text: const valid = require("../isValid");
  
  describe('valid function' , function(){
    let mat;
    it('should return false if matrix is not valid' , function(){
      mat = 1;
      expect(valid(mat)).toEqual(false);
      mat = {};
      expect(valid(mat)).toEqual(false);
      mat = [];
      expect(valid(mat)).toEqual(false);
    }); 
    
    it('should return true if passed matrix is valid' , function(){
      mat = [1];
      expect(valid(mat)).toEqual(true);
    });
  
  
  })