Use static status check name on GitHub integration

default GitHubService#static_context to true for new integrations

doc/user/project/integrations/github.md

@@ -30,19 +30,18 @@ with `repo:status` access granted:
 1. Select the "Active" checkbox.
 1. Paste the token you've generated on GitHub
 1. Enter the path to your project on GitHub, such as `https://github.com/username/repository`
-1. Optionally check "Static status check names" checkbox to enable static status check names.
+1. Optionally uncheck **Static status check names** checkbox to disable static status check names.
 1. Save or optionally click "Test Settings".
 
 #### Static / dynamic status check names
 
-Since GitLab 11.5 it is possible to opt-in to using static status check names.
+> - Introduced in GitLab 11.5: using static status check names as opt-in option.
+> - [In GitLab 12.4](https://gitlab.com/gitlab-org/gitlab-ee/issues/9931), static status check names is default behavior for new projects.
 
 This makes it possible to mark these status checks as _Required_ on GitHub.
-If you check "Static status check names" checkbox on the integration page, your
+With **Static status check names** enabled on the integration page, your
 GitLab instance host name is going to be appended to a status check name,
 whereas in case of dynamic status check names, a branch name is going to be
 appended.
 
-Dynamic status check name is a default behavior.
-
 ![Configure GitHub Project Integration](img/github_configuration.png)

ee/app/models/project_services/github_service.rb

@@ -14,6 +14,10 @@ class GithubService < Service
 
   default_value_for :pipeline_events, true
 
+  def initialize_properties
+    self.properties ||= { static_context: true }
+  end
+
   def title
     'GitHub'
   end

ee/app/services/ci_cd/github_integration_setup_service.rb

@@ -35,7 +35,8 @@ module CiCd
         {
           active: true,
           repository_url: repository_url,
-          token: github_access_token
+          token: github_access_token,
+          static_context: true
         }
       end
 

ee/changelogs/unreleased/9931-github-integration-default-static-status-check-names.yml

+---
+title: Use static status check names on GitHub integrations
+merge_request: 15737
+author:
+type: changed

ee/spec/models/project_services/github_service_spec.rb

@@ -76,6 +76,58 @@ describe GithubService do
     end
   end
 
+  describe '#properties' do
+    let(:properties) { subject.reload.properties.symbolize_keys }
+
+    it 'does not overwrite existing integrations' do
+      subject.update(service_params.slice(:properties))
+
+      expect(properties).to match(service_params[:properties])
+      expect(subject.static_context).to be_nil
+    end
+
+    context 'when initialized without properties' do
+      let(:service_params) do
+        {
+          active: false,
+          project: project
+        }
+      end
+
+      it 'static_context defaults to true' do
+        expect(properties).to match(static_context: true)
+      end
+    end
+
+    context 'when initialized with static_context as false' do
+      let(:service_params) do
+        {
+          active: false,
+          project: project,
+          static_context: false
+        }
+      end
+
+      it 'static_context remains false' do
+        expect(properties).to match(static_context: false)
+      end
+    end
+
+    context 'when initialized with static_context as false' do
+      let(:service_params) do
+        {
+          active: false,
+          project: project,
+          properties: { static_context: false }
+        }
+      end
+
+      it 'static_context remains false' do
+        expect(properties).to match(static_context: false)
+      end
+    end
+  end
+
   describe '#execute' do
     let(:remote_repo_path) { "#{owner}/#{repository_name}" }
     let(:sha) { pipeline.sha }

ee/spec/services/ci_cd/github_integration_setup_service_spec.rb

@@ -27,5 +27,9 @@ describe CiCd::GithubIntegrationSetupService do
     specify 'with repo URL' do
       expect(integration.repository_url).to eq 'https://github.com/MyUser/my-project'
     end
+
+    specify 'with static_context' do
+      expect(integration.static_context).to eq true
+    end
   end
 end