docs: salvage HarmonyOS ArkTS guidance

2026-05-15 17:02:12 +08:00 · 2026-05-11 21:16:05 -04:00
parent 10d160b95e
commit a8836d7bbd
18 changed files with 1097 additions and 17 deletions
--- a/rules/README.md
+++ b/rules/README.md
@@ -20,7 +20,8 @@ rules/
 ├── golang/          # Go specific
 ├── web/             # Web and frontend specific
 ├── swift/           # Swift specific
-└── php/             # PHP specific
+├── php/             # PHP specific
+└── arkts/           # HarmonyOS / ArkTS specific
 ```

 - **common/** contains universal principles — no language-specific code examples.
@@ -39,6 +40,7 @@ rules/
 ./install.sh web
 ./install.sh swift
 ./install.sh php
+./install.sh arkts

 # Install multiple languages at once
 ./install.sh typescript python
@@ -64,6 +66,7 @@ cp -r rules/golang ~/.claude/rules/golang
 cp -r rules/web ~/.claude/rules/web
 cp -r rules/swift ~/.claude/rules/swift
 cp -r rules/php ~/.claude/rules/php
+cp -r rules/arkts ~/.claude/rules/arkts

 # Attention ! ! ! Configure according to your actual project requirements; the configuration here is for reference only.
 ```
--- a/rules/arkts/coding-style.md
+++ b/rules/arkts/coding-style.md
@@ -0,0 +1,153 @@
+---
+paths:
+  - "**/*.ets"
+  - "**/*.ts"
+  - "**/module.json5"
+  - "**/oh-package.json5"
+  - "**/build-profile.json5"
+---
+# HarmonyOS / ArkTS Coding Style
+
+> This file extends [common/coding-style.md](../common/coding-style.md) with HarmonyOS and ArkTS-specific content.
+
+## ArkTS Language Constraints
+
+ArkTS is a strict, statically-typed subset of TypeScript. Violating these constraints causes **compilation failures**.
+
+### Type System
+
+- No `any` or `unknown` types - always use explicit types
+- No index access types - use type names directly
+- No conditional type aliases or `infer` keyword
+- No intersection types - use inheritance
+- No mapped types - use classes and regular idioms
+- No `typeof` for type annotations - use explicit type declarations
+- No `as const` assertions - use explicit type annotations
+- No structural typing - use inheritance, interfaces, or type aliases
+- No TypeScript utility types except `Partial`, `Required`, `Readonly`, `Record`
+- For `Record<K, V>`, index expression type is `V | undefined`
+- Omit type annotations in `catch` clauses (ArkTS does not support `any`/`unknown`)
+
+### Functions & Classes
+
+- No function expressions - use arrow functions
+- No nested functions - use lambdas
+- No generator functions - use `async`/`await` for multitasking
+- No `Function.apply`, `Function.call`, `Function.bind` - follow traditional OOP for `this`
+- No constructor type expressions - use lambdas
+- No constructor signatures in interfaces or object types - use methods or classes
+- No declaring class fields in constructors - declare in class body
+- No `this` in standalone functions or static methods - only in instance methods
+- No `new.target`
+- No definite assignment assertions (`let v!: T`) - use initialized declarations
+- No class literals - introduce named class types
+- No using classes as objects (assigning to variables) - class declarations introduce types, not values
+- Only one static block per class - merge all static statements
+
+### Object & Property Access
+
+- No dynamic field declaration or `obj["field"]` access - use `obj.field` syntax
+- No `delete` operator - use nullable type with `null` to mark absence
+- No prototype assignment - use classes and interfaces
+- No `in` operator - use `instanceof`
+- No reassigning object methods - use wrapper functions or inheritance
+- No `Symbol()` API (except `Symbol.iterator`)
+- No `globalThis` or global scope - use explicit module exports/imports
+- No namespaces as objects - use classes or modules
+- No statements inside namespaces - use functions
+
+### Destructuring & Spread
+
+- No destructuring assignments or variable declarations - use intermediate objects and field-by-field access
+- No destructuring parameter declarations - pass parameters directly, assign local names manually
+- Spread operator only for expanding arrays (or array-derived classes) into rest parameters or array literals
+
+### Modules & Imports
+
+- No `require()` - use regular `import` syntax
+- No `export = ...` - use normal export/import
+- No import assertions - imports are compile-time in ArkTS
+- No UMD modules
+- No wildcards in module names
+- All `import` statements must appear before all other statements
+- TypeScript codebases must not depend on ArkTS codebases via import (reverse is supported)
+
+### Other Restrictions
+
+- No `var` - use `let`
+- No `for...in` loops - use regular `for` loops for arrays
+- No `with` statements
+- No JSX expressions
+- No `#` private identifiers - use `private` keyword
+- No declaration merging (classes, interfaces, enums) - keep definitions compact
+- No index signatures - use arrays
+- Comma operator only in `for` loops
+- Unary operators `+`, `-`, `~` only for numeric types (no implicit string conversion)
+- Enum members: only same-type compile-time expressions for explicit initializers
+- Function return type inference is limited - specify return types explicitly when calling functions with omitted return types
+
+### Object Literals
+
+- Supported only when compiler can infer the corresponding class or interface
+- NOT supported for: `any`/`Object`/`object` types, classes/interfaces with methods, classes with parameterized constructors, classes with `readonly` fields
+
+## Naming Conventions
+
+- Variables / functions: `camelCase` (e.g., `getUserInfo`, `goodsList`)
+- Classes / interfaces: `PascalCase` (e.g., `UserViewModel`, `IGoodsModel`)
+- Constants: `UPPER_SNAKE_CASE` (e.g., `MAX_PAGE_SIZE`, `COLOR_PRIMARY`)
+- File names: `PascalCase` for components (e.g., `HomePage.ets`), `camelCase` for utilities
+
+## Formatting
+
+- Prefer double quotes for strings
+- Semicolons at end of statements
+- Never use `var` - prefer `const`, then `let`
+- All methods, parameters, return values must have complete type annotations
+
+## File Organization
+
+- Component files (`.ets`): one `@ComponentV2` per file
+- ViewModel files: one ViewModel class per file
+- Model files: related data models may share a file
+- Keep files under 400 lines; extract helpers for files approaching 800 lines
+
+## Comments
+
+- File header: `@file` (file purpose) + `@author` (developer), if the project already uses file headers
+- Public methods: JSDoc with `@param`, `@returns`; add `@example` for complex methods
+- Match the project's existing documentation language; use English unless the repository has already standardized on Chinese comments
+
+## Error Handling
+
+```typescript
+// Use try/catch with proper error handling
+try {
+  const result = await riskyOperation()
+  return result
+} catch (error) {
+  hilog.error(0x0000, 'TAG', 'Operation failed: %{public}s', error)
+  throw new Error('User-friendly error message')
+}
+```
+
+## Immutability
+
+Follow the common immutability principles - create new objects instead of mutating:
+
+```typescript
+// BAD: mutation
+function updateUser(user: UserModel, name: string): UserModel {
+  user.name = name  // direct mutation
+  return user
+}
+
+// GOOD: immutable - create new instance
+function updateUser(user: UserModel, name: string): UserModel {
+  const updated = new UserModel()
+  updated.id = user.id
+  updated.name = name
+  updated.email = user.email
+  return updated
+}
+```
--- a/rules/arkts/hooks.md
+++ b/rules/arkts/hooks.md
@@ -0,0 +1,135 @@
+---
+paths:
+  - "**/*.ets"
+  - "**/*.ts"
+  - "**/module.json5"
+  - "**/oh-package.json5"
+---
+# HarmonyOS / ArkTS Hooks
+
+> This file extends [common/hooks.md](../common/hooks.md) with HarmonyOS-specific build and validation hooks.
+
+## Build Commands
+
+### HAP Package Build
+
+```bash
+# Build HAP package (global hvigor environment)
+hvigorw assembleHap -p product=default
+
+# Build with specific module
+hvigorw assembleHap -p module=entry -p product=default
+
+# Clean build
+hvigorw clean
+```
+
+### DevEco Studio CLI
+
+```bash
+# Check project structure
+hvigorw --version
+
+# Install dependencies
+ohpm install
+
+# Update dependencies
+ohpm update
+```
+
+## Recommended PostToolUse Hooks
+
+### After Editing .ets/.ts Files
+
+Run hvigor build to check for ArkTS compilation errors:
+
+```json
+{
+  "type": "PostToolUse",
+  "matcher": {
+    "tool": ["Edit", "Write"],
+    "filePath": ["**/*.ets", "**/*.ts"]
+  },
+  "hooks": [
+    {
+      "command": "hvigorw assembleHap -p product=default 2>&1 | tail -20",
+      "async": true,
+      "timeout": 60000
+    }
+  ]
+}
+```
+
+### After Editing module.json5
+
+Validate permission and ability declarations:
+
+```json
+{
+  "type": "PostToolUse",
+  "matcher": {
+    "tool": "Edit",
+    "filePath": "**/module.json5"
+  },
+  "hooks": [
+    {
+      "command": "echo '[HarmonyOS] module.json5 modified - verify permissions and abilities'",
+      "async": false
+    }
+  ]
+}
+```
+
+### After Editing oh-package.json5
+
+Reinstall dependencies:
+
+```json
+{
+  "type": "PostToolUse",
+  "matcher": {
+    "tool": "Edit",
+    "filePath": "**/oh-package.json5"
+  },
+  "hooks": [
+    {
+      "command": "ohpm install 2>&1 | tail -10",
+      "async": true,
+      "timeout": 30000
+    }
+  ]
+}
+```
+
+## PreToolUse Hooks
+
+### V1 Decorator Guard
+
+Warn when code contains V1 state management decorators:
+
+```json
+{
+  "type": "PreToolUse",
+  "matcher": {
+    "tool": ["Write", "Edit"],
+    "filePath": "**/*.ets"
+  },
+  "hooks": [
+    {
+      "command": "echo '[HarmonyOS] Reminder: Use @ComponentV2 / @Local / @Param - V1 decorators (@State, @Prop, @Link) are prohibited'"
+    }
+  ]
+}
+```
+
+## Validation Checklist
+
+After each implementation cycle, verify:
+
+- [ ] `hvigorw assembleHap` completes without errors
+- [ ] No V1 decorators in new or modified `.ets` files
+- [ ] No `@ohos.router` imports in new or modified files
+- [ ] All API permissions declared in `module.json5`
+- [ ] All dependencies listed in `oh-package.json5`
+- [ ] Resource strings added to all i18n directories
+- [ ] Dark theme colors provided for new color resources
--- a/rules/arkts/patterns.md
+++ b/rules/arkts/patterns.md
@@ -0,0 +1,236 @@
+---
+paths:
+  - "**/*.ets"
+  - "**/*.ts"
+---
+# HarmonyOS / ArkTS Patterns
+
+> This file extends [common/patterns.md](../common/patterns.md) with HarmonyOS and ArkTS-specific patterns.
+
+## State Management: V2 Only
+
+**MUST use** ArkUI State Management V2. V1 decorators are deprecated and must not be used.
+
+### V2 Decorators
+
+| Decorator | Purpose |
+|-----------|---------|
+| `@ComponentV2` | Marks a struct as a V2 component |
+| `@Local` | Local state within a component |
+| `@Param` | Props received from parent (read-only) |
+| `@Event` | Callback events from child to parent |
+| `@Provider` | Provides state to descendant components |
+| `@Consumer` | Consumes state from ancestor `@Provider` |
+| `@Monitor` | Watches for state changes (replaces V1 `@Watch`) |
+| `@Computed` | Derived/computed values |
+| `@ObservedV2` | Makes a class observable for V2 state management |
+| `@Trace` | Marks observable properties in `@ObservedV2` classes |
+
+### Prohibited V1 Decorators
+
+Never use: `@State`, `@Prop`, `@Link`, `@ObjectLink`, `@Observed`, `@Provide`, `@Consume`, `@Watch`, `@Component` (use `@ComponentV2` instead).
+
+### V2 Component Example
+
+```typescript
+@ObservedV2
+class UserModel {
+  @Trace name: string = ''
+  @Trace age: number = 0
+}
+
+@ComponentV2
+struct UserCard {
+  @Param user: UserModel = new UserModel()
+  @Event onDelete: () => void = () => {}
+
+  build() {
+    Column() {
+      Text(this.user.name)
+        .fontSize($r('app.float.font_size_title'))
+      Text(`${this.user.age}`)
+        .fontSize($r('app.float.font_size_body'))
+      Button($r('app.string.delete'))
+        .onClick(() => this.onDelete())
+    }
+  }
+}
+```
+
+### State Synchronization
+
+```typescript
+@ComponentV2
+struct ParentPage {
+  @Provider('userState') userModel: UserModel = new UserModel()
+
+  build() {
+    Column() {
+      ChildComponent()  // automatically receives @Consumer('userState')
+    }
+  }
+}
+
+@ComponentV2
+struct ChildComponent {
+  @Consumer('userState') userModel: UserModel = new UserModel()
+
+  build() {
+    Text(this.userModel.name)
+  }
+}
+```
+
+## Routing: Navigation Only
+
+**MUST use** `Navigation` component with `NavPathStack`. Never use `@ohos.router`.
+
+### Navigation Setup
+
+```typescript
+@ComponentV2
+struct MainPage {
+  @Local navPathStack: NavPathStack = new NavPathStack()
+
+  build() {
+    Navigation(this.navPathStack) {
+      // Home content
+    }
+    .navDestination(this.routerMap)
+  }
+
+  @Builder
+  routerMap(name: string, param: ESObject) {
+    if (name === 'detail') {
+      DetailPage()
+    } else if (name === 'settings') {
+      SettingsPage()
+    }
+  }
+}
+```
+
+### Page Navigation
+
+```typescript
+// Push a new page
+this.navPathStack.pushPath({ name: 'detail', param: { id: '123' } })
+
+// Replace current page
+this.navPathStack.replacePath({ name: 'settings' })
+
+// Pop back
+this.navPathStack.pop()
+
+// Pop to root
+this.navPathStack.clear()
+```
+
+### NavDestination Sub-page
+
+```typescript
+@ComponentV2
+struct DetailPage {
+  build() {
+    NavDestination() {
+      Column() {
+        Text($r('app.string.detail_title'))
+      }
+    }
+    .title($r('app.string.detail_nav_title'))
+  }
+}
+```
+
+## Architecture Pattern: MVVM
+
+Recommended architecture for HarmonyOS applications:
+
+```
+feature/
+  |-- model/           # Data models (@ObservedV2 classes)
+  |-- viewmodel/       # Business logic (ViewModel classes)
+  |-- view/            # UI components (@ComponentV2 structs)
+  |-- service/         # API calls, data access
+```
+
+- **View**: Only rendering logic, no business logic in `build()`
+- **ViewModel**: All business logic encapsulated here
+- **Model**: Pure data classes with `@ObservedV2` and `@Trace`
+- **Service**: Network requests, database operations, file I/O
+
+## ArkUI Animation Patterns
+
+### State-Driven Animation
+
+```typescript
+@ComponentV2
+struct AnimatedCard {
+  @Local isExpanded: boolean = false
+  @Local cardScale: number = 0.8
+
+  build() {
+    Column() {
+      // Content
+    }
+    .scale({ x: this.cardScale, y: this.cardScale })
+    .animation({ duration: 300, curve: Curve.EaseInOut })
+    .onClick(() => {
+      this.isExpanded = !this.isExpanded
+      this.cardScale = this.isExpanded ? 1.0 : 0.8
+    })
+  }
+}
+```
+
+### Animation Rules
+
+- Prefer native HarmonyOS animation APIs and advanced templates
+- Use declarative UI with state-driven animations (change state variables to trigger animations)
+- Set `renderGroup(true)` for complex sub-component animations to reduce render batches
+- **NEVER** frequently change `width`, `height`, `padding`, `margin` during animations - severe performance impact
+- Use `animateTo` for explicit animation control
+- Prefer `transform` (translate, scale, rotate) and `opacity` for performant animations
+
+## Performance Patterns
+
+### LazyForEach for Large Lists
+
+```typescript
+@ComponentV2
+struct LargeList {
+  @Local dataSource: MyDataSource = new MyDataSource()
+
+  build() {
+    List() {
+      LazyForEach(this.dataSource, (item: ItemModel) => {
+        ListItem() {
+          ItemComponent({ item: item })
+        }
+      }, (item: ItemModel) => item.id)
+    }
+  }
+}
+```
+
+### Component Reuse
+
+- Extract reusable components into separate files
+- Use `@Builder` for lightweight UI fragments within a component
+- Use `@Param` for configurable components
+
+## Resource References
+
+Always define UI constants as resources and reference via `$r()`:
+
+```typescript
+// BAD: hardcoded values
+Text('Hello')
+  .fontSize(16)
+  .fontColor('#333333')
+
+// GOOD: resource references
+Text($r('app.string.greeting'))
+  .fontSize($r('app.float.font_size_body'))
+  .fontColor($r('app.color.text_primary'))
+```
--- a/rules/arkts/security.md
+++ b/rules/arkts/security.md
@@ -0,0 +1,141 @@
+---
+paths:
+  - "**/*.ets"
+  - "**/*.ts"
+  - "**/module.json5"
+---
+# HarmonyOS / ArkTS Security
+
+> This file extends [common/security.md](../common/security.md) with HarmonyOS-specific security practices.
+
+## Permission Management
+
+### Declare Permissions in module.json5
+
+All system API calls requiring permissions must be declared:
+
+```json5
+{
+  "module": {
+    "requestPermissions": [
+      {
+        "name": "ohos.permission.INTERNET",
+        "reason": "$string:internet_permission_reason",
+        "usedScene": {
+          "abilities": ["EntryAbility"],
+          "when": "always"
+        }
+      }
+    ]
+  }
+}
+```
+
+### Permission Checklist
+
+Before calling system APIs, verify:
+
+- [ ] Permission declared in `module.json5`
+- [ ] Permission reason string defined in resources (for user-facing permissions)
+- [ ] Runtime permission request implemented for sensitive permissions (camera, location, etc.)
+- [ ] Permission check before API call with graceful fallback on denial
+
+### Runtime Permission Request
+
+```typescript
+import { abilityAccessCtrl, bundleManager, Permissions } from '@kit.AbilityKit';
+
+async function checkAndRequestPermission(permission: Permissions): Promise<boolean> {
+  const atManager = abilityAccessCtrl.createAtManager();
+  const bundleInfo = await bundleManager.getBundleInfoForSelf(
+    bundleManager.BundleFlag.GET_BUNDLE_INFO_WITH_APPLICATION
+  );
+  const tokenId = bundleInfo.appInfo.accessTokenId;
+  const grantStatus = await atManager.checkAccessToken(tokenId, permission);
+
+  if (grantStatus === abilityAccessCtrl.GrantStatus.PERMISSION_GRANTED) {
+    return true;
+  }
+
+  const result = await atManager.requestPermissionsFromUser(getContext(), [permission]);
+  return result.authResults[0] === abilityAccessCtrl.GrantStatus.PERMISSION_GRANTED;
+}
+```
+
+## Secret Management
+
+- **NEVER** hardcode API keys, tokens, or passwords in `.ets`/`.ts` source files
+- Use HarmonyOS Preferences API for non-sensitive configuration
+- Use HarmonyOS Keystore for sensitive credentials
+- Environment-specific configs should be managed via build profiles
+
+```typescript
+// BAD: hardcoded secret
+const API_KEY: string = 'sk-xxxxxxxxxxxx';
+
+// GOOD: from build profile config (non-sensitive)
+import { BuildProfile } from 'BuildProfile';
+const endpoint = BuildProfile.API_ENDPOINT;
+
+// GOOD: use HUKS to encrypt/decrypt data without exposing key material
+import { huks } from '@kit.UniversalKeystoreKit';
+async function decryptWithKeystore(alias: string, nonce: Uint8Array, aad: Uint8Array, cipherData: Uint8Array): Promise<Uint8Array> {
+  const options: huks.HuksOptions = {
+    properties: [
+      { tag: huks.HuksTag.HUKS_TAG_ALGORITHM, value: huks.HuksKeyAlg.HUKS_ALG_AES },
+      { tag: huks.HuksTag.HUKS_TAG_PURPOSE, value: huks.HuksKeyPurpose.HUKS_KEY_PURPOSE_DECRYPT },
+      { tag: huks.HuksTag.HUKS_TAG_BLOCK_MODE, value: huks.HuksCipherMode.HUKS_MODE_GCM },
+      { tag: huks.HuksTag.HUKS_TAG_PADDING, value: huks.HuksKeyPadding.HUKS_PADDING_NONE },
+      { tag: huks.HuksTag.HUKS_TAG_NONCE, value: nonce },
+      { tag: huks.HuksTag.HUKS_TAG_ASSOCIATED_DATA, value: aad }
+    ],
+    inData: cipherData
+  };
+  const handle = await huks.initSession(alias, options);
+  const result = await huks.finishSession(handle.handle, options);
+  return result.outData;
+}
+```
+
+## Input Validation
+
+- Validate all user input before processing
+- Sanitize data before displaying in UI to prevent injection
+- Validate deep link parameters before navigation
+
+```typescript
+// Validate before navigation
+function handleDeepLink(uri: string): void {
+  const allowedPaths: string[] = ['detail', 'settings', 'profile'];
+  const parsed = new URL(uri);
+  const path = parsed.pathname.replace('/', '');
+
+  if (!allowedPaths.includes(path)) {
+    hilog.warn(0x0000, 'DeepLink', 'Invalid deep link path: %{public}s', path);
+    return;
+  }
+
+  navPathStack.pushPath({ name: path });
+}
+```
+
+## Network Security
+
+- Always use HTTPS for network requests
+- Validate server certificates
+- Implement request timeout and retry policies
+- Never log sensitive data (tokens, user credentials) in network request/response logs
+
+## Data Storage Security
+
+- Use encrypted preferences for sensitive local data
+- Clear sensitive data from memory when no longer needed
+- Implement proper data lifecycle management
+- Consider data classification (public, internal, confidential) when choosing storage mechanisms
+
+## Dependency Security
+
+- Only use dependencies from trusted sources (official ohpm registry)
+- Verify dependency versions in `oh-package.json5`
+- Regularly check for known vulnerabilities in third-party libraries
+- Pin dependency versions to avoid unexpected updates
--- a/rules/arkts/testing.md
+++ b/rules/arkts/testing.md
@@ -0,0 +1,126 @@
+---
+paths:
+  - "**/*.ets"
+  - "**/*.ts"
+  - "**/ohosTest/**"
+---
+# HarmonyOS / ArkTS Testing
+
+> This file extends [common/testing.md](../common/testing.md) with HarmonyOS-specific testing practices.
+
+## Test Framework
+
+HarmonyOS uses the built-in test framework with `@ohos.test` capabilities:
+
+- **Unit tests**: Located in `src/ohosTest/ets/test/`
+- **UI tests**: Use `@ohos.UiTest` for component testing
+- **Instrument tests**: Run on device/emulator
+
+## Test Directory Structure
+
+```
+module/
+  |-- src/
+  |   |-- main/ets/          # Production code
+  |   |-- ohosTest/ets/      # Test code
+  |       |-- test/
+  |       |   |-- Ability.test.ets
+  |       |   |-- List.test.ets
+  |       |-- TestAbility.ets
+  |       |-- TestRunner.ets
+```
+
+## Running Tests
+
+```bash
+# Run all tests for a module
+hvigorw testHap -p product=default
+
+# Run tests on connected device
+hdc shell aa test -b com.example.app -m entry_test -s unittest /ets/TestRunner/OpenHarmonyTestRunner
+```
+
+## Unit Test Example
+
+```typescript
+import { describe, it, expect } from '@ohos/hypium';
+
+export default function UserViewModelTest() {
+  describe('UserViewModel', () => {
+    it('should_initialize_with_empty_state', 0, () => {
+      const vm = new UserViewModel();
+      expect(vm.userName).assertEqual('');
+      expect(vm.isLoading).assertFalse();
+    });
+
+    it('should_update_user_name', 0, () => {
+      const vm = new UserViewModel();
+      vm.updateUserName('Alice');
+      expect(vm.userName).assertEqual('Alice');
+    });
+
+    it('should_handle_empty_input', 0, () => {
+      const vm = new UserViewModel();
+      vm.updateUserName('');
+      expect(vm.userName).assertEqual('');
+      expect(vm.hasError).assertFalse();
+    });
+  });
+}
+```
+
+## UI Test Example
+
+```typescript
+import { describe, it, expect } from '@ohos/hypium';
+import { Driver, ON } from '@ohos.UiTest';
+
+export default function HomePageUITest() {
+  describe('HomePage_UI', () => {
+    it('should_display_title', 0, async () => {
+      const driver = Driver.create();
+      await driver.delayMs(1000);
+
+      const title = await driver.findComponent(ON.text('Home'));
+      expect(title !== null).assertTrue();
+    });
+
+    it('should_navigate_to_detail_on_click', 0, async () => {
+      const driver = Driver.create();
+      const button = await driver.findComponent(ON.id('detailButton'));
+      await button.click();
+      await driver.delayMs(500);
+
+      const detailTitle = await driver.findComponent(ON.text('Detail'));
+      expect(detailTitle !== null).assertTrue();
+    });
+  });
+}
+```
+
+## TDD Workflow for HarmonyOS
+
+Follow the standard TDD cycle adapted for HarmonyOS:
+
+1. **RED**: Write a failing test in `ohosTest/ets/test/`
+2. **GREEN**: Implement minimal code in `main/ets/` to pass
+3. **REFACTOR**: Clean up while keeping tests green
+4. **BUILD**: Run `hvigorw assembleHap` to verify compilation
+5. **VERIFY**: Run tests on device/emulator
+
+## Test Coverage Requirements
+
+- Minimum 80% coverage for all critical application code (ViewModels, services, utilities)
+- **Unit tests**: All utility functions, ViewModel logic, data models
+- **Integration tests**: API calls, database operations, cross-module interactions
+- **E2E / UI tests**: Critical user flows (login, navigation, data submission)
+- Test edge cases: empty data, network errors, permission denials
+
+## Testing Best Practices
+
+- Keep tests independent - no shared mutable state between tests
+- Mock network calls and system APIs in unit tests
+- Use meaningful test names: `should_[expected_behavior]_when_[condition]`
+- Test V2 state management reactivity: verify `@Trace` properties trigger UI updates
+- Test Navigation flows: verify `NavPathStack` push/pop/replace operations
+- Avoid testing framework internals - focus on business logic and user-visible behavior
--- a/rules/common/agents.md
+++ b/rules/common/agents.md
@@ -16,6 +16,7 @@ Located in `~/.claude/agents/`:
 | refactor-cleaner | Dead code cleanup | Code maintenance |
 | doc-updater | Documentation | Updating docs |
 | rust-reviewer | Rust code review | Rust projects |
+| harmonyos-app-resolver | HarmonyOS app development | HarmonyOS/ArkTS projects |

 ## Immediate Agent Usage