/**
* Test Fixtures: Decorator Patterns
*
* Various TypeScript decorator patterns used to test PatternMatcher.
* These examples represent NestJS-style and similar decorator-based frameworks.
*
* Pattern Type: 'decorator' - Decorators like @Get(), @Post(), @Body()
*/
// ============================================================================
// Mock Decorators (for type checking)
// ============================================================================
// Route decorators
function Controller(path?: string): ClassDecorator {
return (target) => target;
}
function Get(path?: string): MethodDecorator {
return (target, key, descriptor) => descriptor;
}
function Post(path?: string): MethodDecorator {
return (target, key, descriptor) => descriptor;
}
function Put(path?: string): MethodDecorator {
return (target, key, descriptor) => descriptor;
}
function Delete(path?: string): MethodDecorator {
return (target, key, descriptor) => descriptor;
}
function Patch(path?: string): MethodDecorator {
return (target, key, descriptor) => descriptor;
}
// Parameter decorators
function Body(key?: string): ParameterDecorator {
return (target, propertyKey, parameterIndex) => {};
}
function Query(key?: string): ParameterDecorator {
return (target, propertyKey, parameterIndex) => {};
}
function Param(key?: string): ParameterDecorator {
return (target, propertyKey, parameterIndex) => {};
}
function Headers(key?: string): ParameterDecorator {
return (target, propertyKey, parameterIndex) => {};
}
// Schema/Validation decorators
function ApiProperty(options?: any): PropertyDecorator {
return (target, propertyKey) => {};
}
function IsString(): PropertyDecorator {
return (target, propertyKey) => {};
}
function IsNumber(): PropertyDecorator {
return (target, propertyKey) => {};
}
function IsOptional(): PropertyDecorator {
return (target, propertyKey) => {};
}
function IsEmail(): PropertyDecorator {
return (target, propertyKey) => {};
}
function MinLength(min: number): PropertyDecorator {
return (target, propertyKey) => {};
}
function MaxLength(max: number): PropertyDecorator {
return (target, propertyKey) => {};
}
// Response/API decorators
function ApiResponse(options: { status: number; type?: any; description?: string }): MethodDecorator {
return (target, key, descriptor) => descriptor;
}
function ApiBody(options: { type: any; required?: boolean }): MethodDecorator {
return (target, key, descriptor) => descriptor;
}
function ApiOperation(options: { summary: string; description?: string }): MethodDecorator {
return (target, key, descriptor) => descriptor;
}
// Injectable decorator
function Injectable(): ClassDecorator {
return (target) => target;
}
// ============================================================================
// DTO Classes with Validation Decorators
// ============================================================================
/**
* CreateUserDto - DTO with validation decorators
* Expected: Extract schema from decorated properties
*/
class CreateUserDto {
@ApiProperty({ description: 'User name' })
@IsString()
@MinLength(1)
@MaxLength(100)
name!: string;
@ApiProperty({ description: 'User email', format: 'email' })
@IsEmail()
email!: string;
@ApiProperty({ description: 'User age', required: false })
@IsNumber()
@IsOptional()
age?: number;
@ApiProperty({ description: 'User password' })
@IsString()
@MinLength(8)
password!: string;
}
/**
* UpdateUserDto - Partial DTO for updates
*/
class UpdateUserDto {
@IsString()
@IsOptional()
name?: string;
@IsEmail()
@IsOptional()
email?: string;
@IsNumber()
@IsOptional()
age?: number;
}
/**
* UserResponseDto - Response DTO
*/
class UserResponseDto {
@ApiProperty({ description: 'User ID' })
id!: string;
@ApiProperty({ description: 'User name' })
name!: string;
@ApiProperty({ description: 'User email' })
email!: string;
@ApiProperty({ description: 'Creation timestamp' })
createdAt!: Date;
}
// ============================================================================
// NestJS Controller Example
// ============================================================================
/**
* UsersController - Full NestJS-style controller
* Expected: Match @Controller, @Get, @Post, @Put, @Delete decorators
*/
@Controller('users')
class UsersController {
/**
* Get all users
*/
@Get()
@ApiOperation({ summary: 'List all users' })
@ApiResponse({ status: 200, type: [UserResponseDto] })
findAll(@Query('limit') limit?: number): UserResponseDto[] {
return [];
}
/**
* Get user by ID
*/
@Get(':id')
@ApiOperation({ summary: 'Get user by ID' })
@ApiResponse({ status: 200, type: UserResponseDto })
@ApiResponse({ status: 404, description: 'User not found' })
findOne(@Param('id') id: string): UserResponseDto {
return { id, name: '', email: '', createdAt: new Date() };
}
/**
* Create new user
*/
@Post()
@ApiOperation({ summary: 'Create new user' })
@ApiBody({ type: CreateUserDto, required: true })
@ApiResponse({ status: 201, type: UserResponseDto })
create(@Body() createUserDto: CreateUserDto): UserResponseDto {
return { id: '1', name: createUserDto.name, email: createUserDto.email, createdAt: new Date() };
}
/**
* Update user
*/
@Put(':id')
@ApiOperation({ summary: 'Update user' })
@ApiBody({ type: UpdateUserDto })
@ApiResponse({ status: 200, type: UserResponseDto })
update(
@Param('id') id: string,
@Body() updateUserDto: UpdateUserDto
): UserResponseDto {
return { id, name: '', email: '', createdAt: new Date() };
}
/**
* Partially update user
*/
@Patch(':id')
@ApiOperation({ summary: 'Partially update user' })
@ApiBody({ type: UpdateUserDto })
@ApiResponse({ status: 200, type: UserResponseDto })
partialUpdate(
@Param('id') id: string,
@Body() updateUserDto: UpdateUserDto
): UserResponseDto {
return { id, name: '', email: '', createdAt: new Date() };
}
/**
* Delete user
*/
@Delete(':id')
@ApiOperation({ summary: 'Delete user' })
@ApiResponse({ status: 204, description: 'User deleted' })
remove(@Param('id') id: string): void {
// Delete logic
}
}
// ============================================================================
// Posts Controller with Nested Routes
// ============================================================================
@Controller('posts')
class PostsController {
@Get()
@ApiResponse({ status: 200 })
findAll(): any[] {
return [];
}
@Post()
@ApiBody({ type: Object })
create(@Body() body: any): any {
return body;
}
@Get(':postId/comments')
findComments(@Param('postId') postId: string): any[] {
return [];
}
@Post(':postId/comments')
createComment(
@Param('postId') postId: string,
@Body() body: any
): any {
return body;
}
}
// ============================================================================
// Service with Injectable Decorator
// ============================================================================
@Injectable()
class UsersService {
findAll(): UserResponseDto[] {
return [];
}
findOne(id: string): UserResponseDto | null {
return null;
}
create(dto: CreateUserDto): UserResponseDto {
return { id: '1', name: dto.name, email: dto.email, createdAt: new Date() };
}
}
// ============================================================================
// Edge Cases
// ============================================================================
// Multiple decorators on same element
class MultiDecoratorDto {
@IsString()
@MinLength(1)
@MaxLength(50)
@ApiProperty({ description: 'Multi-decorated field' })
multiField!: string;
}
// Decorator without parentheses (property decorator shorthand)
// Note: This is valid TypeScript but less common
function SimpleDecorator(target: any, propertyKey: string) {}
class SimpleDecoratorExample {
@SimpleDecorator
simpleField!: string;
}
// Class decorator with options
function Module(options: { imports?: any[]; controllers?: any[]; providers?: any[] }): ClassDecorator {
return (target) => target;
}
@Module({
imports: [],
controllers: [UsersController, PostsController],
providers: [UsersService],
})
class AppModule {}
export {
CreateUserDto,
UpdateUserDto,
UserResponseDto,
UsersController,
PostsController,
UsersService,
MultiDecoratorDto,
SimpleDecoratorExample,
AppModule,
};
