Extract on-call schedules license check

Extract on-call schedules license check into policy
and a single method

ee/app/finders/incident_management/oncall_schedules_finder.rb

@@ -9,7 +9,7 @@ module IncidentManagement
     end
 
     def execute
-      return IncidentManagement::OncallSchedule.none unless available? && allowed?
+      return IncidentManagement::OncallSchedule.none unless allowed?
 
       collection = project.incident_management_oncall_schedules
       collection = by_iid(collection)
@@ -21,11 +21,6 @@ module IncidentManagement
 
     attr_reader :current_user, :project, :params
 
-    def available?
-      Feature.enabled?(:oncall_schedules_mvc, project) &&
-        project.feature_available?(:oncall_schedules)
-    end
-
     def allowed?
       Ability.allowed?(current_user, :read_incident_management_oncall_schedule, project)
     end

ee/app/policies/ee/project_policy.rb

@@ -155,8 +155,7 @@ module EE
 
       with_scope :subject
       condition(:oncall_schedules_available) do
-        ::Feature.enabled?(:oncall_schedules_mvc, @subject) &&
-          @subject.feature_available?(:oncall_schedules)
+        ::Gitlab::IncidentManagement.oncall_schedules_available?(@subject)
       end
 
       rule { visual_review_bot }.policy do

ee/app/services/incident_management/oncall_schedules/create_service.rb

@@ -31,8 +31,7 @@ module IncidentManagement
       end
 
       def available?
-        Feature.enabled?(:oncall_schedules_mvc, project) &&
-          project.feature_available?(:oncall_schedules)
+        ::Gitlab::IncidentManagement.oncall_schedules_available?(project)
       end
 
       def error(message)

ee/app/services/incident_management/oncall_schedules/destroy_service.rb

@@ -31,8 +31,7 @@ module IncidentManagement
       end
 
       def available?
-        Feature.enabled?(:oncall_schedules_mvc, project) &&
-          project.feature_available?(:oncall_schedules)
+        ::Gitlab::IncidentManagement.oncall_schedules_available?(project)
       end
 
       def error(message)

ee/app/services/incident_management/oncall_schedules/update_service.rb

@@ -33,8 +33,7 @@ module IncidentManagement
       end
 
       def available?
-        Feature.enabled?(:oncall_schedules_mvc, project) &&
-          project.feature_available?(:oncall_schedules)
+        ::Gitlab::IncidentManagement.oncall_schedules_available?(project)
       end
 
       def error(message)

ee/lib/gitlab/incident_management.rb

+# frozen_string_literal: true
+
+module Gitlab
+  module IncidentManagement
+    def self.oncall_schedules_available?(project)
+      ::Feature.enabled?(:oncall_schedules_mvc, project) &&
+        project.feature_available?(:oncall_schedules)
+    end
+  end
+end

ee/spec/lib/gitlab/incident_management_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Gitlab::IncidentManagement do
+  let_it_be_with_refind(:project) { create(:project) }
+
+  describe '.oncall_schedules_available?' do
+    subject { described_class.oncall_schedules_available?(project) }
+
+    before do
+      stub_licensed_features(oncall_schedules: true)
+      stub_feature_flags(oncall_schedules_mvc: project)
+    end
+
+    it { is_expected.to be_truthy }
+
+    context 'when feature flag is disabled' do
+      before do
+        stub_feature_flags(oncall_schedules_mvc: false)
+      end
+
+      it { is_expected.to be_falsey }
+    end
+
+    context 'when there is no license' do
+      before do
+        stub_licensed_features(oncall_schedules: false)
+      end
+
+      it { is_expected.to be_falsey }
+    end
+  end
+end