🛡️ Shield: Fix silent failure in JsonListPaginator

imednet/core/paginator.py

@@ -105,10 +105,9 @@ def _iter_sync(self) -> Iterator[Any]:
         # Raw list endpoints do not support pagination params
         response: httpx.Response = client.get(self.path, params=self.params)
         payload = response.json()
-        if isinstance(payload, list):
-            yield from payload
-        else:
-            yield from []
+        if not isinstance(payload, list):
+            raise TypeError(f"API response must be a list, got {type(payload).__name__}")
+        yield from payload
 
 
 class AsyncJsonListPaginator(AsyncPaginator):
@@ -119,9 +118,7 @@ async def _iter_async(self) -> AsyncIterator[Any]:
         # Raw list endpoints do not support pagination params
         response: httpx.Response = await client.get(self.path, params=self.params)
         payload = response.json()
-        if isinstance(payload, list):
-            for item in payload:
-                yield item
-        else:
-            # Fallback for empty or malformed response
-            pass
+        if not isinstance(payload, list):
+            raise TypeError(f"API response must be a list, got {type(payload).__name__}")
+        for item in payload:
+            yield item

pyproject.toml

@@ -80,7 +80,7 @@ faker = "^24.9"
 pre-commit = "^4.2.0"
 virtualenv = "^20.36.1"
 isort = "^6.0.1"
-werkzeug = "^3.1.5"
+werkzeug = "^3.1.6"
 sphinx = "^6.2.0"
 sphinx-autodoc-typehints = "*"
 sphinx-rtd-theme = "^3.0.2"

tests/unit/test_json_list_paginator_robustness.py

@@ -0,0 +1,71 @@
+from unittest.mock import Mock
+
+import pytest
+
+from imednet.core.paginator import AsyncJsonListPaginator, JsonListPaginator
+
+
+class MockClient:
+    def __init__(self, response_data):
+        self.response_data = response_data
+
+    def get(self, path, params=None):
+        response = Mock()
+        response.json.return_value = self.response_data
+        return response
+
+
+class MockAsyncClient:
+    def __init__(self, response_data):
+        self.response_data = response_data
+
+    async def get(self, path, params=None):
+        response = Mock()
+        response.json.return_value = self.response_data
+        return response
+
+
+def test_json_list_paginator_raises_on_dict():
+    """
+    Test that JsonListPaginator raises TypeError when the API returns a dictionary
+    instead of the expected list.
+    """
+    # Simulate an error response or unexpected object structure
+    client = MockClient({"error": "Something went wrong", "details": "Unexpected format"})
+    paginator = JsonListPaginator(client, "/path")
+
+    # Currently this fails (returns empty list), we want it to raise TypeError
+    with pytest.raises(TypeError, match="API response must be a list"):
+        list(paginator)
+
+
+def test_json_list_paginator_raises_on_none():
+    """Test that JsonListPaginator raises TypeError when the API returns null."""
+    client = MockClient(None)
+    paginator = JsonListPaginator(client, "/path")
+
+    with pytest.raises(TypeError, match="API response must be a list"):
+        list(paginator)
+
+
+@pytest.mark.asyncio
+async def test_async_json_list_paginator_raises_on_dict():
+    """
+    Test that AsyncJsonListPaginator raises TypeError when the API returns a dictionary
+    instead of the expected list.
+    """
+    client = MockAsyncClient({"error": "Async error"})
+    paginator = AsyncJsonListPaginator(client, "/path")  # type: ignore
+
+    with pytest.raises(TypeError, match="API response must be a list"):
+        [item async for item in paginator]
+
+
+@pytest.mark.asyncio
+async def test_async_json_list_paginator_raises_on_none():
+    """Test that AsyncJsonListPaginator raises TypeError when the API returns null."""
+    client = MockAsyncClient(None)
+    paginator = AsyncJsonListPaginator(client, "/path")  # type: ignore
+
+    with pytest.raises(TypeError, match="API response must be a list"):
+        [item async for item in paginator]