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A Rails plugin to create tests for you when your app throws an unhandled exception
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Laziness does one thing: if your application throws an unhandled error, it will automatically create a failing test for you to copy into the appropriate test file - or if you're using RSpec, it'll write the appropriate spec for you.


If you're running ExceptionNotifier, you'll need to make sure that vendor/plugins/laziness/views/_laziness.rhtml is copied into vendor/plugins/exception_notification/views/exception_notifier - that will allow your exception notifier emails to include the generated test (or spec). The file is normally copied over by the plugin installation process, but if it doesn't make it there you can move it by hand.


Say you're browsing your site and you get a 500 error on /users/new, which is rendering the UsersController#new action. In the error page (or exception email, if you're using ExceptionNotifier), Laziness adds something like the following:

def test_get_users_new_should_not_raise_nameerror_exception
  assert_nothing_raised(NameError) do
    get :new, {[params from request]}, {[session from request]}, {[flash from request]}

The exact exception asserted (in this case, NameError) will depend on what caused the 500 error in the first place.

If you're using RSpec, the generated code will look like this:

describe "Handling GET users new" do
  it "should not raise NameError" do
    lambda { 
      get :new, {[params from request]}, {[session from request]}, {[flash from request]}
    }.should_not raise_error(NameError)

Catching Specific Exceptions

You can customize the tests to be generated on an exception-by-exception basis; just add the appropriate file to lib/exceptions/what/ever.rb and make sure it defines ++test++ and ++spec++ methods; look at lib/exceptions/action_controller/unknown_view.rb for an example.

Copyright (c) 2008 Ben Scofield, released under the MIT license
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