Introduce Playwright for Component Testing

[Copilot]

Adds Playwright as a complementary testing tool for component-level integration and UI interaction testing, alongside existing Jest (unit) and Cypress (E2E) tests.

Implementation

Test Infrastructure

• Playwright configured with Chromium, auto-starting dev server, CI-optimized settings
• 11 passing tests across button and chip components
• Test scripts: npm run playwright, playwright:ui, playwright:headed, playwright:report

Testing Approach
Uses the existing composition app as test harness instead of experimental Angular component testing packages. Tests navigate to actual component pages (/button, /chip) where components render in their real context.

test('should display button with label', async ({ page }) => {
  await page.goto('/button');
  const button = page.locator('cps-button').filter({ hasText: 'Normal button' }).first();
  await expect(button).toBeVisible();
});

Documentation

• /docs/testing/playwright-approach.md - comprehensive design doc covering runner rationale, mounting strategy, directory structure, visual testing plan, and CI integration workflow
• /playwright/README.md - quick start guide
• Updated main README with Playwright section

Directory Structure

playwright/
├── components/
│   ├── cps-button.spec.ts    # 7 tests
│   └── cps-chip.spec.ts      # 4 tests
└── README.md

CI integration workflow included in design doc, ready to add to .github/workflows/cps-shared-ui-checkers.yml.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• download.cypress.io
  • Triggering command: /usr/local/bin/node node index.js --exec install (dns block)
• googlechromelabs.github.io
  • Triggering command: /usr/local/bin/node node install.mjs (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Introduce Playwright Tests</issue_title>
<issue_description>We currently have limited Cypress E2E tests. We want to introduce Playwright for component-level and integration UI tests across our Angular component library. This spike validates the approach, confirms tooling, and outlines the plan to implement and run these tests locally and in CI.

Deliverables

A short design note (in /docs/testing/playwright-approach.md) covering:

• Runner choice & rationale
• Component mounting approach
• Directory structure
• Example tests
• Visual testing plan (if any)
• CI approach

PoC branch with Playwright initialized and 1–2 green tests on a local run.
</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Introduce Playwright Tests #472

---

💡 You can make Copilot smarter by setting up custom instructions, customizing its development environment and configuring Model Context Protocol (MCP) servers. Learn more Copilot coding agent tips in the docs.

[github-actions]

Coverage report for library

St.❔	Category	Percentage	Covered / Total
🔴	Statements	29.31%	1832/6250
🔴	Branches	23.06%	482/2090
🔴	Functions	24.57%	329/1339
🔴	Lines	30.14%	1733/5749

Test suite run success

414 tests passing in 20 suites.

Report generated by 🧪jest coverage report action from fb44c1a