@graphql-codegen/client-preset/esm/fragment-masking-plugin.js

GraphQL Code Generator preset for client.

const fragmentTypeHelper = `
export type FragmentType<TDocumentType extends DocumentNode<any, any>> = TDocumentType extends DocumentNode<
  infer TType,
  any
>
  ? TType extends { ' $fragmentName'?: infer TKey }
    ? TKey extends string
      ? { ' $fragmentRefs'?: { [key in TKey]: TType } }
      : never
    : never
  : never;`;
const makeFragmentDataHelper = `
export function makeFragmentData<
  F extends DocumentNode,
  FT extends ResultOf<F>
>(data: FT, _fragment: F): FragmentType<F> {
  return data as FragmentType<F>;
}`;
const defaultUnmaskFunctionName = 'useFragment';
const modifyType = (rawType, opts) => `${opts.list === 'only-list'
    ? `ReadonlyArray<${rawType}>`
    : opts.list === 'with-list'
        ? `${rawType} | ReadonlyArray<${rawType}>`
        : rawType}${opts.nullable ? ' | null | undefined' : ''}`;
const createUnmaskFunctionTypeDefinition = (unmaskFunctionName = defaultUnmaskFunctionName, opts) => `export function ${unmaskFunctionName}<TType>(
  _documentNode: DocumentNode<TType, any>,
  fragmentType: ${modifyType('FragmentType<DocumentNode<TType, any>>', opts)}
): ${modifyType('TType', opts)}`;
const createUnmaskFunctionTypeDefinitions = (unmaskFunctionName = defaultUnmaskFunctionName) => [
    `// return non-nullable if \`fragmentType\` is non-nullable\n${createUnmaskFunctionTypeDefinition(unmaskFunctionName, { nullable: false, list: false })}`,
    `// return nullable if \`fragmentType\` is nullable\n${createUnmaskFunctionTypeDefinition(unmaskFunctionName, {
        nullable: true,
        list: false,
    })}`,
    `// return array of non-nullable if \`fragmentType\` is array of non-nullable\n${createUnmaskFunctionTypeDefinition(unmaskFunctionName, { nullable: false, list: 'only-list' })}`,
    `// return array of nullable if \`fragmentType\` is array of nullable\n${createUnmaskFunctionTypeDefinition(unmaskFunctionName, { nullable: true, list: 'only-list' })}`,
];
const createUnmaskFunction = (unmaskFunctionName = defaultUnmaskFunctionName) => `
${createUnmaskFunctionTypeDefinitions(unmaskFunctionName)
    .concat(createUnmaskFunctionTypeDefinition(unmaskFunctionName, { nullable: true, list: 'with-list' }))
    .join(';\n')} {
  return fragmentType as any;
}
`;
/**
 * Plugin for generating fragment masking helper functions.
 */
export const plugin = (_, __, { useTypeImports, augmentedModuleName, unmaskFunctionName }, _info) => {
    const documentNodeImport = `${useTypeImports ? 'import type' : 'import'} { TypedDocumentNode as DocumentNode, ResultOf } from '@graphql-typed-document-node/core';\n`;
    if (augmentedModuleName == null) {
        return [
            documentNodeImport,
            `\n`,
            fragmentTypeHelper,
            `\n`,
            createUnmaskFunction(unmaskFunctionName),
            `\n`,
            makeFragmentDataHelper,
        ].join(``);
    }
    return [
        documentNodeImport,
        `declare module "${augmentedModuleName}" {`,
        [
            ...fragmentTypeHelper.split(`\n`),
            `\n`,
            ...createUnmaskFunctionTypeDefinitions(unmaskFunctionName).join('\n').split('\n'),
            `\n`,
            makeFragmentDataHelper,
        ]
            .map(line => (line === `\n` || line === '' ? line : `  ${line}`))
            .join(`\n`),
        `}`,
    ].join(`\n`);
};