Require C++20 and update to C++20 #1910

	name: pre-commit

	on:
	push:
	branches:
	- master
	pull_request:
	workflow_dispatch:

	jobs:
	pre-commit:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	- uses: cvmfs-contrib/github-action-cvmfs@v4
	- uses: aidasoft/run-lcg-view@v4
	with:
	container: el9
	view-path: /cvmfs/sw-nightlies.hsf.org/key4hep
	run: \|
	echo "::group::Setup pre-commit"
	# Newer versions of git are more cautious around the github runner
	# environment and without this git rev-parse --show-cdup in pre-commit
	# fails
	git config --global --add safe.directory $(pwd)
	python -m venv /root/pre-commit-venv
	source /root/pre-commit-venv/bin/activate
	pip install pre-commit
	pip install pylint==2.17.7
	pip install flake8
	export PYTHONPATH=$VIRTUAL_ENV/lib/python3.$(python3 -c 'import sys; print(f"{sys.version_info[1]}")')/site-packages:$PYTHONPATH
	echo "::endgroup::"
	echo "::group::Run CMake"
	mkdir build
	cd build
	cmake .. -DENABLE_SIO=ON \
	-DENABLE_JULIA=ON \
	-DENABLE_RNTUPLE=ON \
	-DENABLE_DATASOURCE=ON \
	-DCMAKE_CXX_STANDARD=20 \
	-DCMAKE_CXX_FLAGS=" -fdiagnostics-color=always -Werror "\
	-DCMAKE_EXPORT_COMPILE_COMMANDS=ON \
	-DUSE_EXTERNAL_CATCH2=OFF
	ln -s $(pwd)/compile_commands.json ../
	cd ..
	echo "::endgroup::"
	echo "::group::Run pre-commit"
	pre-commit run --show-diff-on-failure \
	--color=always \
	--all-files
	echo "::endgroup::"

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