Fix business compare history, search, sampling and exports

tests/test_biz_state_compare_export.py

@@ -0,0 +1,87 @@
+"""Export must page lazily, keep tied sequence rows, and produce valid UTF-8 CSV."""
+
+from __future__ import annotations
+
+import csv
+import io
+import unittest
+import zipfile
+from unittest.mock import patch
+
+from sqlalchemy import create_engine, event
+from sqlalchemy.orm import Session
+
+from netx_api.biz_state.compare_service import _iter_sheet_diffs, export_run_zip
+from netx_api.db import Base
+from netx_api.models import BizCompareDiff, BizCompareRun
+
+
+class CompareExportTests(unittest.TestCase):
+    def setUp(self):
+        self.engine = create_engine("sqlite+pysqlite:///:memory:")
+        Base.metadata.create_all(self.engine)
+        self.db = Session(self.engine)
+        self.sheet = {"sheet_id": "sheet", "metric_id": "test", "key_fields": ["id"],
+                      "compare_fields": ["note"], "display_fields": ["id", "note"],
+                      "summary": {"unchanged": 7}, "status": "done"}
+        self.run = BizCompareRun(id="run", metric_id="test", status="success",
+                                 summary_json={"sheets": [self.sheet]})
+        self.db.add(self.run)
+        for seq, ids in ((0, "cba"), (1, "ed"), (2, "gf")):
+            for rid in ids:
+                note = '中文, "quoted"\nsecond line'
+                self.db.add(BizCompareDiff(id=rid, run_id="run", metric_id="sheet", seq=seq,
+                                           kind="unchanged", key_json={"id": rid},
+                                           before_json={"id": rid, "note": note},
+                                           after_json={"id": rid, "note": note}))
+        self.db.commit()
+
+    def tearDown(self):
+        self.db.close()
+        self.engine.dispose()
+
+    def test_cursor_handles_tied_sequence_numbers_across_chunks(self):
+        statements = []
+        def record(_conn, _cursor, statement, _parameters, _context, _executemany):
+            if "ORDER BY biz_compare_diff.seq" in statement:
+                statements.append(statement)
+        event.listen(self.engine, "before_cursor_execute", record)
+        with patch("netx_api.biz_state.compare_service._DIFF_CHUNK", 2):
+            iterator = _iter_sheet_diffs(self.db, "run", "sheet")
+            self.assertEqual(statements, [])
+            self.assertEqual(next(iterator)["key"]["id"], "a")
+            self.assertEqual(next(iterator)["key"]["id"], "b")
+            self.assertEqual(len(statements), 1, "do not load the next chunk early")
+            self.assertEqual([d["key"]["id"] for d in iterator], list("cdefg"))
+        self.assertEqual(len(statements), 4)
+        self.assertTrue(all("biz_compare_diff.seq >" in q and "biz_compare_diff.id >" in q
+                            for q in statements[1:]))
+
+    def test_export_csv_escapes_unicode_quotes_commas_and_newlines(self):
+        with patch("netx_api.biz_state.compare_service._DIFF_CHUNK", 2):
+            archive_bytes = export_run_zip(self.db, "run")
+        with zipfile.ZipFile(io.BytesIO(archive_bytes)) as archive:
+            payload = archive.read("tables/sheet.csv")
+            self.assertTrue(payload.startswith(b"\xef\xbb\xbf"))
+            rows = list(csv.DictReader(io.StringIO(payload.decode("utf-8-sig"))))
+            self.assertEqual([r["id"] for r in rows], list("abcdefg"))
+            self.assertTrue(all(r["note__pre"] == '中文, "quoted"\nsecond line' for r in rows))
+            self.assertTrue(all(r["note__pre"] == r["note__post"] for r in rows))
+
+    def test_other_sheets_do_not_leak_into_export(self):
+        self.db.add(BizCompareDiff(id="other", run_id="run", metric_id="another", seq=0,
+                                   kind="added", key_json={"id": "other"}, after_json={"note": "other"}))
+        self.db.commit()
+        with patch("netx_api.biz_state.compare_service._DIFF_CHUNK", 2):
+            self.assertEqual([d["key"]["id"] for d in _iter_sheet_diffs(self.db, "run", "sheet")], list("abcdefg"))
+
+    def test_legacy_inline_and_empty_exports(self):
+        self.db.query(BizCompareDiff).delete()
+        inline = {"kind": "added", "key": {"id": "legacy"}, "after": {"note": "value"}}
+        self.run.summary_json = {"sheets": [{**self.sheet, "diffs": [inline]}]}
+        self.db.commit()
+        self.assertEqual(list(_iter_sheet_diffs(self.db, "run", "sheet")), [inline])
+        self.run.summary_json = {"sheets": [self.sheet]}
+        self.db.commit()
+        with zipfile.ZipFile(io.BytesIO(export_run_zip(self.db, "run"))) as archive:
+            self.assertEqual(archive.read("tables/sheet.csv").decode("utf-8-sig"), "kind,id,note__pre,note__post\n")