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Passing arrays to cx results in a className string with commas

See original GitHub issue

sample code here: https://github.com/brianbegy/classnames-array-poc

const cx = require("classnames");

function returnsAnArray() {
  return ["arrays", "have", "commas"];
}

console.log(cx("strings", { ["are"]: true }, { ["ok"]: true }));
console.log(cx("but", { [returnsAnArray()]: true }));

expected result: strings are ok but arrays have commas

actual result: strings are ok but arrays,have,commas

Is this the intended behavior?

Issue Analytics

State:
Created 4 years ago
Comments:5

Top GitHub Comments

2reactions

newyork-anthonyngcommented, Oct 8, 2019

@brianbegy the default behavior of JavaScript is:

if an array is an Object’s key
convert each array element into a string
and join them together with commas

function returnsAnArray() {
  return ["arrays", "have", "commas",{}];
}

const myObject = { [returnsAnArray()]: true }
console.log(Object.keys(myObject)); // ['arrays,have,commas,[object Object]']

The commas seem to be something related to JavaScript, and not this package.

1reaction

brianbegycommented, Sep 26, 2019

Having looked through the code and written a solution, it is pretty obvious that “fixing” it would have a serious performance cost.

I’ll leave this open for the moment, but this looks like a “won’t fix” to me.