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BackstopJS Visual Testing

Testing & Quality
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BackstopJS visual regression testing for self-hosted visual comparison

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How to use this skill

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Source SKILL.md: https://github.com/a5c-ai/babysitter/blob/HEAD/library/specializations/qa-testing-automation/skills/backstopjs-visual/SKILL.md

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BackstopJS Visual Testing Skill

Overview

This skill provides expert-level capabilities for BackstopJS-based visual regression testing, enabling self-hosted visual comparison without external dependencies.

Capabilities

Scenario Configuration

  • Configure BackstopJS scenarios
  • Define viewport configurations
  • Set up selectors for capture
  • Configure scenario-specific settings

Reference Management

  • Execute reference runs
  • Update reference images
  • Handle reference versioning

Visual Comparison

  • Execute test runs against references
  • Analyze visual diff reports
  • Configure diff thresholds

Interaction Handling

  • Configure click and hover interactions
  • Handle scroll positions
  • Implement wait conditions
  • Execute custom scripts before capture

Report Generation

  • Generate HTML comparison reports
  • CI-friendly report formats
  • History tracking

Engine Configuration

  • Configure Puppeteer engine settings
  • Chrome launch options
  • Network request handling

Target Processes

  • visual-regression.js - Visual regression testing
  • e2e-test-suite.js - E2E with visual validation

Dependencies

  • backstopjs - Visual regression tool
  • Puppeteer (bundled)
  • Docker (optional, for consistent rendering)

Usage Example

{
  kind: 'skill',
  skill: {
    name: 'backstopjs-visual',
    context: {
      action: 'test',
      configPath: 'backstop.json',
      scenarios: ['homepage', 'dashboard'],
      viewports: ['phone', 'tablet', 'desktop']
    }
  }
}

Configuration

The skill uses backstop.json for configuration and supports Docker-based execution for consistent results.