text: const Block = require('./block');
  
  describe('Block', () => {
      let block, lastBlock, data;
  
      beforeEach(() => {
          data = 'bar';
          lastBlock = Block.genesis();
          block = Block.mineBlock(lastBlock, data);
      });
  
      it('sets the `data` to match the input', () => {
          expect(block.data).toEqual(data);
      });
  
      it('sets the `lastHash` to match the hash of the last block', () => {
          expect(block.lastHash).toEqual(lastBlock.hash);
      });
  });