RSpec how to stub open?

Question

I've been trying to stub open, the open-uri version, and I'm not succeeding.

I've tried doing the following but the request keeps going through:

Kernel.should_receive(:open).and_return("Whatever for now")

I've also tried to do

OpenURI::OpenRead.should_receive(:open).and_return("Whatever for now")

Since I tracked down that was where HTTP requests were made in OpenURI.

Thanks in advance for any suggestions!

Answer 1

Here is what I do

class Gateway

  def do_something
    open('http://example.com').read
  end

end

In my spec i do the following:

describe 'communication' do

  it 'should receive valid response from example.com' do
    gateway = Gateway.new
    gateway.stub_chain(:open, :read).and_return('Remote server response')

    gateway.do_something.should == "Remote server response"
  end 

end

Answer 2

I found a solution here on Stack Overflow after some more time on Google (I can't believe I didn't find this before).

Explanation taken from here and written by Tony Pitluga (not linkable).

If you are calling sleep within the context of an object, you should stub it on the object[...]
The key is, to stub sleep on whatever "self" is in the context where sleep is called.

So I did this and it all worked out:

let(:read) { mock('open') }

it "should return the new log-level when the log level was set successfully" do
    read.stub(:read).and_return('log-level set to 1')
    kannel.should_receive(:open).and_return(read)

    kannel.set_log_level(1).should == 1
  end