Rolldown issue and merge request templates to projects in the group

Description templates are a variation of file templates, however
description templates were only visible at the project level in which
those were defined.

This implements the ability to inherit description templates from
projects that define description templates and are set as template
repository at group level.

This will allow to display both inherited description templates
from parent group(s) and instance down to project's own own
description templates

Edit issue is using a different FE(vue app) to be redered vs new issue
form. Update templates controller to return the right templates and in
corresponding format, i.e. hash instead of array.

Fix the edge case when templtes in different groups have the same name,
so that it would be correctly resolved to the correct template.

app/assets/javascripts/incidents_settings/constants.js

@@ -51,7 +51,7 @@ export const NO_ISSUE_TEMPLATE_SELECTED = { key: '', name: __('No template selec
 export const TAKING_INCIDENT_ACTION_DOCS_LINK =
   '/help/operations/metrics/alerts#trigger-actions-from-alerts';
 export const ISSUE_TEMPLATES_DOCS_LINK =
-  '/help/user/project/description_templates#creating-issue-templates';
+  '/help/user/project/description_templates#create-an-issue-template';
 
 /* PagerDuty integration settings constants */
 

app/assets/javascripts/issue_show/components/app.vue

@@ -307,7 +307,7 @@ export default {
         });
     },
 
-    updateAndShowForm(templates = []) {
+    updateAndShowForm(templates = {}) {
       if (!this.showForm) {
         this.showForm = true;
         this.store.setFormState({

app/assets/javascripts/issue_show/components/fields/description_template.vue

@@ -13,9 +13,9 @@ export default {
       required: true,
     },
     issuableTemplates: {
-      type: Array,
+      type: [Object, Array],
       required: false,
-      default: () => [],
+      default: () => {},
     },
     projectPath: {
       type: String,

app/assets/javascripts/issue_show/components/form.vue

@@ -26,9 +26,9 @@ export default {
       required: true,
     },
     issuableTemplates: {
-      type: Array,
+      type: [Object, Array],
       required: false,
-      default: () => [],
+      default: () => {},
     },
     issuableType: {
       type: String,
@@ -72,7 +72,7 @@ export default {
   },
   computed: {
     hasIssuableTemplates() {
-      return this.issuableTemplates.length;
+      return Object.values(Object(this.issuableTemplates)).length;
     },
     showLockedWarning() {
       return this.formState.lockedWarningVisible && !this.formState.updateLoading;

app/assets/javascripts/issue_show/stores/index.js

@@ -11,7 +11,7 @@ export default class Store {
       lockedWarningVisible: false,
       updateLoading: false,
       lock_version: 0,
-      issuableTemplates: [],
+      issuableTemplates: {},
     };
   }
 

app/controllers/projects/templates_controller.rb

@@ -25,7 +25,7 @@ class Projects::TemplatesController < Projects::ApplicationController
 
   def names
     respond_to do |format|
-      format.json { render json: TemplateFinder.all_template_names_array(project, params[:template_type].to_s.pluralize) }
+      format.json { render json: TemplateFinder.all_template_names_hash_or_array(project, params[:template_type].to_s) }
     end
   end
 

app/finders/template_finder.rb

@@ -22,16 +22,26 @@ class TemplateFinder
       end
     end
 
+    # This is temporary and will be removed once we introduce group level inherited templates and
+    # remove the inherited_issuable_templates FF
+    def all_template_names_hash_or_array(project, issuable_type)
+      if project.inherited_issuable_templates_enabled?
+        all_template_names(project, issuable_type.pluralize)
+      else
+        all_template_names_array(project, issuable_type.pluralize)
+      end
+    end
+
     def all_template_names(project, type)
       return {} if !VENDORED_TEMPLATES.key?(type.to_s) && type.to_s != 'licenses'
 
       build(type, project).template_names
     end
 
-    # This is issues and merge requests description templates only.
-    # This will be removed once we introduce group level inherited templates
+    # This is for issues and merge requests description templates only.
+    # This will be removed once we introduce group level inherited templates and remove the inherited_issuable_templates FF
     def all_template_names_array(project, type)
-      all_template_names(project, type).values.flatten.uniq
+      all_template_names(project, type).values.flatten.select { |tmpl| tmpl[:project_id] == project.id }.compact.uniq
     end
   end
 

app/helpers/issuables_description_templates_helper.rb

@@ -5,7 +5,8 @@ module IssuablesDescriptionTemplatesHelper
   include GitlabRoutingHelper
 
   def template_dropdown_tag(issuable, &block)
-    title = selected_template(issuable) || "Choose a template"
+    selected_template = selected_template(issuable)
+    title = selected_template || "Choose a template"
     options = {
       toggle_class: 'js-issuable-selector',
       title: title,
@@ -15,7 +16,7 @@ module IssuablesDescriptionTemplatesHelper
       data: {
         data: issuable_templates(ref_project, issuable.to_ability_name),
         field_name: 'issuable_template',
-        selected: selected_template(issuable),
+        selected: selected_template,
         project_id: ref_project.id
       }
     }
@@ -28,15 +29,21 @@ module IssuablesDescriptionTemplatesHelper
   def issuable_templates(project, issuable_type)
     @template_types ||= {}
     @template_types[project.id] ||= {}
-    @template_types[project.id][issuable_type] ||= TemplateFinder.all_template_names_array(project, issuable_type.pluralize)
+    @template_types[project.id][issuable_type] ||= TemplateFinder.all_template_names_hash_or_array(project, issuable_type)
   end
 
   def issuable_templates_names(issuable)
-    issuable_templates(ref_project, issuable.to_ability_name).map { |template| template[:name] }
+    all_templates = issuable_templates(ref_project, issuable.to_ability_name)
+
+    if ref_project.inherited_issuable_templates_enabled?
+      all_templates.values.flatten.map { |tpl| tpl[:name] if tpl[:project_id] == ref_project.id }.compact.uniq
+    else
+      all_templates.map { |template| template[:name] }
+    end
   end
 
   def selected_template(issuable)
-    params[:issuable_template] if issuable_templates(ref_project, issuable.to_ability_name).any? { |template| template[:name] == params[:issuable_template] }
+    params[:issuable_template] if issuable_templates_names(issuable).any? { |tmpl_name| tmpl_name == params[:issuable_template] }
   end
 
   def template_names_path(parent, issuable)

app/models/project.rb

@@ -2532,6 +2532,10 @@ class Project < ApplicationRecord
     Projects::GitGarbageCollectWorker
   end
 
+  def inherited_issuable_templates_enabled?
+    Feature.enabled?(:inherited_issuable_templates, self, default_enabled: :yaml)
+  end
+
   private
 
   def find_service(services, name)

config/feature_flags/development/inherited_issuable_templates.yml

+---
+name: inherited_issuable_templates
+introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/52360
+rollout_issue_url: https://gitlab.com/gitlab-org/gitlab/-/issues/321247
+milestone: '13.9'
+type: development
+group: group::project management
+default_enabled: false

doc/api/project_templates.md

@@ -100,7 +100,7 @@ GET /projects/:id/templates/:type/:name
 | Attribute  | Type   | Required | Description |
 | ---------- | ------ | -------- | ----------- |
 | `id`      | integer / string | yes      | The ID or [URL-encoded path of the project](README.md#namespaced-path-encoding) |
-| `type`     | string | yes| The type `(dockerfiles|gitignores|gitlab_ci_ymls|licenses|issues|merge_requests)` of the template |
+| `type`     | string | yes| The type of the template. One of: `dockerfiles`, `gitignores`, `gitlab_ci_ymls`, `licenses`, `issues`, or `merge_requests`. |
 | `name`     | string | yes      | The key of the template, as obtained from the collection endpoint |
 | `source_template_project_id`   | integer | no      | The project ID where a given template is being stored. This is useful when multiple templates from different projects have the same name. If multiple templates have the same name, the match from `closest ancestor` is returned if `source_template_project_id` is not specified |
 | `project`  | string | no       | The project name to use when expanding placeholders in the template. Only affects licenses |

doc/development/features_inside_dot_gitlab.md

@@ -10,8 +10,8 @@ We have implemented standard features that depend on configuration files in the
 When implementing new features, please refer to these existing features to avoid conflicts:
 
 - [Custom Dashboards](../operations/metrics/dashboards/index.md#add-a-new-dashboard-to-your-project): `.gitlab/dashboards/`.
-- [Issue Templates](../user/project/description_templates.md#creating-issue-templates): `.gitlab/issue_templates/`.
-- [Merge Request Templates](../user/project/description_templates.md#creating-merge-request-templates): `.gitlab/merge_request_templates/`.
+- [Issue Templates](../user/project/description_templates.md#create-an-issue-template): `.gitlab/issue_templates/`.
+- [Merge Request Templates](../user/project/description_templates.md#create-a-merge-request-template): `.gitlab/merge_request_templates/`.
 - [GitLab Kubernetes Agents](https://gitlab.com/gitlab-org/cluster-integration/gitlab-agent/-/blob/master/doc/configuration_repository.md#layout): `.gitlab/agents/`.
 - [CODEOWNERS](../user/project/code_owners.md#how-to-set-up-code-owners): `.gitlab/CODEOWNERS`.
 - [Route Maps](../ci/review_apps/#route-maps): `.gitlab/route-map.yml`.

doc/operations/incident_management/incidents.md

@@ -54,7 +54,7 @@ With Maintainer or higher [permissions](../../user/permissions.md), you can enab
 1. Navigate to **Settings > Operations > Incidents** and expand **Incidents**.
 1. Check the **Create an incident** checkbox.
 1. To customize the incident, select an
-   [issue template](../../user/project/description_templates.md#creating-issue-templates).
+   [issue template](../../user/project/description_templates.md#create-an-issue-template).
 1. To send [an email notification](paging.md#email-notifications) to users
    with [Developer permissions](../../user/permissions.md), select
    **Send a separate email notification to Developers**. Email notifications are

doc/subscriptions/bronze_starter.md

@@ -20,7 +20,7 @@ the tiers are no longer mentioned in GitLab documentation:
   [per-group charts](../user/project/milestones/index.md#group-burndown-charts)
 - [Code owners](../user/project/code_owners.md)
 - Description templates:
-  - [Setting a default template for merge requests and issues](../user/project/description_templates.md#setting-a-default-template-for-merge-requests-and-issues)
+  - [Setting a default template for merge requests and issues](../user/project/description_templates.md#set-a-default-template-for-merge-requests-and-issues)
 - [Email from GitLab](../tools/email.md)
 - Groups:
   - [Creating group memberships via CN](../user/group/index.md#creating-group-links-via-cn)

doc/user/project/description_templates.md

@@ -37,10 +37,10 @@ To learn how to create templates for various file types in groups, visit
   images guidelines, link to the related issue, reviewer name, and so on.
 - You can also create issues and merge request templates for different
   stages of your workflow, for example, feature proposal, feature improvement, or a bug report.
-- You can use an [issue description template](#creating-issue-templates) as a
+- You can use an [issue description template](#create-an-issue-template) as a
   [Service Desk email template](service_desk.md#new-service-desk-issues).
 
-## Creating issue templates
+## Create an issue template
 
 Create a new Markdown (`.md`) file inside the `.gitlab/issue_templates/`
 directory in your repository. Commit and push to your default branch.
@@ -65,13 +65,13 @@ To create the `.gitlab/issue_templates` directory:
 To check if this has worked correctly, [create a new issue](issues/managing_issues.md#create-a-new-issue)
 and see if you can choose a description template.
 
-## Creating merge request templates
+## Create a merge request template
 
 Similarly to issue templates, create a new Markdown (`.md`) file inside the
 `.gitlab/merge_request_templates/` directory in your repository. Commit and
 push to your default branch.
 
-## Using the templates
+## Use the templates
 
 Let's take for example that you've created the file `.gitlab/issue_templates/Bug.md`.
 This enables the `Bug` dropdown option when creating or editing issues. When
@@ -85,9 +85,45 @@ For example: `https://gitlab.com/gitlab-org/gitlab/-/issues/new?issuable_templat
 
 ![Description templates](img/description_templates.png)
 
-## Setting a default template for merge requests and issues **(PREMIUM)**
+### Set an issue and merge request description template at group level **(PREMIUM)**
 
-> - Moved to GitLab Premium in 13.9.
+> - [Introduced](https://gitlab.com/gitlab-org/gitlab/-/merge_requests/52360) in GitLab 13.9.
+> - It's [deployed behind a feature flag](../feature_flags.md), disabled by default.
+> - It's disabled by default on GitLab.com.
+> - To use it in GitLab self-managed instances, ask a GitLab administrator to
+    [enable it](#enable-or-disable-issue-and-merge-request-description-templates-at-group-and-instance-level).
+
+Templates can be useful because you can create a template once and use it multiple times.
+To re-use templates [you've created](../project/description_templates.md#create-an-issue-template):
+
+1. Go to the group's **Settings > General > Templates**.
+1. From the dropdown, select your template project as the template repository at group level.
+
+![Group template settings](../group/img/group_file_template_settings.png)
+
+### Set an issue and merge request description template at instance level **(PREMIUM ONLY)**
+
+> - [Introduced](https://gitlab.com/gitlab-org/gitlab/-/merge_requests/52360) in GitLab 13.9.
+> - It's [deployed behind a feature flag](../feature_flags.md), disabled by default.
+> - It's disabled by default on GitLab.com.
+> - To use it in GitLab self-managed instances, ask a GitLab administrator to
+    [enable it](#enable-or-disable-issue-and-merge-request-description-templates-at-group-and-instance-level).
+
+Similar to group templates, issue and merge request templates can also be set up at the instance level.
+This results in those templates being available in all projects within the instance.
+Only instance administrators can set instance-level templates.
+
+To set the instance-level description template repository:
+
+1. Select the **Admin Area** icon (**{admin}**).
+1. Go to **Settings > Templates**.
+1. From the dropdown, select your template project as the template repository at instance level.
+
+Learn more about [instance template repository](../admin_area/settings/instance_template_repository.md).
+
+![Setting templates in the Admin Area](../admin_area/settings/img/file_template_admin_area.png)
+
+### Set a default template for merge requests and issues **(PREMIUM)**
 
 The visibility of issues or merge requests should be set to either "Everyone
 with access" or "Only Project Members" in your project's **Settings / Visibility, project features, permissions** section, otherwise the
@@ -159,3 +195,28 @@ it's very hard to read otherwise.)
 /cc @project-manager
 /assign @qa-tester
 ```
+
+## Enable or disable issue and merge request description templates at group and instance level
+
+Setting issue and merge request description templates at group and instance levels
+is under development and not ready for production use. It is deployed behind a
+feature flag that is **disabled by default**.
+[GitLab administrators with access to the GitLab Rails console](../../administration/feature_flags.md)
+can enable it.
+
+To enable it:
+
+```ruby
+Feature.enable(:inherited_issuable_templates)
+```
+
+To disable it:
+
+```ruby
+Feature.disable(:inherited_issuable_templates)
+```
+
+The feature flag affects these features:
+
+- Setting a templates project as issue and merge request description templates source at group level.
+- Setting a templates project as issue and merge request description templates source at instance level.

doc/user/project/issues/index.md

@@ -184,7 +184,7 @@ You can then see issue statuses in the [issue list](#issues-list) and the
 
 ## Other Issue actions
 
-- [Create an issue from a template](../../project/description_templates.md#using-the-templates)
+- [Create an issue from a template](../../project/description_templates.md#use-the-templates)
 - [Set a due date](due_dates.md)
 - [Bulk edit issues](../bulk_editing.md) - From the Issues List, select multiple issues
   in order to change their status, assignee, milestone, or labels in bulk.

doc/user/project/service_desk.md

@@ -137,13 +137,13 @@ You can use these placeholders to be automatically replaced in each email:
 
 #### New Service Desk issues
 
-You can select one [issue description template](description_templates.md#creating-issue-templates)
+You can select one [issue description template](description_templates.md#create-an-issue-template)
 **per project** to be appended to every new Service Desk issue's description.
 Issue description templates should reside in your repository's `.gitlab/issue_templates/` directory.
 
 To use a custom issue template with Service Desk, in your project:
 
-1. [Create a description template](description_templates.md#creating-issue-templates)
+1. [Create a description template](description_templates.md#create-an-issue-template)
 1. Go to **Settings > General > Service Desk**.
 1. From the dropdown **Template to append to all Service Desk issues**, select your template.
 

doc/user/project/static_site_editor/index.md

@@ -102,7 +102,7 @@ To edit a file:
    in the bottom-right corner.
 1. When you're done, click **Submit changes...**.
 1. (Optional) Adjust the default title and description of the merge request, to submit
-   with your changes. Alternatively, select a [merge request template](../../../user/project/description_templates.md#creating-merge-request-templates)
+   with your changes. Alternatively, select a [merge request template](../../../user/project/description_templates.md#create-a-merge-request-template)
    from the dropdown menu and edit it accordingly.
 1. Click **Submit changes**.
 1. A new merge request is automatically created and you can assign a colleague for review.

ee/app/finders/ee/template_finder.rb

@@ -17,8 +17,8 @@ module EE
     def initialize(type, project, *args, &blk)
       super
 
-      if CUSTOM_TEMPLATES.key?(type)
-        finder = CUSTOM_TEMPLATES.fetch(type)
+      if custom_templates_mapping.key?(type)
+        finder = custom_templates_mapping.fetch(type)
         @custom_templates = ::Gitlab::CustomFileTemplates.new(finder, project)
       end
     end
@@ -42,5 +42,18 @@ module EE
       # from ancestor group levels
       custom_templates.all_template_names.merge(super)
     end
+
+    # This method is going to be removed once we remove the `inherited_issuable_templates` FF and
+    # issues and merge_requests entries will go into CUSTOM_TEMPLATES
+    def custom_templates_mapping
+      if project&.inherited_issuable_templates_enabled?
+        CUSTOM_TEMPLATES.merge(
+          issues: ::Gitlab::Template::IssueTemplate,
+          merge_requests: ::Gitlab::Template::MergeRequestTemplate
+        )
+      else
+        CUSTOM_TEMPLATES
+      end
+    end
   end
 end

ee/app/views/projects/settings/_default_issue_template.html.haml

@@ -4,7 +4,7 @@
     .settings-header
       %h4.settings-title.js-settings-toggle.js-settings-toggle-trigger-only= _('Default description template for issues')
       %button.gl-button.btn.btn-default.js-settings-toggle{ type: 'button' }= expanded ? _('Collapse') : _('Expand')
-      - link_start = '<a href="%{url}" target="_blank" rel="noopener noreferrer">'.html_safe % { url: help_page_path('user/project/description_templates', anchor: 'setting-a-default-template-for-merge-requests-and-issues') }
+      - link_start = '<a href="%{url}" target="_blank" rel="noopener noreferrer">'.html_safe % { url: help_page_path('user/project/description_templates', anchor: 'set-a-default-template-for-merge-requests-and-issues') }
       %p#issue-settings-default-template-label= _('Set a default description template to be used for new issues. %{link_start}What are description templates?%{link_end}').html_safe % { link_start: link_start, link_end: '</a>'.html_safe }
 
     .settings-content

ee/lib/gitlab/custom_file_templates.rb

@@ -116,7 +116,7 @@ module Gitlab
     def translate(template, project, category:)
       return unless template
 
-      template.category = category
+      template.category = category if category
 
       # License templates require special handling as the "vendored" licenses
       # are actually in a gem, not on disk like the rest of the templates. So,

ee/spec/features/projects/settings/ee/service_desk_setting_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe 'Service Desk Setting', :js, :clean_gitlab_redis_cache do
+  let_it_be(:issuable_project_template_files) do
+    {
+      '.gitlab/issue_templates/project-issue-bar.md' => 'Project Issue Template Bar',
+      '.gitlab/issue_templates/project-issue-foo.md' => 'Project Issue Template Foo'
+    }
+  end
+
+  let_it_be(:issuable_group_template_files) do
+    {
+      '.gitlab/issue_templates/group-issue-bar.md' => 'Group Issue Template Bar',
+      '.gitlab/issue_templates/group-issue-foo.md' => 'Group Issue Template Foo'
+    }
+  end
+
+  let_it_be_with_reload(:group) { create(:group)}
+  let_it_be_with_reload(:project) { create(:project, :custom_repo, group: group, files: issuable_project_template_files) }
+  let_it_be(:group_template_repo) { create(:project, :custom_repo, group: group, files: issuable_group_template_files) }
+  let_it_be(:user) { create(:user) }
+  let_it_be(:presenter) { project.present(current_user: user) }
+
+  before do
+    stub_licensed_features(custom_file_templates_for_namespace: true, custom_file_templates: true)
+
+    project.add_maintainer(user)
+    sign_in(user)
+
+    allow(::Gitlab::IncomingEmail).to receive(:enabled?) { true }
+    allow(::Gitlab::IncomingEmail).to receive(:supports_wildcard?) { true }
+
+    allow(::Gitlab::ServiceDeskEmail).to receive(:enabled?) { true }
+    allow(::Gitlab::ServiceDeskEmail).to receive(:address_for_key) { 'address-suffix@example.com' }
+
+    allow_next_instance_of(Project) do |proj_instance|
+      expect(proj_instance).to receive(:present).with(current_user: user).and_return(presenter)
+    end
+
+    group.update_columns(file_template_project_id: group_template_repo.id)
+  end
+
+  context 'when inherited_issuable_templates enabled' do
+    before do
+      stub_feature_flags(inherited_issuable_templates: true)
+      visit edit_project_path(project)
+    end
+
+    it_behaves_like 'issue description templates from current project only'
+  end
+
+  context 'when inherited_issuable_templates disabled' do
+    before do
+      stub_feature_flags(inherited_issuable_templates: false)
+      visit edit_project_path(project)
+    end
+
+    it_behaves_like 'issue description templates from current project only'
+  end
+end

ee/spec/finders/template_finder_spec.rb

@@ -20,6 +20,8 @@ RSpec.describe TemplateFinder do
       :dockerfiles    | ::Gitlab::Template::CustomDockerfileTemplate
       :gitignores     | ::Gitlab::Template::CustomGitignoreTemplate
       :gitlab_ci_ymls | ::Gitlab::Template::CustomGitlabCiYmlTemplate
+      :issues         | ::Gitlab::Template::IssueTemplate
+      :merge_requests | ::Gitlab::Template::MergeRequestTemplate
     end
 
     with_them do

ee/spec/helpers/ee/issuables_description_templates_helper_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe IssuablesDescriptionTemplatesHelper do
+  include_context 'project issuable templates context'
+
+  describe '#issuable_templates' do
+    context 'when project parent group has a file template project' do
+      let_it_be(:user) { create(:user) }
+      let_it_be_with_reload(:parent_group) { create(:group) }
+      let_it_be_with_reload(:group) { create(:group, parent: parent_group) }
+      let_it_be_with_reload(:project) { create(:project, :custom_repo, group: group, files: issuable_template_files) }
+      let_it_be(:file_template_project) { create(:project, :custom_repo, group: parent_group, files: issuable_template_files) }
+      let_it_be(:group_member) { create(:group_member, :developer, group: parent_group, user: user) }
+      let_it_be(:inherited_from) { file_template_project }
+
+      before do
+        stub_licensed_features(custom_file_templates_for_namespace: true)
+
+        parent_group.update_columns(file_template_project_id: file_template_project.id)
+      end
+
+      it_behaves_like 'project issuable templates'
+    end
+  end
+end

ee/spec/lib/gitlab/template/custom_templates_spec.rb

@@ -27,20 +27,34 @@ RSpec.describe "Custom file template classes" do
     'Dockerfile/category/baz.txt' => 'CustomDockerfileTemplate category baz',
     'gitignore/category/baz.txt'  => 'CustomGitignoreTemplate category baz',
     'gitlab-ci/category/baz.yml'  => 'CustomGitlabCiYmlTemplate category baz',
-    'LICENSE/category/baz.txt'    => 'CustomLicenseTemplate category baz'
+    'LICENSE/category/baz.txt'    => 'CustomLicenseTemplate category baz',
+
+    '.gitlab/issue_templates/bar.md' => 'IssueTemplate Bar',
+    '.gitlab/issue_templates/foo.md' => 'IssueTemplate Foo',
+    '.gitlab/issue_templates/bad.txt' => 'IssueTemplate Bad',
+    '.gitlab/issue_templates/baz.xyz' => 'IssueTemplate Baz',
+
+    '.gitlab/merge_request_templates/bar.md' => 'MergeRequestTemplate Bar',
+    '.gitlab/merge_request_templates/foo.md' => 'MergeRequestTemplate Foo',
+    '.gitlab/merge_request_templates/bad.txt' => 'MergeRequestTemplate Bad',
+    '.gitlab/merge_request_templates/baz.xyz' => 'MergeRequestTemplate Baz'
   }
 
   let_it_be(:project) { create(:project, :custom_repo, files: files) }
 
-  [
-    ::Gitlab::Template::CustomDockerfileTemplate,
-    ::Gitlab::Template::CustomGitignoreTemplate,
-    ::Gitlab::Template::CustomGitlabCiYmlTemplate,
-    ::Gitlab::Template::CustomLicenseTemplate,
-    ::Gitlab::Template::CustomMetricsDashboardYmlTemplate
-  ].each do |template_class|
-    describe template_class do
-      let(:name) { template_class.name.demodulize }
+  custom_templates = [
+    { class_name: ::Gitlab::Template::CustomDockerfileTemplate, category: 'Custom' },
+    { class_name: ::Gitlab::Template::CustomGitignoreTemplate, category: 'Custom' },
+    { class_name: ::Gitlab::Template::CustomGitlabCiYmlTemplate, category: 'Custom' },
+    { class_name: ::Gitlab::Template::CustomLicenseTemplate, category: 'Custom' },
+    { class_name: ::Gitlab::Template::CustomMetricsDashboardYmlTemplate, category: 'Custom' },
+    { class_name: ::Gitlab::Template::IssueTemplate, category: 'Project Templates' },
+    { class_name: ::Gitlab::Template::MergeRequestTemplate, category: 'Project Templates' }
+  ].freeze
+
+  custom_templates.each do |template_class|
+    describe template_class[:class_name] do
+      let(:name) { template_class[:class_name].name.demodulize }
 
       describe '.all' do
         it 'returns all valid templates' do
@@ -48,7 +62,7 @@ RSpec.describe "Custom file template classes" do
 
           aggregate_failures do
             expect(found.map(&:name)).to contain_exactly('foo', 'bar')
-            expect(found.map(&:category).uniq).to contain_exactly('Custom')
+            expect(found.map(&:category).uniq).to contain_exactly(template_class[:category])
           end
         end
       end

lib/gitlab/template/base_template.rb

@@ -87,11 +87,11 @@ module Gitlab
           raise NotImplementedError
         end
 
-        def by_category(category, project = nil)
+        def by_category(category, project = nil, empty_category_title: nil)
           directory = category_directory(category)
           files = finder(project).list_files_for(directory)
 
-          files.map { |f| new(f, project, category: category) }.sort
+          files.map { |f| new(f, project, category: category.presence || empty_category_title) }.sort
         end
 
         def category_directory(category)

lib/gitlab/template/issue_template.rb

@@ -25,6 +25,10 @@ module Gitlab
           # follow-up issue: https://gitlab.com/gitlab-org/gitlab/-/issues/300279
           project.repository.issue_template_names_by_category
         end
+
+        def by_category(category, project = nil, empty_category_title: nil)
+          super(category, project, empty_category_title: _('Project Templates'))
+        end
       end
     end
   end

lib/gitlab/template/merge_request_template.rb

@@ -25,6 +25,10 @@ module Gitlab
           # follow-up issue: https://gitlab.com/gitlab-org/gitlab/-/issues/300279
           project.repository.merge_request_template_names_by_category
         end
+
+        def by_category(category, project = nil, empty_category_title: nil)
+          super(category, project, empty_category_title: _('Project Templates'))
+        end
       end
     end
   end

locale/gitlab.pot

@@ -22961,6 +22961,9 @@ msgstr ""
 msgid "Project ID"
 msgstr ""
 
+msgid "Project Templates"
+msgstr ""
+
 msgid "Project URL"
 msgstr ""
 

spec/controllers/projects/templates_controller_spec.rb

@@ -160,13 +160,28 @@ RSpec.describe Projects::TemplatesController do
     end
 
     shared_examples 'template names request' do
-      it 'returns the template names' do
-        get(:names, params: { namespace_id: project.namespace, template_type: template_type, project_id: project }, format: :json)
+      context 'when feature flag enabled' do
+        it 'returns the template names', :aggregate_failures do
+          get(:names, params: { namespace_id: project.namespace, template_type: template_type, project_id: project }, format: :json)
 
-        expect(response).to have_gitlab_http_status(:ok)
-        expect(json_response.size).to eq(2)
-        expect(json_response.size).to eq(2)
-        expect(json_response.map { |x| x.slice('name') }).to match(expected_template_names)
+          expect(response).to have_gitlab_http_status(:ok)
+          expect(json_response['Project Templates'].size).to eq(2)
+          expect(json_response['Project Templates'].map { |x| x.slice('name') }).to match(expected_template_names)
+        end
+      end
+
+      context 'when feature flag disabled' do
+        before do
+          stub_feature_flags(inherited_issuable_templates: false)
+        end
+
+        it 'returns the template names', :aggregate_failures do
+          get(:names, params: { namespace_id: project.namespace, template_type: template_type, project_id: project }, format: :json)
+
+          expect(response).to have_gitlab_http_status(:ok)
+          expect(json_response.size).to eq(2)
+          expect(json_response.map { |x| x.slice('name') }).to match(expected_template_names)
+        end
       end
 
       it 'fails for user with no access' do

spec/features/projects/settings/service_desk_setting_spec.rb

@@ -2,7 +2,7 @@
 
 require 'spec_helper'
 
-RSpec.describe 'Service Desk Setting', :js do
+RSpec.describe 'Service Desk Setting', :js, :clean_gitlab_redis_cache do
   let(:project) { create(:project_empty_repo, :private, service_desk_enabled: false) }
   let(:presenter) { project.present(current_user: user) }
   let(:user) { create(:user) }
@@ -66,5 +66,48 @@ RSpec.describe 'Service Desk Setting', :js do
 
       expect(find('[data-testid="incoming-email"]').value).to eq('address-suffix@example.com')
     end
+
+    context 'issue description templates' do
+      let_it_be(:issuable_project_template_files) do
+        {
+          '.gitlab/issue_templates/project-issue-bar.md' => 'Project Issue Template Bar',
+          '.gitlab/issue_templates/project-issue-foo.md' => 'Project Issue Template Foo'
+        }
+      end
+
+      let_it_be(:issuable_group_template_files) do
+        {
+          '.gitlab/issue_templates/group-issue-bar.md' => 'Group Issue Template Bar',
+          '.gitlab/issue_templates/group-issue-foo.md' => 'Group Issue Template Foo'
+        }
+      end
+
+      let_it_be_with_reload(:group) { create(:group)}
+      let_it_be_with_reload(:project) { create(:project, :custom_repo, group: group, files: issuable_project_template_files) }
+      let_it_be(:group_template_repo) { create(:project, :custom_repo, group: group, files: issuable_group_template_files) }
+
+      before do
+        stub_licensed_features(custom_file_templates_for_namespace: false, custom_file_templates: false)
+        group.update_columns(file_template_project_id: group_template_repo.id)
+      end
+
+      context 'when inherited_issuable_templates enabled' do
+        before do
+          stub_feature_flags(inherited_issuable_templates: true)
+          visit edit_project_path(project)
+        end
+
+        it_behaves_like 'issue description templates from current project only'
+      end
+
+      context 'when inherited_issuable_templates disabled' do
+        before do
+          stub_feature_flags(inherited_issuable_templates: false)
+          visit edit_project_path(project)
+        end
+
+        it_behaves_like 'issue description templates from current project only'
+      end
+    end
   end
 end

spec/frontend/incidents_settings/components/__snapshots__/alerts_form_spec.js.snap

@@ -35,7 +35,7 @@ exports[`Alert integration settings form default state should match the default
         Incident template (optional)
         
         <gl-link-stub
-          href="/help/user/project/description_templates#creating-issue-templates"
+          href="/help/user/project/description_templates#create-an-issue-template"
           target="_blank"
         >
           <gl-icon-stub

spec/frontend/issue_show/components/app_spec.js

@@ -422,7 +422,18 @@ describe('Issuable output', () => {
       formSpy = jest.spyOn(wrapper.vm, 'updateAndShowForm');
     });
 
-    it('shows the form if template names request is successful', () => {
+    it('shows the form if template names as hash request is successful', () => {
+      const mockData = {
+        test: [{ name: 'test', id: 'test', project_path: '/', namespace_path: '/' }],
+      };
+      mock.onGet('/issuable-templates-path').reply(() => Promise.resolve([200, mockData]));
+
+      return wrapper.vm.requestTemplatesAndShowForm().then(() => {
+        expect(formSpy).toHaveBeenCalledWith(mockData);
+      });
+    });
+
+    it('shows the form if template names as array request is successful', () => {
       const mockData = [{ name: 'test', id: 'test', project_path: '/', namespace_path: '/' }];
       mock.onGet('/issuable-templates-path').reply(() => Promise.resolve([200, mockData]));
 

spec/frontend/issue_show/components/fields/description_template_spec.js

 import Vue from 'vue';
 import descriptionTemplate from '~/issue_show/components/fields/description_template.vue';
 
-describe('Issue description template component', () => {
+describe('Issue description template component with templates as hash', () => {
   let vm;
   let formState;
 
@@ -14,7 +14,9 @@ describe('Issue description template component', () => {
     vm = new Component({
       propsData: {
         formState,
-        issuableTemplates: [{ name: 'test', id: 'test', project_path: '/', namespace_path: '/' }],
+        issuableTemplates: {
+          test: [{ name: 'test', id: 'test', project_path: '/', namespace_path: '/' }],
+        },
         projectId: 1,
         projectPath: '/',
         namespacePath: '/',
@@ -23,9 +25,9 @@ describe('Issue description template component', () => {
     }).$mount();
   });
 
-  it('renders templates as JSON array in data attribute', () => {
+  it('renders templates as JSON hash in data attribute', () => {
     expect(vm.$el.querySelector('.js-issuable-selector').getAttribute('data-data')).toBe(
-      '[{"name":"test","id":"test","project_path":"/","namespace_path":"/"}]',
+      '{"test":[{"name":"test","id":"test","project_path":"/","namespace_path":"/"}]}',
     );
   });
 
@@ -41,3 +43,32 @@ describe('Issue description template component', () => {
     expect(vm.issuableTemplate.editor.getValue()).toBe('testing new template');
   });
 });
+
+describe('Issue description template component with templates as array', () => {
+  let vm;
+  let formState;
+
+  beforeEach(() => {
+    const Component = Vue.extend(descriptionTemplate);
+    formState = {
+      description: 'test',
+    };
+
+    vm = new Component({
+      propsData: {
+        formState,
+        issuableTemplates: [{ name: 'test', id: 'test', project_path: '/', namespace_path: '/' }],
+        projectId: 1,
+        projectPath: '/',
+        namespacePath: '/',
+        projectNamespace: '/',
+      },
+    }).$mount();
+  });
+
+  it('renders templates as JSON array in data attribute', () => {
+    expect(vm.$el.querySelector('.js-issuable-selector').getAttribute('data-data')).toBe(
+      '[{"name":"test","id":"test","project_path":"/","namespace_path":"/"}]',
+    );
+  });
+});

spec/frontend/issue_show/components/form_spec.js

@@ -42,7 +42,7 @@ describe('Inline edit form component', () => {
     expect(vm.$el.querySelector('.js-issuable-selector-wrap')).toBeNull();
   });
 
-  it('renders template selector when templates exists', () => {
+  it('renders template selector when templates as array exists', () => {
     createComponent({
       issuableTemplates: [
         { name: 'test', id: 'test', project_path: 'test', namespace_path: 'test' },
@@ -52,6 +52,16 @@ describe('Inline edit form component', () => {
     expect(vm.$el.querySelector('.js-issuable-selector-wrap')).not.toBeNull();
   });
 
+  it('renders template selector when templates as hash exists', () => {
+    createComponent({
+      issuableTemplates: {
+        test: [{ name: 'test', id: 'test', project_path: 'test', namespace_path: 'test' }],
+      },
+    });
+
+    expect(vm.$el.querySelector('.js-issuable-selector-wrap')).not.toBeNull();
+  });
+
   it('hides locked warning by default', () => {
     createComponent();
 

spec/helpers/issuables_description_templates_helper_spec.rb

@@ -13,22 +13,33 @@ RSpec.describe IssuablesDescriptionTemplatesHelper, :clean_gitlab_redis_cache do
     let_it_be(:group_member) { create(:group_member, :developer, group: parent_group, user: user) }
     let_it_be(:project_member) { create(:project_member, :developer, user: user, project: project) }
 
-    it 'returns empty hash when template type does not exist' do
-      expect(helper.issuable_templates(build(:project), 'non-existent-template-type')).to eq([])
+    context 'when feature flag disabled' do
+      before do
+        stub_feature_flags(inherited_issuable_templates: false)
+      end
+
+      it 'returns empty array when template type does not exist' do
+        expect(helper.issuable_templates(project, 'non-existent-template-type')).to eq([])
+      end
     end
 
-    context 'with cached issuable templates' do
+    context 'when feature flag enabled' do
       before do
-        allow(Gitlab::Template::IssueTemplate).to receive(:template_names).and_return({})
-        allow(Gitlab::Template::MergeRequestTemplate).to receive(:template_names).and_return({})
+        stub_feature_flags(inherited_issuable_templates: true)
+      end
 
-        helper.issuable_templates(project, 'issues')
-        helper.issuable_templates(project, 'merge_request')
+      it 'returns empty hash when template type does not exist' do
+        expect(helper.issuable_templates(build(:project), 'non-existent-template-type')).to eq({})
       end
+    end
 
+    context 'with cached issuable templates' do
       it 'does not call TemplateFinder' do
-        expect(Gitlab::Template::IssueTemplate).not_to receive(:template_names)
-        expect(Gitlab::Template::MergeRequestTemplate).not_to receive(:template_names)
+        expect(Gitlab::Template::IssueTemplate).to receive(:template_names).once.and_call_original
+        expect(Gitlab::Template::MergeRequestTemplate).to receive(:template_names).once.and_call_original
+
+        helper.issuable_templates(project, 'issues')
+        helper.issuable_templates(project, 'merge_request')
         helper.issuable_templates(project, 'issues')
         helper.issuable_templates(project, 'merge_request')
       end
@@ -63,29 +74,78 @@ RSpec.describe IssuablesDescriptionTemplatesHelper, :clean_gitlab_redis_cache do
   end
 
   describe '#issuable_templates_names' do
-    let(:project) { double(Project, id: 21) }
-
-    let(:templates) do
-      [
-        { name: "another_issue_template", id: "another_issue_template", project_id: project.id },
-        { name: "custom_issue_template", id: "custom_issue_template", project_id: project.id }
-      ]
-    end
+    let_it_be(:project) { build(:project) }
 
-    it 'returns project templates only' do
+    before do
       allow(helper).to receive(:ref_project).and_return(project)
       allow(helper).to receive(:issuable_templates).and_return(templates)
+    end
+
+    context 'when feature flag disabled' do
+      let(:templates) do
+        [
+          { name: "another_issue_template", id: "another_issue_template", project_id: project.id },
+          { name: "custom_issue_template", id: "custom_issue_template", project_id: project.id }
+        ]
+      end
 
-      expect(helper.issuable_templates_names(Issue.new)).to eq(%w[another_issue_template custom_issue_template])
+      before do
+        stub_feature_flags(inherited_issuable_templates: false)
+      end
+
+      it 'returns project templates only' do
+        expect(helper.issuable_templates_names(Issue.new)).to eq(%w[another_issue_template custom_issue_template])
+      end
+    end
+
+    context 'when feature flag enabled' do
+      before do
+        stub_feature_flags(inherited_issuable_templates: true)
+      end
+
+      context 'with matching project templates' do
+        let(:templates) do
+          {
+            "" => [
+              { name: "another_issue_template", id: "another_issue_template", project_id: project.id },
+              { name: "custom_issue_template", id: "custom_issue_template", project_id: project.id }
+            ],
+            "Instance" => [
+              { name: "first_issue_issue_template", id: "first_issue_issue_template", project_id: non_existing_record_id },
+              { name: "second_instance_issue_template", id: "second_instance_issue_template", project_id: non_existing_record_id }
+            ]
+          }
+        end
+
+        it 'returns project templates only' do
+          expect(helper.issuable_templates_names(Issue.new)).to eq(%w[another_issue_template custom_issue_template])
+        end
+      end
+
+      context 'without matching project templates' do
+        let(:templates) do
+          {
+            "Project Templates" => [
+              { name: "another_issue_template", id: "another_issue_template", project_id: non_existing_record_id },
+              { name: "custom_issue_template", id: "custom_issue_template", project_id: non_existing_record_id }
+            ],
+            "Instance" => [
+              { name: "first_issue_issue_template", id: "first_issue_issue_template", project_id: non_existing_record_id },
+              { name: "second_instance_issue_template", id: "second_instance_issue_template", project_id: non_existing_record_id }
+            ]
+          }
+        end
+
+        it 'returns empty array' do
+          expect(helper.issuable_templates_names(Issue.new)).to eq([])
+        end
+      end
     end
 
     context 'when there are not templates in the project' do
       let(:templates) { {} }
 
       it 'returns empty array' do
-        allow(helper).to receive(:ref_project).and_return(project)
-        allow(helper).to receive(:issuable_templates).and_return(templates)
-
         expect(helper.issuable_templates_names(Issue.new)).to eq([])
       end
     end

spec/support/shared_examples/helpers/issuable_description_templates_shared_examples.rb

@@ -23,11 +23,11 @@ RSpec.shared_examples 'project issuable templates' do
     end
 
     it 'returns only md files as issue templates' do
-      expect(helper.issuable_templates(project, 'issue')).to eq(templates('issue', project))
+      expect(helper.issuable_templates(project, 'issue')).to eq(expected_templates('issue'))
     end
 
     it 'returns only md files as merge_request templates' do
-      expect(helper.issuable_templates(project, 'merge_request')).to eq(templates('merge_request', project))
+      expect(helper.issuable_templates(project, 'merge_request')).to eq(expected_templates('merge_request'))
     end
   end
 

spec/support/shared_examples/service_desk_issue_templates_examples.rb

+# frozen_string_literal: true
+
+RSpec.shared_examples 'issue description templates from current project only' do
+  it 'loads issue description templates from the project only' do
+    within('#service-desk-template-select') do
+      expect(page).to have_content('project-issue-bar')
+      expect(page).to have_content('project-issue-foo')
+      expect(page).not_to have_content('group-issue-bar')
+      expect(page).not_to have_content('group-issue-foo')
+    end
+  end
+end