Merge pull request #341 from sjrd/visual-identity #396

	name: CI

	on:
	push:
	branches:
	- main
	pull_request:
	branches:
	- main

	jobs:
	build:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	- uses: ruby/setup-ruby@v1
	with:
	ruby-version: '3.2.3'
	bundler-cache: true
	- name: Bower
	run: \|
	npm install -g bower
	bower install
	- name: Build site
	run: \|
	bundle exec jekyll build 2> error.log
	cat >&2 error.log
	( ! grep -qie Error -e Warn error.log )
	- name: Cache HTMLProofer
	id: cache-htmlproofer
	uses: actions/cache@v4
	with:
	path: tmp/.htmlproofer
	key: ${{ runner.os }}-htmlproofer
	- name: HTMLProofer
	run: \|
	# Check all links
	# Don't check links to twitter.com because they return 400 all the time
	# Also ignore github.com because we have too many and they eventually return 429
	bundle exec htmlproofer ./_site/\
	--only-4xx\
	--ignore-empty-alt\
	--allow-hash-href\
	--no-enforce-https\
	--ignore-missing-alt\
	--swap-urls "https\:\/\/scala\.epfl\.ch:"\
	--ignore-urls "/twitter.com/,/x.com/,/github.com/"\
	--cache '{ "timeframe": { "external": "30d" } }'

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