Refactor template selector in issuable form

Signed-off-by: Rémy Coutable <remy@rymai.me>

app/helpers/blob_helper.rb

@@ -179,33 +179,6 @@ module BlobHelper
     }
   end
 
-  def selected_template(issuable)
-    templates = issuable_templates(issuable)
-    params[:issuable_template] if templates.include?(params[:issuable_template])
-  end
-
-  def can_add_template?(issuable)
-    names = issuable_templates(issuable)
-    names.empty? && can?(current_user, :push_code, @project) && !@project.private?
-  end
-
-  def merge_request_template_names
-    @merge_request_templates ||= Gitlab::Template::MergeRequestTemplate.dropdown_names(ref_project)
-  end
-
-  def issue_template_names
-    @issue_templates ||= Gitlab::Template::IssueTemplate.dropdown_names(ref_project)
-  end
-
-  def issuable_templates(issuable)
-    @issuable_templates ||=
-      if issuable.is_a?(Issue)
-        issue_template_names
-      elsif issuable.is_a?(MergeRequest)
-        merge_request_template_names
-      end
-  end
-
   def ref_project
     @ref_project ||= @target_project || @project
   end

app/helpers/issuables_helper.rb

@@ -30,6 +30,33 @@ module IssuablesHelper
     end
   end
 
+  def can_add_template?(issuable)
+    names = issuable_templates(issuable)
+    names.empty? && can?(current_user, :push_code, @project) && !@project.private?
+  end
+
+  def template_dropdown_tag(issuable, &block)
+    title = selected_template(issuable) || "Choose a template"
+    options = {
+      toggle_class: 'js-issuable-selector',
+      title: title,
+      filter: true,
+      placeholder: 'Filter',
+      footer_content: true,
+      data: {
+        data: issuable_templates(issuable),
+        field_name: 'issuable_template',
+        selected: selected_template(issuable),
+        project_path: ref_project.path,
+        namespace_path: ref_project.namespace.path
+      }
+    }
+
+    dropdown_tag(title, options: options) do
+      capture(&block)
+    end
+  end
+
   def user_dropdown_label(user_id, default_label)
     return default_label if user_id.nil?
     return "Unassigned" if user_id == "0"
@@ -153,4 +180,28 @@ module IssuablesHelper
 
     hexdigest(['issuables_count', issuable_type, opts.sort].flatten.join('-'))
   end
+
+  def issuable_templates(issuable)
+    @issuable_templates ||=
+      case issuable
+      when Issue
+        issue_template_names
+      when MergeRequest
+        merge_request_template_names
+      else
+        raise 'Unknown issuable type!'
+      end
+  end
+
+  def merge_request_template_names
+    @merge_request_templates ||= Gitlab::Template::MergeRequestTemplate.dropdown_names(ref_project)
+  end
+
+  def issue_template_names
+    @issue_templates ||= Gitlab::Template::IssueTemplate.dropdown_names(ref_project)
+  end
+
+  def selected_template(issuable)
+    params[:issuable_template] if issuable_templates(issuable).include?(params[:issuable_template])
+  end
 end

app/views/shared/issuable/_form.html.haml

 - project = @target_project || @project
+
 = form_errors(issuable)
 
 - if @conflict
@@ -11,23 +12,9 @@
 .form-group
   = f.label :title, class: 'control-label'
 
-  - issuable_template_names = issuable_templates(issuable)
-
-  - if issuable_template_names.any?
-    .col-sm-3.col-lg-2
-      .js-issuable-selector-wrap{ data: { issuable_type: issuable.class.to_s.underscore.downcase } }
-        - title = selected_template(issuable) || "Choose a template"
-
-        = dropdown_tag(title, options: { toggle_class: 'js-issuable-selector',
-          title: title, filter: true, placeholder: 'Filter', footer_content: true,
-          data: { data: issuable_template_names, field_name: 'issuable_template', selected: selected_template(issuable), project_path: ref_project.path, namespace_path: ref_project.namespace.path } } ) do
-          %ul.dropdown-footer-list
-            %li
-              %a.no-template
-                No template
-              %a.reset-template
-                Reset template
-  %div{ class: issuable_template_names.any? ? 'col-sm-7 col-lg-8' : 'col-sm-10' }
+  = render 'shared/issuable/form/template_selector', issuable: issuable
+
+  %div{ class: issuable_templates(issuable).any? ? 'col-sm-7 col-lg-8' : 'col-sm-10' }
     = f.text_field :title, maxlength: 255, autofocus: true, autocomplete: 'off',
         class: 'form-control pad', required: true
 

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

+- issuable = local_assigns.fetch(:issuable, nil)
+
+- return unless issuable && issuable_templates(issuable).any?
+
+.col-sm-3.col-lg-2
+  .js-issuable-selector-wrap{ data: { issuable_type: issuable.to_ability_name } }
+    = template_dropdown_tag(issuable) do
+      %ul.dropdown-footer-list
+        %li
+          %a.no-template
+            No template
+          %a.reset-template
+            Reset template