Properly create a new deployment after build success

app/models/ci/build.rb

@@ -75,9 +75,13 @@ module Ci
         build.execute_hooks
       end
 
-      after_transition any: :success do |build|
+      after_transition any => [:success] do |build|
         if build.environment.present?
-          CreateDeploymentService.new(build.project, build.user, environment: build.environment).execute(build)
+          service = CreateDeploymentService.new(build.project, build.user,
+                                                environment: build.environment,
+                                                sha: build.sha, ref: build.ref,
+                                                tag: build.tag)
+          service.execute(build)
         end
       end
     end

spec/services/create_deployment_service_spec.rb

 require 'spec_helper'
 
 describe CreateDeploymentService, services: true do
-  let(:build) { create(:ci_build) }
-  let(:project) { build.project }
+  let(:project) { create(:empty_project) }
   let(:user) { create(:user) }
 
   let(:service) { described_class.new(project, user, params) }
@@ -11,7 +10,7 @@ describe CreateDeploymentService, services: true do
     let(:params) do
       { environment: 'production',
         ref: 'master',
-        sha: build.sha,
+        sha: '97de212e80737a608d939f648d959671fb0a0142',
       }
     end
 
@@ -43,7 +42,7 @@ describe CreateDeploymentService, services: true do
       let(:params) do
         { environment: 'name with spaces',
           ref: 'master',
-          sha: build.sha,
+          sha: '97de212e80737a608d939f648d959671fb0a0142',
         }
       end
 
@@ -56,4 +55,63 @@ describe CreateDeploymentService, services: true do
       end
     end
   end
+  
+  describe 'processing of builds' do
+    let(:environment) { nil }
+    
+    shared_examples 'does not create environment and deployment' do
+      it 'does not create a new environment' do
+        expect { subject }.not_to change { Environment.count }
+      end
+
+      it 'does not create a new deployment' do
+        expect { subject }.not_to change { Deployment.count }
+      end
+
+      it 'does not call a service' do
+        expect_any_instance_of(described_class).not_to receive(:execute)
+        subject
+      end
+    end
+
+    shared_examples 'does create environment and deployment' do
+      it 'does create a new environment' do
+        expect { subject }.to change { Environment.count }.by(1)
+      end
+
+      it 'does create a new deployment' do
+        expect { subject }.to change { Deployment.count }.by(1)
+      end
+
+      it 'does call a service' do
+        expect_any_instance_of(described_class).to receive(:execute)
+        subject
+      end
+    end
+
+    context 'without environment specified' do
+      let(:build) { create(:ci_build, project: project) }
+      
+      it_behaves_like 'does not create environment and deployment' do
+        subject { build.success }
+      end
+    end
+    
+    context 'when environment is specified' do
+      let(:pipeline) { create(:ci_pipeline, project: project) }
+      let(:build) { create(:ci_build, pipeline: pipeline, environment: 'production') }
+
+      context 'when build succeeds' do
+        it_behaves_like 'does create environment and deployment' do
+          subject { build.success }
+        end
+      end
+
+      context 'when build fails' do
+        it_behaves_like 'does not create environment and deployment' do
+          subject { build.drop }
+        end
+      end
+    end
+  end
 end