Bind number-only Part headings to shared navigation translations

src/preprocessing/navigation.py

@@ -115,7 +115,10 @@ def _headings(soup, target, label):
             group = blocks[start:end]
             if any(len(plain(t.get_text())) > 300 for t in group): break
             combined = ' '.join(t.get_text(' ', strip=True) for t in group)
-            if title_identity(combined) == identity and identity:
+            number_only = (not identity and len(group) == 1 and group[0].name in HEADINGS
+                           and number_info(label)[0] is not None
+                           and number_info(combined) == number_info(label))
+            if title_identity(combined) == identity and (identity or number_only):
                 matches.append(group)
     # A number leaf and the subtitle alone can both match after stripping a
     # numeric prefix. Prefer the complete adjacent title group.
@@ -225,11 +228,11 @@ def normalize_heading_html(record, html):
             and re.fullmatch(r'[章部篇][：:]?',plain(str(nodes[2])))):
         nodes[1].replace_with(chinese_number(record['number']))
         nodes[2].replace_with('章' if record['role']=='chapter' else '部')
-    elif re.fullmatch(r'(?:\d+|[IVXLCDM]+|第[零一二三四五六七八九十百千万\d]+[章部篇])',compact,re.I):
+    elif re.fullmatch(r'(?:\d+|[IVXLCDM]+|第[零一二三四五六七八九十百千万\d]+(?:章|部分?|篇))',compact,re.I):
         node.replace_with(prefix)
         if len(nodes)>1 and plain(str(nodes[1])) in {':','：'}: nodes[1].replace_with('')
     elif re.match(r'^第[零一二三四五六七八九十百千万\d]+[章部篇]',compact):
-        node.replace_with(re.sub(r'^第[零一二三四五六七八九十百千万\d]+[章部篇]',prefix,compact))
+        node.replace_with(re.sub(r'^第[零一二三四五六七八九十百千万\d]+(?:章|部分?|篇)',prefix,compact))
     return root.decode_contents()