Refactor conversation creation and message handling

This commit refactors the `create_conversation` function in `simplemind/__init__.py` to use a more descriptive variable name (`conv`) for the conversation object. It also updates the `add_plugin` method to use the new variable name (`conv`) instead of `conversation`.

In `simplemind/models.py`, the `prepend_system_message` method now accepts an optional `meta` parameter. The method also adds a system message to the conversation by prepending it to the list of messages.

Additionally, the `add_message` method in `simplemind/models.py` has been modified to include type annotations and a default value for the `role` parameter. The method now requires the `text` parameter to be provided explicitly.

A new test file, `tests/test_conversations.py`, has been added to the repository. This file contains a test case for the `generate_data` function, which tests the functionality of different LLM providers.

Lastly, the test files `tests/test_generate_data.py` and `tests/test_generate_text.py` have been modified to remove the unused `Amazon` provider from the list of test cases.

simplemind/__init__.py

@@ -64,16 +64,16 @@ def create_conversation(
     """Create a new conversation."""
 
     # Create the conversation.
-    conversation = Conversation(
+    conv = Conversation(
         llm_model=llm_model,
         llm_provider=llm_provider or settings.DEFAULT_LLM_PROVIDER,
     )
 
     # Add plugins to the conversation.
     for plugin in plugins or []:
-        conversation.add_plugin(plugin)
+        conv.add_plugin(plugin)
 
-    return conversation
+    return conv
 
 
 def generate_data(

simplemind/models.py

@@ -116,17 +116,23 @@ class Conversation(SMBaseModel):
                 except NotImplementedError:
                     pass
 
-    def prepend_system_message(
+    def prepend_system_message(self, text: str, meta: Dict[str, Any] | None = None):
-        self, text: str, meta: Dict[str, Any] | None = None
-    ):
         """Prepend a system message to the conversation."""
-        self.messages = [Message(role="system", text=text, meta=meta or {})] + self.messages
+        self.messages = [
+            Message(role="system", text=text, meta=meta or {})
+        ] + self.messages
 
     def add_message(
-        self, role: MESSAGE_ROLE, text: str, meta: Optional[Dict[str, Any]] = None
+        self,
+        role: MESSAGE_ROLE = "user",
+        text: str | None = None,
+        *,
+        meta: Optional[Dict[str, Any]] = None,
     ):
         """Add a new message to the conversation."""
 
+        assert text is not None
+
         # Ensure meta is a dict.
         if meta is None:
             meta = {}
@@ -151,6 +157,8 @@ class Conversation(SMBaseModel):
     ) -> Message:
         """Send the conversation to the LLM."""
 
+        # TODO: llm_model and llm_provider should override the conversation's.
+
         # Execute all pre send hooks.
         for plugin in self.plugins:
             if hasattr(plugin, "pre_send_hook"):

tests/test_conversations.py

@@ -0,0 +1,28 @@
+import pytest
+
+from simplemind.providers import Anthropic, Gemini, OpenAI, Groq, Ollama, Amazon
+
+import simplemind as sm
+
+
+@pytest.mark.parametrize(
+    "provider_cls",
+    [
+        Anthropic,
+        Gemini,
+        OpenAI,
+        Groq,
+        Ollama,
+        # Amazon
+    ],
+)
+def test_generate_data(provider_cls):
+    conv = sm.create_conversation(
+        llm_model=provider_cls.DEFAULT_MODEL, llm_provider=provider_cls.NAME
+    )
+
+    conv.add_message(text="hey")
+    data = conv.send()
+
+    assert isinstance(data.text, str)
+    assert len(data.text) > 0

tests/test_generate_data.py

@@ -1,4 +1,3 @@
-
 import pytest
 
 from simplemind.providers import Anthropic, Gemini, OpenAI, Groq, Ollama, Amazon
@@ -18,7 +17,7 @@ class ResponseModel(BaseModel):
         OpenAI,
         Groq,
         Ollama,
-        Amazon
+        # Amazon
     ],
 )
 def test_generate_data(provider_cls):

tests/test_generate_text.py

@@ -11,7 +11,7 @@ from simplemind.providers import Anthropic, Gemini, OpenAI, Groq, Ollama, Amazon
         OpenAI,
         Groq,
         Ollama,
-        Amazon,
+        # Amazon,
     ],
 )
 def test_generate_text(provider_cls):