no-duplicate-fields.md

no-duplicate-fields

✅ The "extends": "plugin:@graphql-eslint/operations-recommended" property in a configuration file enables this rule.

💡 This rule provides suggestions

• Category: Operations
• Rule name: @graphql-eslint/no-duplicate-fields
• Requires GraphQL Schema: false ℹ️
• Requires GraphQL Operations: false ℹ️

Checks for duplicate fields in selection set, variables in operation definition, or in arguments set of a field.

Usage Examples

Incorrect

# eslint @graphql-eslint/no-duplicate-fields: 'error'

query {
  user {
    name
    email
    name # duplicate field
  }
}

Incorrect

# eslint @graphql-eslint/no-duplicate-fields: 'error'

query {
  users(
    first: 100
    skip: 50
    after: "cji629tngfgou0b73kt7vi5jo"
    first: 100 # duplicate argument
  ) {
    id
  }
}

Incorrect

# eslint @graphql-eslint/no-duplicate-fields: 'error'

query (
  $first: Int!
  $first: Int! # duplicate variable
) {
  users(first: $first, skip: 50) {
    id
  }
}

Resources

• Rule source
• Test source