Use union types in Typescript

typescript
Use union types with specific interfaces for mutually exclusive properties instead of a single interface with multiple optional properties.
Bad:
```typescript
interface ConfigOptions {
  fileConfig?: {
    path: string
    encoding?: string

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Install this rule for Coderabbit

Copy the configuration below and add it to your repository as .coderabbit.yml in your project root.

reviews:
  path_instructions:
    - path: "*.ts,*.tsx"
      instructions: |
                
        Use union types with specific interfaces for mutually exclusive properties instead of a single interface with multiple optional properties.
        
        Bad:
        
        ```typescript
        interface ConfigOptions {
          fileConfig?: {
            path: string
            encoding?: string
          }
          dbConfig?: {
            connectionString: string
            poolSize?: number
          }
          properties?: Record<string, any>
        }
        ```
        
        Good:
        
        ```typescript
        interface FileConfigOptions {
          fileConfig: {
            path: string
            encoding?: string
          }
          properties?: Record<string, any>
        }
        
        interface DbConfigOptions {
          dbConfig: {
            connectionString: string
            poolSize?: number
          }
          properties?: Record<string, any>
        }
        
        type ConfigOptions = FileConfigOptions | DbConfigOptions
        ```

Install this rule for Greptile

Greptile rules can be added through the web interface. Please see this documentation for details on how to add custom rules and context.

Use union types with specific interfaces for mutually exclusive properties instead of a single interface with multiple optional properties.
Bad:
```typescript
interface ConfigOptions {
  fileConfig?: {
    path: string
    encoding?: string
  }
  dbConfig?: {
    connectionString: string
    poolSize?: number
  }
  properties?: Record<string, any>
}
```
Good:
```typescript
interface FileConfigOptions {
  fileConfig: {
    path: string
    encoding?: string
  }
  properties?: Record<string, any>
}
interface DbConfigOptions {
  dbConfig: {
    connectionString: string
    poolSize?: number
  }
  properties?: Record<string, any>
}
type ConfigOptions = FileConfigOptions | DbConfigOptions
```

File Path Patterns:

*.ts
*.tsx

Install this rule for GitHub Copilot

Copilot instructions can be added through the interface. See the documentation for details on how to create coding guidelines.

Use union types with specific interfaces for mutually exclusive properties instead of a single interface with multiple optional properties.
Bad:
```typescript
interface ConfigOptions {
  fileConfig?: {
    path: string
    encoding?: string
  }
  dbConfig?: {
    connectionString: string
    poolSize?: number
  }
  properties?: Record<string, any>
}
```
Good:
```typescript
interface FileConfigOptions {
  fileConfig: {
    path: string
    encoding?: string
  }
  properties?: Record<string, any>
}
interface DbConfigOptions {
  dbConfig: {
    connectionString: string
    poolSize?: number
  }
  properties?: Record<string, any>
}
type ConfigOptions = FileConfigOptions | DbConfigOptions
```

File Path Patterns:

*.ts
*.tsx

Install this rule for Graphite Diamond

Diamond custom rules can be added through the interface. See the documentation for details on how to create custom rules.

Use union types with specific interfaces for mutually exclusive properties instead of a single interface with multiple optional properties.
Bad:
```typescript
interface ConfigOptions {
  fileConfig?: {
    path: string
    encoding?: string
  }
  dbConfig?: {
    connectionString: string
    poolSize?: number
  }
  properties?: Record<string, any>
}
```
Good:
```typescript
interface FileConfigOptions {
  fileConfig: {
    path: string
    encoding?: string
  }
  properties?: Record<string, any>
}
interface DbConfigOptions {
  dbConfig: {
    connectionString: string
    poolSize?: number
  }
  properties?: Record<string, any>
}
type ConfigOptions = FileConfigOptions | DbConfigOptions
```

File Path Patterns:

*.ts
*.tsx

Use with Cline

Copy the rule below and ask Cline to review your code using this rule

Use union types with specific interfaces for mutually exclusive properties instead of a single interface with multiple optional properties.
Bad:
```typescript
interface ConfigOptions {
  fileConfig?: {
    path: string
    encoding?: string
  }
  dbConfig?: {
    connectionString: string
    poolSize?: number
  }
  properties?: Record<string, any>
}
```
Good:
```typescript
interface FileConfigOptions {
  fileConfig: {
    path: string
    encoding?: string
  }
  properties?: Record<string, any>
}
interface DbConfigOptions {
  dbConfig: {
    connectionString: string
    poolSize?: number
  }
  properties?: Record<string, any>
}
type ConfigOptions = FileConfigOptions | DbConfigOptions
```

Use with OpenAI Codex

Copy the rule below and ask OpenAI Codex to review your code using this rule

Use union types with specific interfaces for mutually exclusive properties instead of a single interface with multiple optional properties.
Bad:
```typescript
interface ConfigOptions {
  fileConfig?: {
    path: string
    encoding?: string
  }
  dbConfig?: {
    connectionString: string
    poolSize?: number
  }
  properties?: Record<string, any>
}
```
Good:
```typescript
interface FileConfigOptions {
  fileConfig: {
    path: string
    encoding?: string
  }
  properties?: Record<string, any>
}
interface DbConfigOptions {
  dbConfig: {
    connectionString: string
    poolSize?: number
  }
  properties?: Record<string, any>
}
type ConfigOptions = FileConfigOptions | DbConfigOptions
```

Use with Cursor

Copy the rule below and ask Cursor to review your code using this rule

Use union types with specific interfaces for mutually exclusive properties instead of a single interface with multiple optional properties.
Bad:
```typescript
interface ConfigOptions {
  fileConfig?: {
    path: string
    encoding?: string
  }
  dbConfig?: {
    connectionString: string
    poolSize?: number
  }
  properties?: Record<string, any>
}
```
Good:
```typescript
interface FileConfigOptions {
  fileConfig: {
    path: string
    encoding?: string
  }
  properties?: Record<string, any>
}
interface DbConfigOptions {
  dbConfig: {
    connectionString: string
    poolSize?: number
  }
  properties?: Record<string, any>
}
type ConfigOptions = FileConfigOptions | DbConfigOptions
```

Use with Claude Code

Copy the rule below and ask Claude Code to review your code using this rule

Use union types with specific interfaces for mutually exclusive properties instead of a single interface with multiple optional properties.
Bad:
```typescript
interface ConfigOptions {
  fileConfig?: {
    path: string
    encoding?: string
  }
  dbConfig?: {
    connectionString: string
    poolSize?: number
  }
  properties?: Record<string, any>
}
```
Good:
```typescript
interface FileConfigOptions {
  fileConfig: {
    path: string
    encoding?: string
  }
  properties?: Record<string, any>
}
interface DbConfigOptions {
  dbConfig: {
    connectionString: string
    poolSize?: number
  }
  properties?: Record<string, any>
}
type ConfigOptions = FileConfigOptions | DbConfigOptions
```

Install this rule for Windsurf

To set up rules for Windsurf Reviews, please see this documentation 

Use union types with specific interfaces for mutually exclusive properties instead of a single interface with multiple optional properties.
Bad:
```typescript
interface ConfigOptions {
  fileConfig?: {
    path: string
    encoding?: string
  }
  dbConfig?: {
    connectionString: string
    poolSize?: number
  }
  properties?: Record<string, any>
}
```
Good:
```typescript
interface FileConfigOptions {
  fileConfig: {
    path: string
    encoding?: string
  }
  properties?: Record<string, any>
}
interface DbConfigOptions {
  dbConfig: {
    connectionString: string
    poolSize?: number
  }
  properties?: Record<string, any>
}
type ConfigOptions = FileConfigOptions | DbConfigOptions
```