We're in Rails 4.2 so we can remove it. This gets rid of the following
message when running tests:
```
DEPRECATION WARNING: Suppressing Selenium deprecation warnings is not needed any more. (called from block in <top (required)> at /usr/src/app/spec/spec_helper.rb:214)
```
Devise has been complaining about this for a while in the test suite:
```
[Devise] including `Devise::TestHelpers` is deprecated and will be removed from Devise.
For controller tests, please include `Devise::Test::ControllerHelpers` instead.
```
In v5 the default value is true, that means that all parent objects (for example the order od a line item) will be built using the same strategy as the object (build or create), in v4 and now with this config, the parent is always created
We can revert this and use the default value but that will require some adaptions, quite a lot of specs are broken with that behaviour activated
Apparently, although we tend to add the type of spec file some RSpec
methods are not working without it. We're getting:
```
NoMethodError:
undefined method `helper' for RSpec::ExampleGroups::SpreeSharedOrderDetailsHtmlHaml:Class
```
```
NameError:
undefined local variable or method `controller' for #<RSpec::ExampleGroups::SpreeAdminUsersController::AuthorizeAdmin:0x00007fa8b32addf8>
# ./spec/controllers/spree/admin/users_controller_spec.rb:10:in `block (3 levels) in <top (required)>'
```
It needs more investigation but another day.
When two people tried to buy the same item at the same time, it was
possible to oversell the item and end up with negative stock.
Parallel checkouts could also lead to other random failures. This spec
is testing that scenario by starting two threads which would run into a
race condition unless they use effective synchronisation. The added spec
fails if the synchronisation is removed from the CheckoutController.
It turns out that we were executing `DatabaseCleaner.clean` on two
`after(:each)` blocks. One for all specs and another one for `js: true`
specs. As a result feature specs were hitting both which slows them down
considerably.
On my machine this changes consistently saves 2sec on
`spec/features/consumer/shops_spec.rb` but chances are it has an
accumulative effect when run on the whole test suite.
