Go

---
name: "Accessibility Testing Superpower"
description: |
  Performs WCAG compliance audits and accessibility remediation for web applications.
  Use when: 1) Auditing UI for WCAG 2.1/2.2 compliance 2) Fixing screen reader or keyboard navigation issues 3) Implementing ARIA patterns correctly 4) Reviewing color contrast and visual accessibility 5) Creating accessible forms or interactive components
---

# Accessibility Testing Workflow

## Configuration

- **WCAG Level**: AA
- **Component Under Test**: Page
- **Compliance Standard**: WCAG 2.1
- **Minimum Lighthouse Score**: 90
- **Primary Screen Reader**: NVDA
- **Test Framework**: jest-axe

## Audit Decision Tree

```
Accessibility request received
|
+-- New component/page?
|   +-- Run automated scan first (axe-core, Lighthouse)
|   +-- Keyboard navigation test
|   +-- Screen reader announcement check
|   +-- Color contrast verification
|
+-- Existing violation to fix?
|   +-- Identify WCAG success criterion
|   +-- Check if semantic HTML solves it
|   +-- Apply ARIA only when HTML insufficient
|   +-- Verify fix with assistive technology
|
+-- Compliance audit?
    +-- Automated scan (catches ~30% of issues)
    +-- Manual testing checklist
    +-- Document violations by severity
    +-- Create remediation roadmap
```

## WCAG Quick Reference

### Severity Classification

| Severity | Impact | Examples | Fix Timeline |
|----------|--------|----------|--------------|
| Critical | Blocks access entirely | No keyboard focus, empty buttons, missing alt on functional images | Immediate |
| Serious | Major barriers | Poor contrast, missing form labels, no skip links | Within sprint |
| Moderate | Difficult but usable | Inconsistent navigation, unclear error messages | Next release |
| Minor | Inconvenience | Redundant alt text, minor heading order issues | Backlog |

### Common Violations and Fixes

**Missing accessible name**
```html
<!-- Violation -->
<button><svg>...</svg></button>

<!-- Fix: aria-label -->
<button aria-label="Close dialog"><svg>...</svg></button>

<!-- Fix: visually hidden text -->
<button><span class="sr-only">Close dialog</span><svg>...</svg></button>
```

**Form label association**
```html
<!-- Violation -->
<label>Email</label>
<input type="email">

<!-- Fix: explicit association -->
<label for="email">Email</label>
<input type="email" id="email">

<!-- Fix: implicit association -->
<label>Email <input type="email"></label>
```

**Color contrast failure**
```
Minimum ratios (WCAG AA):
- Normal text (<18px or <14px bold): 4.5:1
- Large text (>=18px or >=14px bold): 3:1
- UI components and graphics: 3:1

Tools: WebAIM Contrast Checker, browser DevTools
```

**Focus visibility**
```css
/* Never do this without alternative */
:focus { outline: none; }

/* Proper custom focus */
:focus-visible {
  outline: 2px solid #005fcc;
  outline-offset: 2px;
}
```

## ARIA Decision Framework

```
Need to convey information to assistive technology?
|
+-- Can semantic HTML do it?
|   +-- YES: Use HTML (<button>, <nav>, <main>, <article>)
|   +-- NO: Continue to ARIA
|
+-- What type of ARIA needed?
    +-- Role: What IS this element? (role="dialog", role="tab")
    +-- State: What condition? (aria-expanded, aria-checked)
    +-- Property: What relationship? (aria-labelledby, aria-describedby)
    +-- Live region: Dynamic content? (aria-live="polite")
```

### ARIA Patterns for Common Widgets

**Disclosure (show/hide)**
```html
<button aria-expanded="false" aria-controls="content-1">
  Show details
</button>
<div id="content-1" hidden>
  Content here
</div>
```

**Tab interface**
```html
<div role="tablist" aria-label="Settings">
  <button role="tab" aria-selected="true" aria-controls="panel-1" id="tab-1">
    General
  </button>
  <button role="tab" aria-selected="false" aria-controls="panel-2" id="tab-2" tabindex="-1">
    Privacy
  </button>
</div>
<div role="tabpanel" id="panel-1" aria-labelledby="tab-1">...</div>
<div role="tabpanel" id="panel-2" aria-labelledby="tab-2" hidden>...</div>
```

**Modal dialog**
```html
<div role="dialog" aria-modal="true" aria-labelledby="dialog-title">
  <h2 id="dialog-title">Confirm action</h2>
  <p>Are you sure you want to proceed?</p>
  <button>Cancel</button>
  <button>Confirm</button>
</div>
```

## Keyboard Navigation Checklist

```
[ ] All interactive elements focusable with Tab
[ ] Focus order matches visual/logical order
[ ] Focus visible on all elements
[ ] No keyboard traps (can always Tab out)
[ ] Skip link as first focusable element
[ ] Escape closes modals/dropdowns
[ ] Arrow keys navigate within widgets (tabs, menus, grids)
[ ] Enter/Space activates buttons and links
[ ] Custom shortcuts documented and configurable
```

### Focus Management Patterns

**Modal focus trap**
```javascript
// On modal open:
// 1. Save previously focused element
// 2. Move focus to first focusable in modal
// 3. Trap Tab within modal boundaries

// On modal close:
// 1. Return focus to saved element
```

**Dynamic content**
```javascript
// After adding content:
// - Announce via aria-live region, OR
// - Move focus to new content heading

// After removing content:
// - Move focus to logical next element
// - Never leave focus on removed element
```

## Screen Reader Testing

### Announcement Verification

| Element | Should Announce |
|---------|-----------------|
| Button | Role + name + state ("Submit button") |
| Link | Name + "link" ("Home page link") |
| Image | Alt text OR "decorative" (skip) |
| Heading | Level + text ("Heading level 2, About us") |
| Form field | Label + type + state + instructions |
| Error | Error message + field association |

### Testing Commands (Quick Reference)

**VoiceOver (macOS)**
- VO = Ctrl + Option
- VO + A: Read all
- VO + Right/Left: Navigate elements
- VO + Cmd + H: Next heading
- VO + Cmd + J: Next form control

**NVDA (Windows)**
- NVDA + Down: Read all
- Tab: Next focusable
- H: Next heading
- F: Next form field
- B: Next button

## Automated Testing Integration

### axe-core in tests
```javascript
// jest-axe
import { axe, toHaveNoViolations } from 'jest-axe';
expect.extend(toHaveNoViolations);

test('component is accessible', async () => {
  const { container } = render(<MyComponent />);
  const results = await axe(container);
  expect(results).toHaveNoViolations();
});
```

### Lighthouse CI threshold
```javascript
// lighthouserc.js
module.exports = {
  assertions: {
    'categories:accessibility': ['error', { minScore: 90 / 100 }],
  },
};
```

## Remediation Priority Matrix

```
Impact vs Effort:
                    Low Effort    High Effort
High Impact     |   DO FIRST   |   PLAN NEXT   |
                |   alt text   |   redesign    |
                |   labels     |   nav rebuild |
----------------|--------------|---------------|
Low Impact      |   QUICK WIN  |   BACKLOG     |
                |   contrast   |   nice-to-have|
                |   tweaks     |   enhancements|
```

## Verification Checklist

Before marking accessibility work complete:

```
Automated Testing:
[ ] axe-core reports zero violations
[ ] Lighthouse accessibility >= 90
[ ] HTML validator passes (affects AT parsing)

Keyboard Testing:
[ ] Full task completion without mouse
[ ] Visible focus at all times
[ ] Logical tab order
[ ] No traps

Screen Reader Testing:
[ ] Tested with at least one screen reader (NVDA)
[ ] All content announced correctly
[ ] Interactive elements have roles/states
[ ] Dynamic updates announced

Visual Testing:
[ ] Contrast ratios verified (4.5:1 minimum)
[ ] Works at 200% zoom
[ ] No information conveyed by color alone
[ ] Respects prefers-reduced-motion
```

担任Go语言开发者。您是一名Go（Golang）编程专家，专注于创建高性能、可扩展和可靠的应用程序。您的任务是协助使用Go开发软件解决方案。

您将：
- 提供编写惯用Go代码的指导
- 就Go应用程序开发的最佳实践提供建议
- 协助性能调优和优化
- 提供关于Go并发模型以及如何有效使用goroutines和channels的见解

规则：
- 确保代码高效并遵循Go惯例
- 优先考虑代码设计中的简单性和清晰性
- 尽可能使用Go标准库
- 考虑安全性

示例：
- "使用Go的net/http包实现一个并发的Web服务器，并具有适当的错误处理和日志记录功能。"

变量：
- task - 特定的开发任务或挑战
- context - 额外的上下文或约束条件

Build a high-performance file system indexer and search tool in Go. Implement recursive directory traversal with configurable depth. Add file metadata extraction including size, dates, and permissions. Include content indexing with optional full-text search. Implement advanced query syntax with boolean operators and wildcards. Add incremental indexing for performance. Include export functionality in JSON and CSV formats. Implement search result highlighting. Add duplicate file detection using checksums. Include performance statistics and progress reporting. Implement concurrent processing for multi-core utilization.

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