Add pyproject.toml and drop support for python < 3.8 (#101)

* add pyproject.toml

* clean up setup.py for py3.8 minimum

* update CI

* remove packaging

* add wheel build

* add in runtime deps

* try python3 kludge

* change shell to pickup right python version

* revert python3 kludging

* add activate step

* Revert "add activate step"

This reverts commit 5e74c6e.

* change shell for each setup

* remove defaulkt shell

* delete empty

* split shell defaults

* Update pyproject.toml

Co-authored-by: Irfan Alibay <IAlibay@users.noreply.github.com>

* add install and setup_requires

* remove print_function

* remove pip install of reqs

Co-authored-by: Irfan Alibay <IAlibay@users.noreply.github.com>

Author: hmacdope

.github/workflows/build.yml

@@ -17,22 +17,21 @@ concurrency:
   group: "${{ github.ref }}-${{ github.head_ref }}-${{ github.workflow }}"
   cancel-in-progress: true
 
-defaults:
-  run:
-    shell: bash -l {0}
-
 jobs:
   build:
+    defaults:
+      run:
+        shell: bash -l {0}
     runs-on: ${{matrix.os}}
     strategy:
       max-parallel: 12
       fail-fast: false
       matrix:
         os: [ubuntu-latest, macos-latest, windows-latest]
-        python-version: ['3.6', '3.7', '3.8', '3.9', '3.10', '3.11']
+        python-version: ['3.8', '3.9', '3.10', '3.11']
 
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v3
     - name: Setup Miniconda
       uses: conda-incubator/setup-miniconda@v2
       with:
@@ -47,3 +46,37 @@ jobs:
     - name: Test with pytest
       run: |
         pytest -v -ra ./tests/
+
+
+  pip-install:
+    # A pure Python install, which relies purely on pyproject.toml contents
+    defaults:
+      run:
+        shell: bash {0}
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu-latest, macos-latest, windows-latest]
+        python: ["3.8", "3.9", "3.10", "3.11"]
+
+    steps:
+    - uses: actions/checkout@v3
+
+    - uses: actions/setup-python@v4
+      with:
+        python-version: ${{ matrix.python }}
+
+    - name: check_env
+      run: |
+        which python
+        python -m pip list
+    - name: build
+      run: python -m pip -v install .
+
+    - name: install_reqs
+      run: pip install pytest
+
+    - name: pytests
+      run: |
+        pytest -v -ra ./tests/

pyproject.toml

@@ -0,0 +1,20 @@
+[build-system]
+# Minimum requirements for the build system to execute
+requires = [
+    "cython>=0.28,<3.0",
+    "setuptools",
+    "wheel",
+    # below matches MDA
+    "numpy==1.20.0; python_version=='3.8' and (platform_machine!='arm64' or platform_system!='Darwin') and platform_python_implementation != 'PyPy'",
+    "numpy==1.20.0; python_version=='3.9' and (platform_machine!='arm64' or platform_system!='Darwin') and platform_python_implementation != 'PyPy'",
+    # arm64 on darwin for py3.8+ requires numpy >=1.21.0
+    "numpy==1.21.0; python_version=='3.8' and platform_machine=='arm64' and platform_system=='Darwin' and platform_python_implementation != 'PyPy'",
+    "numpy==1.21.0; python_version=='3.9' and platform_machine=='arm64' and platform_system=='Darwin' and platform_python_implementation != 'PyPy'",
+    # Scipy: On windows avoid 1.21.6, 1.22.0, and 1.22.1 because they were built on vc142
+    "numpy==1.22.3; python_version=='3.10' and platform_system=='Windows' and platform_python_implementation != 'PyPy'",
+    # As per https://github.com/scipy/oldest-supported-numpy/blob/main/setup.cfg
+    # safest to build at 1.21.6 for all other platforms
+    "numpy==1.21.6; python_version=='3.10' and platform_system !='Windows'and platform_python_implementation != 'PyPy'",
+    "numpy==1.23.2; python_version=='3.11' and platform_python_implementation != 'PyPy'",
+    "numpy<2.0; python_version>='3.12'",
+]

setup.cfg

@@ -4,4 +4,11 @@ style = pep440
 versionfile_source = pytng/_version.py
 versionfile_build = pytng/_version.py
 tag_prefix =
-parentdir_prefix = pytng-
+parentdir_prefix = pytng-
+
+[options]
+setup_requires =
+    numpy>=1.20.0
+    cython>=0.28,<3.0
+install_requires =
+    numpy>=1.20.0

setup.py

@@ -1,19 +1,10 @@
-from __future__ import print_function
-
 import os
 import sys
 import versioneer
 from glob import glob
 
 from setuptools import setup, Command, Extension
 
-# Make sure I have the right Python version.
-if sys.version_info[:2] < (3, 6):
-    print('MDAnalysis requires Python 3.6 or better. Python {0:d}.{1:d} detected'.format(*
-          sys.version_info[:2]))
-    print('Please upgrade your version of Python.')
-    sys.exit(-1)
-
 try:
     import numpy as np
 except ImportError:
@@ -71,7 +62,7 @@ def extensions():
 
 setup(
     name="pytng",
-    python_requires=">=3.6",
+    python_requires=">=3.8",
     version=versioneer.get_version(),
     description='Minimal Cython wrapper of the TNG trajectory library',
     long_description=long_description,