ci: Add a GitHub workflow for CI. #10

	name: CI
	on:
	push:
	# Filter on branch so we don't double-run this workflow on a PR's push.
	tags:
	- v*
	branches:
	- main
	pull_request:

	permissions:
	# "none-all", which doesn't exist, but
	# https://docs.github.com/en/actions/reference/authentication-in-a-workflow#using-the-github_token-in-a-workflow
	# implies that the token still gets created. Elsewhere we learn that any
	# permission not mentioned here gets turned to `none`. So this removes all permissions.
	actions: none

	jobs:
	test:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout
	- name: install dependencies
	run: sudo apt-get install -y flex bison
	- name: build
	run: ./configure --enable-gcov && make all
	- name: test
	run: make check
	- uses: codecov/codecov-action@3
	if: always()
	with:
	gcov: true
	directory: .

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