fix(kg): resolve 'unhashable type: Entity' in GraphAnalyzer #159

- Robust ID extraction in CentralityCalculator, CommunityDetector, and ConnectivityAnalyzer
- Support for direct Entity objects and dictionaries as node identifiers
- Improved Entity hashability in utils/types.py
- Added integration test to verify fix and prevent regression

tests/split/test_splitter.py

@@ -0,0 +1,53 @@
+import unittest
+from unittest.mock import MagicMock, patch
+from semantica.split.splitter import TextSplitter
+from semantica.split.semantic_chunker import SemanticChunker, Chunk
+
+class TestSplitter(unittest.TestCase):
+
+    def setUp(self):
+        self.mock_logger = MagicMock()
+        self.logger_patcher = patch('semantica.split.splitter.get_logger', return_value=self.mock_logger)
+        self.logger_patcher_sc = patch('semantica.split.semantic_chunker.get_logger', return_value=self.mock_logger)
+        self.tracker_patcher = patch('semantica.split.semantic_chunker.get_progress_tracker', return_value=MagicMock())
+        
+        self.logger_patcher.start()
+        self.logger_patcher_sc.start()
+        self.tracker_patcher.start()
+
+    def tearDown(self):
+        self.logger_patcher.stop()
+        self.logger_patcher_sc.stop()
+        self.tracker_patcher.stop()
+
+    def test_text_splitter_initialization(self):
+        splitter = TextSplitter(method="recursive", chunk_size=500, chunk_overlap=50)
+        self.assertEqual(splitter.chunk_size, 500)
+        self.assertEqual(splitter.chunk_overlap, 50)
+        self.assertEqual(splitter.methods, ["recursive"])
+
+    def test_text_splitter_list_methods(self):
+        splitter = TextSplitter(method=["recursive", "token"])
+        self.assertEqual(splitter.methods, ["recursive", "token"])
+
+    @patch('semantica.split.semantic_chunker.spacy')
+    def test_semantic_chunker_initialization(self, mock_spacy):
+        # Mock spacy.load to return a mock nlp object
+        mock_nlp = MagicMock()
+        mock_spacy.load.return_value = mock_nlp
+        
+        # We need to ensure SPACY_AVAILABLE is True for this test context if possible, 
+        # but it is imported at module level. 
+        # If spacy is not installed, it sets SPACY_AVAILABLE = False.
+        # We might need to patch the module attribute or just test fallback if spacy missing.
+        
+        chunker = SemanticChunker(chunk_size=100)
+        self.assertEqual(chunker.chunk_size, 100)
+
+    def test_chunk_dataclass(self):
+        chunk = Chunk(text="test", start_index=0, end_index=4, metadata={"key": "value"})
+        self.assertEqual(chunk.text, "test")
+        self.assertEqual(chunk.metadata["key"], "value")
+
+if __name__ == '__main__':
+    unittest.main()