migration: prove standalone maintenance and correct visual evidence

app/tests/test_maintenance_tools.py

@@ -3,11 +3,16 @@ from __future__ import annotations
 import json
 import subprocess
 import sys
+import tempfile
 import unittest
 from pathlib import Path
 
 from tools.build_api_registry import build as build_api_registry
-from tools.build_architecture_inventory import build as build_architecture_inventory
+from tools.build_architecture_inventory import (
+    build as build_architecture_inventory,
+    source_metrics,
+)
+from tools.verify_baseline import python_test_command
 
 
 ROOT = Path(__file__).resolve().parents[1]
@@ -34,6 +39,22 @@ class MaintenanceToolTests(unittest.TestCase):
         self.assertIn("stop_e2e_server(server)", source)
         self.assertNotIn('"static/app.js"', source)
 
+    def test_standalone_verifier_excludes_only_migration_comparison_modules(self) -> None:
+        repository_command = python_test_command(preservation_baseline=True)
+        standalone_command = python_test_command(preservation_baseline=False)
+        self.assertIn("discover", repository_command)
+        self.assertTrue(any(item == "tests.test_frontend_contract" for item in standalone_command))
+        self.assertFalse(any("test_preservation_" in item for item in standalone_command))
+
+    def test_architecture_metrics_are_independent_of_checkout_line_endings(self) -> None:
+        with tempfile.TemporaryDirectory() as directory:
+            root = Path(directory)
+            lf = root / "lf.js"
+            crlf = root / "crlf.js"
+            lf.write_bytes(b"const a = 1;\nconst b = 2;\n")
+            crlf.write_bytes(b"const a = 1;\r\nconst b = 2;\r\n")
+            self.assertEqual(source_metrics(lf), source_metrics(crlf))
+
     def test_every_tool_has_a_non_mutating_help_path(self) -> None:
         for path in sorted((ROOT / "tools").glob("*.py")):
             if path.name.startswith("_"):