Merge pull request #10 from krrome/bug-skip-empty-headers-list

fix #8

Author: krrome

hierarchical/hierarchy_builder.py

@@ -309,6 +309,8 @@ def _cluster_headings_dbscan(self) -> dict[int, int]:
         return heading_to_level
 
     def infer(self) -> HierarchicalHeader:
+        if len(self.headings) == 0:
+            return HierarchicalHeader()
         try:
             if (root_node := self._infer_from_numbering()) is not None:
                 return root_node

tests/test_toc.py

@@ -1994,6 +1994,12 @@ def test_sample_9():
     compare(str(root_node), 9)
 
 
+def test_skip_empty_header_list():
+    root_node = create_toc([])
+    assert root_node.parent is None
+    assert len(root_node.children) == 0
+
+
 def test_flatten_hierarchy_tree():
     root_node = create_toc(sample_0)
     current_non_num_level = 1