Function in JS that return defined data with 1 second delay-CodePudding

So,i have a task,to make a function 'mocker' which will return defined data with 1 second delay.The problem is that i'm new in JavaScript world and idk how to do this.I tried to take this way:

mocker = function mocker(data) {
    var delayInMilliseconds = 1000;
    setTimeout(function () {
        return data;
    }, delayInMilliseconds);};

But it doesnt satisfy the assignment. I have this example :

 const getUsers = mocker([{id: 1, name: 'User1'}]);
getUsers().then((users) => { // Will fire after 1 second.
  console.log(users); // result: [{id: 1, name: 'User1'}];
});

And this is function description for test :

describe('mocker', () => {
describe('users mocker', () => {
    const usersData = [{id: 1, login: 'mickey'}, {id: 2, login: 'billy77'}, {id: 3, login: 'coooool123'}];
    let getUsers;

    beforeEach(() => {
        getUsers = mocker(usersData);
    });

    it('should return users data', async () => {
        const resultData = await getUsers();
        assert.deepStrictEqual(resultData, usersData);
    });

    it('should return users data in asynchronous way', () => {
        const resultData = getUsers();
        assert.notDeepStrictEqual(resultData, usersData);
    });
});

});

@param data: {Array | Object}
@returns {Function}

Can you guys please help me? Thanks in advance.

CodePudding user response：

The test suggests it's a little more complicated than just creating a function that returns some data after a second.

This line:

getUsers = mocker(usersData);

is saying that mocker needs to 1) accept some data and 2) return a function that we assign to getUsers. When we call getUsers it will then call that function to return the promise of data.

So when we get here:

const resultData = await getUsers();

we're calling that function we assigned to getUsers that promises to return some data (or not) after a second.

const usersData = [{id: 1, login: 'mickey'}, {id: 2, login: 'billy77'}, {id: 3, login: 'coooool123'}];

// `mocker` accepts some data and returns a
// function. This function is assigned to `getData`, and
// when `getData` is called this is the function that gets executed.
// It returns a promise that after one second data will be returned.
function mocker(usersData) {
  return function () {
    return new Promise((res, rej) => {
      setTimeout(() => res(usersData), 1000);
    });
  }
}

// So we call `mocker` and assign the function it
// returns to `getUsers`
const getUsers = mocker(usersData);

async function main() {

  // We can then call `getUsers` to get the data
  // after one second has passed
  console.log(await getUsers());
}

main();

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