feat(qwen): split chunks at symbols and sections

scripts/test-retrieval-server.py

@@ -175,6 +175,30 @@ class RetrievalServerTests(unittest.TestCase):
                 reconstructed = windows[0] + [word for window in windows[1:] for word in window[64:]]
                 self.assertEqual(reconstructed, words)
 
+    def test_python_symbols_include_decorators_and_restore_parent(self):
+        source = 'class Service:\n    @cached\n    def load(self):\n        return 1\n\nvalue = 2\n\nasync def refresh():\n    return value\n'
+        result = list(MODULE.sections(source, 'service.py'))
+        self.assertEqual([symbol for symbol, _ in result], ['Service', 'Service.load', '<module>', 'refresh'])
+        self.assertIn('@cached', result[1][1])
+        self.assertEqual(''.join(content for _, content in result), source)
+        broken = 'def incomplete(\n' + 'word ' * 450
+        self.assertEqual(len(list(MODULE.chunks(broken, 'broken.py', tokenize))), 2)
+
+    def test_markdown_sections_ignore_fenced_headings(self):
+        source = '# Setup\nIntro\n## Install\n```sh\n# not a heading\n```\nSteps\n## Run\nStart\n'
+        result = list(MODULE.chunks(source, 'guide.md', tokenize))
+        self.assertEqual([symbol for symbol, _ in result], ['Setup', 'Setup / Install', 'Setup / Run'])
+        self.assertIn('# not a heading', result[1][1])
+
+    def test_common_declarations_and_config_sections(self):
+        for path, source, symbols in [
+            ('service.ts', 'export function load() {\n return 1;\n}\nexport const save = () => 2;\n', ['load', 'save']),
+            ('service.cs', 'public class Service\n{\n public void Load()\n {\n }\n}\n', ['Service', 'Load']),
+            ('setup.ps1', 'function Get-Result {\n return 1\n}\n', ['Get-Result']),
+            ('config.toml', '[server]\nport = 1\n[client]\nport = 2\n', ['server', 'client']),
+        ]:
+            self.assertEqual([symbol for symbol, _ in MODULE.sections(source, path)], symbols)
+
     def test_old_cache_is_preserved_but_not_reused(self):
         with TemporaryDirectory() as temporary:
             root = Path(temporary)