Merge branch 'backstage/gb/populating-pipeline-refactoring' into 'master'

Improve how we populate pipeline with stages and builds

Closes #43941

See merge request gitlab-org/gitlab-ce!17841

21 files changed, 1151 insertions, 892 deletions

diff --git a/app/models/ci/pipeline.rb b/app/models/ci/pipeline.rb
index 44f9bdf111e..434b9b64c65 100644
--- a/app/models/ci/pipeline.rb
+++ b/app/models/ci/pipeline.rb
@@ -6,6 +6,7 @@ module Ci
     include AfterCommitQueue
     include Presentable
     include Gitlab::OptimisticLocking
+    include Gitlab::Utils::StrongMemoize
 
     belongs_to :project, inverse_of: :pipelines
     belongs_to :user
@@ -361,21 +362,23 @@ module Ci
     def stage_seeds
       return [] unless config_processor
 
-      @stage_seeds ||= config_processor.stage_seeds(self)
+      strong_memoize(:stage_seeds) do
+        seeds = config_processor.stages_attributes.map do |attributes|
+          Gitlab::Ci::Pipeline::Seed::Stage.new(self, attributes)
+        end
+
+        seeds.select(&:included?)
+      end
     end
 
     def seeds_size
-      @seeds_size ||= stage_seeds.sum(&:size)
+      stage_seeds.sum(&:size)
     end
 
     def has_kubernetes_active?
       project.deployment_platform&.active?
     end
 
-    def has_stage_seeds?
-      stage_seeds.any?
-    end
-
     def has_warnings?
       builds.latest.failed_but_allowed.any?
     end
@@ -388,6 +391,9 @@ module Ci
       end
     end
 
+    ##
+    # TODO, setting yaml_errors should be moved to the pipeline creation chain.
+    #
     def config_processor
       return unless ci_yaml_file
       return @config_processor if defined?(@config_processor)
@@ -472,6 +478,14 @@ module Ci
       end
     end
 
+    def protected_ref?
+      strong_memoize(:protected_ref) { project.protected_for?(ref) }
+    end
+
+    def legacy_trigger
+      strong_memoize(:legacy_trigger) { trigger_requests.first }
+    end
+
     def predefined_variables
       Gitlab::Ci::Variables::Collection.new
         .append(key: 'CI_PIPELINE_ID', value: id.to_s)
diff --git a/app/services/ci/create_pipeline_service.rb b/app/services/ci/create_pipeline_service.rb
index ad27f320853..6ce86983287 100644
--- a/app/services/ci/create_pipeline_service.rb
+++ b/app/services/ci/create_pipeline_service.rb
@@ -7,6 +7,7 @@ module Ci
                 Gitlab::Ci::Pipeline::Chain::Validate::Repository,
                 Gitlab::Ci::Pipeline::Chain::Validate::Config,
                 Gitlab::Ci::Pipeline::Chain::Skip,
+                Gitlab::Ci::Pipeline::Chain::Populate,
                 Gitlab::Ci::Pipeline::Chain::Create].freeze
 
     def execute(source, ignore_skip_ci: false, save_on_errors: true, trigger_request: nil, schedule: nil, &block)
diff --git a/app/services/ci/create_pipeline_stages_service.rb b/app/services/ci/create_pipeline_stages_service.rb
deleted file mode 100644
index f2c175adee6..00000000000
--- a/app/services/ci/create_pipeline_stages_service.rb
+++ /dev/null
@@ -1,20 +0,0 @@
-module Ci
-  class CreatePipelineStagesService < BaseService
-    def execute(pipeline)
-      pipeline.stage_seeds.each do |seed|
-        seed.user = current_user
-
-        seed.create! do |build|
-          ##
-          # Create the environment before the build starts. This sets its slug and
-          # makes it available as an environment variable
-          #
-          if build.has_environment?
-            environment_name = build.expanded_environment_name
-            project.environments.find_or_create_by(name: environment_name)
-          end
-        end
-      end
-    end
-  end
-end
diff --git a/app/services/ci/pipeline_trigger_service.rb b/app/services/ci/pipeline_trigger_service.rb
index a9813d774bb..85533a1cbdb 100644
--- a/app/services/ci/pipeline_trigger_service.rb
+++ b/app/services/ci/pipeline_trigger_service.rb
@@ -16,8 +16,8 @@ module Ci
 
       pipeline = Ci::CreatePipelineService.new(project, trigger.owner, ref: params[:ref])
         .execute(:trigger, ignore_skip_ci: true) do |pipeline|
-          pipeline.trigger_requests.create!(trigger: trigger)
-          create_pipeline_variables!(pipeline)
+          pipeline.trigger_requests.build(trigger: trigger)
+          pipeline.variables.build(variables)
         end
 
       if pipeline.persisted?
@@ -33,14 +33,10 @@ module Ci
       end
     end
 
-    def create_pipeline_variables!(pipeline)
-      return unless params[:variables]
-
-      variables = params[:variables].map do |key, value|
+    def variables
+      params[:variables].to_h.map do |key, value|
         { key: key, value: value }
       end
-
-      pipeline.variables.create!(variables)
     end
   end
 end
diff --git a/lib/gitlab/ci/pipeline/chain/create.rb b/lib/gitlab/ci/pipeline/chain/create.rb
index d5e17a123df..f4c8d5342c1 100644
--- a/lib/gitlab/ci/pipeline/chain/create.rb
+++ b/lib/gitlab/ci/pipeline/chain/create.rb
@@ -9,11 +9,16 @@ module Gitlab
             ::Ci::Pipeline.transaction do
               pipeline.save!
 
-              @command.seeds_block&.call(pipeline)
-
-              ::Ci::CreatePipelineStagesService
-                .new(project, current_user)
-                .execute(pipeline)
+              ##
+              # Create environments before the pipeline starts.
+              #
+              pipeline.builds.each do |build|
+                if build.has_environment?
+                  project.environments.find_or_create_by(
+                    name: build.expanded_environment_name
+                  )
+                end
+              end
             end
           rescue ActiveRecord::RecordInvalid => e
             error("Failed to persist the pipeline: #{e}")
diff --git a/lib/gitlab/ci/pipeline/chain/populate.rb b/lib/gitlab/ci/pipeline/chain/populate.rb
new file mode 100644
index 00000000000..b2b00c8cb4b
--- /dev/null
+++ b/lib/gitlab/ci/pipeline/chain/populate.rb
@@ -0,0 +1,47 @@
+module Gitlab
+  module Ci
+    module Pipeline
+      module Chain
+        class Populate < Chain::Base
+          include Chain::Helpers
+
+          PopulateError = Class.new(StandardError)
+
+          def perform!
+            ##
+            # Populate pipeline with block argument of CreatePipelineService#execute.
+            #
+            @command.seeds_block&.call(pipeline)
+
+            ##
+            # Populate pipeline with all stages and builds from pipeline seeds.
+            #
+            pipeline.stage_seeds.each do |stage|
+              stage.user = current_user
+
+              pipeline.stages << stage.to_resource
+
+              stage.seeds.each do |build|
+                pipeline.builds << build.to_resource
+              end
+            end
+
+            if pipeline.stages.none?
+              return error('No stages / jobs for this pipeline.')
+            end
+
+            if pipeline.invalid?
+              return error('Failed to build the pipeline!')
+            end
+
+            raise Populate::PopulateError if pipeline.persisted?
+          end
+
+          def break?
+            pipeline.errors.any?
+          end
+        end
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/ci/pipeline/chain/validate/config.rb b/lib/gitlab/ci/pipeline/chain/validate/config.rb
index 075504bcce5..a3bd2a5a23a 100644
--- a/lib/gitlab/ci/pipeline/chain/validate/config.rb
+++ b/lib/gitlab/ci/pipeline/chain/validate/config.rb
@@ -16,11 +16,7 @@ module Gitlab
                   @pipeline.drop!(:config_error)
                 end
 
-                return error(@pipeline.yaml_errors)
-              end
-
-              unless @pipeline.has_stage_seeds?
-                return error('No stages / jobs for this pipeline.')
+                error(@pipeline.yaml_errors)
               end
             end
 
diff --git a/lib/gitlab/ci/pipeline/seed/base.rb b/lib/gitlab/ci/pipeline/seed/base.rb
new file mode 100644
index 00000000000..db9706924bb
--- /dev/null
+++ b/lib/gitlab/ci/pipeline/seed/base.rb
@@ -0,0 +1,21 @@
+module Gitlab
+  module Ci
+    module Pipeline
+      module Seed
+        class Base
+          def attributes
+            raise NotImplementedError
+          end
+
+          def included?
+            raise NotImplementedError
+          end
+
+          def to_resource
+            raise NotImplementedError
+          end
+        end
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/ci/pipeline/seed/build.rb b/lib/gitlab/ci/pipeline/seed/build.rb
new file mode 100644
index 00000000000..7cd7c864448
--- /dev/null
+++ b/lib/gitlab/ci/pipeline/seed/build.rb
@@ -0,0 +1,52 @@
+module Gitlab
+  module Ci
+    module Pipeline
+      module Seed
+        class Build < Seed::Base
+          include Gitlab::Utils::StrongMemoize
+
+          delegate :dig, to: :@attributes
+
+          def initialize(pipeline, attributes)
+            @pipeline = pipeline
+            @attributes = attributes
+
+            @only = attributes.delete(:only)
+            @except = attributes.delete(:except)
+          end
+
+          def user=(current_user)
+            @attributes.merge!(user: current_user)
+          end
+
+          def included?
+            strong_memoize(:inclusion) do
+              only_specs = Gitlab::Ci::Build::Policy.fabricate(@only)
+              except_specs = Gitlab::Ci::Build::Policy.fabricate(@except)
+
+              only_specs.all? { |spec| spec.satisfied_by?(@pipeline) } &&
+                except_specs.none? { |spec| spec.satisfied_by?(@pipeline) }
+            end
+          end
+
+          def attributes
+            @attributes.merge(
+              pipeline: @pipeline,
+              project: @pipeline.project,
+              ref: @pipeline.ref,
+              tag: @pipeline.tag,
+              trigger_request: @pipeline.legacy_trigger,
+              protected: @pipeline.protected_ref?
+            )
+          end
+
+          def to_resource
+            strong_memoize(:resource) do
+              ::Ci::Build.new(attributes)
+            end
+          end
+        end
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/ci/pipeline/seed/stage.rb b/lib/gitlab/ci/pipeline/seed/stage.rb
new file mode 100644
index 00000000000..1fcbdc1b15a
--- /dev/null
+++ b/lib/gitlab/ci/pipeline/seed/stage.rb
@@ -0,0 +1,51 @@
+module Gitlab
+  module Ci
+    module Pipeline
+      module Seed
+        class Stage < Seed::Base
+          include Gitlab::Utils::StrongMemoize
+
+          delegate :size, to: :seeds
+          delegate :dig, to: :seeds
+
+          def initialize(pipeline, attributes)
+            @pipeline = pipeline
+            @attributes = attributes
+
+            @builds = attributes.fetch(:builds).map do |attributes|
+              Seed::Build.new(@pipeline, attributes)
+            end
+          end
+
+          def user=(current_user)
+            @builds.each { |seed| seed.user = current_user }
+          end
+
+          def attributes
+            { name: @attributes.fetch(:name),
+              pipeline: @pipeline,
+              project: @pipeline.project }
+          end
+
+          def seeds
+            strong_memoize(:seeds) do
+              @builds.select(&:included?)
+            end
+          end
+
+          def included?
+            seeds.any?
+          end
+
+          def to_resource
+            strong_memoize(:stage) do
+              ::Ci::Stage.new(attributes).tap do |stage|
+                seeds.each { |seed| stage.builds << seed.to_resource }
+              end
+            end
+          end
+        end
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/ci/stage/seed.rb b/lib/gitlab/ci/stage/seed.rb
deleted file mode 100644
index f33c87f554d..00000000000
--- a/lib/gitlab/ci/stage/seed.rb
+++ /dev/null
@@ -1,62 +0,0 @@
-module Gitlab
-  module Ci
-    module Stage
-      class Seed
-        include ::Gitlab::Utils::StrongMemoize
-
-        attr_reader :pipeline
-
-        delegate :project, to: :pipeline
-        delegate :size, to: :@jobs
-
-        def initialize(pipeline, stage, jobs)
-          @pipeline = pipeline
-          @stage = { name: stage }
-          @jobs = jobs.to_a.dup
-        end
-
-        def user=(current_user)
-          @jobs.map! do |attributes|
-            attributes.merge(user: current_user)
-          end
-        end
-
-        def stage
-          @stage.merge(project: project)
-        end
-
-        def builds
-          trigger = pipeline.trigger_requests.first
-
-          @jobs.map do |attributes|
-            attributes.merge(project: project,
-                             ref: pipeline.ref,
-                             tag: pipeline.tag,
-                             trigger_request: trigger,
-                             protected: protected_ref?)
-          end
-        end
-
-        def create!
-          pipeline.stages.create!(stage).tap do |stage|
-            builds_attributes = builds.map do |attributes|
-              attributes.merge(stage_id: stage.id)
-            end
-
-            pipeline.builds.create!(builds_attributes).each do |build|
-              yield build if block_given?
-            end
-          end
-        end
-
-        private
-
-        def protected_ref?
-          strong_memoize(:protected_ref) do
-            project.protected_for?(pipeline.ref)
-          end
-        end
-      end
-    end
-  end
-end
diff --git a/lib/gitlab/ci/yaml_processor.rb b/lib/gitlab/ci/yaml_processor.rb
index a7285ac8f9d..bc2a6f98dae 100644
--- a/lib/gitlab/ci/yaml_processor.rb
+++ b/lib/gitlab/ci/yaml_processor.rb
@@ -27,7 +27,7 @@ module Gitlab
       end
 
       def build_attributes(name)
-        job = @jobs[name.to_sym] || {}
+        job = @jobs.fetch(name.to_sym, {})
 
         { stage_idx: @stages.index(job[:stage]),
           stage: job[:stage],
@@ -53,30 +53,24 @@ module Gitlab
           }.compact }
       end
 
-      def pipeline_stage_builds(stage, pipeline)
-        selected_jobs = @jobs.select do |_, job|
-          next unless job[:stage] == stage
-
-          only_specs = Gitlab::Ci::Build::Policy
-            .fabricate(job.fetch(:only, {}))
-          except_specs = Gitlab::Ci::Build::Policy
-            .fabricate(job.fetch(:except, {}))
-
-          only_specs.all? { |spec| spec.satisfied_by?(pipeline) } &&
-            except_specs.none? { |spec| spec.satisfied_by?(pipeline) }
-        end
-
-        selected_jobs.map { |_, job| build_attributes(job[:name]) }
+      def stage_builds_attributes(stage)
+        @jobs.values
+          .select { |job| job[:stage] == stage }
+          .map { |job| build_attributes(job[:name]) }
       end
 
-      def stage_seeds(pipeline)
-        seeds = @stages.uniq.map do |stage|
-          builds = pipeline_stage_builds(stage, pipeline)
+      def stages_attributes
+        @stages.uniq.map do |stage|
+          seeds = stage_builds_attributes(stage).map do |attributes|
+            job = @jobs.fetch(attributes[:name].to_sym)
 
-          Gitlab::Ci::Stage::Seed.new(pipeline, stage, builds) if builds.any?
-        end
+            attributes
+              .merge(only: job.fetch(:only, {}))
+              .merge(except: job.fetch(:except, {}))
+          end
 
-        seeds.compact
+          { name: stage, index: @stages.index(stage), builds: seeds }
+        end
       end
 
       def self.validation_message(content)
diff --git a/spec/lib/gitlab/ci/pipeline/chain/create_spec.rb b/spec/lib/gitlab/ci/pipeline/chain/create_spec.rb
index 1b03227d67b..dc12ba076bc 100644
--- a/spec/lib/gitlab/ci/pipeline/chain/create_spec.rb
+++ b/spec/lib/gitlab/ci/pipeline/chain/create_spec.rb
@@ -5,23 +5,23 @@ describe Gitlab::Ci::Pipeline::Chain::Create do
   set(:user) { create(:user) }
 
   let(:pipeline) do
-    build(:ci_pipeline_with_one_job, project: project,
-                                     ref: 'master')
+    build(:ci_empty_pipeline, project: project, ref: 'master')
   end
 
   let(:command) do
     Gitlab::Ci::Pipeline::Chain::Command.new(
-      project: project,
-      current_user: user, seeds_block: nil)
+      project: project, current_user: user)
   end
 
   let(:step) { described_class.new(pipeline, command) }
 
-  before do
-    step.perform!
-  end
-
   context 'when pipeline is ready to be saved' do
+    before do
+      pipeline.stages.build(name: 'test', project: project)
+
+      step.perform!
+    end
+
     it 'saves a pipeline' do
       expect(pipeline).to be_persisted
     end
@@ -32,6 +32,7 @@ describe Gitlab::Ci::Pipeline::Chain::Create do
 
     it 'creates stages' do
       expect(pipeline.reload.stages).to be_one
+      expect(pipeline.stages.first).to be_persisted
     end
   end
 
@@ -40,6 +41,10 @@ describe Gitlab::Ci::Pipeline::Chain::Create do
       build(:ci_pipeline, project: project, ref: nil)
     end
 
+    before do
+      step.perform!
+    end
+
     it 'breaks the chain' do
       expect(step.break?).to be true
     end
@@ -49,18 +54,4 @@ describe Gitlab::Ci::Pipeline::Chain::Create do
         .to include /Failed to persist the pipeline/
     end
   end
-
-  context 'when there is a seed block present' do
-    let(:seeds) { spy('pipeline seeds') }
-
-    let(:command) do
-      double('command', project: project,
-                        current_user: user,
-                        seeds_block: seeds)
-    end
-
-    it 'executes the block' do
-      expect(seeds).to have_received(:call).with(pipeline)
-    end
-  end
 end
diff --git a/spec/lib/gitlab/ci/pipeline/chain/populate_spec.rb b/spec/lib/gitlab/ci/pipeline/chain/populate_spec.rb
new file mode 100644
index 00000000000..2258ae83f38
--- /dev/null
+++ b/spec/lib/gitlab/ci/pipeline/chain/populate_spec.rb
@@ -0,0 +1,153 @@
+require 'spec_helper'
+
+describe Gitlab::Ci::Pipeline::Chain::Populate do
+  set(:project) { create(:project) }
+  set(:user) { create(:user) }
+
+  let(:pipeline) do
+    build(:ci_pipeline_with_one_job, project: project,
+                                     ref: 'master')
+  end
+
+  let(:command) do
+    Gitlab::Ci::Pipeline::Chain::Command.new(
+      project: project,
+      current_user: user,
+      seeds_block: nil)
+  end
+
+  let(:step) { described_class.new(pipeline, command) }
+
+  context 'when pipeline doesn not have seeds block' do
+    before do
+      step.perform!
+    end
+
+    it 'does not persist the pipeline' do
+      expect(pipeline).not_to be_persisted
+    end
+
+    it 'does not break the chain' do
+      expect(step.break?).to be false
+    end
+
+    it 'populates pipeline with stages' do
+      expect(pipeline.stages).to be_one
+      expect(pipeline.stages.first).not_to be_persisted
+    end
+
+    it 'populates pipeline with builds' do
+      expect(pipeline.builds).to be_one
+      expect(pipeline.builds.first).not_to be_persisted
+      expect(pipeline.stages.first.builds).to be_one
+      expect(pipeline.stages.first.builds.first).not_to be_persisted
+    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)
+    end
+
+    before do
+      step.perform!
+    end
+
+    it 'breaks the chain' do
+      expect(step.break?).to be true
+    end
+
+    it 'appends validation error' do
+      expect(pipeline.errors.to_a)
+        .to include 'Failed to build the pipeline!'
+    end
+  end
+
+  context 'when there is a seed blocks present' do
+    let(:command) do
+      Gitlab::Ci::Pipeline::Chain::Command.new(
+        project: project,
+        current_user: user,
+        seeds_block: seeds_block)
+    end
+
+    context 'when seeds block builds some resources' do
+      let(:seeds_block) do
+        ->(pipeline) { pipeline.variables.build(key: 'VAR', value: '123') }
+      end
+
+      it 'populates pipeline with resources described in the seeds block' do
+        step.perform!
+
+        expect(pipeline).not_to be_persisted
+        expect(pipeline.variables).not_to be_empty
+        expect(pipeline.variables.first).not_to be_persisted
+        expect(pipeline.variables.first.key).to eq 'VAR'
+        expect(pipeline.variables.first.value).to eq '123'
+      end
+    end
+
+    context 'when seeds block tries to persist some resources' do
+      let(:seeds_block) do
+        ->(pipeline) { pipeline.variables.create!(key: 'VAR', value: '123') }
+      end
+
+      it 'raises exception' do
+        expect { step.perform! }.to raise_error(ActiveRecord::RecordNotSaved)
+      end
+    end
+  end
+
+  context 'when pipeline gets persisted during the process' do
+    let(:pipeline) { create(:ci_pipeline, project: project) }
+
+    it 'raises error' do
+      expect { step.perform! }.to raise_error(described_class::PopulateError)
+    end
+  end
+
+  context 'when using only/except build policies' do
+    let(:config) do
+      { rspec: { script: 'rspec', stage: 'test', only: ['master'] },
+        prod: { script: 'cap prod', stage: 'deploy', only: ['tags'] } }
+    end
+
+    let(:pipeline) do
+      build(:ci_pipeline, ref: 'master', config: config)
+    end
+
+    it 'populates pipeline according to used policies' do
+      step.perform!
+
+      expect(pipeline.stages.size).to eq 1
+      expect(pipeline.builds.size).to eq 1
+      expect(pipeline.builds.first.name).to eq 'rspec'
+    end
+  end
+end
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: {} } }
 
diff --git a/spec/lib/gitlab/ci/pipeline/seed/build_spec.rb b/spec/lib/gitlab/ci/pipeline/seed/build_spec.rb
new file mode 100644
index 00000000000..116573379e0
--- /dev/null
+++ b/spec/lib/gitlab/ci/pipeline/seed/build_spec.rb
@@ -0,0 +1,242 @@
+require 'spec_helper'
+
+describe Gitlab::Ci::Pipeline::Seed::Build do
+  let(:pipeline) { create(:ci_empty_pipeline) }
+
+  let(:attributes) do
+    { name: 'rspec',
+      ref: 'master',
+      commands: 'rspec' }
+  end
+
+  subject do
+    described_class.new(pipeline, attributes)
+  end
+
+  describe '#attributes' do
+    it 'returns hash attributes of a build' do
+      expect(subject.attributes).to be_a Hash
+      expect(subject.attributes)
+        .to include(:name, :project, :ref, :commands)
+    end
+  end
+
+  describe '#user=' do
+    let(:user) { build(:user) }
+
+    it 'assignes user to a build' do
+      subject.user = user
+
+      expect(subject.attributes).to include(user: user)
+    end
+  end
+
+  describe '#to_resource' do
+    it 'returns a valid build resource' do
+      expect(subject.to_resource).to be_a(::Ci::Build)
+      expect(subject.to_resource).to be_valid
+    end
+
+    it 'memoizes a resource object' do
+      build = subject.to_resource
+
+      expect(build.object_id).to eq subject.to_resource.object_id
+    end
+
+    it 'can not be persisted without explicit assignment' do
+      build = subject.to_resource
+
+      pipeline.save!
+
+      expect(build).not_to be_persisted
+    end
+  end
+
+  describe 'applying only/except policies' do
+    context 'when no branch policy is specified' do
+      let(:attributes) { { name: 'rspec' } }
+
+      it { is_expected.to be_included }
+    end
+
+    context 'when branch policy does not match' do
+      context 'when using only' do
+        let(:attributes) { { name: 'rspec', only: { refs: ['deploy'] } } }
+
+        it { is_expected.not_to be_included }
+      end
+
+      context 'when using except' do
+        let(:attributes) { { name: 'rspec', except: { refs: ['deploy'] } } }
+
+        it { is_expected.to be_included }
+      end
+    end
+
+    context 'when branch regexp policy does not match' do
+      context 'when using only' do
+        let(:attributes) { { name: 'rspec', only: { refs: ['/^deploy$/'] } } }
+
+        it { is_expected.not_to be_included }
+      end
+
+      context 'when using except' do
+        let(:attributes) { { name: 'rspec', except: { refs: ['/^deploy$/'] } } }
+
+        it { is_expected.to be_included }
+      end
+    end
+
+    context 'when branch policy matches' do
+      context 'when using only' do
+        let(:attributes) { { name: 'rspec', only: { refs: %w[deploy master] } } }
+
+        it { is_expected.to be_included }
+      end
+
+      context 'when using except' do
+        let(:attributes) { { name: 'rspec', except: { refs: %w[deploy master] } } }
+
+        it { is_expected.not_to be_included }
+      end
+    end
+
+    context 'when keyword policy matches' do
+      context 'when using only' do
+        let(:attributes) { { name: 'rspec', only: { refs: ['branches'] } } }
+
+        it { is_expected.to be_included }
+      end
+
+      context 'when using except' do
+        let(:attributes) { { name: 'rspec', except: { refs: ['branches'] } } }
+
+        it { is_expected.not_to be_included }
+      end
+    end
+
+    context 'when keyword policy does not match' do
+      context 'when using only' do
+        let(:attributes) { { name: 'rspec', only: { refs: ['tags'] } } }
+
+        it { is_expected.not_to be_included }
+      end
+
+      context 'when using except' do
+        let(:attributes) { { name: 'rspec', except: { refs: ['tags'] } } }
+
+        it { is_expected.to be_included }
+      end
+    end
+
+    context 'when keywords and pipeline source policy matches' do
+      possibilities = [%w[pushes push],
+                       %w[web web],
+                       %w[triggers trigger],
+                       %w[schedules schedule],
+                       %w[api api],
+                       %w[external external]]
+
+      context 'when using only' do
+        possibilities.each do |keyword, source|
+          context "when using keyword `#{keyword}` and source `#{source}`" do
+            let(:pipeline) do
+              build(:ci_empty_pipeline, ref: 'deploy', tag: false, source: source)
+            end
+
+            let(:attributes) { { name: 'rspec', only: { refs: [keyword] } } }
+
+            it { is_expected.to be_included }
+          end
+        end
+      end
+
+      context 'when using except' do
+        possibilities.each do |keyword, source|
+          context "when using keyword `#{keyword}` and source `#{source}`" do
+            let(:pipeline) do
+              build(:ci_empty_pipeline, ref: 'deploy', tag: false, source: source)
+            end
+
+            let(:attributes) { { name: 'rspec', except: { refs: [keyword] } } }
+
+            it { is_expected.not_to be_included }
+          end
+        end
+      end
+    end
+
+    context 'when keywords and pipeline source does not match' do
+      possibilities = [%w[pushes web],
+                       %w[web push],
+                       %w[triggers schedule],
+                       %w[schedules external],
+                       %w[api trigger],
+                       %w[external api]]
+
+      context 'when using only' do
+        possibilities.each do |keyword, source|
+          context "when using keyword `#{keyword}` and source `#{source}`" do
+            let(:pipeline) do
+              build(:ci_empty_pipeline, ref: 'deploy', tag: false, source: source)
+            end
+
+            let(:attributes) { { name: 'rspec', only: { refs: [keyword] } } }
+
+            it { is_expected.not_to be_included }
+          end
+        end
+      end
+
+      context 'when using except' do
+        possibilities.each do |keyword, source|
+          context "when using keyword `#{keyword}` and source `#{source}`" do
+            let(:pipeline) do
+              build(:ci_empty_pipeline, ref: 'deploy', tag: false, source: source)
+            end
+
+            let(:attributes) { { name: 'rspec', except: { refs: [keyword] } } }
+
+            it { is_expected.to be_included }
+          end
+        end
+      end
+    end
+
+    context 'when repository path matches' do
+      context 'when using only' do
+        let(:attributes) do
+          { name: 'rspec', only: { refs: ["branches@#{pipeline.project_full_path}"] } }
+        end
+
+        it { is_expected.to be_included }
+      end
+
+      context 'when using except' do
+        let(:attributes) do
+          { name: 'rspec', except: { refs: ["branches@#{pipeline.project_full_path}"] } }
+        end
+
+        it { is_expected.not_to be_included }
+      end
+    end
+
+    context 'when repository path does not matches' do
+      context 'when using only' do
+        let(:attributes) do
+          { name: 'rspec', only: { refs: ['branches@fork'] } }
+        end
+
+        it { is_expected.not_to be_included }
+      end
+
+      context 'when using except' do
+        let(:attributes) do
+          { name: 'rspec', except: { refs: ['branches@fork'] } }
+        end
+
+        it { is_expected.to be_included }
+      end
+    end
+  end
+end
diff --git a/spec/lib/gitlab/ci/pipeline/seed/stage_spec.rb b/spec/lib/gitlab/ci/pipeline/seed/stage_spec.rb
new file mode 100644
index 00000000000..8f0bf40d624
--- /dev/null
+++ b/spec/lib/gitlab/ci/pipeline/seed/stage_spec.rb
@@ -0,0 +1,133 @@
+require 'spec_helper'
+
+describe Gitlab::Ci::Pipeline::Seed::Stage do
+  let(:pipeline) { create(:ci_empty_pipeline) }
+
+  let(:attributes) do
+    { name: 'test',
+      index: 0,
+      builds: [{ name: 'rspec' },
+               { name: 'spinach' },
+               { name: 'deploy', only: { refs: ['feature'] } }] }
+  end
+
+  subject do
+    described_class.new(pipeline, attributes)
+  end
+
+  describe '#size' do
+    it 'returns a number of jobs in the stage' do
+      expect(subject.size).to eq 2
+    end
+  end
+
+  describe '#attributes' do
+    it 'returns hash attributes of a stage' do
+      expect(subject.attributes).to be_a Hash
+      expect(subject.attributes).to include(:name, :project)
+    end
+  end
+
+  describe '#included?' do
+    context 'when it contains builds seeds' do
+      let(:attributes) do
+        { name: 'test',
+          index: 0,
+          builds: [{ name: 'deploy', only: { refs: ['master'] } }] }
+      end
+
+      it { is_expected.to be_included }
+    end
+
+    context 'when it does not contain build seeds' do
+      let(:attributes) do
+        { name: 'test',
+          index: 0,
+          builds: [{ name: 'deploy', only: { refs: ['feature'] } }] }
+      end
+
+      it { is_expected.not_to be_included }
+    end
+  end
+
+  describe '#seeds' do
+    it 'returns build seeds' do
+      expect(subject.seeds).to all(be_a Gitlab::Ci::Pipeline::Seed::Build)
+    end
+
+    it 'returns build seeds including valid attributes' do
+      expect(subject.seeds.size).to eq 2
+      expect(subject.seeds.map(&:attributes)).to all(include(ref: 'master'))
+      expect(subject.seeds.map(&:attributes)).to all(include(tag: false))
+      expect(subject.seeds.map(&:attributes)).to all(include(project: pipeline.project))
+      expect(subject.seeds.map(&:attributes))
+        .to all(include(trigger_request: pipeline.trigger_requests.first))
+    end
+
+    context 'when a ref is protected' do
+      before do
+        allow_any_instance_of(Project).to receive(:protected_for?).and_return(true)
+      end
+
+      it 'returns protected builds' do
+        expect(subject.seeds.map(&:attributes)).to all(include(protected: true))
+      end
+    end
+
+    context 'when a ref is not protected' do
+      before do
+        allow_any_instance_of(Project).to receive(:protected_for?).and_return(false)
+      end
+
+      it 'returns unprotected builds' do
+        expect(subject.seeds.map(&:attributes)).to all(include(protected: false))
+      end
+    end
+
+    it 'filters seeds using only/except policies' do
+      expect(subject.seeds.map(&:attributes)).to satisfy do |seeds|
+        seeds.any? { |hash| hash.fetch(:name) == 'rspec' }
+      end
+
+      expect(subject.seeds.map(&:attributes)).not_to satisfy do |seeds|
+        seeds.any? { |hash| hash.fetch(:name) == 'deploy' }
+      end
+    end
+  end
+
+  describe '#user=' do
+    let(:user) { build(:user) }
+
+    it 'assignes relevant pipeline attributes' do
+      subject.user = user
+
+      expect(subject.seeds.map(&:attributes)).to all(include(user: user))
+    end
+  end
+
+  describe '#to_resource' do
+    it 'builds a valid stage object with all builds' do
+      subject.to_resource.save!
+
+      expect(pipeline.reload.stages.count).to eq 1
+      expect(pipeline.reload.builds.count).to eq 2
+      expect(pipeline.builds).to all(satisfy { |job| job.stage_id.present? })
+      expect(pipeline.builds).to all(satisfy { |job| job.pipeline.present? })
+      expect(pipeline.builds).to all(satisfy { |job| job.project.present? })
+      expect(pipeline.stages)
+        .to all(satisfy { |stage| stage.pipeline.present? })
+      expect(pipeline.stages)
+        .to all(satisfy { |stage| stage.project.present? })
+    end
+
+    it 'can not be persisted without explicit pipeline assignment' do
+      stage = subject.to_resource
+
+      pipeline.save!
+
+      expect(stage).not_to be_persisted
+      expect(pipeline.reload.stages.count).to eq 0
+      expect(pipeline.reload.builds.count).to eq 0
+    end
+  end
+end
diff --git a/spec/lib/gitlab/ci/stage/seed_spec.rb b/spec/lib/gitlab/ci/stage/seed_spec.rb
deleted file mode 100644
index 3fe8d50c49a..00000000000
--- a/spec/lib/gitlab/ci/stage/seed_spec.rb
+++ /dev/null
@@ -1,83 +0,0 @@
-require 'spec_helper'
-
-describe Gitlab::Ci::Stage::Seed do
-  let(:pipeline) { create(:ci_empty_pipeline) }
-
-  let(:builds) do
-    [{ name: 'rspec' }, { name: 'spinach' }]
-  end
-
-  subject 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
-      expect(subject.stage).to include(:name, :project)
-    end
-  end
-
-  describe '#builds' do
-    it 'returns hash attributes of all builds' do
-      expect(subject.builds.size).to eq 2
-      expect(subject.builds).to all(include(ref: 'master'))
-      expect(subject.builds).to all(include(tag: false))
-      expect(subject.builds).to all(include(project: pipeline.project))
-      expect(subject.builds)
-        .to all(include(trigger_request: pipeline.trigger_requests.first))
-    end
-
-    context 'when a ref is protected' do
-      before do
-        allow_any_instance_of(Project).to receive(:protected_for?).and_return(true)
-      end
-
-      it 'returns protected builds' do
-        expect(subject.builds).to all(include(protected: true))
-      end
-    end
-
-    context 'when a ref is unprotected' do
-      before do
-        allow_any_instance_of(Project).to receive(:protected_for?).and_return(false)
-      end
-
-      it 'returns unprotected builds' do
-        expect(subject.builds).to all(include(protected: false))
-      end
-    end
-  end
-
-  describe '#user=' do
-    let(:user) { build(:user) }
-
-    it 'assignes relevant pipeline attributes' do
-      subject.user = user
-
-      expect(subject.builds).to all(include(user: user))
-    end
-  end
-
-  describe '#create!' do
-    it 'creates all stages and builds' do
-      subject.create!
-
-      expect(pipeline.reload.stages.count).to eq 1
-      expect(pipeline.reload.builds.count).to eq 2
-      expect(pipeline.builds).to all(satisfy { |job| job.stage_id.present? })
-      expect(pipeline.builds).to all(satisfy { |job| job.pipeline.present? })
-      expect(pipeline.builds).to all(satisfy { |job| job.project.present? })
-      expect(pipeline.stages)
-        .to all(satisfy { |stage| stage.pipeline.present? })
-      expect(pipeline.stages)
-        .to all(satisfy { |stage| stage.project.present? })
-    end
-  end
-end
diff --git a/spec/lib/gitlab/ci/yaml_processor_spec.rb b/spec/lib/gitlab/ci/yaml_processor_spec.rb
index f83f932e61e..fbc2af29b98 100644
--- a/spec/lib/gitlab/ci/yaml_processor_spec.rb
+++ b/spec/lib/gitlab/ci/yaml_processor_spec.rb
@@ -18,6 +18,34 @@ module Gitlab
       describe '#build_attributes' do
         subject { described_class.new(config).build_attributes(:rspec) }
 
+        describe 'attributes list' do
+          let(:config) do
+            YAML.dump(
+              before_script: ['pwd'],
+              rspec: { script: 'rspec' }
+            )
+          end
+
+          it 'returns valid build attributes' do
+            expect(subject).to eq({
+              stage: "test",
+              stage_idx: 1,
+              name: "rspec",
+              commands: "pwd\nrspec",
+              coverage_regex: nil,
+              tag_list: [],
+              options: {
+                before_script: ["pwd"],
+                script: ["rspec"]
+              },
+              allow_failure: false,
+              when: "on_success",
+              environment: nil,
+              yaml_variables: []
+            })
+          end
+        end
+
         describe 'coverage entry' do
           describe 'code coverage regexp' do
             let(:config) do
@@ -105,512 +133,118 @@ module Gitlab
         end
       end
 
-      describe '#stage_seeds' do
-        context 'when no refs policy is specified' do
-          let(:config) do
-            YAML.dump(production: { stage: 'deploy', script: 'cap prod' },
-                      rspec: { stage: 'test', script: 'rspec' },
-                      spinach: { stage: 'test', script: 'spinach' })
-          end
-
-          let(:pipeline) { create(:ci_empty_pipeline) }
-
-          it 'correctly fabricates a stage seeds object' do
-            seeds = subject.stage_seeds(pipeline)
-
-            expect(seeds.size).to eq 2
-            expect(seeds.first.stage[:name]).to eq 'test'
-            expect(seeds.second.stage[:name]).to eq 'deploy'
-            expect(seeds.first.builds.dig(0, :name)).to eq 'rspec'
-            expect(seeds.first.builds.dig(1, :name)).to eq 'spinach'
-            expect(seeds.second.builds.dig(0, :name)).to eq 'production'
-          end
-        end
-
-        context 'when refs policy is specified' do
-          let(:config) do
-            YAML.dump(production: { stage: 'deploy', script: 'cap prod', only: ['master'] },
-                      spinach: { stage: 'test', script: 'spinach', only: ['tags'] })
-          end
-
-          let(:pipeline) do
-            create(:ci_empty_pipeline, ref: 'feature', tag: true)
-          end
-
-          it 'returns stage seeds only assigned to master to master' do
-            seeds = subject.stage_seeds(pipeline)
-
-            expect(seeds.size).to eq 1
-            expect(seeds.first.stage[:name]).to eq 'test'
-            expect(seeds.first.builds.dig(0, :name)).to eq 'spinach'
-          end
-        end
-
-        context 'when source policy is specified' do
-          let(:config) do
-            YAML.dump(production: { stage: 'deploy', script: 'cap prod', only: ['triggers'] },
-                      spinach: { stage: 'test', script: 'spinach', only: ['schedules'] })
-          end
-
-          let(:pipeline) do
-            create(:ci_empty_pipeline, source: :schedule)
-          end
-
-          it 'returns stage seeds only assigned to schedules' do
-            seeds = subject.stage_seeds(pipeline)
-
-            expect(seeds.size).to eq 1
-            expect(seeds.first.stage[:name]).to eq 'test'
-            expect(seeds.first.builds.dig(0, :name)).to eq 'spinach'
-          end
+      describe '#stages_attributes' do
+        let(:config) do
+          YAML.dump(
+            rspec: { script: 'rspec', stage: 'test', only: ['branches'] },
+            prod: { script: 'cap prod', stage: 'deploy', only: ['tags'] }
+          )
         end
 
-        context 'when kubernetes policy is specified' do
-          let(:config) do
-            YAML.dump(
-              spinach: { stage: 'test', script: 'spinach' },
-              production: {
-                stage: 'deploy',
-                script: 'cap',
-                only: { kubernetes: 'active' }
-              }
-            )
-          end
-
-          context 'when kubernetes is active' do
-            shared_examples 'same behavior between KubernetesService and Platform::Kubernetes' do
-              it 'returns seeds for kubernetes dependent job' do
-                seeds = subject.stage_seeds(pipeline)
-
-                expect(seeds.size).to eq 2
-                expect(seeds.first.builds.dig(0, :name)).to eq 'spinach'
-                expect(seeds.second.builds.dig(0, :name)).to eq 'production'
-              end
-            end
-
-            context 'when user configured kubernetes from Integration > Kubernetes' do
-              let(:project) { create(:kubernetes_project) }
-              let(:pipeline) { create(:ci_empty_pipeline, project: project) }
-
-              it_behaves_like 'same behavior between KubernetesService and Platform::Kubernetes'
-            end
-
-            context 'when user configured kubernetes from CI/CD > Clusters' do
-              let!(:cluster) { create(:cluster, :project, :provided_by_gcp) }
-              let(:project) { cluster.project }
-              let(:pipeline) { create(:ci_empty_pipeline, project: project) }
-
-              it_behaves_like 'same behavior between KubernetesService and Platform::Kubernetes'
-            end
-          end
-
-          context 'when kubernetes is not active' do
-            it 'does not return seeds for kubernetes dependent job' do
-              seeds = subject.stage_seeds(pipeline)
-
-              expect(seeds.size).to eq 1
-              expect(seeds.first.builds.dig(0, :name)).to eq 'spinach'
-            end
-          end
+        let(:attributes) do
+          [{ name: "build",
+             index: 0,
+             builds: [] },
+           { name: "test",
+             index: 1,
+             builds:
+               [{ stage_idx: 1,
+                  stage: "test",
+                  commands: "rspec",
+                  tag_list: [],
+                  name: "rspec",
+                  allow_failure: false,
+                  when: "on_success",
+                  environment: nil,
+                  coverage_regex: nil,
+                  yaml_variables: [],
+                  options: { script: ["rspec"] },
+                  only: { refs: ["branches"] },
+                  except: {} }] },
+           { name: "deploy",
+             index: 2,
+             builds:
+               [{ stage_idx: 2,
+                  stage: "deploy",
+                  commands: "cap prod",
+                  tag_list: [],
+                  name: "prod",
+                  allow_failure: false,
+                  when: "on_success",
+                  environment: nil,
+                  coverage_regex: nil,
+                  yaml_variables: [],
+                  options: { script: ["cap prod"] },
+                  only: { refs: ["tags"] },
+                  except: {} }] }]
+        end
+
+        it 'returns stages seed attributes' do
+          expect(subject.stages_attributes).to eq attributes
         end
       end
 
-      describe "#pipeline_stage_builds" do
-        let(:type) { 'test' }
+      describe 'only / except policies validations' do
+        context 'when `only` has an invalid value' do
+          let(:config) { { rspec: { script: "rspec", type: "test", only: only } } }
+          let(:processor) { Gitlab::Ci::YamlProcessor.new(YAML.dump(config)) }
 
-        it "returns builds if no branch specified" do
-          config = YAML.dump({
-            before_script: ["pwd"],
-            rspec: { script: "rspec" }
-          })
-
-          config_processor = Gitlab::Ci::YamlProcessor.new(config)
-
-          expect(config_processor.pipeline_stage_builds(type, pipeline(ref: "master")).size).to eq(1)
-          expect(config_processor.pipeline_stage_builds(type, pipeline(ref: "master")).first).to eq({
-            stage: "test",
-            stage_idx: 1,
-            name: "rspec",
-            commands: "pwd\nrspec",
-            coverage_regex: nil,
-            tag_list: [],
-            options: {
-              before_script: ["pwd"],
-              script: ["rspec"]
-            },
-            allow_failure: false,
-            when: "on_success",
-            environment: nil,
-            yaml_variables: []
-          })
-        end
-
-        describe 'only' do
-          it "does not return builds if only has another branch" do
-            config = YAML.dump({
-                                 before_script: ["pwd"],
-                                 rspec: { script: "rspec", only: ["deploy"] }
-                               })
-
-            config_processor = Gitlab::Ci::YamlProcessor.new(config)
-
-            expect(config_processor.pipeline_stage_builds(type, pipeline(ref: "master")).size).to eq(0)
-          end
-
-          it "does not return builds if only has regexp with another branch" do
-            config = YAML.dump({
-                                 before_script: ["pwd"],
-                                 rspec: { script: "rspec", only: ["/^deploy$/"] }
-                               })
-
-            config_processor = Gitlab::Ci::YamlProcessor.new(config)
-
-            expect(config_processor.pipeline_stage_builds(type, pipeline(ref: "master")).size).to eq(0)
-          end
-
-          it "returns builds if only has specified this branch" do
-            config = YAML.dump({
-                                 before_script: ["pwd"],
-                                 rspec: { script: "rspec", only: ["master"] }
-                               })
-
-            config_processor = Gitlab::Ci::YamlProcessor.new(config)
-
-            expect(config_processor.pipeline_stage_builds(type, pipeline(ref: "master")).size).to eq(1)
-          end
-
-          it "returns builds if only has a list of branches including specified" do
-            config = YAML.dump({
-                                 before_script: ["pwd"],
-                                 rspec: { script: "rspec", type: type, only: %w(master deploy) }
-                               })
-
-            config_processor = Gitlab::Ci::YamlProcessor.new(config)
-
-            expect(config_processor.pipeline_stage_builds(type, pipeline(ref: "deploy")).size).to eq(1)
-          end
-
-          it "returns builds if only has a branches keyword specified" do
-            config = YAML.dump({
-                                 before_script: ["pwd"],
-                                 rspec: { script: "rspec", type: type, only: ["branches"] }
-                               })
-
-            config_processor = Gitlab::Ci::YamlProcessor.new(config)
-
-            expect(config_processor.pipeline_stage_builds(type, pipeline(ref: "deploy")).size).to eq(1)
-          end
-
-          it "does not return builds if only has a tags keyword" do
-            config = YAML.dump({
-                                 before_script: ["pwd"],
-                                 rspec: { script: "rspec", type: type, only: ["tags"] }
-                               })
-
-            config_processor = Gitlab::Ci::YamlProcessor.new(config)
-
-            expect(config_processor.pipeline_stage_builds(type, pipeline(ref: "deploy")).size).to eq(0)
-          end
+          context 'when it is integer' do
+            let(:only) { 1 }
 
-          it "returns builds if only has special keywords specified and source matches" do
-            possibilities = [{ keyword: 'pushes', source: 'push' },
-                             { keyword: 'web', source: 'web' },
-                             { keyword: 'triggers', source: 'trigger' },
-                             { keyword: 'schedules', source: 'schedule' },
-                             { keyword: 'api', source: 'api' },
-                             { keyword: 'external', source: 'external' }]
-
-            possibilities.each do |possibility|
-              config = YAML.dump({
-                                   before_script: ["pwd"],
-                                   rspec: { script: "rspec", type: type, only: [possibility[:keyword]] }
-                                 })
-
-              config_processor = Gitlab::Ci::YamlProcessor.new(config)
-
-              expect(config_processor.pipeline_stage_builds(type, pipeline(ref: 'deploy', tag: false, source: possibility[:source])).size).to eq(1)
+            it do
+              expect { processor }.to raise_error(Gitlab::Ci::YamlProcessor::ValidationError,
+                                                  'jobs:rspec:only has to be either an array of conditions or a hash')
             end
           end
 
-          it "does not return builds if only has special keywords specified and source doesn't match" do
-            possibilities = [{ keyword: 'pushes', source: 'web' },
-                             { keyword: 'web', source: 'push' },
-                             { keyword: 'triggers', source: 'schedule' },
-                             { keyword: 'schedules', source: 'external' },
-                             { keyword: 'api', source: 'trigger' },
-                             { keyword: 'external', source: 'api' }]
-
-            possibilities.each do |possibility|
-              config = YAML.dump({
-                                   before_script: ["pwd"],
-                                   rspec: { script: "rspec", type: type, only: [possibility[:keyword]] }
-                                 })
-
-              config_processor = Gitlab::Ci::YamlProcessor.new(config)
+          context 'when it is an array of integers' do
+            let(:only) { [1, 1] }
 
-              expect(config_processor.pipeline_stage_builds(type, pipeline(ref: 'deploy', tag: false, source: possibility[:source])).size).to eq(0)
+            it do
+              expect { processor }.to raise_error(Gitlab::Ci::YamlProcessor::ValidationError,
+                                                  'jobs:rspec:only config should be an array of strings or regexps')
             end
           end
 
-          it "returns builds if only has current repository path" do
-            seed_pipeline = pipeline(ref: 'deploy')
-
-            config = YAML.dump({
-                                 before_script: ["pwd"],
-                                 rspec: {
-                                   script: "rspec",
-                                   type: type,
-                                   only: ["branches@#{seed_pipeline.project_full_path}"]
-                                 }
-                               })
-
-            config_processor = Gitlab::Ci::YamlProcessor.new(config)
+          context 'when it is invalid regex' do
+            let(:only) { ["/*invalid/"] }
 
-            expect(config_processor.pipeline_stage_builds(type, seed_pipeline).size).to eq(1)
-          end
-
-          it "does not return builds if only has different repository path" do
-            config = YAML.dump({
-                                 before_script: ["pwd"],
-                                 rspec: { script: "rspec", type: type, only: ["branches@fork"] }
-                               })
-
-            config_processor = Gitlab::Ci::YamlProcessor.new(config)
-
-            expect(config_processor.pipeline_stage_builds(type, pipeline(ref: "deploy")).size).to eq(0)
-          end
-
-          it "returns build only for specified type" do
-            config = YAML.dump({
-                                 before_script: ["pwd"],
-                                 rspec: { script: "rspec", type: "test", only: %w(master deploy) },
-                                 staging: { script: "deploy", type: "deploy", only: %w(master deploy) },
-                                 production: { script: "deploy", type: "deploy", only: ["master@path", "deploy"] }
-                               })
-
-            config_processor = Gitlab::Ci::YamlProcessor.new(config)
-
-            expect(config_processor.pipeline_stage_builds("deploy", pipeline(ref: "deploy")).size).to eq(2)
-            expect(config_processor.pipeline_stage_builds("test", pipeline(ref: "deploy")).size).to eq(1)
-            expect(config_processor.pipeline_stage_builds("deploy", pipeline(ref: "master")).size).to eq(1)
-          end
-
-          context 'for invalid value' do
-            let(:config) { { rspec: { script: "rspec", type: "test", only: only } } }
-            let(:processor) { Gitlab::Ci::YamlProcessor.new(YAML.dump(config)) }
-
-            context 'when it is integer' do
-              let(:only) { 1 }
-
-              it do
-                expect { processor }.to raise_error(Gitlab::Ci::YamlProcessor::ValidationError,
-                                                    'jobs:rspec:only has to be either an array of conditions or a hash')
-              end
-            end
-
-            context 'when it is an array of integers' do
-              let(:only) { [1, 1] }
-
-              it do
-                expect { processor }.to raise_error(Gitlab::Ci::YamlProcessor::ValidationError,
-                                                    'jobs:rspec:only config should be an array of strings or regexps')
-              end
-            end
-
-            context 'when it is invalid regex' do
-              let(:only) { ["/*invalid/"] }
-
-              it do
-                expect { processor }.to raise_error(Gitlab::Ci::YamlProcessor::ValidationError,
-                                                    'jobs:rspec:only config should be an array of strings or regexps')
-              end
+            it do
+              expect { processor }.to raise_error(Gitlab::Ci::YamlProcessor::ValidationError,
+                                                  'jobs:rspec:only config should be an array of strings or regexps')
             end
           end
         end
 
-        describe 'except' do
-          it "returns builds if except has another branch" do
-            config = YAML.dump({
-                                 before_script: ["pwd"],
-                                 rspec: { script: "rspec", except: ["deploy"] }
-                               })
-
-            config_processor = Gitlab::Ci::YamlProcessor.new(config)
-
-            expect(config_processor.pipeline_stage_builds(type, pipeline(ref: "master")).size).to eq(1)
-          end
-
-          it "returns builds if except has regexp with another branch" do
-            config = YAML.dump({
-                                 before_script: ["pwd"],
-                                 rspec: { script: "rspec", except: ["/^deploy$/"] }
-                               })
-
-            config_processor = Gitlab::Ci::YamlProcessor.new(config)
+        context 'when `except` has an invalid value' do
+          let(:config) { { rspec: { script: "rspec", except: except } } }
+          let(:processor) { Gitlab::Ci::YamlProcessor.new(YAML.dump(config)) }
 
-            expect(config_processor.pipeline_stage_builds(type, pipeline(ref: "master")).size).to eq(1)
-          end
-
-          it "does not return builds if except has specified this branch" do
-            config = YAML.dump({
-                                 before_script: ["pwd"],
-                                 rspec: { script: "rspec", except: ["master"] }
-                               })
-
-            config_processor = Gitlab::Ci::YamlProcessor.new(config)
-
-            expect(config_processor.pipeline_stage_builds(type, pipeline(ref: "master")).size).to eq(0)
-          end
-
-          it "does not return builds if except has a list of branches including specified" do
-            config = YAML.dump({
-                                 before_script: ["pwd"],
-                                 rspec: { script: "rspec", type: type, except: %w(master deploy) }
-                               })
+          context 'when it is integer' do
+            let(:except) { 1 }
 
-            config_processor = Gitlab::Ci::YamlProcessor.new(config)
-
-            expect(config_processor.pipeline_stage_builds(type, pipeline(ref: "deploy")).size).to eq(0)
-          end
-
-          it "does not return builds if except has a branches keyword specified" do
-            config = YAML.dump({
-                                 before_script: ["pwd"],
-                                 rspec: { script: "rspec", type: type, except: ["branches"] }
-                               })
-
-            config_processor = Gitlab::Ci::YamlProcessor.new(config)
-
-            expect(config_processor.pipeline_stage_builds(type, pipeline(ref: "deploy")).size).to eq(0)
-          end
-
-          it "returns builds if except has a tags keyword" do
-            config = YAML.dump({
-                                 before_script: ["pwd"],
-                                 rspec: { script: "rspec", type: type, except: ["tags"] }
-                               })
-
-            config_processor = Gitlab::Ci::YamlProcessor.new(config)
-
-            expect(config_processor.pipeline_stage_builds(type, pipeline(ref: "deploy")).size).to eq(1)
-          end
-
-          it "does not return builds if except has special keywords specified and source matches" do
-            possibilities = [{ keyword: 'pushes', source: 'push' },
-                             { keyword: 'web', source: 'web' },
-                             { keyword: 'triggers', source: 'trigger' },
-                             { keyword: 'schedules', source: 'schedule' },
-                             { keyword: 'api', source: 'api' },
-                             { keyword: 'external', source: 'external' }]
-
-            possibilities.each do |possibility|
-              config = YAML.dump({
-                                   before_script: ["pwd"],
-                                   rspec: { script: "rspec", type: type, except: [possibility[:keyword]] }
-                                 })
-
-              config_processor = Gitlab::Ci::YamlProcessor.new(config)
-
-              expect(config_processor.pipeline_stage_builds(type, pipeline(ref: 'deploy', tag: false, source: possibility[:source])).size).to eq(0)
+            it do
+              expect { processor }.to raise_error(Gitlab::Ci::YamlProcessor::ValidationError,
+                                                  'jobs:rspec:except has to be either an array of conditions or a hash')
             end
           end
 
-          it "returns builds if except has special keywords specified and source doesn't match" do
-            possibilities = [{ keyword: 'pushes', source: 'web' },
-                             { keyword: 'web', source: 'push' },
-                             { keyword: 'triggers', source: 'schedule' },
-                             { keyword: 'schedules', source: 'external' },
-                             { keyword: 'api', source: 'trigger' },
-                             { keyword: 'external', source: 'api' }]
-
-            possibilities.each do |possibility|
-              config = YAML.dump({
-                                   before_script: ["pwd"],
-                                   rspec: { script: "rspec", type: type, except: [possibility[:keyword]] }
-                                 })
+          context 'when it is an array of integers' do
+            let(:except) { [1, 1] }
 
-              config_processor = Gitlab::Ci::YamlProcessor.new(config)
-
-              expect(config_processor.pipeline_stage_builds(type, pipeline(ref: 'deploy', tag: false, source: possibility[:source])).size).to eq(1)
+            it do
+              expect { processor }.to raise_error(Gitlab::Ci::YamlProcessor::ValidationError,
+                                                  'jobs:rspec:except config should be an array of strings or regexps')
             end
           end
 
-          it "does not return builds if except has current repository path" do
-            seed_pipeline = pipeline(ref: 'deploy')
-
-            config = YAML.dump({
-                                 before_script: ["pwd"],
-                                 rspec: {
-                                   script: "rspec",
-                                   type: type,
-                                   except: ["branches@#{seed_pipeline.project_full_path}"]
-                                 }
-                               })
-
-            config_processor = Gitlab::Ci::YamlProcessor.new(config)
-
-            expect(config_processor.pipeline_stage_builds(type, seed_pipeline).size).to eq(0)
-          end
-
-          it "returns builds if except has different repository path" do
-            config = YAML.dump({
-                                 before_script: ["pwd"],
-                                 rspec: { script: "rspec", type: type, except: ["branches@fork"] }
-                               })
-
-            config_processor = Gitlab::Ci::YamlProcessor.new(config)
-
-            expect(config_processor.pipeline_stage_builds(type, pipeline(ref: "deploy")).size).to eq(1)
-          end
-
-          it "returns build except specified type" do
-            master_pipeline = pipeline(ref: 'master')
-            test_pipeline = pipeline(ref: 'test')
-            deploy_pipeline = pipeline(ref: 'deploy')
-
-            config = YAML.dump({
-                                 before_script: ["pwd"],
-                                 rspec: { script: "rspec", type: "test", except: ["master", "deploy", "test@#{test_pipeline.project_full_path}"] },
-                                 staging: { script: "deploy", type: "deploy", except: ["master"] },
-                                 production: { script: "deploy", type: "deploy", except: ["master@#{master_pipeline.project_full_path}"] }
-                               })
-
-            config_processor = Gitlab::Ci::YamlProcessor.new(config)
-
-            expect(config_processor.pipeline_stage_builds("deploy", deploy_pipeline).size).to eq(2)
-            expect(config_processor.pipeline_stage_builds("test", test_pipeline).size).to eq(0)
-            expect(config_processor.pipeline_stage_builds("deploy", master_pipeline).size).to eq(0)
-          end
-
-          context 'for invalid value' do
-            let(:config) { { rspec: { script: "rspec", except: except } } }
-            let(:processor) { Gitlab::Ci::YamlProcessor.new(YAML.dump(config)) }
+          context 'when it is invalid regex' do
+            let(:except) { ["/*invalid/"] }
 
-            context 'when it is integer' do
-              let(:except) { 1 }
-
-              it do
-                expect { processor }.to raise_error(Gitlab::Ci::YamlProcessor::ValidationError,
-                                                    'jobs:rspec:except has to be either an array of conditions or a hash')
-              end
-            end
-
-            context 'when it is an array of integers' do
-              let(:except) { [1, 1] }
-
-              it do
-                expect { processor }.to raise_error(Gitlab::Ci::YamlProcessor::ValidationError,
-                                                    'jobs:rspec:except config should be an array of strings or regexps')
-              end
-            end
-
-            context 'when it is invalid regex' do
-              let(:except) { ["/*invalid/"] }
-
-              it do
-                expect { processor }.to raise_error(Gitlab::Ci::YamlProcessor::ValidationError,
-                                                    'jobs:rspec:except config should be an array of strings or regexps')
-              end
+            it do
+              expect { processor }.to raise_error(Gitlab::Ci::YamlProcessor::ValidationError,
+                                                  'jobs:rspec:except config should be an array of strings or regexps')
             end
           end
         end
@@ -620,7 +254,7 @@ module Gitlab
         let(:config_data) { YAML.dump(config) }
         let(:config_processor) { Gitlab::Ci::YamlProcessor.new(config_data) }
 
-        subject { config_processor.pipeline_stage_builds("test", pipeline(ref: "master")).first }
+        subject { config_processor.stage_builds_attributes('test').first }
 
         describe "before_script" do
           context "in global context" do
@@ -703,8 +337,8 @@ module Gitlab
 
             config_processor = Gitlab::Ci::YamlProcessor.new(config)
 
-            expect(config_processor.pipeline_stage_builds("test", pipeline(ref: "master")).size).to eq(1)
-            expect(config_processor.pipeline_stage_builds("test", pipeline(ref: "master")).first).to eq({
+            expect(config_processor.stage_builds_attributes("test").size).to eq(1)
+            expect(config_processor.stage_builds_attributes("test").first).to eq({
               stage: "test",
               stage_idx: 1,
               name: "rspec",
@@ -738,8 +372,8 @@ module Gitlab
 
             config_processor = Gitlab::Ci::YamlProcessor.new(config)
 
-            expect(config_processor.pipeline_stage_builds("test", pipeline(ref: "master")).size).to eq(1)
-            expect(config_processor.pipeline_stage_builds("test", pipeline(ref: "master")).first).to eq({
+            expect(config_processor.stage_builds_attributes("test").size).to eq(1)
+            expect(config_processor.stage_builds_attributes("test").first).to eq({
               stage: "test",
               stage_idx: 1,
               name: "rspec",
@@ -771,8 +405,8 @@ module Gitlab
 
             config_processor = Gitlab::Ci::YamlProcessor.new(config)
 
-            expect(config_processor.pipeline_stage_builds("test", pipeline(ref: "master")).size).to eq(1)
-            expect(config_processor.pipeline_stage_builds("test", pipeline(ref: "master")).first).to eq({
+            expect(config_processor.stage_builds_attributes("test").size).to eq(1)
+            expect(config_processor.stage_builds_attributes("test").first).to eq({
               stage: "test",
               stage_idx: 1,
               name: "rspec",
@@ -800,8 +434,8 @@ module Gitlab
 
             config_processor = Gitlab::Ci::YamlProcessor.new(config)
 
-            expect(config_processor.pipeline_stage_builds("test", pipeline(ref: "master")).size).to eq(1)
-            expect(config_processor.pipeline_stage_builds("test", pipeline(ref: "master")).first).to eq({
+            expect(config_processor.stage_builds_attributes("test").size).to eq(1)
+            expect(config_processor.stage_builds_attributes("test").first).to eq({
               stage: "test",
               stage_idx: 1,
               name: "rspec",
@@ -946,8 +580,8 @@ module Gitlab
                                })
 
             config_processor = Gitlab::Ci::YamlProcessor.new(config)
+            builds = config_processor.stage_builds_attributes("test")
 
-            builds = config_processor.pipeline_stage_builds("test", pipeline(ref: "master"))
             expect(builds.size).to eq(1)
             expect(builds.first[:when]).to eq(when_state)
           end
@@ -978,8 +612,8 @@ module Gitlab
 
           config_processor = Gitlab::Ci::YamlProcessor.new(config)
 
-          expect(config_processor.pipeline_stage_builds("test", pipeline(ref: "master")).size).to eq(1)
-          expect(config_processor.pipeline_stage_builds("test", pipeline(ref: "master")).first[:options][:cache]).to eq(
+          expect(config_processor.stage_builds_attributes("test").size).to eq(1)
+          expect(config_processor.stage_builds_attributes("test").first[:options][:cache]).to eq(
             paths: ["logs/", "binaries/"],
             untracked: true,
             key: 'key',
@@ -997,8 +631,8 @@ module Gitlab
 
           config_processor = Gitlab::Ci::YamlProcessor.new(config)
 
-          expect(config_processor.pipeline_stage_builds("test", pipeline(ref: "master")).size).to eq(1)
-          expect(config_processor.pipeline_stage_builds("test", pipeline(ref: "master")).first[:options][:cache]).to eq(
+          expect(config_processor.stage_builds_attributes("test").size).to eq(1)
+          expect(config_processor.stage_builds_attributes("test").first[:options][:cache]).to eq(
             paths: ["logs/", "binaries/"],
             untracked: true,
             key: 'key',
@@ -1017,8 +651,8 @@ module Gitlab
 
           config_processor = Gitlab::Ci::YamlProcessor.new(config)
 
-          expect(config_processor.pipeline_stage_builds("test", pipeline(ref: "master")).size).to eq(1)
-          expect(config_processor.pipeline_stage_builds("test", pipeline(ref: "master")).first[:options][:cache]).to eq(
+          expect(config_processor.stage_builds_attributes("test").size).to eq(1)
+          expect(config_processor.stage_builds_attributes("test").first[:options][:cache]).to eq(
             paths: ["test/"],
             untracked: false,
             key: 'local',
@@ -1046,8 +680,8 @@ module Gitlab
 
           config_processor = Gitlab::Ci::YamlProcessor.new(config)
 
-          expect(config_processor.pipeline_stage_builds("test", pipeline(ref: "master")).size).to eq(1)
-          expect(config_processor.pipeline_stage_builds("test", pipeline(ref: "master")).first).to eq({
+          expect(config_processor.stage_builds_attributes("test").size).to eq(1)
+          expect(config_processor.stage_builds_attributes("test").first).to eq({
             stage: "test",
             stage_idx: 1,
             name: "rspec",
@@ -1083,8 +717,8 @@ module Gitlab
                                })
 
             config_processor = Gitlab::Ci::YamlProcessor.new(config)
+            builds = config_processor.stage_builds_attributes("test")
 
-            builds = config_processor.pipeline_stage_builds("test", pipeline(ref: "master"))
             expect(builds.size).to eq(1)
             expect(builds.first[:options][:artifacts][:when]).to eq(when_state)
           end
@@ -1099,7 +733,7 @@ module Gitlab
         end
 
         let(:processor) { Gitlab::Ci::YamlProcessor.new(YAML.dump(config)) }
-        let(:builds) { processor.pipeline_stage_builds('deploy', pipeline(ref: 'master')) }
+        let(:builds) { processor.stage_builds_attributes('deploy') }
 
         context 'when a production environment is specified' do
           let(:environment) { 'production' }
@@ -1256,7 +890,7 @@ module Gitlab
 
       describe "Hidden jobs" do
         let(:config_processor) { Gitlab::Ci::YamlProcessor.new(config) }
-        subject { config_processor.pipeline_stage_builds("test", pipeline(ref: "master")) }
+        subject { config_processor.stage_builds_attributes("test") }
 
         shared_examples 'hidden_job_handling' do
           it "doesn't create jobs that start with dot" do
@@ -1304,7 +938,7 @@ module Gitlab
 
       describe "YAML Alias/Anchor" do
         let(:config_processor) { Gitlab::Ci::YamlProcessor.new(config) }
-        subject { config_processor.pipeline_stage_builds("build", pipeline(ref: "master")) }
+        subject { config_processor.stage_builds_attributes("build") }
 
         shared_examples 'job_templates_handling' do
           it "is correctly supported for jobs" do
@@ -1344,13 +978,13 @@ module Gitlab
 
         context 'when template is a job' do
           let(:config) do
-            <<EOT
-job1: &JOBTMPL
-  stage: build
-  script: execute-script-for-job
+            <<~EOT
+            job1: &JOBTMPL
+              stage: build
+              script: execute-script-for-job
 
-job2: *JOBTMPL
-EOT
+            job2: *JOBTMPL
+            EOT
           end
 
           it_behaves_like 'job_templates_handling'
@@ -1358,15 +992,15 @@ EOT
 
         context 'when template is a hidden job' do
           let(:config) do
-            <<EOT
-.template: &JOBTMPL
-  stage: build
-  script: execute-script-for-job
+            <<~EOT
+            .template: &JOBTMPL
+              stage: build
+              script: execute-script-for-job
 
-job1: *JOBTMPL
+            job1: *JOBTMPL
 
-job2: *JOBTMPL
-EOT
+            job2: *JOBTMPL
+            EOT
           end
 
           it_behaves_like 'job_templates_handling'
@@ -1374,18 +1008,18 @@ EOT
 
         context 'when job adds its own keys to a template definition' do
           let(:config) do
-            <<EOT
-.template: &JOBTMPL
-  stage: build
-
-job1:
-  <<: *JOBTMPL
-  script: execute-script-for-job
-
-job2:
-  <<: *JOBTMPL
-  script: execute-script-for-job
-EOT
+            <<~EOT
+            .template: &JOBTMPL
+              stage: build
+
+            job1:
+              <<: *JOBTMPL
+              script: execute-script-for-job
+
+            job2:
+              <<: *JOBTMPL
+              script: execute-script-for-job
+            EOT
           end
 
           it_behaves_like 'job_templates_handling'
@@ -1724,10 +1358,6 @@ EOT
           it { is_expected.to be_nil }
         end
       end
-
-      def pipeline(**attributes)
-        build_stubbed(:ci_empty_pipeline, **attributes)
-      end
     end
   end
 end
diff --git a/spec/models/ci/pipeline_spec.rb b/spec/models/ci/pipeline_spec.rb
index 4635f8cfe9d..92f00cfbc19 100644
--- a/spec/models/ci/pipeline_spec.rb
+++ b/spec/models/ci/pipeline_spec.rb
@@ -177,6 +177,24 @@ describe Ci::Pipeline, :mailer do
     end
   end
 
+  describe '#protected_ref?' do
+    it 'delegates method to project' do
+      expect(pipeline).not_to be_protected_ref
+    end
+  end
+
+  describe '#legacy_trigger' do
+    let(:trigger_request) { create(:ci_trigger_request) }
+
+    before do
+      pipeline.trigger_requests << trigger_request
+    end
+
+    it 'returns first trigger request' do
+      expect(pipeline.legacy_trigger).to eq trigger_request
+    end
+  end
+
   describe '#auto_canceled?' do
     subject { pipeline.auto_canceled? }
 
@@ -215,142 +233,257 @@ describe Ci::Pipeline, :mailer do
   end
 
   describe 'pipeline stages' do
-    before do
-      create(:commit_status, pipeline: pipeline,
-                             stage: 'build',
-                             name: 'linux',
-                             stage_idx: 0,
-                             status: 'success')
-
-      create(:commit_status, pipeline: pipeline,
-                             stage: 'build',
-                             name: 'mac',
-                             stage_idx: 0,
-                             status: 'failed')
-
-      create(:commit_status, pipeline: pipeline,
-                             stage: 'deploy',
-                             name: 'staging',
-                             stage_idx: 2,
-                             status: 'running')
-
-      create(:commit_status, pipeline: pipeline,
-                             stage: 'test',
-                             name: 'rspec',
-                             stage_idx: 1,
-                             status: 'success')
-    end
-
     describe '#stage_seeds' do
-      let(:pipeline) do
-        build(:ci_pipeline, config: { rspec: { script: 'rake' } })
-      end
+      let(:pipeline) { build(:ci_pipeline, config: config) }
+      let(:config) { { rspec: { script: 'rake' } } }
 
       it 'returns preseeded stage seeds object' do
-        expect(pipeline.stage_seeds).to all(be_a Gitlab::Ci::Stage::Seed)
+        expect(pipeline.stage_seeds)
+          .to all(be_a Gitlab::Ci::Pipeline::Seed::Base)
         expect(pipeline.stage_seeds.count).to eq 1
       end
-    end
 
-    describe '#seeds_size' do
-      let(:pipeline) { build(:ci_pipeline_with_one_job) }
+      context 'when no refs policy is specified' do
+        let(:config) do
+          { production: { stage: 'deploy', script: 'cap prod' },
+            rspec: { stage: 'test', script: 'rspec' },
+            spinach: { stage: 'test', script: 'spinach' } }
+        end
 
-      it 'returns number of jobs in stage seeds' do
-        expect(pipeline.seeds_size).to eq 1
+        it 'correctly fabricates a stage seeds object' do
+          seeds = pipeline.stage_seeds
+
+          expect(seeds.size).to eq 2
+          expect(seeds.first.attributes[:name]).to eq 'test'
+          expect(seeds.second.attributes[:name]).to eq 'deploy'
+          expect(seeds.dig(0, 0, :name)).to eq 'rspec'
+          expect(seeds.dig(0, 1, :name)).to eq 'spinach'
+          expect(seeds.dig(1, 0, :name)).to eq 'production'
+        end
       end
-    end
 
-    describe '#legacy_stages' do
-      subject { pipeline.legacy_stages }
+      context 'when refs policy is specified' do
+        let(:pipeline) do
+          build(:ci_pipeline, ref: 'feature', tag: true, config: config)
+        end
 
-      context 'stages list' do
-        it 'returns ordered list of stages' do
-          expect(subject.map(&:name)).to eq(%w[build test deploy])
+        let(:config) do
+          { production: { stage: 'deploy', script: 'cap prod', only: ['master'] },
+            spinach: { stage: 'test', script: 'spinach', only: ['tags'] } }
+        end
+
+        it 'returns stage seeds only assigned to master to master' do
+          seeds = pipeline.stage_seeds
+
+          expect(seeds.size).to eq 1
+          expect(seeds.first.attributes[:name]).to eq 'test'
+          expect(seeds.dig(0, 0, :name)).to eq 'spinach'
         end
       end
 
-      context 'stages with statuses' do
-        let(:statuses) do
-          subject.map { |stage| [stage.name, stage.status] }
+      context 'when source policy is specified' do
+        let(:pipeline) { build(:ci_pipeline, source: :schedule, config: config) }
+
+        let(:config) do
+          { production: { stage: 'deploy', script: 'cap prod', only: ['triggers'] },
+            spinach: { stage: 'test', script: 'spinach', only: ['schedules'] } }
         end
 
-        it 'returns list of stages with correct statuses' do
-          expect(statuses).to eq([%w(build failed),
-                                  %w(test success),
-                                  %w(deploy running)])
+        it 'returns stage seeds only assigned to schedules' do
+          seeds = pipeline.stage_seeds
+
+          expect(seeds.size).to eq 1
+          expect(seeds.first.attributes[:name]).to eq 'test'
+          expect(seeds.dig(0, 0, :name)).to eq 'spinach'
         end
+      end
 
-        context 'when commit status is retried' do
-          before do
-            create(:commit_status, pipeline: pipeline,
-                                   stage: 'build',
-                                   name: 'mac',
-                                   stage_idx: 0,
-                                   status: 'success')
+      context 'when kubernetes policy is specified' do
+        let(:config) do
+          {
+            spinach: { stage: 'test', script: 'spinach' },
+            production: {
+              stage: 'deploy',
+              script: 'cap',
+              only: { kubernetes: 'active' }
+            }
+          }
+        end
+
+        context 'when kubernetes is active' do
+          shared_examples 'same behavior between KubernetesService and Platform::Kubernetes' do
+            it 'returns seeds for kubernetes dependent job' do
+              seeds = pipeline.stage_seeds
 
-            pipeline.process!
+              expect(seeds.size).to eq 2
+              expect(seeds.dig(0, 0, :name)).to eq 'spinach'
+              expect(seeds.dig(1, 0, :name)).to eq 'production'
+            end
           end
 
-          it 'ignores the previous state' do
-            expect(statuses).to eq([%w(build success),
-                                    %w(test success),
-                                    %w(deploy running)])
+          context 'when user configured kubernetes from Integration > Kubernetes' do
+            let(:project) { create(:kubernetes_project) }
+            let(:pipeline) { build(:ci_pipeline, project: project, config: config) }
+
+            it_behaves_like 'same behavior between KubernetesService and Platform::Kubernetes'
           end
-        end
-      end
 
-      context 'when there is a stage with warnings' do
-        before do
-          create(:commit_status, pipeline: pipeline,
-                                 stage: 'deploy',
-                                 name: 'prod:2',
-                                 stage_idx: 2,
-                                 status: 'failed',
-                                 allow_failure: true)
+          context 'when user configured kubernetes from CI/CD > Clusters' do
+            let!(:cluster) { create(:cluster, :project, :provided_by_gcp) }
+            let(:project) { cluster.project }
+            let(:pipeline) { build(:ci_pipeline, project: project, config: config) }
+
+            it_behaves_like 'same behavior between KubernetesService and Platform::Kubernetes'
+          end
         end
 
-        it 'populates stage with correct number of warnings' do
-          deploy_stage = pipeline.legacy_stages.third
+        context 'when kubernetes is not active' do
+          it 'does not return seeds for kubernetes dependent job' do
+            seeds = pipeline.stage_seeds
 
-          expect(deploy_stage).not_to receive(:statuses)
-          expect(deploy_stage).to have_warnings
+            expect(seeds.size).to eq 1
+            expect(seeds.dig(0, 0, :name)).to eq 'spinach'
+          end
         end
       end
     end
 
-    describe '#stages_count' do
-      it 'returns a valid number of stages' do
-        expect(pipeline.stages_count).to eq(3)
-      end
-    end
+    describe '#seeds_size' do
+      context 'when refs policy is specified' do
+        let(:config) do
+          { production: { stage: 'deploy', script: 'cap prod', only: ['master'] },
+            spinach: { stage: 'test', script: 'spinach', only: ['tags'] } }
+        end
 
-    describe '#stages_names' do
-      it 'returns a valid names of stages' do
-        expect(pipeline.stages_names).to eq(%w(build test deploy))
+        let(:pipeline) do
+          build(:ci_pipeline, ref: 'feature', tag: true, config: config)
+        end
+
+        it 'returns real seeds size' do
+          expect(pipeline.seeds_size).to eq 1
+        end
       end
     end
-  end
-
-  describe '#legacy_stage' do
-    subject { pipeline.legacy_stage('test') }
 
-    context 'with status in stage' do
+    describe 'legacy stages' do
       before do
-        create(:commit_status, pipeline: pipeline, stage: 'test')
+        create(:commit_status, pipeline: pipeline,
+                               stage: 'build',
+                               name: 'linux',
+                               stage_idx: 0,
+                               status: 'success')
+
+        create(:commit_status, pipeline: pipeline,
+                               stage: 'build',
+                               name: 'mac',
+                               stage_idx: 0,
+                               status: 'failed')
+
+        create(:commit_status, pipeline: pipeline,
+                               stage: 'deploy',
+                               name: 'staging',
+                               stage_idx: 2,
+                               status: 'running')
+
+        create(:commit_status, pipeline: pipeline,
+                               stage: 'test',
+                               name: 'rspec',
+                               stage_idx: 1,
+                               status: 'success')
+      end
+
+      describe '#legacy_stages' do
+        subject { pipeline.legacy_stages }
+
+        context 'stages list' do
+          it 'returns ordered list of stages' do
+            expect(subject.map(&:name)).to eq(%w[build test deploy])
+          end
+        end
+
+        context 'stages with statuses' do
+          let(:statuses) do
+            subject.map { |stage| [stage.name, stage.status] }
+          end
+
+          it 'returns list of stages with correct statuses' do
+            expect(statuses).to eq([%w(build failed),
+                                    %w(test success),
+                                    %w(deploy running)])
+          end
+
+          context 'when commit status is retried' do
+            before do
+              create(:commit_status, pipeline: pipeline,
+                                     stage: 'build',
+                                     name: 'mac',
+                                     stage_idx: 0,
+                                     status: 'success')
+
+              pipeline.process!
+            end
+
+            it 'ignores the previous state' do
+              expect(statuses).to eq([%w(build success),
+                                      %w(test success),
+                                      %w(deploy running)])
+            end
+          end
+        end
+
+        context 'when there is a stage with warnings' do
+          before do
+            create(:commit_status, pipeline: pipeline,
+                                   stage: 'deploy',
+                                   name: 'prod:2',
+                                   stage_idx: 2,
+                                   status: 'failed',
+                                   allow_failure: true)
+          end
+
+          it 'populates stage with correct number of warnings' do
+            deploy_stage = pipeline.legacy_stages.third
+
+            expect(deploy_stage).not_to receive(:statuses)
+            expect(deploy_stage).to have_warnings
+          end
+        end
+      end
+
+      describe '#stages_count' do
+        it 'returns a valid number of stages' do
+          expect(pipeline.stages_count).to eq(3)
+        end
       end
 
-      it { expect(subject).to be_a Ci::LegacyStage }
-      it { expect(subject.name).to eq 'test' }
-      it { expect(subject.statuses).not_to be_empty }
+      describe '#stages_names' do
+        it 'returns a valid names of stages' do
+          expect(pipeline.stages_names).to eq(%w(build test deploy))
+        end
+      end
     end
 
-    context 'without status in stage' do
-      before do
-        create(:commit_status, pipeline: pipeline, stage: 'build')
+    describe '#legacy_stage' do
+      subject { pipeline.legacy_stage('test') }
+
+      context 'with status in stage' do
+        before do
+          create(:commit_status, pipeline: pipeline, stage: 'test')
+        end
+
+        it { expect(subject).to be_a Ci::LegacyStage }
+        it { expect(subject.name).to eq 'test' }
+        it { expect(subject.statuses).not_to be_empty }
       end
 
-      it 'return stage object' do
-        is_expected.to be_nil
+      context 'without status in stage' do
+        before do
+          create(:commit_status, pipeline: pipeline, stage: 'build')
+        end
+
+        it 'return stage object' do
+          is_expected.to be_nil
+        end
       end
     end
   end
@@ -589,20 +722,6 @@ describe Ci::Pipeline, :mailer do
     end
   end
 
-  describe '#has_stage_seeds?' do
-    context 'when pipeline has stage seeds' do
-      subject { build(:ci_pipeline_with_one_job) }
-
-      it { is_expected.to have_stage_seeds }
-    end
-
-    context 'when pipeline does not have stage seeds' do
-      subject { create(:ci_pipeline_without_jobs) }
-
-      it { is_expected.not_to have_stage_seeds }
-    end
-  end
-
   describe '#has_warnings?' do
     subject { pipeline.has_warnings? }
 
diff --git a/spec/views/ci/lints/show.html.haml_spec.rb b/spec/views/ci/lints/show.html.haml_spec.rb
index 7724d54c569..ded320793ea 100644
--- a/spec/views/ci/lints/show.html.haml_spec.rb
+++ b/spec/views/ci/lints/show.html.haml_spec.rb
@@ -5,6 +5,7 @@ describe 'ci/lints/show' do
 
   describe 'XSS protection' do
     let(:config_processor) { Gitlab::Ci::YamlProcessor.new(YAML.dump(content)) }
+
     before do
       assign(:status, true)
       assign(:builds, config_processor.builds)