FOSMVVM ViewModel Test Generator

Generate test files for ViewModels following FOSMVVM testing patterns.

Conceptual Foundation

For full architecture context, see FOSMVVMArchitecture.md | OpenClaw reference

ViewModel testing in FOSMVVM verifies three critical aspects:

1. Codable round-trip - ViewModel encodes and decodes without data loss
Versioning stability - Structure hasn't changed unexpectedly
Multi-locale translations - All @LocalizedString properties have values in all supported locales

The LocalizableTestCase protocol provides infrastructure that tests all three in a single call.

When to Use This Skill

- Creating tests for new ViewModels
Adding test coverage to existing ViewModels
Verifying localization completeness across locales
Testing ViewModels with embedded/nested child ViewModels
Verifying @LocalizedSubs substitution behavior

What This Skill Generates

File	Location	Purpose
INLINECODE3	INLINECODE4	Test suite conforming to INLINECODE5
INLINECODE6

Tests/{Target}Tests/TestYAML/ | YAML translations for test (if needed) |

The Testing Pattern

Standard Pattern (Most Tests)

For most ViewModels, a single line provides complete coverage:

CODEBLOCK0

This verifies:

- Codable encoding/decoding
Versioned ViewModel stability
Translations exist for all locales (en, es by default)

This is sufficient for the vast majority of ViewModel tests.

Extended Pattern (Specific Formatting Verification)

When testing specific formatting behavior (substitutions, compound strings), add locale-specific assertions:

CODEBLOCK1

This is optional - use only when verifying specific formatting techniques.

LocalizableTestCase Protocol

Test suites conform to LocalizableTestCase to access testing infrastructure:

CODEBLOCK2

The {ViewModelsTarget}.resourceAccess is the resource accessor defined when creating the ViewModels SPM target (via FOSResourceAccessor build tool plugin).

What LocalizableTestCase Provides

Property/Method	Purpose
INLINECODE11	Required - the localization store
INLINECODE12

Testing Methods

Method	Use When
INLINECODE18	Primary - complete ViewModel testing
INLINECODE19

YAML Requirements

ViewModels with @LocalizedString

Every ViewModel with @LocalizedString properties needs YAML entries:

CODEBLOCK3

CODEBLOCK4

Embedded ViewModels

When a ViewModel contains child ViewModels, all types in the hierarchy need YAML entries:

CODEBLOCK5

Both BoardViewModel and CardViewModel need YAML entries (can be in same or separate files).

Private Test ViewModels

When tests define private ViewModel structs for testing specific scenarios, those also need YAML:

CODEBLOCK6

Add entries to a test YAML file for these private types.

How to Use This Skill

Invocation:
/fosmvvm-viewmodel-test-generator

Prerequisites:

- ViewModel structure understood from conversation context
Localization properties identified (@LocalizedString, @LocalizedSubs, etc.)
YAML localization files exist or will be created
Child ViewModels identified (if any)

Workflow integration:
This skill is used when adding test coverage for ViewModels. The skill references conversation context automatically—no file paths or Q&A needed. Typically follows fosmvvm-viewmodel-generator.

Pattern Implementation

This skill references conversation context to determine test structure:

ViewModel Analysis

From conversation context, the skill identifies:

- ViewModels to test (from prior discussion or codebase)
Localization requirements (@LocalizedString properties)
Child ViewModels (embedded within parent)
Substitution behavior (@LocalizedSubs needing specific verification)

YAML Coverage Check

Verifies completeness:

- ViewModel YAML entries (all @LocalizedString properties)
Child ViewModel entries (nested types)
Locale coverage (en, es, or project-specific locales)

Test File Generation

Creates test suite with:

- LocalizableTestCase conformance
Localization store initialization
expectFullViewModelTests() calls for each ViewModel
Optional specific formatting tests (substitutions, compound strings)

Context Sources

Skill references information from:

- Prior conversation: ViewModels discussed or recently created
ViewModel code: If Claude has read ViewModel files into context
YAML files: From codebase analysis of existing localizations
Test patterns: From existing test files in project

File Templates

See reference.md for complete file templates.

Common Scenarios

Testing a Single Top-Level ViewModel

CODEBLOCK7

Testing Multiple Related ViewModels

CODEBLOCK8

Testing with Custom Locales

CODEBLOCK9

Testing Substitution Behavior

CODEBLOCK10

Testing Embedded ViewModels

CODEBLOCK11

Troubleshooting

"Missing Translation" Error

CODEBLOCK12

Cause: YAML entry missing for a @LocalizedString property.

Fix: Add the property to the YAML file:
CODEBLOCK13

"Is pending localization" Error

Cause: The ViewModel wasn't encoded with a localizing encoder.

Fix: Ensure using encoder(locale:) or expectFullViewModelTests().

Test Passes But Translations Seem Wrong

Cause: YAML values exist but may have typos or wrong content.

Fix: Add specific assertions to verify exact values:

let vm = try .stub().toJSON(encoder: encoder(locale: en)).fromJSON()
#expect(try vm.title.localizedString == "Expected Value")

Naming Conventions

Concept	Convention	Example
Test suite	INLINECODE30	INLINECODE31
Test file

{Feature}ViewModelTests.swift | DashboardViewModelTests.swift |
| YAML file | {ViewModelName}.yml | DashboardViewModel.yml |
| Test method | {viewModelName}() or descriptive | dashboardViewModel() |

Version History

Version	Date	Changes
1.0	2025-01-02	Initial skill
1.1

2026-01-19 | Updated LocalizableTestCase example to use {ViewModelsTarget}.resourceAccess pattern. | | 1.2 | 2026-01-24 | Update to context-aware approach (remove file-parsing/Q&A). Skill references conversation context instead of asking questions or accepting file paths. |

FOSMVVM ViewModel 测试生成器

按照 FOSMVVM 测试模式为 ViewModel 生成测试文件。

概念基础

完整架构上下文，请参阅 FOSMVVMArchitecture.md | OpenClaw 参考

FOSMVVM 中的 ViewModel 测试验证三个关键方面：

1. Codable 往返 - ViewModel 编码和解码无数据丢失
版本稳定性 - 结构未发生意外变化
多语言翻译 - 所有 @LocalizedString 属性在所有支持的语言环境中都有值

LocalizableTestCase 协议提供了一次调用测试所有三者的基础设施。

何时使用此技能

- 为新的 ViewModel 创建测试
为现有的 ViewModel 添加测试覆盖
验证跨语言环境的本地化完整性
测试包含嵌入/嵌套子 ViewModel 的 ViewModel
验证 @LocalizedSubs 替换行为

此技能生成的内容

文件	位置	用途
{Name}ViewModelTests.swift	Tests/{Target}Tests/Localization/	符合 LocalizableTestCase 的测试套件
{Name}ViewModel.yml

Tests/{Target}Tests/TestYAML/ | 测试用的 YAML 翻译（如果需要） |

测试模式

标准模式（大多数测试）

对于大多数 ViewModel，一行代码即可提供完整覆盖：

swift
@Test func dashboardViewModel() throws {
try expectFullViewModelTests(DashboardViewModel.self)
}

此操作验证：

- Codable 编码/解码
版本化的 ViewModel 稳定性
所有语言环境（默认 en, es）的翻译存在

这对于绝大多数 ViewModel 测试来说已经足够。

扩展模式（特定格式化验证）

当测试特定的格式化行为（替换、复合字符串）时，添加特定于语言环境的断言：

swift
@Test func greetingWithSubstitution() throws {
try expectFullViewModelTests(GreetingViewModel.self)

// 验证特定的替换行为
let vm: GreetingViewModel = try .stub()
.toJSON(encoder: encoder(locale: en))
.fromJSON()

#expect(try vm.welcomeMessage.localizedString == Welcome, John!)
}

这是可选的 - 仅在验证特定格式化技术时使用。

LocalizableTestCase 协议

测试套件符合 LocalizableTestCase 以访问测试基础设施：

swift
import FOSFoundation
@testable import FOSMVVM
import FOSTesting
import Foundation
import Testing
@testable import {ViewModelsTarget}

@Suite(我的 ViewModel 测试)
struct MyViewModelTests: LocalizableTestCase {
let locStore: LocalizationStore

init() throws {
self.locStore = try Self.loadLocalizationStore(
bundle: {ViewModelsTarget}.resourceAccess,
resourceDirectoryName:
)
}
}

{ViewModelsTarget}.resourceAccess 是在创建 ViewModels SPM 目标时（通过 FOSResourceAccessor 构建工具插件）定义的资源访问器。

LocalizableTestCase 提供的内容

属性/方法	用途
locStore	必需 - 本地化存储
locales

测试方法

方法	使用时机
expectFullViewModelTests(:)	主要 - 完整的 ViewModel 测试
expectTranslations(:)

YAML 要求

包含 @LocalizedString 的 ViewModel

每个具有 @LocalizedString 属性的 ViewModel 都需要 YAML 条目：

swift
@ViewModel
public struct DashboardViewModel: RequestableViewModel {
@LocalizedString public var pageTitle // 需要 YAML 条目
@LocalizedString public var emptyMessage // 需要 YAML 条目
public let itemCount: Int // 不需要 YAML
}

yaml

DashboardViewModel.yml

en:
DashboardViewModel:
pageTitle: Dashboard
emptyMessage: No items yet

es:
DashboardViewModel:
pageTitle: Tablero
emptyMessage: No hay elementos todavía

嵌入的 ViewModel

当 ViewModel 包含子 ViewModel 时，层次结构中的所有类型都需要 YAML 条目：

swift
@ViewModel
public struct BoardViewModel: RequestableViewModel {
@LocalizedString public var title
public let cards: [CardViewModel] // 子 ViewModel
}

@ViewModel
public struct CardViewModel {
@LocalizedString public var cardTitle
}

BoardViewModel 和 CardViewModel 都需要 YAML 条目（可以在同一个或不同的文件中）。

私有测试 ViewModel

当测试为测试特定场景定义私有 ViewModel 结构体时，这些也需要 YAML：

swift
// 在测试文件中
private struct TestParentViewModel: ViewModel {
@LocalizedString var title
let children: [TestChildViewModel]
}

private struct TestChildViewModel: ViewModel {
@LocalizedString var label
}

为这些私有类型在测试 YAML 文件中添加条目。

如何使用此技能

调用：
/fosmvvm-viewmodel-test-generator

前提条件：

- 从对话上下文中理解 ViewModel 结构
已识别本地化属性（@LocalizedString, @LocalizedSubs 等）
YAML 本地化文件已存在或将被创建
已识别子 ViewModel（如果有）

工作流集成：
此技能在添加 ViewModel 测试覆盖时使用。该技能自动引用对话上下文——无需文件路径或问答。通常跟在 fosmvvm-viewmodel-generator 之后。

模式实现

此技能引用对话上下文来确定测试结构：

ViewModel 分析

从对话上下文中，该技能识别：

- 要测试的 ViewModel（来自之前的讨论或代码库）
本地化要求（@LocalizedString 属性）
子 ViewModel（嵌入在父级中）
替换行为（需要特定验证的 @LocalizedSubs）

YAML 覆盖检查

验证完整性：

- ViewModel YAML 条目（所有 @LocalizedString 属性）
子 ViewModel 条目（嵌套类型）
语言环境覆盖（en, es 或项目特定的语言环境）

测试文件生成

创建包含以下内容的测试套件：

- LocalizableTestCase 符合性
本地化存储初始化
每个 ViewModel 的 expectFullViewModelTests() 调用
可选的特定格式化测试（替换、复合字符串）

上下文来源

技能引用以下信息：

- 之前的对话：讨论过或最近创建的 ViewModel
ViewModel 代码：如果 Claude 已将 ViewModel 文件读入上下文
YAML 文件：来自对现有本地化的代码库分析
测试模式：来自项目中现有的测试文件

文件模板

请参阅 reference.md 获取完整的文件模板。

常见场景

测试单个顶层 ViewModel

swift
@Test func dashboardViewModel() throws {
try expectFullViewModelTests(DashboardViewModel.self)
}

测试多个相关的 ViewModel

swift
@Test func boardViewModels() throws {
try expectFullViewModelTests(BoardViewModel.self)
try expectFullViewModelTests(ColumnViewModel.self)
try expectFullViewModelTests(CardViewModel.self)
}

使用自定义语言环境进行测试

swift
var locales: Set { [en, es, enGB] } // 覆盖默认值

@Test func multiLocaleViewModel() throws {
try expectFullViewModelTests(MyViewModel.self)
// 测试 en, es 和 en-GB
}

测试替换行为

swift
@Test func greetingSubstitutions() throws {
try expectFullViewModelTests(GreetingViewModel.self)

let vm: GreetingViewModel = try .stub(userName: Alice)
.toJSON(encoder: encoder(locale: en))
.fromJSON()

#expect(try vm.welcomeMessage.localizedString == Welcome, Alice!)
}

fosmvvm-viewmodel-test-generatorViewModel测试生成器