Added slash command to close an issue as a duplicate. Closes #26372

app/models/system_note_metadata.rb

@@ -2,7 +2,7 @@ class SystemNoteMetadata < ActiveRecord::Base
   ICON_TYPES = %w[
     commit description merge confidential visible label assignee cross_reference
     title time_tracking branch milestone discussion task moved opened closed merged
-    outdated
+    outdated duplicate
   ].freeze
   validates :note, presence: true

app/services/issuable_base_service.rb

@@ -46,6 +46,14 @@ class IssuableBaseService < BaseService
     SystemNoteService.change_time_spent(issuable, issuable.project, current_user)
   end
+  def create_issue_duplicate_note(issuable, original_issue)
+    SystemNoteService.mark_duplicate_issue(issuable, issuable.project, current_user, original_issue)
+  end
+
+  def create_cross_reference_note(noteable, mentioner)
+    SystemNoteService.cross_reference(noteable, mentioner, current_user)
+  end
+
   def filter_params(issuable)
     ability_name = :"admin_#{issuable.to_ability_name}"
@@ -58,6 +66,7 @@ class IssuableBaseService < BaseService
       params.delete(:assignee_ids)
       params.delete(:assignee_id)
       params.delete(:due_date)
+      params.delete(:original_issue_id)
     end
     filter_assignee(issuable)
@@ -209,6 +218,7 @@ class IssuableBaseService < BaseService
     change_state(issuable)
     change_subscription(issuable)
     change_todo(issuable)
+    change_issue_duplicate(issuable)
     toggle_award(issuable)
     filter_params(issuable)
     old_labels = issuable.labels.to_a
@@ -291,6 +301,18 @@ class IssuableBaseService < BaseService
     end
   end
+  def change_issue_duplicate(issuable)
+    original_issue_id = params.delete(:original_issue_id)
+    return if original_issue_id.nil?
+
+    original_issue = IssuesFinder.new(current_user).find(original_issue_id)
+    if original_issue.present?
+      create_issue_duplicate_note(issuable, original_issue)
+      close_service.new(project, current_user, {}).execute(issuable)
+      create_cross_reference_note(original_issue, issuable)
+    end
+  end
+
   def toggle_award(issuable)
     award = params.delete(:emoji_award)
     if award

app/services/quick_actions/interpret_service.rb

@@ -471,6 +471,20 @@ module QuickActions
       end
     end
+    desc 'Mark this issue as a duplicate of another issue'
+    params '#issue'
+    condition do
+      issuable.is_a?(Issue) &&
+        issuable.persisted? &&
+        current_user.can?(:"update_#{issuable.to_ability_name}", issuable)
+    end
+    command :duplicate do |duplicate_param|
+      original_issue = extract_references(duplicate_param, :issue).first
+      if original_issue.present? && original_issue != issuable
+        @updates[:original_issue_id] = original_issue.id
+      end
+    end
+
     def extract_users(params)
       return [] if params.nil?

app/services/system_note_service.rb

@@ -552,6 +552,25 @@ module SystemNoteService
     create_note(NoteSummary.new(noteable, project, author, body, action: 'moved'))
   end
+  # Called when a Notable has been marked as a duplicate of another Issue
+  #
+  # noteable   - Noteable object
+  # project    - Project owning noteable
+  # author     - User performing the change
+  # original_issue - Issue that this is a duplicate of
+  #
+  # Example Note text:
+  #
+  #   "marked this issue as a duplicate of #1234"
+  #
+  #   "marked this issue as a duplicate of other_project#5678"
+  #
+  # Returns the created Note object
+  def mark_duplicate_issue(noteable, project, author, original_issue)
+    body = "marked this issue as a duplicate of #{original_issue.to_reference(project)}"
+    create_note(NoteSummary.new(noteable, project, author, body, action: 'duplicate'))
+  end
+
   private
   def notes_for_mentioner(mentioner, noteable, notes)

changelogs/unreleased/26372-duplicate-issue-slash-command.yml

+---
+title: Added /duplicate slash command to close a duplicate issue
+merge_request:
+author: Ryan Scott

doc/user/project/quick_actions.md

@@ -37,3 +37,4 @@ do.
 | `/target_branch <Branch Name>` | Set target branch for current merge request |
 | `/award :emoji:`  | Toggle award for :emoji: |
 | `/board_move ~column`      | Move issue to column on the board |
+| `/duplicate #issue`        | Closes this issue and marks it as a duplicate of another issue |

spec/features/issues/user_uses_slash_commands_spec.rb

@@ -134,5 +134,46 @@ feature 'Issues > User uses quick actions', feature: true, js: true do
         expect(page).not_to have_content '/wip'
       end
     end
+
+    describe 'mark issue as duplicate' do
+      let(:issue) { create(:issue, project: project) }
+      let(:original_issue) { create(:issue, project: project) }
+
+      context 'when the current user can update issues' do
+        it 'does not create a note, and marks the issue as a duplicate' do
+          write_note("/duplicate ##{original_issue.to_reference}")
+
+          expect(page).not_to have_content "/duplicate #{original_issue.to_reference}"
+          expect(page).to have_content 'Commands applied'
+          expect(page).to have_content "marked this issue as a duplicate of #{original_issue.to_reference}"
+
+          issue.reload
+
+          expect(issue.closed?).to be_truthy
+        end
+      end
+
+      context 'when the current user cannot update the issue' do
+        let(:guest) { create(:user) }
+        before do
+          project.team << [guest, :guest]
+          logout
+          login_with(guest)
+          visit namespace_project_issue_path(project.namespace, project, issue)
+        end
+
+        it 'does not create a note, and does not mark the issue as a duplicate' do
+          write_note("/duplicate ##{original_issue.to_reference}")
+
+          expect(page).to have_content "/duplicate ##{original_issue.to_reference}"
+          expect(page).not_to have_content 'Commands applied'
+          expect(page).not_to have_content "marked this issue as a duplicate of #{original_issue.to_reference}"
+
+          issue.reload
+
+          expect(issue.closed?).to be_falsey
+        end
+      end
+    end
   end
 end

spec/services/issues/update_service_spec.rb

@@ -491,6 +491,62 @@ describe Issues::UpdateService, services: true do
       include_examples 'updating mentions', Issues::UpdateService
     end
+    context 'duplicate issue' do
+      let(:issues_finder) { spy(:issues_finder) }
+      let(:close_service) { spy(:close_service) }
+
+      before do
+        allow(IssuesFinder).to receive(:new).and_return(issues_finder)
+        allow(Issues::CloseService).to receive(:new).and_return(close_service)
+        allow(SystemNoteService).to receive(:cross_reference)
+        allow(SystemNoteService).to receive(:mark_duplicate_issue)
+      end
+
+      context 'invalid original_issue_id' do
+        let(:original_issue_id) { double }
+        before { update_issue({ original_issue_id: original_issue_id }) }
+
+        it 'finds the root issue' do
+          expect(issues_finder).to have_received(:find).with(original_issue_id)
+        end
+
+        it 'does not close the issue' do
+          expect(close_service).not_to have_received(:execute)
+        end
+
+        it 'does not create system notes' do
+          expect(SystemNoteService).not_to have_received(:cross_reference)
+          expect(SystemNoteService).not_to have_received(:mark_duplicate_issue)
+        end
+      end
+
+      context 'valid original_issue_id' do
+        let(:original_issue) { create(:issue, project: project) }
+        let(:original_issue_id) { double }
+
+        before do
+          allow(issues_finder).to receive(:find).and_return(original_issue)
+          update_issue({ original_issue_id: original_issue_id })
+        end
+
+        it 'finds the root issue' do
+          expect(issues_finder).to have_received(:find).with(original_issue_id)
+        end
+
+        it 'closes the issue' do
+          expect(close_service).to have_received(:execute).with(issue)
+        end
+
+        it 'creates a system note that this issue is a duplicate' do
+          expect(SystemNoteService).to have_received(:mark_duplicate_issue).with(issue, project, user, original_issue)
+        end
+
+        it 'creates a cross reference system note in the other issue' do
+          expect(SystemNoteService).to have_received(:cross_reference).with(original_issue, issue, user)
+        end
+      end
+    end
+
     include_examples 'issuable update service' do
       let(:open_issuable) { issue }
       let(:closed_issuable) { create(:closed_issue, project: project) }

spec/services/quick_actions/interpret_service_spec.rb

@@ -261,6 +261,17 @@ describe QuickActions::InterpretService, services: true do
       end
     end
+    shared_examples 'duplicate command' do
+      let(:issue_duplicate) { create(:issue, project: project) }
+
+      it 'fetches issue and populates original_issue_id if content contains /duplicate issue_reference' do
+        issue_duplicate # populate the issue
+        _, updates = service.execute(content, issuable)
+
+        expect(updates).to eq(original_issue_id: issue_duplicate.id)
+      end
+    end
+
     it_behaves_like 'reopen command' do
       let(:content) { '/reopen' }
       let(:issuable) { issue }
@@ -644,6 +655,26 @@ describe QuickActions::InterpretService, services: true do
       let(:issuable) { issue }
     end
+    it_behaves_like 'duplicate command' do
+      let(:content) { "/duplicate #{issue_duplicate.to_reference}" }
+      let(:issuable) { issue }
+    end
+
+    it_behaves_like 'empty command' do
+      let(:content) { '/duplicate #{issue.to_reference}' }
+      let(:issuable) { issue }
+    end
+
+    it_behaves_like 'empty command' do
+      let(:content) { '/duplicate' }
+      let(:issuable) { issue }
+    end
+
+    it_behaves_like 'empty command' do
+      let(:content) { '/duplicate imaginary#1234' }
+      let(:issuable) { issue }
+    end
+
     context 'when current_user cannot :admin_issue' do
       let(:visitor) { create(:user) }
       let(:issue) { create(:issue, project: project, author: visitor) }
@@ -693,6 +724,11 @@ describe QuickActions::InterpretService, services: true do
         let(:content) { '/remove_due_date' }
         let(:issuable) { issue }
       end
+
+      it_behaves_like 'empty command' do
+        let(:content) { '/duplicate #{issue.to_reference}' }
+        let(:issuable) { issue }
+      end
     end
     context '/award command' do

spec/services/system_note_service_spec.rb

@@ -1101,4 +1101,29 @@ describe SystemNoteService, services: true do
       expect(subject.note).to include(diffs_project_merge_request_url(project, merge_request, diff_id: diff_id, anchor: line_code))
     end
   end
+
+  describe '.mark_duplicate_issue' do
+    subject { described_class.mark_duplicate_issue(noteable, project, author, original_issue) }
+
+    context 'within the same project' do
+      let(:original_issue) { create(:issue, project: project) }
+
+      it_behaves_like 'a system note' do
+        let(:action) { 'duplicate' }
+      end
+
+      it { expect(subject.note).to eq "marked this issue as a duplicate of #{original_issue.to_reference}" }
+    end
+
+    context 'across different projects' do
+      let(:other_project)  { create(:empty_project) }
+      let(:original_issue) { create(:issue, project: other_project) }
+
+      it_behaves_like 'a system note' do
+        let(:action) { 'duplicate' }
+      end
+
+      it { expect(subject.note).to eq "marked this issue as a duplicate of #{original_issue.to_reference(project)}" }
+    end
+  end
 end