Fixing DeepLake Overwrite Flag (#4683)

# Fix DeepLake Overwrite Flag Issue

Fixes Issue #4682: essentially, setting overwrite to False in the
DeepLake constructor still triggers an overwrite, because the logic is
just checking for the presence of "overwrite" in kwargs. The fix is
simple--just add some checks to inspect if "overwrite" in kwargs AND
kwargs["overwrite"]==True.

Added a new test in
tests/integration_tests/vectorstores/test_deeplake.py to reflect the
desired behavior.


Co-authored-by: Anirudh Suresh <ani@Anirudhs-MBP.cable.rcn.com>
Co-authored-by: Anirudh Suresh <ani@Anirudhs-MacBook-Pro.local>
Co-authored-by: Dev 2049 <dev.dev2049@gmail.com>

tests/integration_tests/vectorstores/test_deeplake.py

@@ -83,6 +83,53 @@ def test_deeplakewith_persistence() -> None:
     # Or on program exit
 
 
+def test_deeplake_overwrite_flag() -> None:
+    """Test overwrite behavior"""
+    dataset_path = "./tests/persist_dir"
+    if deeplake.exists(dataset_path):
+        deeplake.delete(dataset_path)
+
+    texts = ["foo", "bar", "baz"]
+    docsearch = DeepLake.from_texts(
+        dataset_path=dataset_path,
+        texts=texts,
+        embedding=FakeEmbeddings(),
+    )
+    output = docsearch.similarity_search("foo", k=1)
+    assert output == [Document(page_content="foo")]
+
+    docsearch.persist()
+
+    # Get a new VectorStore from the persisted directory, with no overwrite (implicit)
+    docsearch = DeepLake(
+        dataset_path=dataset_path,
+        embedding_function=FakeEmbeddings(),
+    )
+    output = docsearch.similarity_search("foo", k=1)
+    # assert page still present
+    assert output == [Document(page_content="foo")]
+
+    # Get a new VectorStore from the persisted directory, with no overwrite (explicit)
+    docsearch = DeepLake(
+        dataset_path=dataset_path,
+        embedding_function=FakeEmbeddings(),
+        overwrite=False,
+    )
+    output = docsearch.similarity_search("foo", k=1)
+    # assert page still present
+    assert output == [Document(page_content="foo")]
+
+    # Get a new VectorStore from the persisted directory, with overwrite
+    docsearch = DeepLake(
+        dataset_path=dataset_path,
+        embedding_function=FakeEmbeddings(),
+        overwrite=True,
+    )
+    output = docsearch.similarity_search("foo", k=1)
+    # assert page no longer present
+    assert output == []
+
+
 def test_similarity_search(deeplake_datastore: DeepLake, distance_metric: str) -> None:
     """Test similarity search."""
     output = deeplake_datastore.similarity_search(