Rename `Ci::Stage` class to `Ci::LegacyStage`

app/models/ci/stage.rb → app/models/ci/legacy_stage.rb

 module Ci
   # Currently this is artificial object, constructed dynamically
   # We should migrate this object to actual database record in the future
-  class Stage
+  class LegacyStage
     include StaticModel
 
     attr_reader :pipeline, :name

app/models/ci/pipeline.rb

@@ -161,7 +161,7 @@ module Ci
     end
 
     def legacy_stage(name)
-      stage = Ci::Stage.new(self, name: name)
+      stage = Ci::LegacyStage.new(self, name: name)
       stage unless stage.statuses_count.zero?
     end
 
@@ -180,7 +180,7 @@ module Ci
         .pluck('sg.stage', status_sql, "(#{warnings_sql})")
 
       stages_with_statuses.map do |stage|
-        Ci::Stage.new(self, Hash[%i[name status warnings].zip(stage)])
+        Ci::LegacyStage.new(self, Hash[%i[name status warnings].zip(stage)])
       end
     end
 

spec/factories/ci/stages.rb

 FactoryGirl.define do
-  factory :ci_stage, class: Ci::Stage do
+  factory :ci_stage, class: Ci::LegacyStage do
     transient do
       name 'test'
       status nil
@@ -8,7 +8,9 @@ FactoryGirl.define do
     end
 
     initialize_with do
-      Ci::Stage.new(pipeline, name: name, status: status, warnings: warnings)
+      Ci::LegacyStage.new(pipeline, name: name,
+                                    status: status,
+                                    warnings: warnings)
     end
   end
 end

spec/models/ci/stage_spec.rb → spec/models/ci/legacy_stage_spec.rb

 require 'spec_helper'
 
-describe Ci::Stage, models: true do
+describe Ci::LegacyStage, :models do
   let(:stage) { build(:ci_stage) }
   let(:pipeline) { stage.pipeline }
   let(:stage_name) { stage.name }

spec/models/ci/pipeline_spec.rb

@@ -292,7 +292,7 @@ describe Ci::Pipeline, models: true do
         create(:commit_status, pipeline: pipeline, stage: 'test')
       end
 
-      it { expect(subject).to be_a Ci::Stage }
+      it { expect(subject).to be_a Ci::LegacyStage }
       it { expect(subject.name).to eq 'test' }
       it { expect(subject.statuses).not_to be_empty }
     end