Update version to 5.4.1 and add docstring validation for decorated functions

- Bump version to 5.4.1 to reflect recent changes
- Implement validation to raise TypeError for functions without docstrings or with f-string docstrings
- Add tests to ensure proper error handling for docstring validation

Author: knowsuchagency

promptic.py

@@ -17,7 +17,7 @@
 from litellm import completion as litellm_completion
 from pydantic import BaseModel
 
-__version__ = "5.4.0"
+__version__ = "5.4.1"
 
 SystemPrompt = Optional[Union[str, List[str], List[Dict[str, str]]]]
 
@@ -446,7 +446,13 @@ def wrapper(*args, **kwargs):
             )
 
             # Get the function's docstring as the prompt
-            prompt_template = dedent(func.__doc__)
+            try:
+                prompt_template = dedent(func.__doc__)
+            except TypeError as e:
+                raise TypeError(
+                    f"Function {func.__name__} has no docstring. "
+                    "Ensure the docstring is not an f-string."
+                ) from e
 
             # Get the argument names, default values and values using inspect
             sig = inspect.signature(func)

tests/test_promptic.py

@@ -1711,3 +1711,39 @@ def update_user(profile: UserProfile) -> str:
     )
 
     assert name == "John Doe"
+
+
+@pytest.mark.parametrize("model", CHEAP_MODELS[:1])
+@pytest.mark.parametrize(
+    "create_completion_fn", [openai_completion_fn, litellm_completion][:1]
+)
+def test_docstring_validation(model, create_completion_fn):
+    """Test validation of docstrings in decorated functions"""
+    if create_completion_fn == openai_completion_fn and not model.startswith("gpt"):
+        pytest.skip("Non-GPT models are not supported with OpenAI client")
+
+    # Test function with no docstring
+    with pytest.raises(TypeError) as exc_info:
+
+        @llm(model=model, create_completion_fn=create_completion_fn)
+        def no_docstring_function(text):
+            pass
+
+        no_docstring_function("Hello")
+
+    assert "no_docstring_function has no docstring" in str(exc_info.value)
+    assert "Ensure the docstring is not an f-string" in str(exc_info.value)
+
+    # Test function with an f-string (this won't actually be executed but will fail at definition time)
+    name = "World"
+    with pytest.raises(TypeError) as exc_info:
+        # This would fail because f-strings aren't allowed in docstrings
+        @llm(model=model, create_completion_fn=create_completion_fn)
+        def f_string_docstring(text):
+            f"""Hello {name}"""
+            return text
+
+        f_string_docstring("Hello")
+
+    assert "f_string_docstring has no docstring" in str(exc_info.value)
+    assert "Ensure the docstring is not an f-string" in str(exc_info.value)