/**
 * npm install source-map
 * node ParseMap.js
 */ 
var sourceMap = require('source-map');
var fs = require('fs');

var rawSourceMap = JSON.parse(fs.readFileSync('test.bundle.map', 'utf8'));

const whatever = sourceMap.SourceMapConsumer.with(rawSourceMap, null, consumer => {
  console.log(consumer.originalPositionFor({
    line: 577,
    column: 2554
  }));
});