From 4c523a252ab81320c68f9e235c860cb796a94643 Mon Sep 17 00:00:00 2001
From: Vlada Dusek <v.dusek96@gmail.com>
Date: Wed, 12 Aug 2026 11:07:19 +0200
Subject: [PATCH 1/2] fix(storage-clients): restore
 `DatasetClient._is_sequence_of_items` for released Apify SDK versions

---
 .../storage_clients/_base/_dataset_client.py  | 16 +++++++++-
 .../test_base_dataset_client.py               | 30 +++++++++++++++++++
 2 files changed, 45 insertions(+), 1 deletion(-)
 create mode 100644 tests/unit/storage_clients/test_base_dataset_client.py

diff --git a/src/crawlee/storage_clients/_base/_dataset_client.py b/src/crawlee/storage_clients/_base/_dataset_client.py
index e1a3c4b468..bd13144e52 100644
--- a/src/crawlee/storage_clients/_base/_dataset_client.py
+++ b/src/crawlee/storage_clients/_base/_dataset_client.py
@@ -1,10 +1,11 @@
 from __future__ import annotations
 
 from abc import ABC, abstractmethod
+from collections.abc import Sequence
 from typing import TYPE_CHECKING
 
 if TYPE_CHECKING:
-    from collections.abc import AsyncIterator, Mapping, Sequence
+    from collections.abc import AsyncIterator, Mapping
 
     from crawlee._types import JsonSerializable
     from crawlee.storage_clients.models import DatasetItemsListPage, DatasetMetadata
@@ -91,3 +92,16 @@ async def iterate_items(
         raise NotImplementedError
         if False:
             yield {}
+
+    @staticmethod
+    def _is_sequence_of_items(
+        data: Sequence[Mapping[str, JsonSerializable]] | Mapping[str, JsonSerializable],
+    ) -> bool:
+        """Tell whether the `push_data` payload is a sequence of items rather than a single item.
+
+        No `push_data` implementation in this repository uses this helper - it is inlined there instead. It stays
+        on the base class because the Apify SDK up to 4.0.1 calls it from `ApifyDatasetClient.push_data`, so
+        removing it breaks every Actor that resolves such an SDK version against this package. Drop it in the
+        next major version, once those SDK versions are out of the supported range.
+        """
+        return isinstance(data, Sequence)
diff --git a/tests/unit/storage_clients/test_base_dataset_client.py b/tests/unit/storage_clients/test_base_dataset_client.py
new file mode 100644
index 0000000000..4f16628e2a
--- /dev/null
+++ b/tests/unit/storage_clients/test_base_dataset_client.py
@@ -0,0 +1,30 @@
+from __future__ import annotations
+
+import pytest
+
+from crawlee.storage_clients._base import DatasetClient
+from crawlee.storage_clients._memory import MemoryDatasetClient
+
+
+@pytest.mark.parametrize(
+    ('data', 'expected'),
+    [
+        pytest.param([{'a': 1}, {'a': 2}], True, id='sequence of items'),
+        pytest.param([], True, id='empty sequence'),
+        pytest.param({'a': 1}, False, id='single item'),
+        pytest.param({}, False, id='empty single item'),
+    ],
+)
+def test_is_sequence_of_items_distinguishes_payload_shapes(
+    data: list[dict[str, int]] | dict[str, int],
+    *,
+    expected: bool,
+) -> None:
+    """`_is_sequence_of_items` reports whether a `push_data` payload holds many items or just one."""
+    assert DatasetClient._is_sequence_of_items(data) is expected
+
+
+def test_is_sequence_of_items_is_inherited_by_concrete_clients() -> None:
+    """Concrete clients inherit `_is_sequence_of_items`, the way the Apify SDK up to 4.0.1 calls it on itself."""
+    assert MemoryDatasetClient._is_sequence_of_items([{'a': 1}]) is True
+    assert MemoryDatasetClient._is_sequence_of_items({'a': 1}) is False

From dbb267d10dfa0d83473b8da168c800b74e17be90 Mon Sep 17 00:00:00 2001
From: Vlada Dusek <v.dusek96@gmail.com>
Date: Wed, 12 Aug 2026 11:21:01 +0200
Subject: [PATCH 2/2] test: drop the base dataset client shim tests

---
 .../test_base_dataset_client.py               | 30 -------------------
 1 file changed, 30 deletions(-)
 delete mode 100644 tests/unit/storage_clients/test_base_dataset_client.py

diff --git a/tests/unit/storage_clients/test_base_dataset_client.py b/tests/unit/storage_clients/test_base_dataset_client.py
deleted file mode 100644
index 4f16628e2a..0000000000
--- a/tests/unit/storage_clients/test_base_dataset_client.py
+++ /dev/null
@@ -1,30 +0,0 @@
-from __future__ import annotations
-
-import pytest
-
-from crawlee.storage_clients._base import DatasetClient
-from crawlee.storage_clients._memory import MemoryDatasetClient
-
-
-@pytest.mark.parametrize(
-    ('data', 'expected'),
-    [
-        pytest.param([{'a': 1}, {'a': 2}], True, id='sequence of items'),
-        pytest.param([], True, id='empty sequence'),
-        pytest.param({'a': 1}, False, id='single item'),
-        pytest.param({}, False, id='empty single item'),
-    ],
-)
-def test_is_sequence_of_items_distinguishes_payload_shapes(
-    data: list[dict[str, int]] | dict[str, int],
-    *,
-    expected: bool,
-) -> None:
-    """`_is_sequence_of_items` reports whether a `push_data` payload holds many items or just one."""
-    assert DatasetClient._is_sequence_of_items(data) is expected
-
-
-def test_is_sequence_of_items_is_inherited_by_concrete_clients() -> None:
-    """Concrete clients inherit `_is_sequence_of_items`, the way the Apify SDK up to 4.0.1 calls it on itself."""
-    assert MemoryDatasetClient._is_sequence_of_items([{'a': 1}]) is True
-    assert MemoryDatasetClient._is_sequence_of_items({'a': 1}) is False