I’m currently building a small command-line tool with Node and node-xlsx to parse and process some Excel files, and I noticed that whenever the input contains the sequence

_X2069_

node-xlsx seems to convert it to Unicode character U+2069 (Pop Directional Isolate).

Here’s a minimal example:

const xlsx = require('node-xlsx');

function getData(excelSheet) {
    data = [];
    excelData = excelSheet[0]["data"]
    length = 0
    // Find the number of rows with actual data and filter out blank rows at the end
    for (let i = 0; i < excelData.length; i++) {
        if (excelData[i][0] != undefined) {
          data.push([]);
          data[i].push(excelData[i][0]); // only first column for now
        }
    }
    return data;
}

const workSheet = xlsx.parse('./input.xlsx');
let rows = getData(workSheet);
console.log(rows);

And here’s my input (contents of input.xlsx):

_X2069_
_Y2069_
_Z2069_

The output is:

[ [ 'u2069⁩' ], [ '_Y2069_' ], [ '_Z2069_' ]

which appears like:

My current workaround is to replace all occurrences of U+2069 with the original string, but that seems hacky, and I’m afraid that 2069 isn’t the only value that is automagically converted.

How can I prevent this erroneous conversion?