qa-visual-ios

name	qa-visual-ios
description	Visual QA for iOS apps using swift-snapshot-testing. Validates UIKit/SwiftUI views render correctly across devices and traits.

qa-visual-ios - iOS Visual QA

Visual regression testing for iOS applications using swift-snapshot-testing.

Input Schema

{
  "project_dir": "/path/to/ios_project",
  "ticket_id": "TICKET-XXX",
  "test_target": "MyAppTests",
  "devices": ["iPhone14", "iPadPro"],
  "traits": ["light", "dark", "accessibility"],
  "record_mode": false
}

Prerequisites

// Package.swift or SPM
dependencies: [
  .package(url: "https://github.com/pointfreeco/swift-snapshot-testing", from: "1.12.0")
]

Instructions

1. Run Snapshot Tests

cd $project_dir
xcodebuild test \
  -scheme MyApp \
  -destination 'platform=iOS Simulator,name=iPhone 14' \
  -only-testing:MyAppTests/SnapshotTests

2. Test Structure

// MyViewSnapshotTests.swift
import XCTest
import SnapshotTesting
@testable import MyApp

class MyViewSnapshotTests: XCTestCase {

  func testMyView_iPhone14() {
    let view = MyView()
    assertSnapshot(matching: view, as: .image(on: .iPhone14))
  }

  func testMyView_darkMode() {
    let view = MyView()
    assertSnapshot(matching: view, as: .image(on: .iPhone14, traits: .init(userInterfaceStyle: .dark)))
  }

  func testMyView_accessibility() {
    let view = MyView()
    assertSnapshot(matching: view, as: .image(on: .iPhone14, traits: .init(preferredContentSizeCategory: .accessibilityLarge)))
  }
}

3. SwiftUI Testing

func testSwiftUIView() {
  let view = ContentView()
  let hostingController = UIHostingController(rootView: view)
  hostingController.view.frame = UIScreen.main.bounds

  assertSnapshot(matching: hostingController, as: .image(on: .iPhone14))
}

4. Multi-Device Testing

func testMyView_allDevices() {
  let view = MyView()

  assertSnapshot(matching: view, as: .image(on: .iPhoneSe))
  assertSnapshot(matching: view, as: .image(on: .iPhone14))
  assertSnapshot(matching: view, as: .image(on: .iPhone14ProMax))
  assertSnapshot(matching: view, as: .image(on: .iPadPro12_9))
}

Output Format

{
  "skill": "qa-visual-ios",
  "status": "pass|fail",
  "tests": {
    "total": 12,
    "passed": 10,
    "failed": 2
  },
  "failures": [
    {
      "test": "testMyView_darkMode",
      "expected": "__Snapshots__/MyViewTests/testMyView_darkMode.png",
      "actual": "__Snapshots__/MyViewTests/testMyView_darkMode.actual.png",
      "diff_percent": 3.1,
      "category": "color_diff"
    }
  ],
  "devices_tested": ["iPhoneSe", "iPhone14", "iPadPro12_9"],
  "traits_tested": ["light", "dark", "accessibilityLarge"],
  "next_action": "proceed|fix|record"
}

Failure Categories

Category	Description	Common Cause
layout_diff	View frame/bounds changed	Auto Layout changes
color_diff	Colors don't match	Theme/asset changes
text_diff	Text rendering different	Font/localization
missing_subview	Subview not rendered	Visibility logic bug
safe_area	Safe area insets wrong	Device-specific issue

Decision Logic

Any test failed?
    YES → Check diff_percent
        > 5% → status: "fail", next_action: "fix"
        1-5% → status: "warning", manual review
        < 1% → likely rendering variance, pass

Record mode requested?
    YES → Update reference snapshots

Usage Examples

Basic snapshot test:

{
  "project_dir": "/projects/MyiOSApp",
  "ticket_id": "TICKET-IOS-001"
}

Record new baselines:

{
  "project_dir": "/projects/MyiOSApp",
  "ticket_id": "TICKET-IOS-001",
  "record_mode": true
}

Token Efficiency

• Uses xcodebuild test runner
• Binary image comparison
• Returns structured results
• ~30-60 second execution