filter of Filter in javascript array

Question

I have an array that I'm trying to filter:

const elements = ['apple'];

const objects = [
  { id: 1, fruit:[{"name": "apple" },{"name": "banana" }]},
  { id: 2, fruit:[{"name": "apple" },{"name": "orange" }]},
  { id: 3, fruit:[{"name": "orange" },{"name": "banana" }]},
  { id: 4, fruit:[{"name": "orange" },{"name": "banana" }]}
];

const results = objects.filter(obj => obj.fruit.filter( ele => elements.includes(ele.name)));
console.log(results);

I am getting the output as below but this not what I am expecting:

{id: 1, fruit:[{"name": "apple" },{"name": "banana" }]
{id: 2, fruit:[{"name": "apple" },{"name": "banana" }]

I want the output as below:

{ id: 1, fruit:[{"name": "apple" }]}
{ id: 2, fruit:[{"name": "apple" }]}

Answer 1

You could filter fruit and if it has elements take the outer object as result.

const
    elements = ['apple'],
    objects = [{ id: 1, fruit: [{ name: "apple" }, { name: "banana" }] }, { id: 2, fruit: [{ name: "apple" }, { name: "orange" }] }, { id: 3, fruit: [{ name: "orange" }, { name: "banana" }] }, { id: 4, fruit: [{ name: "orange" }, { name: "banana" }] }],
    results = objects.reduce((r, o) => {
        const fruit = o.fruit.filter(({ name }) => elements.includes(name));
        if (fruit.length) r.push({ ...o, fruit });
        return r;
    }, []);
    
console.log(results);

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