Replace setup.py with build

Using setup.py is no longer recommended by setuptools. Instead, projects
should use build: https://github.com/pypa/build. Invoking build will
create a source and wheel distribution
https://pypa-build.readthedocs.io/en/latest/:

> By default, a source distribution (sdist) is built from {srcdir} and a
> binary distribution (wheel) is built from the sdist.

See the setuptools quickstart guides for more information:
https://setuptools.pypa.io/en/latest/userguide/quickstart.html

> Instead, when creating new Python packages, it is recommended to use a
> command line tool called build. This tool will automatically download
> setuptools and any other build-time dependencies that your project
> might have. You just need to specify them in a pyproject.toml file at
> the root of your package, as indicated in the following section.

.github/workflows/deploy.yml

@@ -1,7 +1,7 @@
 name: "Deploy to PyPI"
 on:
   workflow_dispatch:
-    inputs: 
+    inputs:
       tag:
         description: "Git tag to deploy to PyPI"
         required: true
@@ -21,7 +21,7 @@ jobs:
       - shell: bash
         run: |
           python -m pip install --disable-pip-version-check -U pip
-          python -m pip install -U setuptools wheel twine
-          python setup.py sdist bdist_wheel
+          python -m pip install -U build twine
+          python -m build
           python -m twine check dist/*
           python -m twine upload --username=__token__ --password=${{ secrets.PYPI_TOKEN }} dist/*

.pre-commit-config.yaml

@@ -19,5 +19,4 @@ repos:
         args: ["--strict"]
         additional_dependencies: [
             "pytest==6.2.5",
-            "types-setuptools==57.4.2",
         ]

Makefile

@@ -54,7 +54,7 @@ clean:
 
 .PHONY: build
 build:
-	python setup.py sdist bdist_wheel
+	python -m build
 
 .PHONY: publish
 publish:
@@ -72,12 +72,12 @@ dev: instdev test
 .PHONY: instdev
 instdev:
 	pip install -r dev-requirements.txt
-	python setup.py develop
+	pip install -e .
 	@echo "$@ done."
 
 .PHONY: install
 install:
-	python setup.py install
+	pip install .
 	@echo "$@ done."
 
 .PHONY: clobber

pyproject.toml

@@ -0,0 +1,3 @@
+[build-system]
+requires = ["setuptools"]
+build-backend = "setuptools.build_meta"

tox.ini

@@ -15,6 +15,7 @@
 [tox]
 minversion = 1.9
 envlist = lint, py{36,37,38,39,310,py3}
+isolated_build = true
 skip_missing_interpreters = true
 
 [testenv]