Run results for: true copy

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/84.0.4147.135 Safari/537.36

Browser: Chrome 84

Operating system: Mac OS X 10.15.5

Device Platform: Desktop

Date tested: 3 years ago

Test name	Executions per second
Array.prototype.slice	13817980.0 Ops/sec
Array.prototype.concat	4033618.0 Ops/sec
spread operator	12598040.0 Ops/sec
Array.from	3687524.0 Ops/sec

Script Preparation code:

const featured = ['Deep dish', 'Peperoni', 'Hawaiian'];
const specialty = ['Meatzza', 'Spicy Nama', 'Margherita'];

let pizzas = [...featured, 'veg', ...specialty];

Tests:

Array.prototype.slice
const featured = ['Deep dish', 'Peperoni', 'Hawaiian']; const specialty = ['Meatzza', 'Spicy Nama', 'Margherita']; let pizzas = [...featured, 'veg', ...specialty]; const copyPizzas1 = pizzas.slice();
Array.prototype.concat
const featured = ['Deep dish', 'Peperoni', 'Hawaiian']; const specialty = ['Meatzza', 'Spicy Nama', 'Margherita']; let pizzas = [...featured, 'veg', ...specialty]; const copyPizzas2 = [].concat(pizzas);
spread operator
const featured = ['Deep dish', 'Peperoni', 'Hawaiian']; const specialty = ['Meatzza', 'Spicy Nama', 'Margherita']; let pizzas = [...featured, 'veg', ...specialty]; const copyPizzas3 = [...pizzas];
Array.from
const featured = ['Deep dish', 'Peperoni', 'Hawaiian']; const specialty = ['Meatzza', 'Spicy Nama', 'Margherita']; let pizzas = [...featured, 'veg', ...specialty]; const copyPizzas4 = Array.from(pizzas);

Array.prototype.slice

Array.prototype.concat

spread operator

Array.from