rspec shoulda matchers 预计属于多态

Question

我正在尝试测试我的多态关联，但我似乎无法让它通过

模型：

class Foo < ApplicationRecord
  belongs_to :bar, polymorphic: true, optional: true
end

现在我的测试看起来像

RSpec.describe Foo, type: :model do
  subject { build(:foo) }
  it { is_expected.to belong_to(:bar) }
end

我收到的错误

Foo
  is expected to belong to bar required: true (FAILED - 1)

Failures:

>   1) Foo is expected to belong to bar required: true
>      Failure/Error: it { is_expected.to belong_to(:bar) }
>        Expected Foo to have a belongs_to association called bar (and for the record to fail validation if :bar is unset; i.e., either the
> association should have been defined with `required: true`, or there
> should be a presence validation on :bar)
>      /# ./spec/models/foo_spec.rb:4:in `block (2 levels) in <top (required)>'

现在这个关联可以是零值

Answer 1

问题似乎是：

如果 :bar 未设置，则记录验证失败；

因为，你有optional: true——这部分不满意。

看起来应该假设应该需要一个关系，除非你另有说明。

尝试像这样修改这个匹配器

it { is_expected.to belong_to(:bar).optional }

https://github.com/thoughtbot/shoulda-matchers/blob/master/lib/shoulda/matchers/active_record/association_matcher.rb#L304:L321