+
+
+APP_ROOT = Path(__file__).resolve().parents[1]
+ORIGINAL_ROOT = APP_ROOT.parent
+
+ROTATION_METHODS = {
+    "rotation_history",
+    "rotation_sector_members",
+}
+LADDER_ROTATION_BUILDERS = {
+    "_build_ladders",
+    "_build_sector_rotation",
+}
+
+
+def class_methods(path: Path, class_name: str) -> dict[str, str]:
+    tree = ast.parse(path.read_text(encoding="utf-8"), filename=str(path))
+    owner = next(
+        node
+        for node in tree.body
+        if isinstance(node, ast.ClassDef) and node.name == class_name
+    )
+    return {
+        node.name: ast.dump(node, include_attributes=False)
+        for node in owner.body
+        if isinstance(node, (ast.FunctionDef, ast.AsyncFunctionDef))
+    }
+
+
+def top_level_functions(path: Path) -> dict[str, str]:
+    tree = ast.parse(path.read_text(encoding="utf-8"), filename=str(path))
+    return {
+        node.name: ast.dump(node, include_attributes=False)
+        for node in tree.body
+        if isinstance(node, (ast.FunctionDef, ast.AsyncFunctionDef))
+        and node.name in LADDER_ROTATION_BUILDERS
+    }
+
+
+def sha256(path: Path) -> str:
+    return hashlib.sha256(path.read_bytes()).hexdigest()
+
+
+class LadderRotationSliceSourceEquivalenceTests(unittest.TestCase):
+    def test_rotation_service_methods_are_exact_original_ast(self) -> None:
+        original = class_methods(ORIGINAL_ROOT / "server.py", "DashboardService")
+        migrated = class_methods(
+            APP_ROOT / "backend" / "features" / "rotation" / "service.py",
+            "RotationServiceMixin",
+        )
+        self.assertEqual(set(migrated), ROTATION_METHODS)
+        for name in sorted(ROTATION_METHODS):
+            self.assertEqual(migrated[name], original[name], name)
+
+    def test_dashboard_service_no_longer_duplicates_rotation_methods(self) -> None:
+        remaining = class_methods(
+            APP_ROOT / "backend" / "application.py", "DashboardService"
+        )
+        self.assertTrue(ROTATION_METHODS.isdisjoint(remaining))
+
+    def test_ladder_and_rotation_builders_are_exact_original_ast(self) -> None:
+        self.assertEqual(
+            top_level_functions(ORIGINAL_ROOT / "tushare_client.py"),
+            top_level_functions(
+                APP_ROOT / "backend" / "data" / "providers" / "tushare_client.py"
+            ),
+        )
+
+    def test_api_and_frontend_assets_are_unchanged(self) -> None:
+        for relative in (
+            "config/api.config.json",
+            "static/index.html",
+            "static/app.js",
+            "static/styles.css",
+            "static/pages/ladder/page.js",
+            "static/pages/rotation/page.js",
+        ):
+            self.assertEqual(
+                sha256(APP_ROOT / relative),
+                sha256(ORIGINAL_ROOT / relative),
+                relative,
+            )
+
+
+if __name__ == "__main__":
+    unittest.main()