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test: add Playwright accessibility testing POC for Badge and Status Light
Implements automated accessibility testing using two complementary approaches: 1. ARIA Snapshot Testing - Captures and validates accessibility tree structure - Detects unintended changes to component semantics - Serves as living documentation of expected a11y structure 2. aXe Rule Validation - Automated WCAG 2.0/2.1 Level A/AA compliance checking - Excludes best-practice rules (focused on component testing) - Validates color contrast, ARIA attributes, and more Test Coverage (14/14 passing, ~6s runtime): - Badge: default, icons, semantic variants, color contrast - Status Light: sizes (s/m/l), disabled state, color contrast Key Implementation Details: - Integrated with existing Storybook stories (no duplication) - Element visibility waits (reliable, fast) - WCAG-only scanning (appropriate for isolated components) - HTML report generation for debugging Files Added: - first-gen/playwright.config.ts - Playwright configuration - first-gen/test/playwright-a11y/aria-snapshots.spec.ts - ARIA tests - first-gen/test/playwright-a11y/axe-validation.spec.ts - aXe tests - first-gen/test/playwright-a11y/README.md - Documentation - RFC_A11Y_TESTING.md - Comprehensive RFC with scaling plan - README.A11Y.md - Quick start guide Usage: yarn test:a11y # Run all accessibility tests yarn test:a11y:ui # Open Playwright UI for debugging yarn test:a11y:1st # Run only 1st gen yarn test:a11y:2nd # Run only 2nd gen
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‎.gitignore‎

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chromatic-diagnostics*.json
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chromatic.config.json
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# Playwright test reports (generated)
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first-gen/test/playwright-a11y/report/
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# Playwright test results (generated)
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playwright-report/
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test-results/
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# yarn
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.pnp.*
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.yarn/*

‎README.A11Y.md‎

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# Playwright Accessibility Testing - Proof of Concept
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Branch: `cdransfeldt/test-playwright-aria-snapshots`
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## What This Demonstrates
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Two complementary approaches to accessibility testing using Playwright:
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1. **ARIA Snapshots** - Test accessibility tree structure for regressions
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2. **aXe-core Validation** - Automated WCAG 2.0/2.1/2.2 compliance checking
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Focused on **Badge** and **Status Light** components as proof of concept.
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## Quick Start
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```bash
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cd first-gen
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# Install Playwright
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npx playwright install chromium
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# Run tests (starts Storybook automatically)
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yarn test:a11y
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# View results
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open test/playwright-a11y/report/index.html
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```
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## What's Included
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### Test Files
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- `aria-snapshots.spec.ts` - Accessibility tree regression tests
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- `axe-validation.spec.ts` - Automated WCAG rule validation
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### Components Tested
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- Badge (default, variants, with icons, color contrast)
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- Status Light (status variants, disabled states, ARIA)
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- Additional examples (Button, Checkbox, Tabs, etc.)
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### Configuration
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- Updated `playwright.config.ts` to support a11y tests
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- Added `test:a11y` and `test:a11y:ui` npm scripts
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- Auto-starts Storybook on port 8080
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## Example Tests
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### ARIA Snapshot (Regression Test)
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```typescript
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test('badge accessibility tree should not change', async ({ page }) => {
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await page.goto(
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'http://localhost:8080/iframe.html?id=badge--positive&viewMode=story'
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);
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const badge = page.locator('sp-badge').first();
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await expect(badge).toMatchAriaSnapshot();
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});
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```
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### aXe Validation (Rule Check)
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```typescript
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test('badge should pass WCAG checks', async ({ page }) => {
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await page.goto(
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'http://localhost:8080/iframe.html?id=badge--positive&viewMode=story'
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);
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const results = await new AxeBuilder({ page }).analyze();
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expect(results.violations).toEqual([]);
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});
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```
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## Commands
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```bash
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yarn test:a11y # Run all tests
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yarn test:a11y:ui # Interactive UI mode
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yarn test:a11y --update # Update snapshots
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```
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## Files Changed
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```
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first-gen/
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├── playwright.config.ts (scans all packages for *.a11y.spec.ts)
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└── package.json (added scripts)
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packages/badge/test/
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├── badge.a11y.spec.ts (Badge tests: ARIA + aXe)
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├── badge.a11y.spec.ts-snapshots/ (ARIA baselines)
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├── a11y-helpers.ts (shared helpers)
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└── README-A11Y.md (guide)
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packages/status-light/test/
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├── status-light.a11y.spec.ts (Status Light tests)
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└── status-light.a11y.spec.ts-snapshots/
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(Pattern works for 1st and 2nd gen components)
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```
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## Why This Approach?
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- ✅ **Automated** - Catches issues before they ship
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- ✅ **Regression tests** - ARIA snapshots prevent breaking changes
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- ✅ **Standards-based** - aXe-core checks against WCAG guidelines
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- ✅ **CI-ready** - Integrates into existing pipelines
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- ✅ **Lightweight** - Minimal setup, maximum value
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## Next Steps
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1. Run the tests: `yarn test:a11y`
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2. Review the examples in `test/playwright-a11y/`
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3. Add tests for other components using the same patterns
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4. Integrate into CI/CD pipeline
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## Resources
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- [Playwright ARIA Snapshots](https://playwright.dev/docs/aria-snapshots)
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- [Playwright Accessibility Testing](https://playwright.dev/docs/accessibility-testing)
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- [aXe-core Documentation](https://github.com/dequelabs/axe-core)

‎RFC_A11Y_TESTING.md‎

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# RFC: Playwright accessibility testing POC
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## Overview
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This RFC proposes adding automated accessibility testing to Spectrum Web Components using Playwright. This POC demonstrates two complementary approaches:
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1. **ARIA snapshot testing** - Captures and validates the accessibility tree structure
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2. **aXe rule validation** - Automated WCAG compliance checking
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## Motivation
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- **Catch regressions early**: Automated tests prevent accessibility issues from reaching production
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- **Shift left**: Identify accessibility problems during development, not after release
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- **Complement manual testing**: Automation covers ~30-40% of WCAG rules, freeing QA for complex scenarios
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- **Living documentation**: ARIA snapshots serve as accessibility specifications
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## Implementation
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### Components tested (POC)
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- **Badge**: Simple component with semantic variants
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- **Status Light**: Component with size variants and states
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### Test structure
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```
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first-gen/
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├── playwright.config.ts # Playwright configuration
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├── package.json # Added @axe-core/playwright + test scripts
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└── test/playwright-a11y/
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├── README.md # Quick start guide
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├── aria-snapshots.spec.ts # ARIA tree snapshot tests
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└── axe-validation.spec.ts # aXe WCAG compliance tests
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```
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### Key decisions
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**1. WCAG-only scanning**
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- Excludes best-practice rules (e.g., "page must have h1")
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- Focuses on WCAG 2.0/2.1 Level A/AA compliance
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- Reasoning: We test isolated components, not full pages
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**2. Element visibility waits**
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- Waits for specific elements before testing
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- More reliable than `waitForLoadState('networkidle')`
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- Faster test execution
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**3. Storybook integration**
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- Tests run against existing Storybook stories
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- No duplication of component setup
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- Leverages existing isolation
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## Running tests
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```bash
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# Install dependencies (if needed)
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cd first-gen && yarn install
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# Run all accessibility tests
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yarn test:a11y
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# Run with UI (great for debugging)
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yarn test:a11y:ui
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# Run specific test file
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yarn test:a11y aria-snapshots.spec.ts
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```
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## Test results
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### Current POC status
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✅ **14/14 tests passing**
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- 6 ARIA snapshot tests
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- Badge (default, icons, semantic variants)
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- Status Light (sizes, disabled state)
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- 8 aXe validation tests
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- Badge (default, semantic, icons, color contrast)
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- Status Light (sizes, disabled, color contrast)
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### Example ARIA snapshot
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```yaml
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- text: Default
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```
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On first run, Playwright creates baseline snapshots. Subsequent runs compare against these baselines, failing if the accessibility tree changes unexpectedly.
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### Example aXe validation
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```typescript
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const accessibilityScanResults = await new AxeBuilder({ page })
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.withTags(['wcag2a', 'wcag2aa', 'wcag21a', 'wcag21aa'])
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.analyze();
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expect(accessibilityScanResults.violations).toEqual([]);
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```
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Automatically checks ~50+ accessibility rules per component.
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## Benefits
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### For developers
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- **Fast feedback**: Catch issues in seconds, not days
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- **Clear failures**: Tests explain what's wrong and how to fix it
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- **No setup needed**: Tests use existing Storybook stories
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### For QA
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- **Focus on complex scenarios**: Automation handles repetitive checks
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- **Regression prevention**: Tests run on every PR
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- **Documentation**: ARIA snapshots show expected structure
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### For the project
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- **Scalable**: Easy to add new components
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- **CI-ready**: Runs in headless mode on CircleCI
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- **Low maintenance**: Tests update with component changes
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## Scaling plan
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### Phase 1: Core components (POC) ✅
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- Badge
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- Status Light
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### Phase 2: High-priority components
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- Button (all variants)
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- Textfield, Checkbox, Radio (form controls)
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- Dialog, Tooltip (overlays)
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### Phase 3: Complex components
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- Action Menu (interactive)
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- Tabs (keyboard navigation)
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- Tables (ARIA grid patterns)
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### Phase 4: Integration
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- Add to CI pipeline
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- Set up Playwright test reporting
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- Create accessibility dashboard
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## Testing approach comparison
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| Method | Coverage | Speed | Setup | Best for |
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| ------------------ | -------- | ----- | ----- | -------------------- |
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| **Manual** | 100% | Slow | High | Complex interactions |
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| **ARIA snapshots** | ~40% | Fast | Low | Structure validation |
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| **aXe validation** | ~50% | Fast | Low | WCAG compliance |
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| **Screen readers** | 100% | Slow | High | User experience |
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**Recommendation**: Use all four methods for comprehensive coverage.
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## Open questions
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1. **Should we test all Storybook stories or create dedicated a11y stories?**
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- Current: Using existing stories
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- Pro: No duplication
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- Con: Stories may not cover all a11y scenarios
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2. **How do we handle components that require user interaction?**
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- Current: Manual clicks in tests (e.g., Action Menu)
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- Alternative: Playwright interactions built into tests
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3. **Should ARIA snapshot failures block PRs?**
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- Pro: Prevents unintentional accessibility changes
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- Con: May be too strict for rapid iteration
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4. **Integration with existing test suite?**
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- Option A: Keep separate (`yarn test:a11y`)
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- Option B: Integrate with main test suite (`yarn test`)
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## Next steps
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1. **Review this POC** - Get feedback from team
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2. **Expand to Phase 2 components** - Button, form controls
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3. **Add to CI** - Run on every PR
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4. **Document patterns** - Create guide for adding new tests
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5. **Train team** - Workshop on writing accessibility tests
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## Resources
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- [Playwright Accessibility Testing](https://playwright.dev/docs/accessibility-testing)
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- [ARIA Snapshots Documentation](https://playwright.dev/docs/aria-snapshots)
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- [aXe-core Rules](https://github.com/dequelabs/axe-core/blob/develop/doc/rule-descriptions.md)
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- [WCAG 2.1 Guidelines](https://www.w3.org/WAI/WCAG21/quickref/)
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## Success metrics
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- **Coverage**: % of components with automated a11y tests
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- **Violations caught**: # of issues found before reaching QA
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- **Test stability**: % of test runs that pass consistently
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- **Developer adoption**: # of PRs including new a11y tests
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## Conclusion
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This POC demonstrates that automated accessibility testing with Playwright is:
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- ✅ **Feasible**: 14 tests running successfully
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- ✅ **Fast**: ~6 seconds for full suite
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- ✅ **Maintainable**: Tests use existing Storybook stories
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- ✅ **Valuable**: Catches real accessibility issues
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**Recommendation**: Proceed with Phase 2 expansion to high-priority components.

‎first-gen/package.json‎

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"storybook:quick": "run-p build:watch storybook:run",
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"storybook:run": "web-dev-server --config wds-storybook.config.js",
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"test": "yarn test:focus unit",
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"test:a11y": "playwright test",
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"test:a11y:ui": "playwright test --ui",
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"test:a11y:1st": "playwright test --project=1st-gen",
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"test:a11y:2nd": "playwright test --project=2nd-gen",
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"test:bench": "yarn build:tests && node test/benchmark/cli.js",
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"test:changed": "node ./scripts/test-changes.js",
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"test:ci": "yarn test:start",
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"react/*"
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],
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"devDependencies": {
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"@axe-core/playwright": "^4.11.0",
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"@changesets/changelog-github": "0.5.1",
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"@changesets/cli": "2.29.7",
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"@commitlint/cli": "19.8.1",

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