Add specs for methods that count pipeline seeds size

spec/lib/gitlab/ci/stage/seed_spec.rb

@@ -11,6 +11,12 @@ describe Gitlab::Ci::Stage::Seed do
     described_class.new(pipeline, 'test', builds)
   end
 
+  describe '#size' do
+    it 'returns a number of jobs in the stage' do
+      expect(subject.size).to eq 2
+    end
+  end
+
   describe '#stage' do
     it 'returns hash attributes of a stage' do
       expect(subject.stage).to be_a Hash

spec/models/ci/pipeline_spec.rb

@@ -242,7 +242,7 @@ describe Ci::Pipeline, :mailer do
 
     describe '#stage_seeds' do
       let(:pipeline) do
-        create(:ci_pipeline, config: { rspec: { script: 'rake' } })
+        build(:ci_pipeline, config: { rspec: { script: 'rake' } })
       end
 
       it 'returns preseeded stage seeds object' do
@@ -251,6 +251,14 @@ describe Ci::Pipeline, :mailer do
       end
     end
 
+    describe '#seeds_size' do
+      let(:pipeline) { build(:ci_pipeline_with_one_job) }
+
+      it 'returns number of jobs in stage seeds' do
+        expect(pipeline.seeds_size).to eq 1
+      end
+    end
+
     describe '#legacy_stages' do
       subject { pipeline.legacy_stages }