@graphql-eslint/eslint-plugin/esm/rules/relay-connection-types/index.js

GraphQL plugin for ESLint

import { Kind } from "graphql";
const MUST_BE_OBJECT_TYPE = "MUST_BE_OBJECT_TYPE", MUST_CONTAIN_FIELD_EDGES = "MUST_CONTAIN_FIELD_EDGES", MUST_CONTAIN_FIELD_PAGE_INFO = "MUST_CONTAIN_FIELD_PAGE_INFO", MUST_HAVE_CONNECTION_SUFFIX = "MUST_HAVE_CONNECTION_SUFFIX", EDGES_FIELD_MUST_RETURN_LIST_TYPE = "EDGES_FIELD_MUST_RETURN_LIST_TYPE", PAGE_INFO_FIELD_MUST_RETURN_NON_NULL_TYPE = "PAGE_INFO_FIELD_MUST_RETURN_NON_NULL_TYPE", NON_OBJECT_TYPES = [
  Kind.SCALAR_TYPE_DEFINITION,
  Kind.UNION_TYPE_DEFINITION,
  Kind.UNION_TYPE_EXTENSION,
  Kind.INPUT_OBJECT_TYPE_DEFINITION,
  Kind.INPUT_OBJECT_TYPE_EXTENSION,
  Kind.ENUM_TYPE_DEFINITION,
  Kind.ENUM_TYPE_EXTENSION,
  Kind.INTERFACE_TYPE_DEFINITION,
  Kind.INTERFACE_TYPE_EXTENSION
], notConnectionTypesSelector = `:matches(${NON_OBJECT_TYPES})[name.value=/Connection$/] > .name`, hasEdgesField = (node) => node.fields?.some((field) => field.name.value === "edges"), hasPageInfoField = (node) => node.fields?.some((field) => field.name.value === "pageInfo"), rule = {
  meta: {
    type: "problem",
    docs: {
      category: "Schema",
      description: [
        "Set of rules to follow Relay specification for Connection types.",
        "",
        '- Any type whose name ends in "Connection" is considered by spec to be a `Connection type`',
        "- Connection type must be an Object type",
        "- Connection type must contain a field `edges` that return a list type that wraps an edge type",
        "- Connection type must contain a field `pageInfo` that return a non-null `PageInfo` Object type"
      ].join(`
`),
      url: "https://the-guild.dev/graphql/eslint/rules/relay-connection-types",
      isDisabledForAllConfig: !0,
      examples: [
        {
          title: "Incorrect",
          code: (
            /* GraphQL */
            `
            type UserPayload { # should be an Object type with \`Connection\` suffix
              edges: UserEdge! # should return a list type
              pageInfo: PageInfo # should return a non-null \`PageInfo\` Object type
            }
          `
          )
        },
        {
          title: "Correct",
          code: (
            /* GraphQL */
            `
            type UserConnection {
              edges: [UserEdge]
              pageInfo: PageInfo!
            }
          `
          )
        }
      ]
    },
    messages: {
      // Connection types
      [MUST_BE_OBJECT_TYPE]: "Connection type must be an Object type.",
      [MUST_HAVE_CONNECTION_SUFFIX]: "Connection type must have `Connection` suffix.",
      [MUST_CONTAIN_FIELD_EDGES]: "Connection type must contain a field `edges` that return a list type.",
      [MUST_CONTAIN_FIELD_PAGE_INFO]: "Connection type must contain a field `pageInfo` that return a non-null `PageInfo` Object type.",
      [EDGES_FIELD_MUST_RETURN_LIST_TYPE]: "`edges` field must return a list type.",
      [PAGE_INFO_FIELD_MUST_RETURN_NON_NULL_TYPE]: "`pageInfo` field must return a non-null `PageInfo` Object type."
    },
    schema: []
  },
  create(context) {
    return {
      [notConnectionTypesSelector](node) {
        context.report({ node, messageId: MUST_BE_OBJECT_TYPE });
      },
      ":matches(ObjectTypeDefinition, ObjectTypeExtension)[name.value!=/Connection$/]"(node) {
        hasEdgesField(node) && hasPageInfoField(node) && context.report({ node: node.name, messageId: MUST_HAVE_CONNECTION_SUFFIX });
      },
      ":matches(ObjectTypeDefinition, ObjectTypeExtension)[name.value=/Connection$/]"(node) {
        hasEdgesField(node) || context.report({ node: node.name, messageId: MUST_CONTAIN_FIELD_EDGES }), hasPageInfoField(node) || context.report({ node: node.name, messageId: MUST_CONTAIN_FIELD_PAGE_INFO });
      },
      ":matches(ObjectTypeDefinition, ObjectTypeExtension)[name.value=/Connection$/] > FieldDefinition[name.value=edges] > .gqlType"(node) {
        node.kind === Kind.LIST_TYPE || node.kind === Kind.NON_NULL_TYPE && node.gqlType.kind === Kind.LIST_TYPE || context.report({ node, messageId: EDGES_FIELD_MUST_RETURN_LIST_TYPE });
      },
      ":matches(ObjectTypeDefinition, ObjectTypeExtension)[name.value=/Connection$/] > FieldDefinition[name.value=pageInfo] > .gqlType"(node) {
        node.kind === Kind.NON_NULL_TYPE && node.gqlType.kind === Kind.NAMED_TYPE && node.gqlType.name.value === "PageInfo" || context.report({ node, messageId: PAGE_INFO_FIELD_MUST_RETURN_NON_NULL_TYPE });
      }
    };
  }
};
export {
  NON_OBJECT_TYPES,
  rule
};