From 9b07a0f935108a81a8800845e35c40eff088a190 Mon Sep 17 00:00:00 2001
From: lekss361 <alexey.kondratev@balance-pl.ru>
Date: Sun, 24 May 2026 18:50:04 +0300
Subject: [PATCH] =?UTF-8?q?fix(yandex-valuation):=20relax=20area=20regex?=
 =?UTF-8?q?=20lookbehind=20(2-=D0=BA=D0=BE=D0=BC=D0=BD=20regression)?=
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PR #541 lookbehind (?<![\d.,]) was too strict — re-sweep showed
area_filled dropped from 48% to 8.8% with all 2-комн rooms losing
area (chunked text often has a price-per-m2 digit immediately before
the room's area token).

Loosen to (?<!\d) (only digit-adjacency blocked, comma/dot fine)
and tighten quantifier to \d{2,4} (min 2 digits blocks sub-fragments
like '2,2' inside '52,2'). Year-concat 20244,6 still rejected because
greedy '\d{2,4}' grabs '2024', then [.,] separator doesn't follow.
---
 .../app/services/scrapers/yandex_valuation.py | 10 +++---
 .../backend/tests/test_yandex_valuation.py    | 34 +++++++++++++++++++
 2 files changed, 40 insertions(+), 4 deletions(-)

diff --git a/tradein-mvp/backend/app/services/scrapers/yandex_valuation.py b/tradein-mvp/backend/app/services/scrapers/yandex_valuation.py
index 10fc3316..09b89f19 100644
--- a/tradein-mvp/backend/app/services/scrapers/yandex_valuation.py
+++ b/tradein-mvp/backend/app/services/scrapers/yandex_valuation.py
@@ -120,10 +120,12 @@ RE_FLOORS = re.compile(r"(\d+)\s+этажей", re.IGNORECASE)
 RE_CEILING = re.compile(r"([\d,]+)\s*м\s+потолки", re.IGNORECASE)
 RE_TOTAL_OBJECTS = re.compile(r"(\d+)\s+объект", re.IGNORECASE)
 
-# Negative lookbehind on digit/comma/dot prevents matching the trailing digits of
-# adjacent tokens — e.g. publish year "2024" right before "42,6 м²" must NOT
-# yield "20242,6". Cap whole-number part at 4 digits and decimal part at 2.
-RE_ITEM_AREA = re.compile(r"(?<![\d.,])(\d{1,4}(?:[.,]\d{1,2})?)\s*м²")
+# Lookbehind blocks digit-only adjacency (rejects year-concat like '20244,6')
+# while still allowing tokens preceded by punctuation/letter. Min 2 digits
+# rejects sub-fragments like '2,2' that come from inside '52,2'. Max 4 digits
+# whole part catches obvious junk (penthouse extremes are <500 m² in practice;
+# sanity cap from PR #538 backs this up).
+RE_ITEM_AREA = re.compile(r"(?<!\d)(\d{2,4}(?:[.,]\d{1,2})?)\s*м²")
 RE_ITEM_ROOMS = re.compile(r"(\d+)\s*-\s*комнатн", re.IGNORECASE)
 RE_ITEM_STUDIO = re.compile(r"студи[яюй]", re.IGNORECASE)
 RE_ITEM_FLOOR = re.compile(r"(\d+)\s*этаж", re.IGNORECASE)
diff --git a/tradein-mvp/backend/tests/test_yandex_valuation.py b/tradein-mvp/backend/tests/test_yandex_valuation.py
index 316da0ee..a727d62b 100644
--- a/tradein-mvp/backend/tests/test_yandex_valuation.py
+++ b/tradein-mvp/backend/tests/test_yandex_valuation.py
@@ -448,3 +448,37 @@ def test_single_date_is_publish_only():
 
     assert item.publish_date == _d(2024, 3, 15)
     assert item.removed_date is None
+
+
+def test_area_regex_two_komn_chunk():
+    """2-комн chunks were 100% rejected by PR #541 lookbehind. Real bug from
+    Базовый 52 sweep: 'rooms=2 → area_m2 is None' for every 2-комн row.
+    """
+    # Approximate the chunked text Yandex emits for a 2-room item
+    text = "8 000 000 ₽ за м²2-комнатная 52,2 м²  5 этаж  10.05.2024  8 000 000 ₽  В продаже"
+    item = YandexValuationScraper._parse_item_text(text)
+    assert item is not None
+    assert item.area_m2 == 52.2, (
+        f"2-комн area must parse despite preceding tokens, got {item.area_m2}"
+    )
+
+
+def test_area_regex_still_blocks_year_concat():
+    """The relaxed regex must still reject year+area concat."""
+    # '2024' directly fused to '42,6 м²' as can happen after DOM strip
+    text = "квартира 202442,6 м²  3 этаж  10.05.2024  9 000 000 ₽  В продаже"
+    item = YandexValuationScraper._parse_item_text(text)
+    # The '202442,6' token: a `\\d{2,4}` greedy match starting at first '2'
+    # gives '2024', then needs '[.,]\\d{1,2}' but '4' follows → no match.
+    # Any internal start is blocked by `(?<!\\d)`. So no area parsed.
+    assert item is None or item.area_m2 is None
+
+
+def test_area_regex_still_blocks_subfragment():
+    """Min 2 digits blocks '2,2' fragment from inside '52,2'."""
+    # Pure single-digit start without preceding non-digit context
+    text = "квартира ,2,2 м²  10.05.2024  5 000 000 ₽  В продаже"
+    item = YandexValuationScraper._parse_item_text(text)
+    # '2,2' would need (?<!\\d) — `,` is not digit, so lookbehind allows start.
+    # But `\\d{2,4}` needs ≥2 leading digits — '2,' only has one. No match.
+    assert item is None or item.area_m2 is None