Added LiteLLM to the stack

Development/litellm/tests/test_litellm/llms/openrouter/chat/test_openrouter_chat_transformation.py

@@ -0,0 +1,116 @@
+import os
+import sys
+
+import pytest
+
+sys.path.insert(
+    0, os.path.abspath("../../../../..")
+)  # Adds the parent directory to the system path
+
+from litellm.llms.openrouter.chat.transformation import (
+    OpenRouterChatCompletionStreamingHandler,
+    OpenrouterConfig,
+    OpenRouterException,
+)
+
+
+class TestOpenRouterChatCompletionStreamingHandler:
+    def test_chunk_parser_successful(self):
+        handler = OpenRouterChatCompletionStreamingHandler(
+            streaming_response=None, sync_stream=True
+        )
+
+        # Test input chunk
+        chunk = {
+            "id": "test_id",
+            "created": 1234567890,
+            "model": "test_model",
+            "usage": {"prompt_tokens": 10, "completion_tokens": 20, "total_tokens": 30},
+            "choices": [
+                {"delta": {"content": "test content", "reasoning": "test reasoning"}}
+            ],
+        }
+
+        # Parse chunk
+        result = handler.chunk_parser(chunk)
+
+        # Verify response
+        assert result.id == "test_id"
+        assert result.object == "chat.completion.chunk"
+        assert result.created == 1234567890
+        assert result.model == "test_model"
+        assert result.usage.prompt_tokens == chunk["usage"]["prompt_tokens"]
+        assert result.usage.completion_tokens == chunk["usage"]["completion_tokens"]
+        assert result.usage.total_tokens == chunk["usage"]["total_tokens"]
+        assert len(result.choices) == 1
+        assert result.choices[0]["delta"]["reasoning_content"] == "test reasoning"
+
+    def test_chunk_parser_error_response(self):
+        handler = OpenRouterChatCompletionStreamingHandler(
+            streaming_response=None, sync_stream=True
+        )
+
+        # Test error chunk
+        error_chunk = {
+            "error": {
+                "message": "test error",
+                "code": 400,
+                "metadata": {"key": "value"},
+                "user_id": "test_user",
+            }
+        }
+
+        # Verify error handling
+        with pytest.raises(OpenRouterException) as exc_info:
+            handler.chunk_parser(error_chunk)
+
+        assert "Message: test error" in str(exc_info.value)
+        assert exc_info.value.status_code == 400
+
+    def test_chunk_parser_key_error(self):
+        handler = OpenRouterChatCompletionStreamingHandler(
+            streaming_response=None, sync_stream=True
+        )
+
+        # Test invalid chunk missing required fields
+        invalid_chunk = {"incomplete": "data"}
+
+        # Verify KeyError handling
+        with pytest.raises(OpenRouterException) as exc_info:
+            handler.chunk_parser(invalid_chunk)
+
+        assert "KeyError" in str(exc_info.value)
+        assert exc_info.value.status_code == 400
+
+
+def test_openrouter_extra_body_transformation():
+    transformed_request = OpenrouterConfig().transform_request(
+        model="openrouter/deepseek/deepseek-chat",
+        messages=[{"role": "user", "content": "Hello, world!"}],
+        optional_params={"extra_body": {"provider": {"order": ["DeepSeek"]}}},
+        litellm_params={},
+        headers={},
+    )
+
+    # https://github.com/BerriAI/litellm/issues/8425, validate its not contained in extra_body still
+    assert transformed_request["provider"]["order"] == ["DeepSeek"]
+    assert transformed_request["messages"] == [
+        {"role": "user", "content": "Hello, world!"}
+    ]
+
+
+def test_openrouter_cache_control_flag_removal():
+    transformed_request = OpenrouterConfig().transform_request(
+        model="openrouter/deepseek/deepseek-chat",
+        messages=[
+            {
+                "role": "user",
+                "content": "Hello, world!",
+                "cache_control": {"type": "ephemeral"},
+            }
+        ],
+        optional_params={},
+        litellm_params={},
+        headers={},
+    )
+    assert transformed_request["messages"][0].get("cache_control") is None