source: frontend/node_modules/parent-module/index.js

'use strict';
const callsites = require('callsites');

module.exports = filepath => {
        const stacks = callsites();

        if (!filepath) {
                return stacks[2].getFileName();
        }

        let seenVal = false;

        // Skip the first stack as it's this function
        stacks.shift();

        for (const stack of stacks) {
                const parentFilepath = stack.getFileName();

                if (typeof parentFilepath !== 'string') {
                        continue;
                }

                if (parentFilepath === filepath) {
                        seenVal = true;
                        continue;
                }

                // Skip native modules
                if (parentFilepath === 'module.js') {
                        continue;
                }

                if (seenVal && parentFilepath !== filepath) {
                        return parentFilepath;
                }
        }
};