Add back the Project#to_reference_with_postfix function since it can be used...

Add back the Project#to_reference_with_postfix function since it can be used in the ProjectReferenceFilter#link_to_project function

app/models/project.rb

@@ -902,6 +902,10 @@ class Project < ActiveRecord::Base
     end
   end
 
+  def to_reference_with_postfix
+    "#{to_reference(full: true)}#{self.class.reference_postfix}"
+  end
+
   # `from` argument can be a Namespace or Project.
   def to_reference(from = nil, full: false)
     if full || cross_namespace_reference?(from)

lib/banzai/filter/project_reference_filter.rb

@@ -102,7 +102,7 @@ module Banzai
       def link_to_project(project, link_content: nil)
         url = urls.project_url(project, only_path: context[:only_path])
         data = data_attribute(project: project.id)
-        content = link_content || project.full_path + Project.reference_postfix
+        content = link_content || project.to_reference_with_postfix
 
         link_tag(url, data, content, project.name)
       end

spec/lib/banzai/filter/project_reference_filter_spec.rb

@@ -8,7 +8,7 @@ describe Banzai::Filter::ProjectReferenceFilter do
   end
 
   def get_reference(project)
-    "#{project.to_reference(full: true)}#{Project.reference_postfix}"
+    project.to_reference_with_postfix
   end
 
   let(:project)   { create(:project, :public) }

spec/models/project_spec.rb

@@ -344,6 +344,15 @@ describe Project do
     it { is_expected.to delegate_method(:name).to(:owner).with_prefix(true).with_arguments(allow_nil: true) }
   end
 
+  describe '#to_reference_with_postfix' do
+    it 'returns the full path with reference_postfix' do
+      namespace = create(:namespace, path: 'sample-namespace')
+      project = create(:project, path: 'sample-project', namespace: namespace)
+
+      expect(project.to_reference_with_postfix).to eq 'sample-namespace/sample-project>'
+    end
+  end
+
   describe '#to_reference' do
     let(:owner)     { create(:user, name: 'Gitlab') }
     let(:namespace) { create(:namespace, path: 'sample-namespace', owner: owner) }