Add missing specs for Presenter

Also add missing interface in abstract class.

app/presenters/clusterable_presenter.rb

@@ -27,4 +27,24 @@ class ClusterablePresenter < Gitlab::View::Presenter::Delegated
   def clusterable_params
     raise NotImplementedError
   end
+
+  def create_user_clusters_path
+    raise NotImplementedError
+  end
+
+  def create_gcp_clusters_path
+    raise NotImplementedError
+  end
+
+  def cluster_status_cluster_path(cluster, params = {})
+    raise NotImplementedError
+  end
+
+  def install_applications_cluster_path(cluster, application)
+    raise NotImplementedError
+  end
+
+  def cluster_path(cluster, params = {})
+    raise NotImplementedError
+  end
 end

spec/presenters/project_clusterable_presenter_spec.rb

@@ -7,6 +7,7 @@ describe ProjectClusterablePresenter do
 
   let(:presenter) { described_class.new(project) }
   let(:project) { create(:project) }
+  let(:cluster) { create(:cluster, :provided_by_gcp, projects: [project]) }
 
   describe '#can_create_cluster?' do
     let(:user) { create(:user) }
@@ -42,6 +43,38 @@ describe ProjectClusterablePresenter do
     it { is_expected.to eq(new_project_cluster_path(project)) }
   end
 
+  describe '#create_user_clusters_path' do
+    subject { presenter.create_user_clusters_path }
+
+    it { is_expected.to eq(create_user_project_clusters_path(project)) }
+  end
+
+  describe '#create_gcp_clusters_path' do
+    subject { presenter.create_gcp_clusters_path }
+
+    it { is_expected.to eq(create_gcp_project_clusters_path(project)) }
+  end
+
+  describe '#cluster_status_cluster_path' do
+    subject { presenter.cluster_status_cluster_path(cluster) }
+
+    it { is_expected.to eq(cluster_status_project_cluster_path(project, cluster)) }
+  end
+
+  describe '#install_applications_cluster_path' do
+    let(:application) { :helm }
+
+    subject { presenter.install_applications_cluster_path(cluster, application) }
+
+    it { is_expected.to eq(install_applications_project_cluster_path(project, cluster, application)) }
+  end
+
+  describe '#cluster_path' do
+    subject { presenter.cluster_path(cluster) }
+
+    it { is_expected.to eq(project_cluster_path(project, cluster)) }
+  end
+
   describe '#clusterable_params' do
     subject { presenter.clusterable_params }