Ruby-on-rails Rails RSpec 测试 has_many :through 关系
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/3973745/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
Rails RSpec Tests for a has_many :through Relationship
提问by Mario Zigliotto
I'm new to testing and rails but i'm trying to get my TDD process down properly.
我是测试和 Rails 的新手，但我正在尝试正确地关闭我的 TDD 过程。
I was wondering if you use any sort of paradigm for testing has_many :through relationships? (or just has_many in general i suppose).
我想知道您是否使用任何类型的范例来测试 has_many :through 关系？（或者我想一般只是 has_many ）。
For example, i find that in my model specs i'm definitely writing simple tests to check both ends of a relationship for relating methods.
例如，我发现在我的模型规范中，我肯定是在编写简单的测试来检查关系的两端是否有相关方法。
ie:
IE：
require 'spec_helper'
describe Post do
before(:each) do
@attr = { :subject => "f00 Post Subject", :content => "8ar Post Body Content" }
end
describe "validations" do
...
end
describe "categorized posts" do
before(:each) do
@post = Post.create!(@attr)
end
it "should have a categories method" do
@post.should respond_to(:categories)
end
end
end
Then in my categories spec i do the inverse test and check for @category.posts
然后在我的类别规范中，我进行反向测试并检查 @category.posts
What else am i missing? thanks!!
我还缺少什么？谢谢！！
采纳答案by randmin
For the sake of completeness, in 2020 this is possible without additional gems.
为完整起见，2020 年无需额外宝石即可实现。
it "has many categories" do
should respond_to(:categories)
end
And even more explicit:
甚至更明确：
it "belongs to category" do
t = Post.reflect_on_association(:category)
expect(t.macro).to eq(:belongs_to)
end
(see Ruby API on Reflection)
The second example makes sure that a "has_one" is not confused with a "belongs_to" and vice versa
第二个示例确保“has_one”不会与“belongs_to”混淆，反之亦然
It is, however, not limited to has_many :through relationships, but can be used for any association applied to the model.
但是，它不限于 has_many :through 关系，还可以用于应用于模型的任何关联。
(Note: This is using the new rspec 2.11 syntaxwith Rails 5.2.4)
（注意：这是在Rails 5.2.4 中使用新的 rspec 2.11 语法）
回答by Peter Brown
I would recommend checking out a gem called Shoulda. It has a lot of macros for testing things like relationships and validations.
我建议您查看一个名为Shoulda的宝石。它有很多用于测试关系和验证等内容的宏。
If all you want is to test that the has_many relationship exists, then you could do the following:
如果您只想测试 has_many 关系是否存在，那么您可以执行以下操作：
describe Post do
it { should have_many(:categories) }
end
Or if you're testing a has_many :through, then you'd use this:
或者，如果您正在测试 has_many :through，那么您可以使用它：
describe Post do
it { should have_many(:categories).through(:other_model) }
end
I find the Shoulda Rdocpage very helpful too.
我发现Shoulda Rdoc页面也很有帮助。
回答by GregC
describe "when Book.new is called" do
before(:each) do
@book = Book.new
end
#otm
it "should be ok with an associated publisher" do
@book.publisher = Publisher.new
@book.should have(:no).errors_on(:publisher)
end
it "should have an associated publisher" do
@book.should have_at_least(1).error_on(:publisher)
end
#mtm
it "should be ok with at least one associated author" do
@book.authors.build
@book.should have(:no).errors_on(:authors)
end
it "should have at least one associated author" do
@book.should have_at_least(1).error_on(:authors)
end
end
回答by Wayne Conrad
remarkablewill do this nicely:
非凡将很好地做到这一点：
describe Pricing do
should_have_many :accounts, :through => :account_pricings
should_have_many :account_pricings
should_have_many :job_profiles, :through => :job_profile_pricings
should_have_many :job_profile_pricings
end
Generally, you just copy all of your relationships from the model to the spec and change "has" to "should_have", "belongs_to" to "should_belong_to", and so on. To answer the charge that it's testing rails, it checks the database also, making sure that the association works.
通常，您只需将模型中的所有关系复制到规范中，然后将“has”更改为“should_have”，将“belongs_to”更改为“should_belong_to”，依此类推。为了回答它正在测试 Rails 的指控，它还检查数据库，确保关联有效。
Macros are also included for checking validations as well:
还包括用于检查验证的宏：
should_validate_numericality_of :amount, :greater_than_or_equal_to => 0
