How to test carrierwave version size with Rspec - ruby-on-rails-3

Question

I have a CarrierWave::Uploader that produces three version of the uploaded image.
# Process files as they are uploaded:
process :resize_to_fit => [400, 400]
# Create different versions of your uploaded files:
version :thumb do
process :resize_to_fit => [60, 60]
end
version :small do
process :resize_to_fit => [24, 24]
end
And in my tests I try to verify the dimensions of the generated images
require 'spec_helper'
require 'carrierwave/test/matchers'
describe 'manufacturer logo uploader' do
include CarrierWave::Test::Matchers
before(:each) do
image_path = Rails.root.join('test/fixtures/images', 'avatar100.gif').to_s
#manufacturer = Factory.create(:manufacturer, :page_status => 1)
#manufacturer.logo_image = File.open(image_path)
#manufacturer.save!
end
context "manufacturer logo dimensions" do
it "should have three versions" do
#manufacturer.logo_image.should have_dimensions(400,400)
#manufacturer.logo_image.thumb.should have_dimensions(60,60)
#manufacturer.logo_image.small.should have_dimensions(24,24)
end
end
end
but this test depends on the actual image and resize_to_fit will not necessarily resize it to the specified dimensions. Any ideas on how to test this using stubs?

Answer 1

Here's my solution, which actually processes an image. This is slower than stubs, but verifies the actual resize (as long as the input image is larger than the target size).
describe 'images' do
include CarrierWave::Test::Matchers
before do
MyUploader.enable_processing = true
end
it 'are resized' do
path = Rails.root.join *%w[ spec data sample.png ]
my_model = FactoryGirl.create :my_model, image: path.open
my_model.artwork.small.should be_no_larger_than(300, 400)
end
after do
MyUploader.enable_processing = false
end
end

Answer 2

long shot but can you try to add this
before do
DocumentUploader.enable_processing = true
end
because processing (current version and other versions) could be turned off by default for performance reason
had similar problem related to process set_file_name_to_model that was doing something setting "file_name" on model attribute
http://ruby-on-rails-eq8.blogspot.co.uk/2015/03/carrierwave-uploader-not-triggering.html