Added key value with value "undefined"

[gnujeremie]

Hi there,

A simple question about the following example :

 const { diff } = require('json-diff-ts');

const a = { bubu: 'bubu', newProp: undefined }
const b = { bubu: 'bubu' }

console.log(diff(b, a))
[ { type: 'ADD', key: 'newProp', value: undefined } ]

Is there a way to treat this case as "nothing changed" ?

I sometimes set some values to undefined in order to remove them from an object, so in this case diff tells me there is an update but my final objects are the same.

[ltwlf]

This is an interesting edge case. Since undefined isn't a valid JSON value, treating {newProp: undefined} and {} as identical is debatable — technically they serialize to the same JSON. For now you can work around this by stripping undefined properties before diffing. Going to flag this as a discussion/enhancement for a future release.