Install pre-commit automatically (#763)

* install pre-commit automatically

* add to build reqs

CONTRIBUTING.rst

@@ -27,7 +27,7 @@ steps::
     pip install --upgrade setuptools pip
     git clone https://github.com/jupyter/jupyter_server
     cd jupyter_server
-    pip install -e .
+    pip install -e ".[test]"
 
 If you are using a system-wide Python installation and you only want to install the server for you,
 you can add ``--user`` to the install commands.
@@ -44,7 +44,10 @@ Code Styling
 need to worry too much about your code style.
 As long as your code is valid,
 the pre-commit hook should take care of how it should look.
-To install `pre-commit`, run the following::
+`pre-commit` and its associated hooks will automatically be installed when
+you run ``pip install -e ".[test]"``
+
+To install ``pre-commit`` manually, run the following::
 
     pip install pre-commit
     pre-commit install

pyproject.toml

@@ -1,5 +1,5 @@
 [build-system]
-requires = ["jupyter_packaging~=0.9"]
+requires = ["jupyter_packaging~=0.9", "pre-commit"]
 build-backend = "jupyter_packaging.build_api"
 
 [tool.jupyter-packaging.builder]

setup.cfg

@@ -57,6 +57,7 @@ test =
     pytest-tornasync
     pytest-console-scripts
     ipykernel
+    pre-commit
     # NOTE: we cannot auto install examples/simple here because of:
     # https://github.com/pypa/pip/issues/6658
 

setup.py

@@ -1,10 +1,24 @@
+import subprocess
+import sys
+
 from setuptools import setup
 
 try:
     from jupyter_packaging import npm_builder, wrap_installers
 
     ensured_targets = ["jupyter_server/static/style/bootstrap.min.css"]
-    cmdclass = wrap_installers(pre_develop=npm_builder(), ensured_targets=ensured_targets)
+
+    def post_develop(*args, **kwargs):
+        npm_builder()
+        try:
+            subprocess.run([sys.executable, "-m", "pre_commit", "install"])
+            subprocess.run(
+                [sys.executable, "-m", "pre_commit", "install", "--hook-type", "pre-push"]
+            )
+        except Exception:
+            pass
+
+    cmdclass = wrap_installers(post_develop=post_develop, ensured_targets=ensured_targets)
 except ImportError:
     cmdclass = {}