@graphql-mesh/utils/esm/projectResultBySelectionSet.js

export function projectResultBySelectionSet({ result, selectionSet, fragments = {}, }) {
    if (!selectionSet?.selections?.length) {
        return result;
    }
    if (Array.isArray(result)) {
        return result.map(item => projectResultBySelectionSet({ result: item, selectionSet }));
    }
    if (typeof result === 'object' && result != null) {
        const projectedResult = {};
        for (const selection of selectionSet.selections) {
            switch (selection.kind) {
                case 'Field': {
                    const originalFieldName = selection.name.value;
                    const fieldResult = result[originalFieldName];
                    if (fieldResult == null) {
                        projectedResult[originalFieldName] = null;
                        break;
                    }
                    const responseKey = selection.alias?.value || originalFieldName;
                    projectedResult[responseKey] = projectResultBySelectionSet({
                        result: fieldResult,
                        selectionSet: selection.selectionSet,
                        fragments,
                    });
                    break;
                }
                case 'FragmentSpread': {
                    const fragmentName = selection.name.value;
                    const fragment = fragments[fragmentName];
                    if (!fragment) {
                        throw new Error(`Fragment ${fragmentName} not found`);
                    }
                    Object.assign(projectedResult, projectResultBySelectionSet({ result, selectionSet: fragment.selectionSet, fragments }));
                    break;
                }
                case 'InlineFragment': {
                    Object.assign(projectedResult, projectResultBySelectionSet({
                        result,
                        selectionSet: selection.selectionSet,
                        fragments,
                    }));
                    break;
                }
                default:
                    throw new Error(`Unsupported selection kind ${selection.kind}`);
            }
        }
        return projectedResult;
    }
    return result;
}