first commit

Co-authored-by: Cursor <cursoragent@cursor.com>

backend/tests/test_parent_child.py

@@ -0,0 +1,80 @@
+"""Tests for parent/child delimiter splitting."""
+
+from __future__ import annotations
+
+import tempfile
+import unittest
+from pathlib import Path
+
+from rag_cut.models import Block, BlockType, SplitConfig, SplitMode
+from rag_cut.pipeline import chunk_document
+from rag_cut.splitters.parent_child import split_by_parent_child
+
+
+def p(text: str) -> Block:
+    return Block(type=BlockType.PARAGRAPH, text=text)
+
+
+class ParentChildSplitTest(unittest.TestCase):
+    def test_parent_and_child_chunks_are_linked(self) -> None:
+        blocks = [p("Intro A##Detail A1###Detail A2##Intro B###Detail B1")]
+        groups = split_by_parent_child(
+            blocks,
+            SplitConfig(
+                mode=SplitMode.PARENT_CHILD,
+                parent_delimiter="##",
+                child_delimiter="###",
+                max_chunk_size=2000,
+                child_max_size=500,
+                overlap=0,
+            ),
+        )
+
+        parents = [g for g in groups if g.meta.get("is_section_parent")]
+        children = [g for g in groups if g.meta.get("is_sub_chunk")]
+        self.assertGreaterEqual(len(parents), 2)
+        self.assertGreaterEqual(len(children), 2)
+        self.assertTrue(all(g.meta.get("retrieval") is False for g in parents))
+        self.assertTrue(all(g.meta.get("retrieval") is True for g in children))
+        self.assertTrue(all(g.meta.get("parent_section_id") for g in children))
+
+    def test_requires_parent_delimiter(self) -> None:
+        with self.assertRaises(ValueError):
+            split_by_parent_child(
+                [p("hello")],
+                SplitConfig(mode=SplitMode.PARENT_CHILD, parent_delimiter=None),
+            )
+
+    def test_pipeline_persists_parent_chunk_ids(self) -> None:
+        with tempfile.TemporaryDirectory() as tmp:
+            source = Path(tmp) / "pc.md"
+            source.write_text(
+                "Alpha parent##A1 child###A2 child##Beta parent###B1 child",
+                encoding="utf-8",
+            )
+            result = chunk_document(
+                source,
+                config=SplitConfig(
+                    mode=SplitMode.PARENT_CHILD,
+                    parent_delimiter="##",
+                    child_delimiter="###",
+                    max_chunk_size=2000,
+                    child_max_size=400,
+                    overlap=0,
+                ),
+                storage_root=Path(tmp) / "storage",
+            )
+
+        self.assertEqual(result.split_mode, SplitMode.PARENT_CHILD)
+        self.assertEqual(result.split_config.get("chunk_strategy"), "parent_child_delimiter")
+        parents = [c for c in result.chunks if c.meta.get("is_section_parent")]
+        children = [c for c in result.chunks if c.meta.get("is_sub_chunk")]
+        self.assertTrue(parents)
+        self.assertTrue(children)
+        for child in children:
+            self.assertIn("parent_chunk_id", child.meta)
+            self.assertIsInstance(child.meta["parent_chunk_id"], int)
+
+
+if __name__ == "__main__":
+    unittest.main()