array .includes() giving unexpected behavior

Question

I have a very simple array and am checking to see if it .includes() a value. But it is not returning the result I expect.

var myArray = [['noca', 'North Cascades National Park'], ['shen', 'Shenandoah National Park']];

var myItem = ['noca', 'North Cascades National Park'];

myArray.includes(myItem);   //returns false

Why is myArray.inclues(myItem) returning false? This seems like the simplest thing in the world. It should return true.

Answer 1

Checking if an array contains another array is tricky. As I said in the comments, ['noca'] === ['noca'] returns false because these are two distinct arrays.

On the other hand, JSON.stringify(['noca']) === JSON.stringify(['noca']) returns true because it compares two strings, so you can use that :

var myArray = [['noca', 'North Cascades National Park'], ['shen', 'Shenandoah National Park']];
var myItem = ['noca', 'North Cascades National Park'];

const checkContains = (parent, child) => parent.some(arr => JSON.stringify(arr)===JSON.stringify(child))

console.log( checkContains(myArray, myItem) )
console.log( checkContains(myArray, ["test"]) )
console.log( checkContains(myArray, ["noca"]) ) // No false positive (works as intended)

Answer 2

The following is adopted from this answer:

https://stackoverflow.com/a/48538239/2096053

var datas= [
  ["aaa", "bbb"],
  ["ddd", "eee"]
];

function exists(arr, search) {
    return arr.some(row => 
        Array.isArray(row) &&
        Array.isArray(search) &&
        row.length === search.length &&
        row.every((val, index) => val === search[index])
)
};

console.log(exists(datas, ['aaa', 'bbb'])); // TRUE
console.log(exists(datas, ['aaa']));        // FALSE
console.log(exists(datas, ['xxx']));        // FALSE
console.log(exists(datas, 'xxx'));          // FALSE

You need to use a combination of some and includes to properly go over the array.

I have updated this answer to search on arrays.