Minitest 不会通过，尽管使用 binding.pry 检查标准是正确的

Question

这是被测试的对象

class Ship
attr_reader :size, :x, :y, :axis

def initialize size
    @size = size
end

def length
    @size = size
end

def place x, y, axis
    @x = x
    @y = y
    @axis = axis
end

def covers? a, b
    x = @x
    y = @y

    if x == a and y == b
        return true
    else
        (@size - 1).times do
            if @axis
                x += 1
            else
                y += 1
            end
            return true if x == a and y == b
        end
        false
    end
 end

结束

这个测试会通过

def test_08_ship_can_be_placed_across
    ship = Ship.new(4)
    assert ship.place(2, 1, true)

    assert ship.covers?(2, 1)
    assert ship.covers?(3, 1)
    assert ship.covers?(4, 1)
    assert ship.covers?(5, 1)

    refute ship.covers?(1, 1)
    refute ship.covers?(6, 1)
    refute ship.covers?(4, 2)
 end

这是不会通过的测试

def test_09_ship_can_be_placed_down

    ship = Ship.new(4)
    assert ship.place(2, 2, false)

    refute ship.covers?(2, 1)

    assert ship.covers?(2, 2)
    assert ship.covers?(2, 3)
    assert ship.covers?(2, 4)
    assert ship.covers?(2, 5)

    refute ship.covers?(2, 6)
    refute ship.covers?(3, 2)

  end

如果我在 ship.covers 上做 binding.pry？使用这些参数中的任何一个，我都会得到正确的答案。由于某种原因，测试仍然无法通过...

这是错误信息。信息不多...

1) Failure:
BattleshipTest#test_09_ship_can_be_placed_down [battleship_minitest.rb:73]:
Failed assertion, no message given.

Binding.pry 测试通过

[1] pry(main)> ship1.covers?(2, 1)
=> true
[2] pry(main)> ship1.covers?(3, 1)
=> true
[3] pry(main)> ship1.covers?(4, 1)
=> true
[4] pry(main)> ship1.covers?(5, 1)
=> true
[5] pry(main)> ship1.covers?(1, 1)
=> false
[6] pry(main)> ship1.covers?(6, 1)
=> false
[7] pry(main)> ship1.covers?(4, 2)
=> false

Binding.pry 对于失败的测试

[1] pry(main)> ship2.covers?(2, 1)
=> false
[2] pry(main)> ship2.covers?(2, 2)
=> true
[3] pry(main)> ship2.covers?(2, 3)
=> true
[4] pry(main)> ship2.covers?(2, 4)
=> true
[5] pry(main)> ship2.covers?(2, 5)
=> true
[6] pry(main)> ship2.covers?(2, 6)
=> false
[7] pry(main)> ship2.covers?(3, 2)
=> false

Answer 1

你在断言一个备考方法（我的想法）：

assert ship.place(2, 1, false)

ship.place returns 轴的值，因为它是在方法中最后分配的。它适用于第一种情况，因为 axis 设置为 true。

Minitest 不会通过，尽管使用 binding.pry 检查标准是正确的

Minitest won't pass, although criteria are correct when checked with binding.pry

ruby

assertions

minitest

这是被测试的对象

这个测试会通过

这是不会通过的测试

这是错误信息。信息不多...

Binding.pry 测试通过

Binding.pry 对于失败的测试