Reduce stage seeds coupling between pipeline and YAML

This is a first step to decouple pipeline from YAML processing. It
reduces the coupling by removing some methods that introduce coupling
and by moving logic into separate chain element that is being used to
populate pipelines with stages and builds.

2 files changed, 26 insertions, 22 deletions

diff --git a/spec/lib/gitlab/ci/pipeline/chain/populate_spec.rb b/spec/lib/gitlab/ci/pipeline/chain/populate_spec.rb
index f1fc7acb969..115c76aff2d 100644
--- a/spec/lib/gitlab/ci/pipeline/chain/populate_spec.rb
+++ b/spec/lib/gitlab/ci/pipeline/chain/populate_spec.rb
@@ -42,6 +42,32 @@ describe Gitlab::Ci::Pipeline::Chain::Populate do
     end
   end
 
+  context 'when pipeline is empty' do
+    let(:config) do
+      { rspec: {
+          script: 'ls',
+          only: ['something']
+      } }
+    end
+
+    let(:pipeline) do
+      build(:ci_pipeline, project: project, config: config)
+    end
+
+    before do
+      step.perform!
+    end
+
+    it 'breaks the chain' do
+      expect(step.break?).to be true
+    end
+
+    it 'appends an error about missing stages' do
+      expect(pipeline.errors.to_a)
+        .to include 'No stages / jobs for this pipeline.'
+    end
+  end
+
   context 'when pipeline has validation errors' do
     let(:pipeline) do
       build(:ci_pipeline, project: project, ref: nil)
diff --git a/spec/lib/gitlab/ci/pipeline/chain/validate/config_spec.rb b/spec/lib/gitlab/ci/pipeline/chain/validate/config_spec.rb
index 5c12c6e6392..c53294d091c 100644
--- a/spec/lib/gitlab/ci/pipeline/chain/validate/config_spec.rb
+++ b/spec/lib/gitlab/ci/pipeline/chain/validate/config_spec.rb
@@ -76,28 +76,6 @@ describe Gitlab::Ci::Pipeline::Chain::Validate::Config do
     end
   end
 
-  context 'when pipeline has no stages / jobs' do
-    let(:config) do
-      { rspec: {
-          script: 'ls',
-          only: ['something']
-      } }
-    end
-
-    let(:pipeline) do
-      build(:ci_pipeline, project: project, config: config)
-    end
-
-    it 'appends an error about missing stages' do
-      expect(pipeline.errors.to_a)
-        .to include 'No stages / jobs for this pipeline.'
-    end
-
-    it 'breaks the chain' do
-      expect(step.break?).to be true
-    end
-  end
-
   context 'when pipeline contains configuration validation errors' do
     let(:config) { { rspec: {} } }