Allow to delete group milestones

app/assets/javascripts/pages/groups/milestones/show/index.js

 import initMilestonesShow from '~/pages/milestones/shared/init_milestones_show';
+import initDeleteMilestoneModal from '~/pages/milestones/shared/delete_milestone_modal_init';
+
 import Milestone from '~/milestone';
 
 document.addEventListener('DOMContentLoaded', () => {
   initMilestonesShow();
-
+  initDeleteMilestoneModal();
   Milestone.initDeprecationMessage();
 });

app/assets/javascripts/pages/milestones/shared/components/delete_milestone_modal.vue

@@ -40,8 +40,8 @@
         if (this.issueCount === 0 && this.mergeRequestCount === 0) {
           return sprintf(
             s__(`Milestones|
-You’re about to permanently delete the milestone %{milestoneTitle} from this project.
-%{milestoneTitle} is not currently used in any issues or merge requests.`),
+You’re about to permanently delete the milestone %{milestoneTitle}.
+This milestone is not currently used in any issues or merge requests.`),
             {
               milestoneTitle,
             },
@@ -51,7 +51,7 @@ You’re about to permanently delete the milestone %{milestoneTitle} from this p
 
         return sprintf(
           s__(`Milestones|
-You’re about to permanently delete the milestone %{milestoneTitle} from this project and remove it from %{issuesWithCount} and %{mergeRequestsWithCount}.
+You’re about to permanently delete the milestone %{milestoneTitle} and remove it from %{issuesWithCount} and %{mergeRequestsWithCount}.
 Once deleted, it cannot be undone or recovered.`),
           {
             milestoneTitle,

app/controllers/groups/milestones_controller.rb

@@ -2,8 +2,8 @@ class Groups::MilestonesController < Groups::ApplicationController
   include MilestoneActions
 
   before_action :group_projects
-  before_action :milestone, only: [:edit, :show, :update, :merge_requests, :participants, :labels]
-  before_action :authorize_admin_milestones!, only: [:edit, :new, :create, :update]
+  before_action :milestone, only: [:edit, :show, :update, :merge_requests, :participants, :labels, :destroy]
+  before_action :authorize_admin_milestones!, only: [:edit, :new, :create, :update, :destroy]
 
   def index
     respond_to do |format|
@@ -56,10 +56,21 @@ class Groups::MilestonesController < Groups::ApplicationController
     redirect_to milestone_path
   end
 
+  def destroy
+    return render_404 if @milestone.legacy_group_milestone?
+
+    Milestones::DestroyService.new(group, current_user).execute(@milestone)
+
+    respond_to do |format|
+      format.html { redirect_to group_milestones_path(group), status: :see_other }
+      format.js { head :ok }
+    end
+  end
+
   private
 
   def authorize_admin_milestones!
-    return render_404 unless can?(current_user, :admin_milestones, group)
+    return render_404 unless can?(current_user, :admin_milestone, group)
   end
 
   def milestone_params

app/policies/group_policy.rb

@@ -53,7 +53,7 @@ class GroupPolicy < BasePolicy
 
   rule { has_access }.enable :read_namespace
 
-  rule { developer }.enable :admin_milestones
+  rule { developer }.enable :admin_milestone
 
   rule { reporter }.policy do
     enable :admin_label

app/services/milestones/destroy_service.rb

@@ -3,8 +3,6 @@
 module Milestones
   class DestroyService < Milestones::BaseService
     def execute(milestone)
-      return unless milestone.project_milestone?
-
       Milestone.transaction do
         update_params = { milestone: nil }
 
@@ -16,15 +14,21 @@ module Milestones
           MergeRequests::UpdateService.new(parent, current_user, update_params).execute(merge_request)
         end
 
+        log_destroy_event_for(milestone)
+
+        milestone.destroy
+      end
+    end
+
+    def log_destroy_event_for(milestone)
+      return if milestone.group_milestone?
+
       event_service.destroy_milestone(milestone, current_user)
 
       Event.for_milestone_id(milestone.id).each do |event|
         event.target_id = nil
         event.save
       end
-
-        milestone.destroy
-      end
     end
   end
 end

app/views/groups/milestones/index.html.haml

@@ -5,7 +5,7 @@
 
   .nav-controls
     = render 'shared/milestones_sort_dropdown'
-    - if can?(current_user, :admin_milestones, @group)
+    - if can?(current_user, :admin_milestone, @group)
       = link_to "New milestone", new_group_milestone_path(@group), class: "btn btn-new"
 
 .milestones

app/views/projects/milestones/show.html.haml

@@ -43,18 +43,7 @@
         - else
           = link_to 'Reopen milestone', project_milestone_path(@project, @milestone, milestone: {state_event: :activate }), method: :put, class: "btn btn-reopen btn-nr btn-grouped"
 
-        %button.js-delete-milestone-button.btn.btn-grouped.btn-danger{ data: { toggle: 'modal',
-          target: '#delete-milestone-modal',
-          milestone_id: @milestone.id,
-          milestone_title: markdown_field(@milestone, :title),
-          milestone_url: project_milestone_path(@project, @milestone),
-          milestone_issue_count: @milestone.issues.count,
-          milestone_merge_request_count: @milestone.merge_requests.count },
-          disabled: true }
-          = _('Delete')
-          = icon('spin spinner', class: 'js-loading-icon hidden' )
-
-        #delete-milestone-modal
+        = render 'shared/milestones/delete_button'
 
       %a.btn.btn-default.btn-grouped.float-right.d-block.d-sm-none.js-sidebar-toggle{ href: "#" }
         = icon('angle-double-left')

app/views/shared/milestones/_delete_button.html.haml

+- milestone_url = @milestone.project_milestone? ? project_milestone_path(@project, @milestone) : group_milestone_path(@group, @milestone)
+
+%button.js-delete-milestone-button.btn.btn-grouped.btn-danger{ data: { toggle: 'modal',
+  target: '#delete-milestone-modal',
+  milestone_id: @milestone.id,
+  milestone_title: markdown_field(@milestone, :title),
+  milestone_url: milestone_url,
+  milestone_issue_count: @milestone.issues.count,
+  milestone_merge_request_count: @milestone.merge_requests.count },
+  disabled: true }
+  = _('Delete')
+  = icon('spin spinner', class: 'js-loading-icon hidden' )
+
+#delete-milestone-modal

app/views/shared/milestones/_milestone.html.haml

@@ -49,7 +49,7 @@
           - unless milestone.active?
             = link_to 'Reopen Milestone', project_milestone_path(@project, milestone, {state_event: :activate }), method: :put, class: "btn btn-grouped btn-reopen"
         - if @group
-          - if can?(current_user, :admin_milestones, @group)
+          - if can?(current_user, :admin_milestone, @group)
             - if milestone.closed?
               = link_to 'Reopen Milestone', group_milestone_route(milestone, {state_event: :activate }), method: :put, class: "btn btn-sm btn-grouped btn-reopen"
             - else

app/views/shared/milestones/_top.html.haml

@@ -23,7 +23,7 @@
       = milestone_date_range(milestone)
   - if group
     .float-right
-      - if can?(current_user, :admin_milestones, group)
+      - if can?(current_user, :admin_milestone, group)
         - if milestone.group_milestone?
           = link_to edit_group_milestone_path(group, milestone), class: "btn btn btn-grouped" do
             Edit
@@ -32,6 +32,9 @@
         - else
           = link_to 'Reopen Milestone', group_milestone_route(milestone, {state_event: :activate }), method: :put, class: "btn btn-grouped btn-reopen"
 
+        - unless is_dynamic_milestone
+          = render 'shared/milestones/delete_button'
+
 = render 'shared/milestones/deprecation_message' if is_dynamic_milestone
 
 .detail-page-description.milestone-detail

changelogs/unreleased/issue_36138.yml

+---
+title: Allow to delete group milestones
+merge_request:
+author:
+type: added

config/routes/group.rb

@@ -37,7 +37,7 @@ constraints(::Constraints::GroupUrlConstrainer.new) do
       post :toggle_subscription, on: :member
     end
 
-    resources :milestones, constraints: { id: %r{[^/]+} }, only: [:index, :show, :edit, :update, :new, :create] do
+    resources :milestones, constraints: { id: %r{[^/]+} } do
       member do
         get :merge_requests
         get :participants

doc/api/group_milestones.md

@@ -96,6 +96,19 @@ Parameters:
 - `start_date` (optional) - The start date of the milestone
 - `state_event` (optional) - The state event of the milestone (close|activate)
 
+## Delete group milestone
+
+Only for user with developer access to the group.
+
+```
+DELETE /groups/:id/milestones/:milestone_id
+```
+
+Parameters:
+
+- `id` (required) - The ID or [URL-encoded path of the group](README.md#namespaced-path-encoding) owned by the authenticated user
+- `milestone_id` (required) - The ID of the group's milestone
+
 ## Get all issues assigned to a single milestone
 
 Gets all issues assigned to a single group milestone.

lib/api/group_milestones.rb

@@ -41,7 +41,7 @@ module API
         use :optional_params
       end
       post ":id/milestones" do
-        authorize! :admin_milestones, user_group
+        authorize! :admin_milestone, user_group
 
         create_milestone_for(user_group)
       end
@@ -53,11 +53,21 @@ module API
         use :update_params
       end
       put ":id/milestones/:milestone_id" do
-        authorize! :admin_milestones, user_group
+        authorize! :admin_milestone, user_group
 
         update_milestone_for(user_group)
       end
 
+      desc 'Remove a project milestone'
+      delete ":id/milestones/:milestone_id" do
+        authorize! :admin_milestone, user_group
+
+        milestone = user_group.milestones.find(params[:milestone_id])
+        Milestones::DestroyService.new(user_group, current_user).execute(milestone)
+
+        status(204)
+      end
+
       desc 'Get all issues for a single group milestone' do
         success Entities::IssueBasic
       end

lib/api/project_milestones.rb

@@ -64,7 +64,8 @@ module API
       delete ":id/milestones/:milestone_id" do
         authorize! :admin_milestone, user_project
 
-        user_project.milestones.find(params[:milestone_id]).destroy
+        milestone = user_project.milestones.find(params[:milestone_id])
+        Milestones::DestroyService.new(user_project, current_user).execute(milestone)
 
         status(204)
       end

spec/controllers/groups/milestones_controller_spec.rb

@@ -141,6 +141,17 @@ describe Groups::MilestonesController do
     end
   end
 
+  describe "#destroy" do
+    let(:milestone) { create(:milestone, group: group) }
+
+    it "removes milestone" do
+      delete :destroy, group_id: group.to_param, id: milestone.iid, format: :js
+
+      expect(response).to be_success
+      expect { Milestone.find(milestone.id) }.to raise_exception(ActiveRecord::RecordNotFound)
+    end
+  end
+
   describe '#ensure_canonical_path' do
     before do
       sign_in(user)

spec/factories/milestones.rb

@@ -29,7 +29,7 @@ FactoryBot.define do
         milestone.project_id = evaluator.project_id
       elsif evaluator.parent
         id = evaluator.parent.id
-        evaluator.parent.is_a?(Group) ? board.group_id = id : evaluator.project_id = id
+        evaluator.parent.is_a?(Group) ? evaluator.group_id = id : evaluator.project_id = id
       else
         milestone.project = create(:project)
       end

spec/features/milestones/user_deletes_milestone_spec.rb

 require "rails_helper"
 
 describe "User deletes milestone", :js do
-  set(:user) { create(:user) }
-  set(:project) { create(:project) }
-  set(:milestone) { create(:milestone, project: project) }
+  let(:user) { create(:user) }
+  let(:group) { create(:group) }
+  let(:project) { create(:project, namespace: group) }
 
   before do
-    project.add_developer(user)
     sign_in(user)
-
-    visit(project_milestones_path(project))
   end
 
+  context "when milestone belongs to project" do
+    let!(:milestone) { create(:milestone, parent: project, title: "project milestone") }
+
     it "deletes milestone" do
+      project.add_developer(user)
+      visit(project_milestones_path(project))
       click_link(milestone.title)
       click_button("Delete")
       click_button("Delete milestone")
@@ -23,4 +25,22 @@ describe "User deletes milestone", :js do
 
       expect(page).to have_content("#{user.name} destroyed milestone")
     end
+  end
+
+  context "when milestone belongs to group" do
+    let!(:milestone_to_be_deleted) { create(:milestone, parent: group, title: "group milestone 1") }
+    let!(:milestone) { create(:milestone, parent: group, title: "group milestone 2") }
+
+    it "deletes milestone" do
+      group.add_developer(user)
+      visit(group_milestones_path(group))
+
+      click_link(milestone_to_be_deleted.title)
+      click_button("Delete")
+      click_button("Delete milestone")
+
+      expect(page).to have_content(milestone.title)
+      expect(page).not_to have_content(milestone_to_be_deleted)
+    end
+  end
 end

spec/policies/group_policy_spec.rb

@@ -17,7 +17,7 @@ describe GroupPolicy do
 
   let(:reporter_permissions) { [:admin_label] }
 
-  let(:developer_permissions) { [:admin_milestones] }
+  let(:developer_permissions) { [:admin_milestone] }
 
   let(:maintainer_permissions) do
     [

spec/requests/api/project_milestones_spec.rb

@@ -39,19 +39,6 @@ describe API::ProjectMilestones do
 
       expect(response).to have_gitlab_http_status(404)
     end
-
-    it "rejects a member with reporter access from deleting a milestone" do
-      delete api("/projects/#{project.id}/milestones/#{milestone.id}", reporter)
-
-      expect(response).to have_gitlab_http_status(403)
-    end
-
-    it 'deletes the milestone when the user has developer access to the project' do
-      delete api("/projects/#{project.id}/milestones/#{milestone.id}", user)
-
-      expect(project.milestones.find_by_id(milestone.id)).to be_nil
-      expect(response).to have_gitlab_http_status(204)
-    end
   end
 
   describe 'PUT /projects/:id/milestones/:milestone_id to test observer on close' do

spec/services/milestones/destroy_service_spec.rb

@@ -4,8 +4,6 @@ describe Milestones::DestroyService do
   let(:user) { create(:user) }
   let(:project) { create(:project) }
   let(:milestone) { create(:milestone, title: 'Milestone v1.0', project: project) }
-  let!(:issue) { create(:issue, project: project, milestone: milestone) }
-  let!(:merge_request) { create(:merge_request, source_project: project, milestone: milestone) }
 
   before do
     project.add_maintainer(user)
@@ -23,12 +21,23 @@ describe Milestones::DestroyService do
     end
 
     it 'deletes milestone id from issuables' do
+      issue = create(:issue, project: project, milestone: milestone)
+      merge_request = create(:merge_request, source_project: project, milestone: milestone)
+
       service.execute(milestone)
 
       expect(issue.reload.milestone).to be_nil
       expect(merge_request.reload.milestone).to be_nil
     end
 
+    it 'logs destroy event' do
+      service.execute(milestone)
+
+      event = Event.where(project_id: milestone.project_id, target_type: 'Milestone')
+
+      expect(event.count).to eq(1)
+    end
+
     context 'group milestones' do
       let(:group) { create(:group) }
       let(:group_milestone) { create(:milestone, group: group) }
@@ -38,13 +47,20 @@ describe Milestones::DestroyService do
         group.add_developer(user)
       end
 
-      it { expect(service.execute(group_milestone)).to be_nil }
+      it { expect(service.execute(group_milestone)).to eq(group_milestone) }
 
-      it 'does not update milestone issuables' do
-        expect(MergeRequests::UpdateService).not_to receive(:new)
-        expect(Issues::UpdateService).not_to receive(:new)
+      it 'deletes milestone id from issuables' do
+        issue = create(:issue, project: project, milestone: group_milestone)
+        merge_request = create(:merge_request, source_project: project, milestone: group_milestone)
 
         service.execute(group_milestone)
+
+        expect(issue.reload.milestone).to be_nil
+        expect(merge_request.reload.milestone).to be_nil
+      end
+
+      it 'does not log destroy event' do
+        expect { service.execute(group_milestone) }.not_to change { Event.count }
       end
     end
   end

spec/support/api/milestones_shared_examples.rb

@@ -204,6 +204,24 @@ shared_examples_for 'group and project milestones' do |route_definition|
     end
   end
 
+  describe "DELETE #{route_definition}/:milestone_id" do
+    it "rejects a member with reporter access from deleting a milestone" do
+      reporter = create(:user)
+      milestone.parent.add_reporter(reporter)
+
+      delete api(resource_route, reporter)
+
+      expect(response).to have_gitlab_http_status(403)
+    end
+
+    it 'deletes the milestone when the user has developer access to the project' do
+      delete api(resource_route, user)
+
+      expect(project.milestones.find_by_id(milestone.id)).to be_nil
+      expect(response).to have_gitlab_http_status(204)
+    end
+  end
+
   describe "GET #{route_definition}/:milestone_id/issues" do
     let(:issues_route) { "#{route}/#{milestone.id}/issues" }