improve addition churn test readability, and add removal tests as well. #158

	name: CI

	on: [push, pull_request]

	jobs:
	test:
	runs-on: ubuntu-latest
	steps:
	- name: Checkout code
	uses: actions/checkout@v4
	- name: Use Node.js
	uses: actions/setup-node@v4
	with:
	cache: 'npm'
	- name: Install dependencies
	run: npm install
	- name: Install browsers
	run: npx playwright install --with-deps
	- name: Run tests
	run: npm run ci

	test-move-before:
	runs-on: ubuntu-latest
	steps:
	- name: Checkout code
	uses: actions/checkout@v4
	- name: Use Node.js
	uses: actions/setup-node@v4
	with:
	cache: 'npm'
	- name: Install dependencies
	run: npm install
	- name: Run tests
	run: npm run test:move-before

	coverage:
	runs-on: ubuntu-latest
	steps:
	- name: Checkout code
	uses: actions/checkout@v4
	- name: Use Node.js
	uses: actions/setup-node@v4
	with:
	cache: 'npm'
	- name: Install dependencies
	run: npm install
	- name: Install browsers
	run: npx playwright install --with-deps
	- name: Run tests
	run: npm run test:coverage
	- name: Upload coverage report
	if: always()
	uses: actions/upload-artifact@v4
	with:
	name: coverage-report
	path: coverage/

	typecheck:
	runs-on: ubuntu-latest
	steps:
	- name: Checkout code
	uses: actions/checkout@v4
	- name: Use Node.js
	uses: actions/setup-node@v4
	with:
	cache: 'npm'
	- name: Install dependencies
	run: npm install
	- name: Run typecheck
	run: npm run typecheck

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