bc-wallet-mobile: Skill for Claude Code

bcsc-core Native Unit Testing

Overview

This skill guides creation of native unit tests for the packages/bcsc-core module, which contains Swift (iOS) and Kotlin (Android) implementations of authentication, PIN management, keychain storage, token services, and device authentication.

The codebase already uses protocol-based dependency injection on iOS and interface/class-based injection on Android, making it straightforward to create mock implementations for isolated unit testing.

Test Infrastructure

iOS — XCTest via SPM

Tests are built with Swift Package Manager using the package manifest at packages/bcsc-core/Package.swift. The key concepts:

• BcscCoreTestable target: A subset of production iOS source files compiled for the simulator (without React Native / CocoaPods dependencies). Only files listed in the sources: array are included.
• BcscCoreTests test target: XCTest files under ios/BcscCoreTests/, compiled with @testable import BcscCoreTestable.
• SPM_BUILD flag: A Swift compiler define set in Package.swift via swiftSettings: [.define("SPM_BUILD")]. The file ios/SPMCompat.swift uses #if SPM_BUILD to provide lightweight stubs (e.g., SecureRandom, Data.arrayOfBytes()) for types from JWE files that aren't included in the SPM target.
• Scheme name: xcodebuild uses BcscCoreTests-Package (SPM auto-appends -Package).

Adding a new iOS source file to the test target

If the code under test references types in a file not yet in Package.swift, add it to the sources: array in the BcscCoreTestable target. If that file depends on types from excluded files (e.g., JWE/crypto), add stubs to SPMCompat.swift behind #if SPM_BUILD.

Adding a new iOS test file

1. Create a new .swift file in ios/BcscCoreTests/.
2. Import frameworks and the testable module:

   import LocalAuthentication  // if testing LAPolicy/biometric types
   import XCTest
   @testable import BcscCoreTestable
   

3. Write XCTestCase subclasses. Follow the naming convention {ClassUnderTest}Tests.
4. Run with yarn test:ios or directly:

   xcodebuild test -scheme BcscCoreTests-Package \
     -destination 'platform=iOS Simulator,name=iPhone 16,OS=latest' \
     -skipPackagePluginValidation