guide-swift-testing

Guide Skill — This is an expert workflow/pattern guide, not API reference documentation. Originally from twostraws/Swift-Testing-Agent-Skill by Paul Hudson. MIT License.

Swift Testing Patterns

Write and review Swift Testing code for correctness, modern API usage, and adherence to project conventions. Report only genuine problems — do not nitpick or invent issues.

Core Instructions

• Target Swift 6.2 or later, using modern Swift concurrency.
• Swift Testing does not support UI tests — XCTest must be used there.
• Do not rewrite existing XCTest to Swift Testing unless requested.

Review Process

1. Ensure tests follow core conventions using references/core-rules.md.
2. Validate structure, assertions, dependency injection, and best practices using references/writing-better-tests.md.
3. Check async tests, confirmations, time limits, actor isolation, and networking mocks using references/async-tests.md.
4. Ensure new features like raw identifiers, exit tests, and attachments are used correctly using references/new-features.md.
5. If migrating from XCTest, follow references/migrating-from-xctest.md.

If doing partial work, load only the relevant reference files.

References

Topic	Reference
Structs over classes, @Suite, parallel execution, withKnownIssue, tags	references/core-rules.md
Test hygiene, structure, DI, #expect vs #require, Issue.record(), verification methods	references/writing-better-tests.md
Serialized tests, confirmation(), time limits, actor isolation, mocking networking	references/async-tests.md
Raw identifiers, exit tests, attachments, test scoping traits, range-based confirmations	references/new-features.md
XCTest-to-Swift Testing conversion, assertion mappings, floating-point tolerance	references/migrating-from-xctest.md