chore: bootstrap housing research platform

tests/test_indicators.py

@@ -0,0 +1,36 @@
+from __future__ import annotations
+
+import tempfile
+import unittest
+from pathlib import Path
+
+from shanghai_housing.db import connect, load_sample_data
+from shanghai_housing.indicators import compute_area_scores, previous_month
+
+
+class IndicatorTests(unittest.TestCase):
+    def test_previous_month_handles_year_boundary(self) -> None:
+        self.assertEqual(previous_month("2026-01"), "2025-12")
+        self.assertEqual(previous_month("2026-05"), "2026-04")
+
+    def test_area_scores_are_bounded_and_sorted(self) -> None:
+        with tempfile.TemporaryDirectory() as tmpdir:
+            db_path = Path(tmpdir) / "test.sqlite"
+            load_sample_data(db_path)
+            with connect(db_path) as conn:
+                scores = compute_area_scores(conn, "2026-05")
+
+        self.assertEqual(len(scores), 5)
+        self.assertEqual(
+            [score.investment_score for score in scores],
+            sorted([score.investment_score for score in scores], reverse=True),
+        )
+        for score in scores:
+            self.assertGreaterEqual(score.investment_score, 0)
+            self.assertLessEqual(score.investment_score, 100)
+            self.assertGreaterEqual(score.supply_risk_score, 0)
+            self.assertLessEqual(score.supply_risk_score, 100)
+
+
+if __name__ == "__main__":
+    unittest.main()