Migrate added test cases of String #759

	name: CI

	on: [push, pull_request]

	jobs:
	unit-test:
	name: unit tests
	runs-on: ubuntu-latest
	container:
	image: amutake/satysfi:opam-slim
	steps:
	- uses: actions/checkout@v1
	- name: Install Satyrographos dependencies
	run: \|
	export HOME=/root
	eval $(opam env)
	opam update
	opam pin add --verbose --yes "."
	satyrographos install -l base
	- name: Run tests
	run: \|
	export HOME=/root
	eval $(opam env)
	cd test && sh run-test.sh -v
	- if: always()
	name: Install Apt dependencies
	run: apt-get update && apt-get install -y xz-utils liblzma-dev
	- name: Upload artifact
	uses: actions/upload-artifact@master
	with:
	name: satysfi-test-report
	path: test/report.txt
	regression-test:
	name: Regression tests
	runs-on: ubuntu-latest
	container:
	image: zeptometer/satysfi-yarn-diff-pdf:latest
	strategy:
	matrix:
	satysfi-version:
	[
	0.0.5,
	0.0.6,
	0.0.7,
	]
	steps:
	- uses: actions/checkout@v1
	- name: Install Yarn dependencies
	run: yarn install
	- name: Install Satyrographos dependencies
	run: \|
	export HOME=/root
	eval $(opam env)
	opam update
	opam pin add satysfi ${{ matrix.satysfi-version }}
	opam pin add --verbose --yes "."
	satyrographos install -l base
	- name: Run regression tests
	run: \|
	export HOME=/root
	eval $(opam env)
	yarn test --ci

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