bbc/simorgh

import flattenGroups from './flattenGroups';

describe('flattenGroups', () => {
  it('should return an empty array when groups is an empty array', () => {
    expect(flattenGroups([])).toStrictEqual([]);
  });

  it('should return an array when groups has 1 item', () => {
    const groups = [{}];
    expect(flattenGroups(groups)).toStrictEqual([{}]);
  });

  it('should return an array when all groups have a strapline', () => {
    const groups = [
      { strapline: { name: 'strapline 1' } },
      { strapline: { name: 'strapline 2' } },
    ];
    expect(flattenGroups(groups)).toStrictEqual([
      { strapline: { name: 'strapline 1' } },
      { strapline: { name: 'strapline 2' } },
    ]);
  });

  it('should move items from a group without a strapline into a group with a strapline', () => {
    const groups = [
      { strapline: { name: 'strapline 1' }, items: [{ id: '1' }, { id: '2' }] },
      { items: [{ id: '3' }, { id: '4' }] },
    ];
    expect(flattenGroups(groups)).toStrictEqual([
      {
        strapline: { name: 'strapline 1' },
        items: [{ id: '1' }, { id: '2' }, { id: '3' }, { id: '4' }],
      },
    ]);
  });

  it('should move items from multiple groups without a strapline into groups with a strapline', () => {
    const groups = [
      { items: [{ id: '1' }, { id: '2' }, { id: '3' }, { id: '4' }] },
      { items: [{ id: '4' }, { id: '5' }, { id: '6' }] },
      {
        strapline: { name: 'strapline 3' },
        items: [{ id: '10' }, { id: '15' }],
      },
      { items: [{ id: '20' }, { id: '25' }] },
      {
        strapline: { name: 'strapline 5' },
        items: [{ id: '30' }, { id: '40' }],
      },
      { items: [{ id: '100' }, { id: '200' }] },
    ];
    expect(flattenGroups(groups)).toStrictEqual([
      {
        items: [
          { id: '1' },
          { id: '2' },
          { id: '3' },
          { id: '4' },
          { id: '5' },
          { id: '6' },
        ],
      },
      {
        strapline: { name: 'strapline 3' },
        items: [{ id: '10' }, { id: '15' }, { id: '20' }, { id: '25' }],
      },
      {
        strapline: { name: 'strapline 5' },
        items: [{ id: '30' }, { id: '40' }, { id: '100' }, { id: '200' }],
      },
    ]);
  });
});