Merge branch '19988-prevent-empty-pagination-when-list-not-empty' into 'master'

adds kaminari_pagination controller concern with bounded pagination to not displ…

Closes #19988

See merge request !8172

9 files changed, 125 insertions, 2 deletions

diff --git a/app/controllers/dashboard/todos_controller.rb b/app/controllers/dashboard/todos_controller.rb
index d425d0f9014..e3933e3d7b1 100644
--- a/app/controllers/dashboard/todos_controller.rb
+++ b/app/controllers/dashboard/todos_controller.rb
@@ -4,6 +4,9 @@ class Dashboard::TodosController < Dashboard::ApplicationController
   def index
     @sort = params[:sort]
     @todos = @todos.page(params[:page])
+    if @todos.out_of_range? && @todos.total_pages != 0
+      redirect_to url_for(params.merge(page: @todos.total_pages))
+    end
   end
 
   def destroy
diff --git a/app/controllers/projects/issues_controller.rb b/app/controllers/projects/issues_controller.rb
index 4f66e01e0f7..2beb0df8a07 100644
--- a/app/controllers/projects/issues_controller.rb
+++ b/app/controllers/projects/issues_controller.rb
@@ -25,6 +25,9 @@ class Projects::IssuesController < Projects::ApplicationController
   def index
     @issues = issues_collection
     @issues = @issues.page(params[:page])
+    if @issues.out_of_range? && @issues.total_pages != 0
+      return redirect_to url_for(params.merge(page: @issues.total_pages))
+    end
 
     if params[:label_name].present?
       @labels = LabelsFinder.new(current_user, project_id: @project.id, title: params[:label_name]).execute
diff --git a/app/controllers/projects/merge_requests_controller.rb b/app/controllers/projects/merge_requests_controller.rb
index 3abebdfd032..fc8a289d49d 100644
--- a/app/controllers/projects/merge_requests_controller.rb
+++ b/app/controllers/projects/merge_requests_controller.rb
@@ -38,6 +38,9 @@ class Projects::MergeRequestsController < Projects::ApplicationController
   def index
     @merge_requests = merge_requests_collection
     @merge_requests = @merge_requests.page(params[:page])
+    if @merge_requests.out_of_range? && @merge_requests.total_pages != 0
+      return redirect_to url_for(params.merge(page: @merge_requests.total_pages))
+    end
 
     if params[:label_name].present?
       labels_params = { project_id: @project.id, title: params[:label_name] }
diff --git a/app/controllers/projects/snippets_controller.rb b/app/controllers/projects/snippets_controller.rb
index 0720be2e55d..02a97c1c574 100644
--- a/app/controllers/projects/snippets_controller.rb
+++ b/app/controllers/projects/snippets_controller.rb
@@ -26,6 +26,9 @@ class Projects::SnippetsController < Projects::ApplicationController
       scope: params[:scope]
     )
     @snippets = @snippets.page(params[:page])
+    if @snippets.out_of_range? && @snippets.total_pages != 0
+      redirect_to namespace_project_snippets_path(page: @snippets.total_pages)
+    end
   end
 
   def new
diff --git a/changelogs/unreleased/19988-prevent-empty-pagination-when-list-not-empty.yml b/changelogs/unreleased/19988-prevent-empty-pagination-when-list-not-empty.yml
new file mode 100644
index 00000000000..5570ede4a9a
--- /dev/null
+++ b/changelogs/unreleased/19988-prevent-empty-pagination-when-list-not-empty.yml
@@ -0,0 +1,4 @@
+---
+title: Prevent empty pagination when list is not empty
+merge_request: 8172
+author: 
diff --git a/spec/controllers/dashboard/todos_controller_spec.rb b/spec/controllers/dashboard/todos_controller_spec.rb
new file mode 100644
index 00000000000..288984cfba9
--- /dev/null
+++ b/spec/controllers/dashboard/todos_controller_spec.rb
@@ -0,0 +1,37 @@
+require 'spec_helper'
+
+describe Dashboard::TodosController do
+  let(:user) { create(:user) }
+  let(:project) { create(:project) }
+  let(:todo_service) { TodoService.new }
+
+  describe 'GET #index' do
+    before do
+      sign_in(user)
+      project.team << [user, :developer]
+    end
+
+    context 'when using pagination' do
+      let(:last_page) { user.todos.page().total_pages }
+      let!(:issues) { create_list(:issue, 2, project: project, assignee: user) }
+
+      before do
+        issues.each { |issue| todo_service.new_issue(issue, user) }
+        allow(Kaminari.config).to receive(:default_per_page).and_return(1)
+      end
+
+      it 'redirects to last_page if page number is larger than number of pages' do
+        get :index, page: (last_page + 1).to_param
+
+        expect(response).to redirect_to(dashboard_todos_path(page: last_page))
+      end
+
+      it 'redirects to correspondent page' do
+        get :index, page: last_page
+
+        expect(assigns(:todos).current_page).to eq(last_page)
+        expect(response).to have_http_status(200)
+      end
+    end
+  end
+end
diff --git a/spec/controllers/projects/issues_controller_spec.rb b/spec/controllers/projects/issues_controller_spec.rb
index dbe5ddccbcf..e2321f2034b 100644
--- a/spec/controllers/projects/issues_controller_spec.rb
+++ b/spec/controllers/projects/issues_controller_spec.rb
@@ -52,6 +52,36 @@ describe Projects::IssuesController do
         expect(response).to have_http_status(404)
       end
     end
+
+    context 'with page param' do
+      let(:last_page) { project.issues.page().total_pages }
+      let!(:issue_list) { create_list(:issue, 2, project: project) }
+
+      before do
+        sign_in(user)
+        project.team << [user, :developer]
+        allow(Kaminari.config).to receive(:default_per_page).and_return(1)
+      end
+
+      it 'redirects to last_page if page number is larger than number of pages' do
+        get :index,
+          namespace_id: project.namespace.path.to_param,
+          project_id: project.path.to_param,
+          page: (last_page + 1).to_param
+
+        expect(response).to redirect_to(namespace_project_issues_path(page: last_page, state: controller.params[:state], scope: controller.params[:scope]))
+      end
+
+      it 'redirects to specified page' do
+        get :index,
+          namespace_id: project.namespace.path.to_param,
+          project_id: project.path.to_param,
+          page: last_page.to_param
+
+        expect(assigns(:issues).current_page).to eq(last_page)
+        expect(response).to have_http_status(200)
+      end
+    end
   end
 
   describe 'GET #new' do
diff --git a/spec/controllers/projects/merge_requests_controller_spec.rb b/spec/controllers/projects/merge_requests_controller_spec.rb
index 440b897ddc6..2a411d78395 100644
--- a/spec/controllers/projects/merge_requests_controller_spec.rb
+++ b/spec/controllers/projects/merge_requests_controller_spec.rb
@@ -127,11 +127,29 @@ describe Projects::MergeRequestsController do
   end
 
   describe 'GET index' do
-    def get_merge_requests
+    def get_merge_requests(page = nil)
       get :index,
           namespace_id: project.namespace.to_param,
           project_id: project.to_param,
-          state: 'opened'
+          state: 'opened', page: page.to_param
+    end
+
+    context 'when page param' do
+      let(:last_page) { project.merge_requests.page().total_pages }
+      let!(:merge_request) { create(:merge_request_with_diffs, target_project: project, source_project: project) }
+
+      it 'redirects to last_page if page number is larger than number of pages' do
+        get_merge_requests(last_page + 1)
+
+        expect(response).to redirect_to(namespace_project_merge_requests_path(page: last_page, state: controller.params[:state], scope: controller.params[:scope]))
+      end
+
+      it 'redirects to specified page' do
+        get_merge_requests(last_page)
+
+        expect(assigns(:merge_requests).current_page).to eq(last_page)
+        expect(response).to have_http_status(200)
+      end
     end
 
     context 'when filtering by opened state' do
diff --git a/spec/controllers/projects/snippets_controller_spec.rb b/spec/controllers/projects/snippets_controller_spec.rb
index 72a3ebf2ebd..32b0e42c3cd 100644
--- a/spec/controllers/projects/snippets_controller_spec.rb
+++ b/spec/controllers/projects/snippets_controller_spec.rb
@@ -11,6 +11,28 @@ describe Projects::SnippetsController do
   end
 
   describe 'GET #index' do
+    context 'when page param' do
+      let(:last_page) { project.snippets.page().total_pages }
+      let!(:project_snippet) { create(:project_snippet, :public, project: project, author: user) }
+
+      it 'redirects to last_page if page number is larger than number of pages' do
+        get :index,
+          namespace_id: project.namespace.path,
+          project_id: project.path, page: (last_page + 1).to_param
+
+        expect(response).to redirect_to(namespace_project_snippets_path(page: last_page))
+      end
+
+      it 'redirects to specified page' do
+        get :index,
+          namespace_id: project.namespace.path,
+          project_id: project.path, page: last_page.to_param
+
+        expect(assigns(:snippets).current_page).to eq(last_page)
+        expect(response).to have_http_status(200)
+      end
+    end
+
     context 'when the project snippet is private' do
       let!(:project_snippet) { create(:project_snippet, :private, project: project, author: user) }