test.js

const typeFinder = type => function* (params = {}, ref = 'master') {
    const search = function* (searchParams) {
        const Api = yield initApi;

        const reference = ref === 'master' ? Api.master() : ref;

        const preparedForm = Api.form('everything')
            .ref(reference)
            .pageSize(200);
        const predicates = [];

        if (type) {
            predicates.push(Prismic.Predicates.at('document.type', type));
            if (searchParams.hasOwnProperty('uid')) {
                predicates.push(Prismic.Predicates.at(`my.${type}.uid`, searchParams.uid));
            }
        }

        if (searchParams.hasOwnProperty('id')) {
            predicates.push(Prismic.Predicates.at('document.id', searchParams.id));
        }

        preparedForm.query(...predicates);
console.log(predicates)
        return yield preparedForm.submit.bind(preparedForm);
    };

console.time('Prismic');
    const response = yield search(params);
console.timeEnd('Prismic');
    if (!response.results.length) {
        const err = new Error(`Unable to find ${type} for ${JSON.stringify(params)}.`);
        err.status = 404;
        throw err;
    }

    return response.results;
};