Check that array does not contain falsy values in Jest

I am trying to create a unit test with Jest to make sure my array called values does not contain falsy values.

values

This for some reason does not work - the test passes:

const badValues = ['', null, undefined, false, , ];
expect(values).toEqual(expect.not.arrayContaining(badValues));


Below code works as expected (test fails), but surely there must be a proper way instead of looping over my values?

for (const value of values)
expect(value).toBeTruthy();



== false

? alert("truthy") : alert("falsy")

==

2 Answers
2

It is possible iterating over badValues and then includes() if values and badValues are both arrays of strings or numbers, not objects.

badValues

includes()

values

badValues

const badValues = ['', 'null', 'undefined', 'false', '', ''];

var values = [1,2,3,4,'null',5];


for(let i = 0; i<badValues.length; i++)

if(values.includes(badValues[i]))
console.log("bad value present");
break;




Otherwise, I think there is no better way than iterating over values. It could be possible using test() and regex, but [,],, are all special characters in regex expressions. So we should escape them.

values

test()

[

]

===

===

.includes

May be this can work:

var isValid = arrayOfValuesToBeChecked.reduce(function(prev, elem)
// If elem is not truthy and if it is object, check its length
elem = elem ? typeof(elem) == 'object' ? elem instanceof Array ? elem.length : Object.keys(elem).length : elem : elem;
return prev && elem;
, true);


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