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// 11: destructuring - string
// To do: make all tests pass, leave the assert lines unchanged!

describe('destructuring also works on strings', () => {

  
  it('destructure every character', () => {
    let [a, b, c] = 'abc';
    assert.deepEqual([a, b, c], ['a', 'b', 'c']);
  });

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// 12: destructuring - object
// To do: make all tests pass, leave the assert lines unchanged!

describe('destructuring objects', () => {

  it('is simple', () => {
    const {x} = {x: 1};
    assert.equal(x, 1);
  });

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describe('destructuring can also have default values', () => {

  it('for an empty array', () => {
    const [a=1] = [];
    assert.equal(a, 1);
  });

  it('for a missing value', () => {
    const [,b=2,] = [1,,3];
    assert.equal(b, 2);

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// 14: destructuring - parameters
// To do: make all tests pass, leave the assert lines unchanged!

describe('destructuring function parameters', () => {

  describe('destruct parameters', () => {
    it('multiple params from object', () => {
      const fn = ({id,name}) => {
        assert.equal(id, 42);
        assert.equal(name, 'Wolfram');

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// 15: destructuring - assign
// To do: make all tests pass, leave the assert lines unchanged!

describe('assign object property values to new variables while destructuring', () => {

  describe('for simple objects', function() {
    it('use a colon after the property name, like so `propertyName: newName`', () => {
      const {x: newName} = {x: 1};
      assert.equal(newName, 1);
    });

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// 16: object-literal - computed properties
// To do: make all tests pass, leave the assert lines unchanged!

describe('Object literal properties may be computed values', () => {

  it('a computed property `x` needs to be surrounded by `[]`', () => {
    const propertyName = 'x';
    const obj = {[propertyName]: 1};
    assert.equal(obj.x, 1);
  });

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// 17: unicode - in strings
// To do: make all tests pass, leave the assert lines unchanged!

describe('unicode strings', () => {

  it('are \\u prefixed', () => {
    const nuclear = '\u2622';
    assert.equal(nuclear, '☢');
  });

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// 18: rest - as-parameter
// To do: make all tests pass, leave the assert lines unchanged!

describe('rest in function params', () => {
    
  it('must be the last parameter', () => {
    const fn = (...rest) => {
      assert.deepEqual([1, 2], rest);
    };
    fn(1, 2);

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// 19: rest - with-destructuring
// To do: make all tests pass, leave the assert lines unchanged!

describe('rest with destructuring', () => {
    
  it('rest parameter must be last', () => {
    const [...all] = [1, 2, 3, 4];
    assert.deepEqual(all, [1, 2, 3, 4]);
  });
  

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// 20: spread - with-arrays
// To do: make all tests pass, leave the assert lines unchanged!

describe('spread with arrays', () => {

  it('extracts each array item', function() {
    const [a, b] = [...[1, 2]];
    assert.equal(a, 1);
    assert.equal(b, 2);
  });