fix: correct assert syntax in test_empty_model_suffix to prevent false positives

Why this change is needed:
The test file contained assert statements using tuple syntax `assert (condition, message)`,
which Python interprets as asserting a non-empty tuple (always True). This meant the tests
were passing even when the actual conditions failed, creating a false sense of test coverage.
Additionally, there were unused imports (pytest, patch, MagicMock) that needed cleanup.

How it solves it:
- Fixed assert statements on lines 61-63 and 105-109 to use correct syntax:
  `assert condition, message` instead of `assert (condition, message)`
- Removed unused imports to satisfy linter requirements
- Applied automatic formatting via ruff-format and ruff

Impact:
- Tests now correctly validate the empty model suffix behavior
- Prevents false positive test results that could hide bugs
- Passes all pre-commit hooks (F631 error resolved)

Testing:
- Verified with `uv run pre-commit run --all-files` - all checks pass
- Assert statements now properly fail when conditions are not met

tests/test_empty_model_suffix.py

@@ -5,8 +5,8 @@ This test module verifies that both storage backends gracefully handle
 the case when _generate_collection_suffix() returns an empty string.
 """
 
-import pytest
+from unittest.mock import Mock
-from unittest.mock import Mock, patch, MagicMock
+
 from lightrag.base import BaseVectorStorage
 from lightrag.utils import EmbeddingFunc
 
@@ -58,10 +58,9 @@ class TestEmptyModelSuffix:
         # 2. table_name doesn't have trailing underscore
         # 3. table_name equals the base table name
         assert storage.model_suffix == "", "model_suffix should be empty"
-        assert (
+        assert not storage.table_name.endswith(
-            not storage.table_name.endswith("_"),
+            "_"
-            f"table_name should not have trailing underscore: {storage.table_name}",
+        ), f"table_name should not have trailing underscore: {storage.table_name}"
-        )
 
         # Expected base table name
         expected_base = namespace_to_table_name("chunks")
@@ -102,13 +101,12 @@ class TestEmptyModelSuffix:
         # 1. model_suffix is empty
         # 2. final_namespace doesn't have trailing underscore
         # 3. final_namespace equals the legacy namespace
-        assert storage._generate_collection_suffix() == "", (
-            "model_suffix should be empty"
-        )
         assert (
-            not storage.final_namespace.endswith("_"),
+            storage._generate_collection_suffix() == ""
-            f"final_namespace should not have trailing underscore: {storage.final_namespace}",
+        ), "model_suffix should be empty"
-        )
+        assert not storage.final_namespace.endswith(
+            "_"
+        ), f"final_namespace should not have trailing underscore: {storage.final_namespace}"
         assert storage.final_namespace == storage.legacy_namespace, (
             f"final_namespace should fallback to legacy_namespace when model_suffix is empty. "
             f"Expected: {storage.legacy_namespace}, Got: {storage.final_namespace}"
@@ -127,7 +125,9 @@ class TestEmptyModelSuffix:
 
         # Create a proper embedding function with model_name
         embedding_func = EmbeddingFunc(
-            embedding_dim=1536, func=dummy_embedding_func, model_name="text-embedding-ada-002"
+            embedding_dim=1536,
+            func=dummy_embedding_func,
+            model_name="text-embedding-ada-002",
         )
 
         # Setup global_config
@@ -154,16 +154,18 @@ class TestEmptyModelSuffix:
         # 1. model_suffix is not empty
         # 2. table_name has correct format
         assert storage.model_suffix != "", "model_suffix should not be empty"
-        assert "_" in storage.table_name, "table_name should contain underscore as separator"
+        assert (
+            "_" in storage.table_name
+        ), "table_name should contain underscore as separator"
 
         # Expected format: base_table_model_suffix
         expected_base = namespace_to_table_name("chunks")
         expected_model_id = embedding_func.get_model_identifier()
         expected_table_name = f"{expected_base}_{expected_model_id}"
 
-        assert storage.table_name == expected_table_name, (
+        assert (
-            f"table_name format incorrect. Expected: {expected_table_name}, Got: {storage.table_name}"
+            storage.table_name == expected_table_name
-        )
+        ), f"table_name format incorrect. Expected: {expected_table_name}, Got: {storage.table_name}"
 
     def test_qdrant_collection_name_with_valid_suffix(self):
         """
@@ -177,7 +179,9 @@ class TestEmptyModelSuffix:
 
         # Create a proper embedding function with model_name
         embedding_func = EmbeddingFunc(
-            embedding_dim=1536, func=dummy_embedding_func, model_name="text-embedding-ada-002"
+            embedding_dim=1536,
+            func=dummy_embedding_func,
+            model_name="text-embedding-ada-002",
         )
 
         # Setup global_config
@@ -200,17 +204,17 @@ class TestEmptyModelSuffix:
         # 2. final_namespace has correct format
         model_suffix = storage._generate_collection_suffix()
         assert model_suffix != "", "model_suffix should not be empty"
-        assert "_" in storage.final_namespace, (
+        assert (
-            "final_namespace should contain underscore as separator"
+            "_" in storage.final_namespace
-        )
+        ), "final_namespace should contain underscore as separator"
 
         # Expected format: lightrag_vdb_namespace_model_suffix
         expected_model_id = embedding_func.get_model_identifier()
         expected_collection_name = f"lightrag_vdb_chunks_{expected_model_id}"
 
-        assert storage.final_namespace == expected_collection_name, (
+        assert (
-            f"final_namespace format incorrect. Expected: {expected_collection_name}, Got: {storage.final_namespace}"
+            storage.final_namespace == expected_collection_name
-        )
+        ), f"final_namespace format incorrect. Expected: {expected_collection_name}, Got: {storage.final_namespace}"
 
     def test_suffix_generation_fallback_chain(self):
         """
@@ -221,7 +225,6 @@ class TestEmptyModelSuffix:
         2. Global config fallback: global_config["embedding_func"].get_model_identifier()
         3. Final fallback: return empty string
         """
-        from lightrag.base import BaseVectorStorage
 
         # Create a concrete implementation for testing
         class TestStorage(BaseVectorStorage):
@@ -288,7 +291,6 @@ class TestEmptyModelSuffix:
             global_config={},
             embedding_func=mock_embedding_func,
         )
-        assert storage._generate_collection_suffix() == "", (
+        assert (
-            "Should return empty string when no model_identifier available"
+            storage._generate_collection_suffix() == ""
-        )
+        ), "Should return empty string when no model_identifier available"
-