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

3 files changed, 55 insertions, 0 deletions

diff --git a/app/services/issuable_base_service.rb b/app/services/issuable_base_service.rb
index 9078b1f0983..c7e646222bb 100644
--- a/app/services/issuable_base_service.rb
+++ b/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
diff --git a/app/services/quick_actions/interpret_service.rb b/app/services/quick_actions/interpret_service.rb
index 6f82159e6c7..3eecf0b5545 100644
--- a/app/services/quick_actions/interpret_service.rb
+++ b/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?
 
diff --git a/app/services/system_note_service.rb b/app/services/system_note_service.rb
index da0f21d449a..2e5e904c43d 100644
--- a/app/services/system_note_service.rb
+++ b/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)