[FEAT] 월 생략 날짜 파싱 고도화

app/services/parser_service.py

@@ -30,6 +30,15 @@
     re.compile(r"(?<![\d/.-])(?P<month>\d{1,2})/(?P<day>\d{1,2})(?![\d/.-])"),
 ]
 
+# 종료일의 월이 생략된 범위를 처리합니다: 8월 20일부터 22일까지, 20일 부터 22일까지.
+INHERITED_MONTH_DATE_RANGE_PATTERN = re.compile(
+    r"(?<!\d)"
+    r"(?:(?P<year>\d{4})년\s*)?"
+    r"(?:(?P<month>\d{1,2})월\s*)?"
+    r"(?P<start_day>\d{1,2})일\s*부터\s*"
+    r"(?P<end_day>\d{1,2})일\s*까지"
+)
+
 # 오전/오후, 반, 분, 쯤/경이 포함된 시간 표현을 처리합니다.
 TIME_PATTERN = re.compile(
     r"(?:(?P<period>오전|오후|저녁|아침|밤|새벽|점심|낮)(?:에)?\s*)?"
@@ -171,6 +180,8 @@ def _extract_date(source_text: str, reference_date: date | None = None) -> Extra
     candidates: list[tuple[int, int, ExtractedValue]] = []
     removable_texts: list[str] = []
 
+    inherited_month_range = _extract_inherited_month_date_range(source_text, today)
+
     for pattern in DATE_PATTERNS:
         for match in pattern.finditer(source_text):
             year = int(match.groupdict().get("year") or today.year)
@@ -307,8 +318,29 @@ def _extract_date(source_text: str, reference_date: date | None = None) -> Extra
             )
 
     date_range = _extract_date_range(source_text, candidates, removable_texts)
-    if date_range.value is not None:
-        return date_range
+    range_candidates = [
+        candidate
+        for candidate in (date_range, inherited_month_range)
+        if candidate is not None
+    ]
+    if range_candidates:
+        _, selected_range = min(range_candidates, key=lambda candidate: candidate[0])
+        range_removable_texts = [
+            removable_text
+            for _, candidate in range_candidates
+            for removable_text in candidate.removable_texts
+        ]
+        return ExtractedValue(
+            value=selected_range.value,
+            end_value=selected_range.end_value,
+            text=selected_range.text,
+            removable_texts=_dedupe_longest_first(
+                [*removable_texts, *range_removable_texts]
+            ),
+            date_source=selected_range.date_source,
+            is_past=selected_range.is_past,
+            is_ambiguous=selected_range.is_ambiguous,
+        )
 
     if candidates:
         selected = min(candidates, key=lambda candidate: candidate[0])[2]
@@ -324,6 +356,38 @@ def _extract_date(source_text: str, reference_date: date | None = None) -> Extra
     return ExtractedValue(value=None)
 
 
+def _extract_inherited_month_date_range(
+    source_text: str,
+    today: date,
+) -> tuple[int, ExtractedValue] | None:
+    """생략된 월은 시작일의 월 또는 서비스 기준 현재 월로 보완해 날짜 범위를 반환합니다."""
+    match = INHERITED_MONTH_DATE_RANGE_PATTERN.search(source_text)
+    if match is None:
+        return None
+
+    year = int(match.group("year") or today.year)
+    month = int(match.group("month") or today.month)
+
+    try:
+        start_date = date(year, month, int(match.group("start_day")))
+        end_date = date(year, month, int(match.group("end_day")))
+    except ValueError:
+        return None
+
+    removable_text = match.group(0)
+    return (
+        match.start(),
+        ExtractedValue(
+            value=start_date.isoformat(),
+            end_value=end_date.isoformat() if end_date >= start_date else None,
+            text=removable_text,
+            removable_texts=[removable_text],
+            date_source="EXPLICIT",
+            is_past=start_date < today,
+        ),
+    )
+
+
 def _add_relative_week_candidates_without_weekday(
     source_text: str,
     today: date,
@@ -372,7 +436,7 @@ def _extract_date_range(
     source_text: str,
     candidates: list[tuple[int, int, ExtractedValue]],
     removable_texts: list[str],
-) -> ExtractedValue:
+) -> tuple[int, ExtractedValue] | None:
     """A부터 B까지 형태의 날짜 범위를 시작일/종료일 후보로 분리합니다."""
     sorted_candidates = sorted(candidates, key=lambda candidate: candidate[0])
     for start_index, start_end, start_date in sorted_candidates:
@@ -393,17 +457,20 @@ def _extract_date_range(
 
             removable_text = source_text[start_index : end_end + until_match.end()]
             removable_texts.append(removable_text)
-            return ExtractedValue(
-                value=start_date.value,
-                end_value=end_date.value,
-                text=removable_text,
-                removable_texts=_dedupe_longest_first(removable_texts),
-                date_source=_combine_date_source(start_date.date_source, end_date.date_source),
-                is_past=start_date.is_past,
-                is_ambiguous=start_date.is_ambiguous or end_date.is_ambiguous,
+            return (
+                start_index,
+                ExtractedValue(
+                    value=start_date.value,
+                    end_value=end_date.value,
+                    text=removable_text,
+                    removable_texts=_dedupe_longest_first(removable_texts),
+                    date_source=_combine_date_source(start_date.date_source, end_date.date_source),
+                    is_past=start_date.is_past,
+                    is_ambiguous=start_date.is_ambiguous or end_date.is_ambiguous,
+                ),
             )
 
-    return ExtractedValue(value=None)
+    return None
 
 
 def _align_bare_weekday_start_to_qualified_week_end(

tests/test_parser_service.py

@@ -59,6 +59,62 @@ def test_explicit_date_range_sets_start_and_end_date():
     assert result.to_embedding == ["부산", "여행"]
 
 
+def test_date_range_inherits_start_month_when_end_month_is_omitted():
+    result = parse_event_text(
+        "8월 20일부터 22일까지 부산 여행",
+        reference_date=date(2026, 8, 17),
+    )
+
+    assert result.start_date == "2026-08-20"
+    assert result.end_date == "2026-08-22"
+    assert result.date_source == "EXPLICIT"
+    assert result.to_embedding == ["부산", "여행"]
+
+
+def test_date_range_uses_reference_month_when_both_months_are_omitted():
+    result = parse_event_text(
+        "20일 부터 22일까지 부산 여행",
+        reference_date=date(2026, 8, 17),
+    )
+
+    assert result.start_date == "2026-08-20"
+    assert result.end_date == "2026-08-22"
+    assert result.date_source == "EXPLICIT"
+    assert result.to_embedding == ["부산", "여행"]
+
+
+def test_inherited_month_date_range_does_not_roll_inverted_end_to_next_month():
+    result = parse_event_text(
+        "8월 30일부터 2일까지 부산 여행",
+        reference_date=date(2026, 8, 17),
+    )
+
+    assert result.start_date == "2026-08-30"
+    assert result.end_date is None
+    assert result.date_source == "EXPLICIT"
+    assert result.to_embedding == ["부산", "여행"]
+
+
+def test_date_range_selects_earliest_standard_range_before_inherited_range():
+    result = parse_event_text(
+        "8월 18일부터 8월 19일까지 출장 후 8월 20일부터 22일까지 여행",
+        reference_date=date(2026, 8, 17),
+    )
+
+    assert result.start_date == "2026-08-18"
+    assert result.end_date == "2026-08-19"
+
+
+def test_date_range_selects_earliest_inherited_range_before_standard_range():
+    result = parse_event_text(
+        "8월 20일부터 22일까지 여행 후 8월 24일부터 8월 25일까지 출장",
+        reference_date=date(2026, 8, 17),
+    )
+
+    assert result.start_date == "2026-08-20"
+    assert result.end_date == "2026-08-22"
+
+
 def test_relative_date_range_sets_start_and_end_date(monkeypatch):
     import app.services.parser_service as parser_service