[skip ci] Refactor into issue_dropdown_options

app/helpers/form_helper.rb

@@ -15,4 +15,37 @@ module FormHelper
         end
     end
   end
+
+  def issue_dropdown_options(issuable, has_multiple_assignees = true)
+    options = {
+      toggle_class: 'js-user-search js-assignee-search',
+      title: 'Select assignee',
+      filter: true,
+      dropdown_class: 'dropdown-menu-user dropdown-menu-selectable dropdown-menu-assignee',
+      placeholder: 'Search users',
+      data: {
+        first_user: (current_user.username if current_user),
+        null_user: true,
+        current_user: true,
+        project_id: issuable.project.try(:id),
+        field_name: "#{issuable.class.model_name.param_key}[assignee_ids][]",
+        default_label: 'Assignee',
+        'max-select': 1,
+        'dropdown-header': 'Assignee',
+      }
+    }
+
+    if has_multiple_assignees
+      options[:toggle_class] += ' js-multiselect js-save-user-data'
+      options[:title] = 'Select assignee(s)'
+      options[:data][:multi_select] = true
+      options[:data][:'input-meta'] = 'name'
+      options[:data][:'always-show-selectbox'] = true
+      options[:data][:current_user_info] = current_user.to_json(only: [:id, :name])
+      options[:data][:'dropdown-header'] = 'Assignee(s)'
+      options[:data].delete(:'max-select')
+    end
+
+    options
+  end
 end

app/views/shared/issuable/form/_metadata.html.haml

@@ -17,18 +17,7 @@
             - issuable.assignees.each do |assignee|
               = hidden_field_tag "#{issuable.to_ability_name}[assignee_ids][]", assignee.id, id: nil, data: { meta: assignee.name }
 
-            - options = { toggle_class: "js-user-search js-assignee-search", title: 'Select assignee', filter: true, dropdown_class: "dropdown-menu-user dropdown-menu-selectable dropdown-menu-assignee",
-              placeholder: "Search users", data: { first_user: (current_user.username if current_user), null_user: true, current_user: true, project_id: issuable.project.try(:id), field_name: "#{issuable.class.model_name.param_key}[assignee_ids][]", default_label: "Assignee"} }
-
-            - options[:toggle_class] += ' js-multiselect js-save-user-data'
-            - options[:title] = 'Select assignee(s)'
-            - options[:data][:multi_select] = true
-            - options[:data]['input-meta'] = 'name'
-            - options[:data]['dropdown-header'] = 'Assignee(s)'
-            - options[:data]['always-show-selectbox'] = true
-            - options[:data][:current_user_info] = current_user.to_json(only: [:id, :name])
-
-            = dropdown_tag(users_dropdown_label(issuable.assignees), options: options)
+            = dropdown_tag(users_dropdown_label(issuable.assignees), options: issue_dropdown_options(issuable, true))
           = link_to 'Assign to me', '#', class: "assign-to-me-link #{'hide' if issuable.assignees.include?(current_user)}"
       - else
         = form.label :assignee_id, "Assignee", class: "control-label #{"col-lg-4" if has_due_date}"