A quickie for my own remembrance. I'm currently setting up HttpMock to test ActiveResource. I'd set up a few extra "routes" for it to mock out and kept getting the error below:
NoMethodError: undefined method `size' for :not_found: Symbol
For the code line:
mock.get "/users/#{uid}.xml", {}, :not_found
The fix was pretty simple - I'd just accidentally missed out the "nil" for the body - ie it

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