Refine test matrix generation. #427

	name: Test Ubuntu

	on: [push, pull_request]

	jobs:
	build:
	runs-on: ubuntu-latest

	strategy:
	fail-fast: false
	matrix:
	python-version: [2.7, 3.9, 3.10, 3.11, 3.12, 3.13, 3.14, 3.14t]
	cxx: [g++, clang++]
	#cxx: [g++]
	#std: [c++98, c++11, c++14, c++17]
	#std: [c++17]
	include:
	# Add the appropriate docker image for each compiler.
	# The images from teeks99/boost-python-test already have boost::python
	# pre-reqs installed, see:
	# https://github.com/teeks99/boost-python-test-docker
	- cxx: clang++
	docker-img: teeks99/boost-python-test:clang-12_1.76.0
	- cxx: g++
	docker-img: teeks99/boost-python-test:gcc-10_1.76.0
	# by default, all builds use -std=c++17
	- std: c++17
	# expand test coverage for python 2.7
	- python-version: 2.7
	std: c++98
	- python-version: 2.7
	std: c++11
	- python-version: 2.7
	std: c++14

	container:
	image: ${{ matrix.docker-img }}

	steps:
	- uses: actions/checkout@v5
	- name: setup python
	if: "${{ matrix.python-version != '2.7' }}"
	uses: actions/setup-python@v6
	with:
	python-version: ${{ matrix.python-version }}
	- name: build
	run: \|
	echo ${{ matrix.python-version }} ${{ matrix.cxx }} ${{ matrix.std }}
	python --version
	${{ matrix.cxx }} --version

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