add docstring linter and docstrings

langchain/__init__.py

@@ -0,0 +1 @@
+"""Main entrypoint into package."""

langchain/formatting.py

@@ -1,15 +1,18 @@
+"""Utilities for formatting strings."""
 from string import Formatter
 
 
 class StrictFormatter(Formatter):
     """A subclass of formatter that checks for extra keys."""
 
     def check_unused_args(self, used_args, args, kwargs):
+        """Check to see if extra parameters are passed."""
         extra = set(kwargs).difference(used_args)
         if extra:
             raise KeyError(extra)
 
     def vformat(self, format_string, args, kwargs):
+        """Check that no arguments are provided."""
         if len(args) > 0:
             raise ValueError(
                 "No arguments should be provided, "

langchain/prompt.py

@@ -13,10 +13,13 @@ class Prompt(BaseModel):
     template: str
 
     class Config:
+        """Configuration for this pydantic object."""
+
         extra = Extra.forbid
 
     @root_validator()
     def template_is_valid(cls, values: Dict) -> Dict:
+        """Check that template and input variables are consistent."""
         input_variables = values["input_variables"]
         template = values["template"]
         dummy_inputs = {input_variable: "foo" for input_variable in input_variables}

requirements.txt

@@ -4,3 +4,4 @@ black
 isort
 mypy
 flake8
+flake8-docstrings

setup.py

@@ -1,3 +1,4 @@
+"""Set up the package."""
 from setuptools import find_packages, setup
 
 with open("README.md", "r") as f:

tests/unit_tests/test_formatting.py

@@ -1,22 +1,26 @@
+"""Test formatting functionality."""
 import pytest
 
 from langchain.formatting import formatter
 
 
 def test_valid_formatting():
+    """Test formatting works as expected."""
     template = "This is a {foo} test."
     output = formatter.format(template, foo="good")
     expected_output = "This is a good test."
     assert output == expected_output
 
 
 def test_does_not_allow_args():
+    """Test formatting raises error when args are provided."""
     template = "This is a {} test."
     with pytest.raises(ValueError):
         formatter.format(template, "good")
 
 
 def test_does_not_allow_extra_kwargs():
+    """Test formatting does not allow extra key word arguments."""
     template = "This is a {foo} test."
     with pytest.raises(KeyError):
         formatter.format(template, foo="good", bar="oops")

tests/unit_tests/test_schema.py → tests/unit_tests/test_prompt.py

@@ -1,9 +1,11 @@
+"""Test functionality related to prompts."""
 import pytest
 
 from langchain.prompt import Prompt
 
 
 def test_prompt_valid():
+    """Test prompts can be constructed."""
     template = "This is a {foo} test."
     input_variables = ["foo"]
     prompt = Prompt(input_variables=input_variables, template=template)
@@ -12,20 +14,23 @@ def test_prompt_valid():
 
 
 def test_prompt_missing_input_variables():
+    """Test error is raised when input variables are not provided."""
     template = "This is a {foo} test."
     input_variables = []
     with pytest.raises(ValueError):
         Prompt(input_variables=input_variables, template=template)
 
 
 def test_prompt_extra_input_variables():
+    """Test error is raised when there are too many input variables."""
     template = "This is a {foo} test."
     input_variables = ["foo", "bar"]
     with pytest.raises(ValueError):
         Prompt(input_variables=input_variables, template=template)
 
 
 def test_prompt_wrong_input_variables():
+    """Test error is raised when name of input variable is wrong."""
     template = "This is a {foo} test."
     input_variables = ["bar"]
     with pytest.raises(ValueError):