From 163ea934ba908b150eb4b96051dbec675c171071 Mon Sep 17 00:00:00 2001
From: Joost van Zwieten <joostvanzwieten@evalf.com>
Date: Wed, 30 Nov 2022 09:56:44 +0100
Subject: [PATCH] use Flit as build system

This patch switches the build system from setuptools (using `setup.py`) to Flit
(using `pyproject.toml`).
---
 .github/workflows/release.yml |  4 +--
 .github/workflows/test.yaml   |  6 ++---
 pyproject.toml                | 27 +++++++++++++++++++
 setup.py                      | 50 -----------------------------------
 4 files changed, 32 insertions(+), 55 deletions(-)
 create mode 100644 pyproject.toml
 delete mode 100644 setup.py

diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index f7e80d0e5..34e00545f 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -11,9 +11,9 @@ jobs:
       - name: Checkout
         uses: actions/checkout@v2
       - name: Install dependencies
-        run: python3 -m pip install setuptools wheel
+        run: python3 -m pip install flit
       - name: Build package
-        run: python3 setup.py sdist bdist_wheel
+        run: python3 -m flit build
       - name: Publish package to PyPI
         uses: pypa/gh-action-pypi-publish@v1.1.0
         with:
diff --git a/.github/workflows/test.yaml b/.github/workflows/test.yaml
index 1ebc08d3e..b7e43493f 100644
--- a/.github/workflows/test.yaml
+++ b/.github/workflows/test.yaml
@@ -20,14 +20,14 @@ jobs:
       - name: Checkout
         uses: actions/checkout@v2
       - name: Install build dependencies
-        run: python3 -m pip install setuptools wheel
+        run: python3 -m pip install flit
       - name: Build package
         id: build
         run: |
           # To make the wheels reproducible, set the timestamp of the (files in
           # the) generated wheels to the date of the commit.
           export SOURCE_DATE_EPOCH=`git show -s --format=%ct`
-          python3 setup.py sdist bdist_wheel
+          python3 -m flit build
           printf "::set-output name=wheel::%s" dist/*.whl
       - name: Upload package artifacts
         uses: actions/upload-artifact@v2
@@ -156,7 +156,7 @@ jobs:
           python3 -um pip install setuptools wheel
           python3 -um pip install --upgrade --upgrade-strategy eager .[docs]
       - name: Build docs
-        run: python3 setup.py build_sphinx --nitpicky --warning-is-error --keep-going
+        run: python3 -m sphinx -n -W --keep-going docs build/sphinx/html
   build-and-test-container-image:
     name: Build container image
     needs: build-python-package
diff --git a/pyproject.toml b/pyproject.toml
new file mode 100644
index 000000000..8e9ac3ffe
--- /dev/null
+++ b/pyproject.toml
@@ -0,0 +1,27 @@
+[project]
+name = "nutils"
+readme = "README.md"
+authors = [
+    { name = "Evalf", email = "info@evalf.com" },
+]
+requires-python = '~=3.7'
+dependencies = [
+    "appdirs~=1.0",
+    "bottombar~=2.0.2",
+    "numpy>=1.17",
+    "psutil~=5.0",
+    "stringly",
+    "treelog>=1.0b5",
+]
+dynamic = ["description", "version"]
+
+[project.optional-dependencies]
+docs = ["Sphinx>=1.8"]
+export_mpl = ["matplotlib>=1.3", "pillow>2.6"]
+matrix_mkl = ["mkl"]
+matrix_scipy = ["scipy>=0.13"]
+import_gmsh = ["meshio"]
+
+[build-system]
+requires = ["flit_core >=3.2,<4"]
+build-backend = "flit_core.buildapi"
diff --git a/setup.py b/setup.py
deleted file mode 100644
index d9b7926dc..000000000
--- a/setup.py
+++ /dev/null
@@ -1,50 +0,0 @@
-import re
-import os
-from setuptools import setup
-
-long_description = """
-Nutils is a Free and Open Source Python programming library for Finite Element
-Method computations, developed by `Evalf Computing <http://evalf.com>`_ and
-distributed under the permissive MIT license. Key features are a readable, math
-centric syntax, an object oriented design, strict separation of topology and
-geometry, and high level function manipulations with support for automatic
-differentiation.
-
-Nutils provides the tools required to construct a typical simulation workflow
-in just a few lines of Python code, while at the same time leaving full
-flexibility to build novel workflows or interact with third party tools. With
-native support for Isogeometric Analysis (IGA), the Finite Cell method (FCM),
-multi-physics, mixed methods, and hierarchical refinement, Nutils is at the
-forefront of numerical discretization science. Efficient under-the-hood
-vectorization and built-in parallellisation provide for an effortless
-transition from academic research projects to full scale, real world
-applications.
-"""
-
-with open(os.path.join('nutils', '__init__.py')) as f:
-    version = next(filter(None, map(re.compile("^version = '([a-zA-Z0-9.]+)'$").match, f))).group(1)
-
-setup(
-    name='nutils',
-    version=version,
-    description='Numerical Utilities for Finite Element Analysis',
-    author='Evalf',
-    author_email='info@nutils.org',
-    url='http://nutils.org',
-    download_url='https://github.com/nutils/nutils/releases',
-    packages=['nutils', 'nutils.matrix'],
-    long_description=long_description,
-    license='MIT',
-    python_requires='>=3.7',
-    install_requires=['numpy>=1.17', 'treelog>=1.0b5', 'stringly', 'appdirs~=1.0', 'bottombar~=2.0.2', 'psutil~=5.0'],
-    extras_require=dict(
-        docs=['Sphinx>=1.8'],
-        matrix_scipy=['scipy>=0.13'],
-        matrix_mkl=['mkl'],
-        export_mpl=['matplotlib>=1.3', 'pillow>2.6'],
-        import_gmsh=['meshio'],
-    ),
-    command_options=dict(
-        test=dict(test_loader=('setup.py', 'unittest:TestLoader')),
-    ),
-)