@graphql-eslint/eslint-plugin/esm/rules/no-one-place-fragments/index.js

GraphQL plugin for ESLint

import { relative } from "node:path";
import { visit } from "graphql";
import { CWD, requireGraphQLOperations } from "../../utils.js";
const RULE_ID = "no-one-place-fragments";
const rule = {
  meta: {
    type: "suggestion",
    docs: {
      category: "Operations",
      description: "Disallow fragments that are used only in one place.",
      url: `https://the-guild.dev/graphql/eslint/rules/${RULE_ID}`,
      examples: [
        {
          title: "Incorrect",
          code: (
            /* GraphQL */
            `
            fragment UserFields on User {
              id
            }

            {
              user {
                ...UserFields
              }
            }
          `
          )
        },
        {
          title: "Correct",
          code: (
            /* GraphQL */
            `
            fragment UserFields on User {
              id
            }

            {
              user {
                ...UserFields
                friends {
                  ...UserFields
                }
              }
            }
          `
          )
        }
      ],
      requiresSiblings: true
    },
    messages: {
      [RULE_ID]: 'Fragment `{{fragmentName}}` used only once. Inline him in "{{filePath}}".'
    },
    schema: []
  },
  create(context) {
    const operations = requireGraphQLOperations(RULE_ID, context);
    const allDocuments = [...operations.getOperations(), ...operations.getFragments()];
    const usedFragmentsMap = /* @__PURE__ */ Object.create(null);
    for (const { document, filePath } of allDocuments) {
      const relativeFilePath = relative(CWD, filePath);
      visit(document, {
        FragmentSpread({ name }) {
          const spreadName = name.value;
          usedFragmentsMap[spreadName] ||= [];
          usedFragmentsMap[spreadName].push(relativeFilePath);
        }
      });
    }
    return {
      "FragmentDefinition > Name"(node) {
        const fragmentName = node.value;
        const fragmentUsage = usedFragmentsMap[fragmentName];
        if (fragmentUsage.length === 1) {
          context.report({
            node,
            messageId: RULE_ID,
            data: { fragmentName, filePath: fragmentUsage[0] }
          });
        }
      }
    };
  }
};
export {
  rule
};