How to rspec mock open-uri?

问题

I have this simple code where I am sending http request and reading all the response. Here is my rails code

open("http://stackoverflow.com/questions/ask")

How can I write spec for this line of code. I dont have the option to use mocha and webmock. I can only use mocking framework of Rpsec.

I have tried to use this statement

OpenURI.stub!(:open_uri).should_receive(:open).with("http://stackoverflow.com/questions/ask")

but i keep getting this error

RSpec::Mocks::MockExpectationError: (#<RSpec::Mocks::MessageExpectation:0xd1a7914>).open("http://stackoverflow.com/questions/ask")
expected: 1 time
received: 0 times

回答1:

I thought that the open method is defined on the level of the Kernel, but I was wrong.

If you would like to mock the open, you should do it on the level of your object like this:

it "should do something" do
  object_under_test = ObjectUnderTest.new
  object_under_test.should_receive(:open).with("http://example.org")
end

回答2:

I did:

my_object.stub_chain(:open, :read) { "my return value" }

回答3:

According to this link http://distillations.2rye.com/2011/08/mock-the-web-openuri/ the open function is defined on the Kernel module, but mixed into your controller. Therefore you need to stub the call at that level. This solution works well for RSpec controller tests:

  html_content = <<-EOS
          <html><head>
           <title>Some Title</title>
          </head>
          <body>Some Content</body></html>
        EOS

  YourController.any_instance.stub(:open).and_return html_content

回答4:

To stub open-uri you can use this syntax RSpec 3+

file = double('file')
expect(OpenURI).to receive(:open_uri).and_return(file)

来源：https://stackoverflow.com/questions/10796986/how-to-rspec-mock-open-uri

标签

rspec-rails