desc: Tests randomization functions
tests:
    - cd: r.expr([1,2,3]).sample(3).distinct().count()
      ot: 3
    - cd: r.expr([1,2,3]).sample(3).count()
      ot: 3
    - cd: r.expr([1,2,3,4,5,6]).sample(3).distinct().count()
      ot: 3
    - cd: r.expr([1,2,3]).sample(4).distinct().count()
      ot: 3
    - rb: r.expr([[1,2,3], 2]).do{|x| x[0].sample(x[1])}.distinct().count()
      ot: 2
    - cd: r.expr([1,2,3]).sample(-1)
      ot: err('RqlRuntimeError', 'Number of items to sample must be non-negative, got `-1`.', [0])
    - cd: r.expr(1).sample(1)
      ot: err('RqlRuntimeError', 'Cannot convert NUMBER to SEQUENCE', [0])
    - cd: r.expr({}).sample(1)
      ot: err('RqlRuntimeError', 'Cannot convert OBJECT to SEQUENCE', [0])
