translation using arrays does not work

[deeplcom]

translation using arrays does not work

[daniel-jones-deepl]

Hi @LorenzoJokhan, thanks for creating the issue.

Unfortunately I haven't been able to reproduce this. The library includes this test case in the tests. Are you using a supported node version?

[LorenzoJokhan]

I am using version v16.17.1

[LorenzoJokhan]

Ik heb in de functie appendTextsAndReturnIsSingular(data, texts) wat console logs gedaan en krijg het volgende:

console.log({textsIsArray:Array.isArray(texts)});
console.log({arrayToTranslate:texts});
for (const key in texts) {
console.log(key);
}

wat dit geeft
{ textsIsArray: true }
{ arrayToTranslate: [ 'tekst', 'welkom' ] }
keys: 0, 1, insert

error: DeepLError: texts parameter must not be a non-empty string or array of non-empty strings

[daniel-jones-deepl]

Thanks, but I could not reproduce this behavior either; the key "insert" does not appear. Does the texts array come from an unusual source?

[LorenzoJokhan]

No, i am directly passing this array in the function:

translator.translateText(
['hallo', 'test'],
req.body.sourceLanguageCode, //this is nl
req.body.targetLanguageCode, // this is en-GB
)

as soon as i change the code to a for..of loop then it works on my side with response:

response: [
{ text: 'text', detectedSourceLang: 'nl' },
{ text: 'welcome', detectedSourceLang: 'nl' }
]

[LorenzoJokhan]

It seems a developer at my current project added a key to the prototype of array (which is not a good thing to do). Meaning that every array at our side will have that function as a key. This would mean however that if you choose to continue to use a for...in loop in deepl translation, then in the future when another library modifies the prototype they will also have these issues.

Array.prototype.insert = function ( index, item ) {
this.splice( index, 0, item );
};

The easiest fool-proof fix would be to change the loop to a for...of loop or standard for loop that only iterates over the elements instead of the keys (also mdn advises against using for..in for looping over elements https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration#for...in_statement)

[daniel-jones-deepl]

Thank you for your reply, that explains the cause.

You are right about using for .. of loops, we'll fix this soon.

[daniel-jones-deepl]

This is fixed in v1.7.1.