Redirect case sensitive project path to the normalized one

app/controllers/application_controller.rb

@@ -117,9 +117,14 @@ class ApplicationController < ActionController::Base
         redirect_to request.original_url.gsub(/\.git\Z/, '') and return
       end
 
-      @project = Project.find_with_namespace("#{namespace}/#{id}")
+      project_path = "#{namespace}/#{id}"
+      @project = Project.find_with_namespace(project_path)
+
 
       if @project and can?(current_user, :read_project, @project)
+        if @project.path_with_namespace != project_path
+          redirect_to request.original_url.gsub(project_path, @project.path_with_namespace) and return
+        end
         @project
       elsif current_user.nil?
         @project = nil

spec/controllers/projects/issues_controller_spec.rb

@@ -17,6 +17,12 @@ describe Projects::IssuesController do
       expect(response.status).to eq(200)
     end
 
+    it "return 301 if request path doesn't match project path" do
+      get :index, namespace_id: project.namespace.path, project_id: project.path.upcase
+
+      expect(response).to redirect_to(namespace_project_issues_path(project.namespace, project))
+    end
+
     it "returns 404 when issues are disabled" do
       project.issues_enabled = false
       project.save

spec/controllers/projects_controller_spec.rb

@@ -21,6 +21,20 @@ describe ProjectsController do
         expect(response.body).to include("content='#{content}'")
       end
     end
+
+    context "when requested with case sensitive namespace and project path" do
+      it "redirects to the normalized path for case mismatch" do
+       get :show, namespace_id: public_project.namespace.path, id: public_project.path.upcase
+
+       expect(response).to redirect_to("/#{public_project.path_with_namespace}")
+      end
+
+      it "loads the page if normalized path matches request path" do
+        get :show, namespace_id: public_project.namespace.path, id: public_project.path
+
+        expect(response.status).to eq(200)
+      end
+    end
   end
 
   describe "POST #toggle_star" do