Use nice matcher for sidekiq job enqueues

spec/controllers/api/asciicasts_controller_spec.rb

@@ -17,7 +17,8 @@ describe Api::AsciicastsController do
       end
 
       it 'enqueues snapshot capture' do
-        expect { post :create }.to change(SnapshotWorker.jobs, :size).by(1)
+        post :create
+        SnapshotWorker.should have_queued_job(asciicast.id)
       end
 
       it 'returns status 201' do

spec/support/sidekiq_matchers.rb

@@ -0,0 +1,17 @@
+RSpec::Matchers.define :have_queued_job do |*expected|
+  match do |actual|
+    actual.jobs.any? { |job| Array(expected) == job["args"] }
+  end
+
+  failure_message_for_should do |actual|
+    "expected that #{actual} would have a job queued with #{expected}"
+  end
+
+  failure_message_for_should_not do |actual|
+    "expected that #{actual} would not a have a job queued with #{expected}"
+  end
+
+  description do
+    "have a job queued with #{expected}"
+  end
+end