source: frontend/node_modules/execa/lib/stdio.js

'use strict';
const aliases = ['stdin', 'stdout', 'stderr'];

const hasAlias = options => aliases.some(alias => options[alias] !== undefined);

const normalizeStdio = options => {
        if (!options) {
                return;
        }

        const {stdio} = options;

        if (stdio === undefined) {
                return aliases.map(alias => options[alias]);
        }

        if (hasAlias(options)) {
                throw new Error(`It's not possible to provide \`stdio\` in combination with one of ${aliases.map(alias => `\`${alias}\``).join(', ')}`);
        }

        if (typeof stdio === 'string') {
                return stdio;
        }

        if (!Array.isArray(stdio)) {
                throw new TypeError(`Expected \`stdio\` to be of type \`string\` or \`Array\`, got \`${typeof stdio}\``);
        }

        const length = Math.max(stdio.length, aliases.length);
        return Array.from({length}, (value, index) => stdio[index]);
};

module.exports = normalizeStdio;

// `ipc` is pushed unless it is already present
module.exports.node = options => {
        const stdio = normalizeStdio(options);

        if (stdio === 'ipc') {
                return 'ipc';
        }

        if (stdio === undefined || typeof stdio === 'string') {
                return [stdio, stdio, stdio, 'ipc'];
        }

        if (stdio.includes('ipc')) {
                return stdio;
        }

        return [...stdio, 'ipc'];
};