[ci] add slotscheck (#615)

Co-authored-by: Zsolt Dollenstein <[email protected]>

Author: ariebovenberg

.github/workflows/build.yml

@@ -64,6 +64,7 @@ jobs:
     - run: flake8
     - run: ufmt check .
     - run: python3 -m fixit.cli.run_rules
+    - run: python -m slotscheck libcst
 
 # Run pyre typechecker
   typecheck:

README.rst

@@ -164,6 +164,13 @@ changes to be conformant, run the following in the root:
 
     ufmt format && python -m fixit.cli.apply_fix
 
+We use `slotscheck <https://slotscheck.rtfd.io>`_ to check the correctness
+of class ``__slots__``. To check that slots are defined properly, run:
+
+.. code-block:: shell
+
+    python -m slotscheck libcst
+
 To run all tests, you'll need to do the following in the root:
 
 .. code-block:: shell

pyproject.toml

@@ -5,5 +5,8 @@ exclude = "native/.*"
 [tool.ufmt]
 excludes = ["native/", "stubs/"]
 
+[tool.slotscheck]
+exclude-modules = '^libcst\.(testing|tests)'
+
 [build-system]
 requires = ["setuptools", "wheel", "setuptools-rust"]

requirements-dev.txt

@@ -15,3 +15,4 @@ sphinx-rtd-theme>=0.4.3
 ufmt==1.3
 usort==1.0.0rc1
 setuptools-rust>=0.12.1
+slotscheck>=0.7.1