ladybird/Libraries/LibJS/Tests/functions/function-spread.js

test("basic functionality", () => {
  const sum = (a, b, c) => a + b + c;
  const a = [1, 2, 3];

  expect(sum(...a)).toBe(6);
  expect(sum(1, ...a)).toBe(4);
  expect(sum(...a, 10)).toBe(6);

  const foo = (a, b, c) => c;

  const o = { bar: [1, 2, 3] };
  expect(foo(...o.bar)).toBe(3);
  expect(foo(..."abc")).toBe("c");
});

test("spreading non iterable", () => {
  expect(() => {
    [...1];
  }).toThrowWithMessage(TypeError, "1 is not iterable");
});