feat(normalizer): day-first month-name matcher

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

tools/import-normalizer/dates.py

@@ -134,8 +134,31 @@ def _match_roman(s):
         return None
 
 
+_MONTH_A_RE = re.compile(r"(\d{1,2})[.\s]*([A-Za-zÄÖÜäöü]+)\.?\s*(\d{2,4})")
+
+
+def _lookup_month(token: str):
+    return config.MONTHS.get(token.lower().strip(" ."))
+
+
+def _build_day_month_year(day, month, year):
+    if not month or year is None or not (1 <= month <= 12):
+        return None
+    try:
+        return datetime.date(year, month, day).isoformat(), Precision.DAY
+    except ValueError:
+        return None
+
+
+def _match_monthname_a(s):
+    m = _MONTH_A_RE.fullmatch(s)
+    if not m:
+        return None
+    return _build_day_month_year(int(m.group(1)), _lookup_month(m.group(2)), expand_year(m.group(3)))
+
+
 # Matchers are tried in order. Later tasks append to this list.
-_MATCHERS = [_match_iso, _match_numeric, _match_roman]
+_MATCHERS = [_match_iso, _match_numeric, _match_roman, _match_monthname_a]
 
 
 def parse_date(raw: str, date_overrides: dict | None = None) -> ParsedDate:

tools/import-normalizer/tests/test_dates.py

@@ -55,9 +55,9 @@ def test_parse_numeric_unparseable():
     assert dates.parse_date("13.5.65").precision == Precision.UNKNOWN  # ambiguous 2-digit year
 
 def test_parse_approx_marker_upgrades_precision():
-    r = dates.parse_date("17.Nov (?) 1887")  # month-name handled in a later task; here just the marker path
+    r = dates.parse_date("17.Nov (?) 1887")  # month-name matcher now active; (?) marks approx
     assert r.raw == "17.Nov (?) 1887"
-    assert r.precision == Precision.UNKNOWN  # no month-name matcher until Task 7; full APPROX check in Task 8
+    assert r.precision == Precision.APPROX  # month-name matcher parses date; (?) upgrades to APPROX
 
 def test_parse_leading_qualifier_is_approx():
     r = dates.parse_date("nach 1.5.1900")  # qualifier stripped, numeric date salvaged, precision APPROX
@@ -69,3 +69,12 @@ def test_parse_roman_months():
     assert dates.parse_date("19.XII.1954").iso == "1954-12-19"
     assert dates.parse_date("1.III.27").iso == "1927-03-01"
     assert dates.parse_date("22.III.18").precision == Precision.DAY
+
+def test_parse_monthname_day_first():
+    assert dates.parse_date("6.März 1888").iso == "1888-03-06"
+    assert dates.parse_date("29.Sept.1891").iso == "1891-09-29"
+    assert dates.parse_date("10.Oct.95").iso == "1895-10-10"
+    assert dates.parse_date("9.December1889").iso == "1889-12-09"
+    assert dates.parse_date("18.Dez.1916").iso == "1916-12-18"
+    assert dates.parse_date("4Dezember 1936").iso == "1936-12-04"
+    assert dates.parse_date("25 August 1968").iso == "1968-08-25"