Improve wiki page grouping

This uses an intermediate index to transform the function from `O(n^2)`
to `O(n.logn)`, which will be very important for large wikis with lots
of directories, which is definitely something we want to support.

.haml-lint_todo.yml

@@ -343,8 +343,6 @@ linters:
       - 'app/views/projects/triggers/_index.html.haml'
       - 'app/views/projects/triggers/_trigger.html.haml'
       - 'app/views/projects/triggers/edit.html.haml'
-      - 'app/views/projects/wikis/_new.html.haml'
-      - 'app/views/projects/wikis/_pages_wiki_page.html.haml'
       - 'app/views/projects/wikis/edit.html.haml'
       - 'app/views/projects/wikis/history.html.haml'
       - 'app/views/repository_check_mailer/notify.html.haml'

app/assets/javascripts/pages/projects/wiki_directories/index.js

+// currently, this controller inherits all behaviors from wikis
+import '../wikis/index';

app/assets/javascripts/pages/projects/wiki_pages/index.js

+import $ from 'jquery';
+import Vue from 'vue';
+
+import Translate from '~/vue_shared/translate';
+import csrf from '~/lib/utils/csrf';
+import ShortcutsWiki from '~/behaviors/shortcuts/shortcuts_wiki';
+import ZenMode from '~/zen_mode';
+import GLForm from '~/gl_form';
+
+import deleteWikiModal from '../wikis/components/delete_wiki_modal.vue';
+import Wikis from '../wikis/wikis';
+
+document.addEventListener('DOMContentLoaded', () => {
+  new Wikis(); // eslint-disable-line no-new
+  new ShortcutsWiki(); // eslint-disable-line no-new
+  new ZenMode(); // eslint-disable-line no-new
+  new GLForm($('.wiki-form')); // eslint-disable-line no-new
+
+  const deleteWikiModalWrapperEl = document.getElementById('delete-wiki-modal-wrapper');
+
+  if (deleteWikiModalWrapperEl) {
+    Vue.use(Translate);
+
+    const { deleteWikiUrl, pageTitle } = deleteWikiModalWrapperEl.dataset;
+
+    // eslint-disable-next-line no-new
+    new Vue({
+      el: deleteWikiModalWrapperEl,
+      data: {
+        deleteWikiUrl: '',
+      },
+      render(createElement) {
+        return createElement(deleteWikiModal, {
+          props: {
+            pageTitle,
+            deleteWikiUrl,
+            csrfToken: csrf.token,
+          },
+        });
+      },
+    });
+  }
+});

app/assets/javascripts/pages/projects/wikis/index.js

 import $ from 'jquery';
-import Vue from 'vue';
-import Translate from '~/vue_shared/translate';
-import csrf from '~/lib/utils/csrf';
 import ShortcutsWiki from '~/behaviors/shortcuts/shortcuts_wiki';
+import GLForm from '~/gl_form';
+
 import Wikis from './wikis';
-import ZenMode from '../../../zen_mode';
-import GLForm from '../../../gl_form';
-import deleteWikiModal from './components/delete_wiki_modal.vue';
 
 document.addEventListener('DOMContentLoaded', () => {
   new Wikis(); // eslint-disable-line no-new
   new ShortcutsWiki(); // eslint-disable-line no-new
-  new ZenMode(); // eslint-disable-line no-new
   new GLForm($('.wiki-form')); // eslint-disable-line no-new
-
-  const deleteWikiModalWrapperEl = document.getElementById('delete-wiki-modal-wrapper');
-
-  if (deleteWikiModalWrapperEl) {
-    Vue.use(Translate);
-
-    const { deleteWikiUrl, pageTitle } = deleteWikiModalWrapperEl.dataset;
-
-    // eslint-disable-next-line no-new
-    new Vue({
-      el: deleteWikiModalWrapperEl,
-      data: {
-        deleteWikiUrl: '',
-      },
-      render(createElement) {
-        return createElement(deleteWikiModal, {
-          props: {
-            pageTitle,
-            deleteWikiUrl,
-            csrfToken: csrf.token,
-          },
-        });
-      },
-    });
-  }
 });

app/assets/javascripts/pages/projects/wikis/wikis.js

@@ -12,8 +12,8 @@ export default class Wikis {
     }
 
     this.isNewWikiPage = Boolean(document.querySelector('.js-new-wiki-page'));
-    this.editTitleInput = document.querySelector('form.wiki-form #wiki_title');
-    this.commitMessageInput = document.querySelector('form.wiki-form #wiki_message');
+    this.editTitleInput = document.querySelector('form.wiki-form #wiki_page_title');
+    this.commitMessageInput = document.querySelector('form.wiki-form #wiki_page_message');
     this.commitMessageI18n = this.isNewWikiPage
       ? s__('WikiPageCreate|Create %{pageTitle}')
       : s__('WikiPageEdit|Update %{pageTitle}');

app/assets/stylesheets/framework/icons.scss

@@ -99,3 +99,18 @@
   justify-content: center;
   color: $gray-700;
 }
+
+.svg-icon {
+  display: inline-flex;
+  align-self: center;
+
+  svg {
+    height: 1em;
+    width: 1em;
+  }
+
+  &.svg-baseline svg {
+    top: 0.125em;
+    position: relative;
+  }
+}

app/assets/stylesheets/pages/wiki.scss

+.new-wiki-page {
+  .new-wiki-page-slug-tip {
+    display: inline-block;
+    max-width: 100%;
+    margin-top: 5px;
+  }
+}
+
+.wiki-history,
+.wiki-page,
+.edit-wiki-page {
+  margin-right: $gutter-width;
+}
+
+.edit-wiki-page {
+  @media only screen and (min-width: map-get($grid-breakpoints, lg) + (2 * $gutter-width)) and (max-width: map-get($grid-breakpoints, lg) + (3 * $gutter-width)) {
+    margin-right: $gutter-width * 1.5;
+  }
+}
+
+.wiki-form {
+  .edit-wiki-page-slug-tip {
+    display: inline-block;
+    max-width: 100%;
+    margin-top: 5px;
+  }
+}
+
 .title .edit-wiki-header {
   width: 780px;
   margin-left: auto;
@@ -5,6 +33,15 @@
   padding-right: 7px;
 }
 
+.container-fluid.wiki-page,
+.container-fluid.edit-wiki-page {
+  width: initial;
+}
+
+.wiki-history.breadcrumbs {
+  min-height: (2 * $gl-padding) + 22;
+}
+
 .wiki-page-header {
   position: relative;
 
@@ -79,7 +116,7 @@
   }
 
   .sidebar-container {
-    padding: $gl-padding 0;
+    padding-bottom: $gl-padding;
     width: calc(100% + 100px);
     padding-right: 100px;
     height: 100%;
@@ -125,7 +162,7 @@
   }
 
   .wiki-sidebar-header {
-    padding: 0 $gl-padding $gl-padding;
+    padding: $gl-padding;
 
     .gutter-toggle {
       margin-top: 0;

app/controllers/concerns/preview_markdown.rb

@@ -9,11 +9,10 @@ module PreviewMarkdown
 
     markdown_params =
       case controller_name
-      when 'wikis'    then { pipeline: :wiki, project_wiki: @project_wiki, page_slug: params[:id] }
       when 'snippets' then { skip_project_check: true }
       when 'groups'   then { group: group }
       when 'projects' then projects_filter_params
-      else {}
+      else preview_markdown_params
       end
 
     render json: {
@@ -25,6 +24,7 @@ module PreviewMarkdown
       }
     }
   end
+  # rubocop:enable Gitlab/ModuleWithInstanceVariables
 
   def projects_filter_params
     {
@@ -32,5 +32,11 @@ module PreviewMarkdown
       suggestions_filter_enabled: params[:preview_suggestions].present?
     }
   end
-  # rubocop:enable Gitlab/ModuleWithInstanceVariables
+
+  private
+
+  # Override this method to customise the markdown for your controller
+  def preview_markdown_params
+    {}
+  end
 end

app/controllers/concerns/project_wiki_actions.rb

+# frozen_string_literal: true
+
+# Controllers that include this concern must provide:
+#  * project
+#  * current_user
+module ProjectWikiActions
+  extend ActiveSupport::Concern
+
+  included do
+    before_action :authorize_read_wiki!
+    before_action :init_wiki_actions
+
+    attr_accessor :project_wiki, :sidebar_page, :sidebar_wiki_entries
+  end
+
+  def init_wiki_actions
+    load_project_wiki
+    load_wiki_sidebar
+  rescue ProjectWiki::CouldNotCreateWikiError
+    flash[:notice] = _("Could not create Wiki Repository at this time. Please try again later.")
+    redirect_to project_path(project)
+  end
+
+  def load_project_wiki
+    self.project_wiki = load_wiki
+  end
+
+  def load_wiki_sidebar
+    self.sidebar_page = project_wiki.find_sidebar(params[:version_id])
+
+    return if sidebar_page.present?
+
+    # Fallback to default sidebar
+    self.sidebar_wiki_entries = WikiDirectory.group_by_directory(project_wiki.list_pages(limit: 15))
+  end
+
+  def load_wiki
+    # Call #wiki to make sure the Wiki Repo is initialized
+    ProjectWiki.new(project, current_user).tap(&:wiki)
+  end
+end

app/controllers/projects/wiki_directories_controller.rb

+# frozen_string_literal: true
+
+class Projects::WikiDirectoriesController < Projects::ApplicationController
+  include ProjectWikiActions
+
+  def self.local_prefixes
+    [controller_path, 'shared/wiki']
+  end
+
+  def show
+    @wiki_dir = find_dir || WikiDirectory.new(params[:id])
+
+    return render('empty') if @wiki_dir.empty?
+
+    @wiki_entries = @wiki_pages = Kaminari
+      .paginate_array(@wiki_dir.pages)
+      .page(params[:page])
+
+    render 'show'
+  end
+
+  private
+
+  def find_dir
+    dir_params = params.permit(:id, :sort, :direction).dup.tap do |h|
+      Gitlab::Utils.allow_hash_values(h, sort_params_config[:allowed])
+    end
+
+    project_wiki.find_dir(dir_params[:id], dir_params[:sort], dir_params[:direction])
+  end
+end

app/controllers/projects/wiki_pages_controller.rb

+# frozen_string_literal: true
+
+class Projects::WikiPagesController < Projects::ApplicationController
+  include ProjectWikiActions
+  include SendsBlob
+  include PreviewMarkdown
+  include Gitlab::Utils::StrongMemoize
+
+  def self.local_prefixes
+    [controller_path, 'shared/wiki']
+  end
+
+  before_action :authorize_create_wiki!, only: [:edit, :create, :update]
+  before_action :authorize_admin_wiki!, only: :destroy
+
+  before_action :load_page, only: [:show, :edit, :update, :history, :destroy]
+  before_action :valid_encoding?,
+    if: -> { %w[show edit update].include?(action_name) && load_page }
+  before_action only: [:edit, :update], unless: :valid_encoding? do
+    redirect_to(project_wiki_path(@project, @page))
+  end
+
+  def new
+    redirect_to project_wiki_path(@project, SecureRandom.uuid, random_title: true)
+  end
+
+  # `#show` handles a number of scenarios:
+  #
+  # - If `id` matches a WikiPage, then show the wiki page.
+  # - If `id` is a file in the wiki repository, then send the file.
+  # - If we know the user wants to create a new page with the given `id`,
+  #   then display a create form.
+  # - Otherwise show the empty wiki page and invite the user to create a page.
+  def show
+    if @page
+      show_page
+    elsif file_blob
+      show_blob
+    elsif should_create_missing_page?
+      create_missing_page
+    else
+      render 'missing_page'
+    end
+  end
+
+  def edit
+  end
+
+  def update
+    @page = WikiPages::UpdateService
+      .new(@project, current_user, wiki_params)
+      .execute(@page)
+
+    return saved(:updated) if @page.valid?
+
+    render 'edit'
+  rescue WikiPage::PageChangedError, WikiPage::PageRenameError, Gitlab::Git::Wiki::OperationError => e
+    @error = e
+    render 'edit'
+  end
+
+  def create
+    @page = WikiPages::CreateService
+      .new(@project, current_user, wiki_params)
+      .execute
+
+    return saved(:created) if @page.persisted?
+
+    render action: "edit"
+  rescue Gitlab::Git::Wiki::OperationError => e
+    @page = project_wiki.build_page(wiki_params)
+    @error = e
+
+    render 'edit'
+  end
+
+  def history
+    if @page
+      @page_versions = Kaminari.paginate_array(@page.versions(page: params[:page].to_i),
+                                               total_count: @page.count_versions)
+        .page(params[:page])
+    else
+      redirect_to(
+        project_wiki_path(@project, :home),
+        notice: _("Page not found")
+      )
+    end
+  end
+
+  def destroy
+    WikiPages::DestroyService.new(@project, current_user).execute(@page)
+
+    redirect_to project_wiki_path(@project, :home),
+                status: 302,
+                notice: _("Page was successfully deleted")
+  rescue Gitlab::Git::Wiki::OperationError => e
+    @error = e
+    render 'edit'
+  end
+
+  private
+
+  # Callback for PreviewMarkdown
+  def preview_markdown_params
+    { pipeline: :wiki, project_wiki: project_wiki, page_slug: params[:id] }
+  end
+
+  def show_page
+    set_encoding_error unless valid_encoding?
+
+    @page_dir = @project_wiki.find_dir(@page.directory) if @page.directory.present?
+    @show_children = true
+
+    render 'show'
+  end
+
+  def show_blob
+    send_blob(@project_wiki.repository, file_blob)
+  end
+
+  def should_create_missing_page?
+    view_param = @project_wiki.exists? ? 'create' : params[:view]
+    view_param == 'create' && can?(current_user, :create_wiki, @project)
+  end
+
+  def create_missing_page
+    # Assign a title to the WikiPage unless `id` is a randomly generated slug from #new
+    title = params[:id] unless params[:random_title].present?
+
+    @page = project_wiki.build_page(title: title)
+
+    render 'edit'
+  end
+
+  def wiki_params
+    params.require(:wiki_page).permit(:title, :content, :format, :message, :last_commit_sha)
+  end
+
+  def load_page
+    @page ||= @project_wiki.find_page(*page_params)
+  end
+
+  def page_params
+    keys = [:id]
+    keys << :version_id if params[:action] == 'show'
+
+    params.values_at(*keys)
+  end
+
+  def valid_encoding?
+    strong_memoize(:valid_encoding) do
+      @page.content.encoding == Encoding::UTF_8
+    end
+  end
+
+  def set_encoding_error
+    flash.now[:notice] = _("The content of this page is not encoded in UTF-8. Edits can only be made via the Git repository.")
+  end
+
+  def file_blob
+    strong_memoize(:file_blob) do
+      commit = @project_wiki.repository.commit(@project_wiki.default_branch)
+
+      next unless commit
+
+      @project_wiki.repository.blob_at(commit.id, params[:id])
+    end
+  end
+
+  def saved(action)
+    msg = case action
+          when :updated
+            _('Wiki was successfully updated')
+          when :created
+            _('Wiki was successfully created')
+          end
+
+    redirect_to(project_wiki_path(@project, @page), notice: msg)
+  end
+end

app/controllers/projects/wikis_controller.rb

 # frozen_string_literal: true
 
 class Projects::WikisController < Projects::ApplicationController
-  include PreviewMarkdown
-  include SendsBlob
-  include Gitlab::Utils::StrongMemoize
+  include ProjectWikiActions
+  include WikiHelper
 
-  before_action :authorize_read_wiki!
-  before_action :authorize_create_wiki!, only: [:edit, :create]
-  before_action :authorize_admin_wiki!, only: :destroy
-  before_action :load_project_wiki
-  before_action :load_page, only: [:show, :edit, :update, :history, :destroy]
-  before_action :valid_encoding?,
-    if: -> { %w[show edit update].include?(action_name) && load_page }
-  before_action only: [:edit, :update], unless: :valid_encoding? do
-    redirect_to(project_wiki_path(@project, @page))
-  end
-
-  def new
-    redirect_to project_wiki_path(@project, SecureRandom.uuid, random_title: true)
+  def self.local_prefixes
+    [controller_path, 'shared/wiki']
   end
 
   def pages
+    @nesting = show_children_param
+    @show_children = @nesting != ProjectWiki::NESTING_CLOSED
     @wiki_pages = Kaminari.paginate_array(
-      @project_wiki.list_pages(sort: params[:sort], direction: params[:direction])
+      project_wiki.list_pages(**sort_params)
     ).page(params[:page])
 
-    @wiki_entries = WikiPage.group_by_directory(@wiki_pages)
-  end
-
-  # `#show` handles a number of scenarios:
-  #
-  # - If `id` matches a WikiPage, then show the wiki page.
-  # - If `id` is a file in the wiki repository, then send the file.
-  # - If we know the user wants to create a new page with the given `id`,
-  #   then display a create form.
-  # - Otherwise show the empty wiki page and invite the user to create a page.
-  def show
-    if @page
-      set_encoding_error unless valid_encoding?
-
-      render 'show'
-    elsif file_blob
-      send_blob(@project_wiki.repository, file_blob)
-    elsif show_create_form?
-      # Assign a title to the WikiPage unless `id` is a randomly generated slug from #new
-      title = params[:id] unless params[:random_title].present?
-
-      @page = build_page(title: title)
-
-      render 'edit'
+    @wiki_entries = case @nesting
+                    when ProjectWiki::NESTING_FLAT
+                      @wiki_pages
                     else
-      render 'empty'
-    end
-  end
-
-  def edit
-  end
-
-  def update
-    return render('empty') unless can?(current_user, :create_wiki, @project)
-
-    @page = WikiPages::UpdateService.new(@project, current_user, wiki_params).execute(@page)
-
-    if @page.valid?
-      redirect_to(
-        project_wiki_path(@project, @page),
-        notice: _('Wiki was successfully updated.')
-      )
-    else
-      render 'edit'
-    end
-  rescue WikiPage::PageChangedError, WikiPage::PageRenameError, Gitlab::Git::Wiki::OperationError => e
-    @error = e
-    render 'edit'
-  end
-
-  def create
-    @page = WikiPages::CreateService.new(@project, current_user, wiki_params).execute
-
-    if @page.persisted?
-      redirect_to(
-        project_wiki_path(@project, @page),
-        notice: _('Wiki was successfully updated.')
-      )
-    else
-      render action: "edit"
-    end
-  rescue Gitlab::Git::Wiki::OperationError => e
-    @page = build_page(wiki_params)
-    @error = e
-
-    render 'edit'
-  end
-
-  def history
-    if @page
-      @page_versions = Kaminari.paginate_array(@page.versions(page: params[:page].to_i),
-                                               total_count: @page.count_versions)
-        .page(params[:page])
-    else
-      redirect_to(
-        project_wiki_path(@project, :home),
-        notice: _("Page not found")
-      )
-    end
+                      WikiDirectory.group_by_directory(@wiki_pages)
                     end
 
-  def destroy
-    WikiPages::DestroyService.new(@project, current_user).execute(@page)
-
-    redirect_to project_wiki_path(@project, :home),
-                status: 302,
-                notice: _("Page was successfully deleted")
-  rescue Gitlab::Git::Wiki::OperationError => e
-    @error = e
-    render 'edit'
+    render 'show'
   end
 
   def git_access
@@ -122,74 +30,13 @@ class Projects::WikisController < Projects::ApplicationController
 
   private
 
-  def show_create_form?
-    can?(current_user, :create_wiki, @project) &&
-      @page.nil? &&
-      # Always show the create form when the wiki has had at least one page created.
-      # Otherwise, we only show the form when the user has navigated from
-      # the 'empty wiki' page
-      (@project_wiki.exists? || params[:view] == 'create')
-  end
-
-  def load_project_wiki
-    @project_wiki = load_wiki
-
-    # Call #wiki to make sure the Wiki Repo is initialized
-    @project_wiki.wiki
-
-    @sidebar_page = @project_wiki.find_sidebar(params[:version_id])
-
-    unless @sidebar_page # Fallback to default sidebar
-      @sidebar_wiki_entries = WikiPage.group_by_directory(@project_wiki.list_pages(limit: 15))
-    end
-  rescue ProjectWiki::CouldNotCreateWikiError
-    flash[:notice] = _("Could not create Wiki Repository at this time. Please try again later.")
-    redirect_to project_path(@project)
-    false
-  end
-
-  def load_wiki
-    ProjectWiki.new(@project, current_user)
+  def sort_params
+    process_params(sort_params_config)
   end
 
-  def wiki_params
-    params.require(:wiki).permit(:title, :content, :format, :message, :last_commit_sha)
-  end
-
-  def build_page(args = {})
-    WikiPage.new(@project_wiki).tap do |page|
-      page.update_attributes(args) # rubocop:disable Rails/ActiveRecordAliases
-    end
-  end
+  def show_children_param
+    config = nesting_params_config(params[:sort])
 
-  def load_page
-    @page ||= @project_wiki.find_page(*page_params)
-  end
-
-  def page_params
-    keys = [:id]
-    keys << :version_id if params[:action] == 'show'
-
-    params.values_at(*keys)
-  end
-
-  def valid_encoding?
-    strong_memoize(:valid_encoding) do
-      @page.content.encoding == Encoding::UTF_8
-    end
-  end
-
-  def set_encoding_error
-    flash.now[:notice] = _("The content of this page is not encoded in UTF-8. Edits can only be made via the Git repository.")
-  end
-
-  def file_blob
-    strong_memoize(:file_blob) do
-      commit = @project_wiki.repository.commit(@project_wiki.default_branch)
-
-      next unless commit
-
-      @project_wiki.repository.blob_at(commit.id, params[:id])
-    end
+    process_params(config)
   end
 end

app/helpers/icons_helper.rb

@@ -41,6 +41,12 @@ module IconsHelper
     ActionController::Base.helpers.image_path('file_icons.svg', host: sprite_base_url)
   end
 
+  def sprite_icon_with_text(icon_name, content, opts = {})
+    wrapper_class = opts.delete(:wrapper_class)
+    icon = sprite_icon(icon_name, opts)
+    content_tag(:span, [icon, content].join('').html_safe, class: wrapper_class)
+  end
+
   def sprite_icon(icon_name, size: nil, css_class: nil)
     if Gitlab::Sentry.should_raise_for_dev?
       unless known_sprites.include?(icon_name)

app/helpers/wiki_helper.rb

@@ -48,14 +48,23 @@ module WikiHelper
     expose_url(api_v4_projects_wikis_attachments_path(id: @project.id))
   end
 
-  def wiki_sort_controls(project, sort, direction)
-    sort ||= ProjectWiki::TITLE_ORDER
-    link_class = 'btn btn-default has-tooltip reverse-sort-btn qa-reverse-sort rspec-reverse-sort'
-    reversed_direction = direction == 'desc' ? 'asc' : 'desc'
-    icon_class = direction == 'desc' ? 'highest' : 'lowest'
-
-    link_to(project_wikis_pages_path(project, sort: sort, direction: reversed_direction),
-      type: 'button', class: link_class, title: _('Sort direction')) do
+  WIKI_SORT_CSS_CLASSES = 'btn btn-default has-tooltip reverse-sort-btn qa-reverse-sort rspec-reverse-sort'
+
+  def wiki_sort_controls(sort_params = {}, &block)
+    current_sort = sort_params[:sort] || ProjectWiki::TITLE_ORDER
+    current_direction = (sort_params[:direction] || 'asc').inquiry
+
+    reversed_direction = current_direction.desc? ? 'asc' : 'desc'
+    icon_class = current_direction.desc? ? 'highest' : 'lowest'
+
+    sorting = sort_params.merge(sort: current_sort, direction: reversed_direction)
+    opts = {
+      type: 'button',
+      class: WIKI_SORT_CSS_CLASSES,
+      title: _('Sort direction')
+    }
+
+    link_to(yield(sorting), opts) do
       sprite_icon("sort-#{icon_class}", size: 16)
     end
   end
@@ -67,4 +76,86 @@ module WikiHelper
       s_("Wiki|Title")
     end
   end
+
+  # Render the sprite icon given the current show_children state
+  def wiki_show_children_icon(nesting)
+    icon_name, icon_text =
+      case nesting
+      when ProjectWiki::NESTING_TREE
+        ['folder-open', s_("Wiki|Show folder contents")]
+      when ProjectWiki::NESTING_CLOSED
+        ['folder-o', s_("Wiki|Hide folder contents")]
+      else
+        ['list-bulleted', s_("Wiki|Show files separately")]
+      end
+
+    sprite_icon_with_text(icon_name, icon_text, size: 16)
+  end
+
+  def wiki_page_link(wiki_page, nesting, project)
+    link = link_to(wiki_page.title,
+                   project_wiki_path(project, wiki_page),
+                   class: 'wiki-page-title')
+
+    case nesting
+    when ProjectWiki::NESTING_FLAT
+      tags = []
+      if wiki_page.directory.present?
+        wiki_dir = WikiDirectory.new(wiki_page.directory)
+        tags << link_to(wiki_dir.slug, project_wiki_dir_path(project, wiki_dir), class: 'wiki-page-dir-name')
+        tags << content_tag(:span, '/', class: 'wiki-page-name-separator')
+      end
+
+      tags << link
+      tags.join.html_safe
+    else
+      link
+    end
+  end
+
+  def sort_params_config
+    {
+      keys: [:sort, :direction],
+      defaults: {
+        sort: ProjectWiki::TITLE_ORDER, direction: ProjectWiki::DIRECTION_ASC
+      },
+      allowed: {
+        sort: ProjectWiki::SORT_ORDERS, direction: ProjectWiki::SORT_DIRECTIONS
+      }
+    }
+  end
+
+  def nesting_params_config(sort_key)
+    default_val = case sort_key
+                  when ProjectWiki::CREATED_AT_ORDER
+                    ProjectWiki::NESTING_FLAT
+                  else
+                    ProjectWiki::NESTING_CLOSED
+                  end
+    {
+      keys: [:show_children],
+      defaults: { show_children: default_val },
+      allowed: { show_children: ProjectWiki::NESTINGS }
+    }
+  end
+
+  def process_params(config)
+    unprocessed = params.permit(*config[:keys])
+
+    processed = unprocessed
+      .with_defaults(config[:defaults])
+      .tap { |h| Gitlab::Utils.allow_hash_values(h, config[:allowed]) }
+      .to_hash
+      .transform_keys(&:to_sym)
+
+    if processed.keys == config[:keys]
+      processed.size == 1 ? processed.values.first : processed
+    else
+      raise ActionController::BadRequest, "illegal parameters: #{unprocessed}"
+    end
+  end
+
+  def home_page?
+    params[:id] == 'home'
+  end
 end

app/models/project_wiki.rb

@@ -17,6 +17,13 @@ class ProjectWiki
   CREATED_AT_ORDER = 'created_at'
   DIRECTION_DESC = 'desc'
   DIRECTION_ASC = 'asc'
+  SORT_ORDERS = [TITLE_ORDER, CREATED_AT_ORDER].freeze
+  SORT_DIRECTIONS = [DIRECTION_ASC, DIRECTION_DESC].freeze
+
+  NESTING_FLAT = 'flat'
+  NESTING_TREE = 'tree'
+  NESTING_CLOSED = 'hidden'
+  NESTINGS = [NESTING_TREE, NESTING_CLOSED, NESTING_FLAT].freeze
 
   # Returns a string describing what went wrong after
   # an operation fails.
@@ -58,7 +65,11 @@ class ProjectWiki
   end
 
   def wiki_base_path
-    [Gitlab.config.gitlab.relative_url_root, '/', @project.full_path, '/wikis'].join('')
+    ::File.join(project_base_path, 'wikis')
+  end
+
+  def wiki_page_path
+    ::File.join(project_base_path, '-', 'wiki_pages')
   end
 
   # Returns the Gitlab::Git::Wiki object.
@@ -125,6 +136,23 @@ class ProjectWiki
     end
   end
 
+  # Finds directory within the repository based on a slug
+  #
+  # dir_name - The directory prefix.
+  #
+  # Returns an initialized WikiDirectory instance or nil
+  def find_dir(dir_name, sort = nil, direction = DIRECTION_ASC)
+    descending = direction == DIRECTION_DESC
+    # WikiListPagesRequest currently does not support server-side
+    # filtering. Ideally this logic should be moved to the gitaly
+    # side.
+    pages = wiki
+      .list_pages(sort: sort, direction_desc: descending)
+      .map { |page| WikiPage.new(self, page, true) }
+      .select { |wp| wp.directory == dir_name }
+    WikiDirectory.new(dir_name, pages) if pages.present?
+  end
+
   def find_sidebar(version = nil)
     find_page(SIDEBAR, version)
   end
@@ -144,6 +172,12 @@ class ProjectWiki
     false
   end
 
+  def build_page(attrs)
+    WikiPage.new(self).tap do |page|
+      page.update_attributes(attrs) # rubocop:disable Rails/ActiveRecordAliases
+    end
+  end
+
   def update_page(page, content:, title: nil, format: :markdown, message: nil)
     commit = commit_details(:updated, message, page.title)
 
@@ -171,7 +205,7 @@ class ProjectWiki
 
     title_array = title.split("/")
     title = title_array.pop
-    [title, title_array.join("/")]
+    [title, ::File.join(title_array)]
   end
 
   def repository
@@ -198,6 +232,10 @@ class ProjectWiki
 
   private
 
+  def project_base_path
+    ::File.join(Gitlab.config.gitlab.relative_url_root, @project.full_path)
+  end
+
   def create_repo!(raw_repository)
     gitlab_shell.create_wiki_repository(project)
 

app/models/wiki_directory.rb

 # frozen_string_literal: true
 
 class WikiDirectory
+  include StaticModel
   include ActiveModel::Validations
 
   attr_accessor :slug, :pages
 
   validates :slug, presence: true
 
+  # StaticModel overrides and configuration:
+
+  def self.primary_key
+    'slug'
+  end
+
+  def id
+    "#{slug}@#{last_version&.sha}"
+  end
+
+  def self.model_name
+    ActiveModel::Name.new(self, nil, 'wiki_dir')
+  end
+
+  alias_method :to_param, :slug
+  alias_method :title, :slug
+
+  # Sorts and groups pages by directory.
+  #
+  # pages - an array of WikiPage objects.
+  #
+  # Returns an array of WikiPage and WikiDirectory objects.
+  # The entries are sorted in the order of the input array, where
+  # directories appear in the position of their first member.
+  def self.group_by_directory(pages)
+    grouped = []
+    dirs = Hash.new do |h, k|
+      new(k).tap { |dir| grouped << (h[k] = dir) }
+    end
+
+    Array.wrap(pages).each_with_object(grouped) do |page, top_level|
+      group = page.directory.present? ? dirs[page.directory] : top_level
+
+      group << page
+    end
+  end
+
   def initialize(slug, pages = [])
     @slug = slug
     @pages = pages
   end
 
-  # Relative path to the partial to be used when rendering collections
-  # of this object.
-  def to_partial_path
-    'projects/wikis/wiki_directory'
+  def <<(page)
+    @pages << page
+    @last_version = nil
+  end
+
+  def last_version
+    @last_version ||= @pages.map(&:last_version).max_by(&:authored_date)
+  end
+
+  def page_count
+    @pages.size
+  end
+
+  def empty?
+    page_count.zero?
+  end
+
+  def to_partial_path(context = nil)
+    name = [context, 'wiki_directory'].compact.join('_')
+
+    "projects/wiki_directories/#{name}"
   end
 end

app/models/wiki_page.rb

@@ -15,30 +15,7 @@ class WikiPage
   end
 
   def self.model_name
-    ActiveModel::Name.new(self, nil, 'wiki')
-  end
-
-  # Sorts and groups pages by directory.
-  #
-  # pages - an array of WikiPage objects.
-  #
-  # Returns an array of WikiPage and WikiDirectory objects. The entries are
-  # sorted by alphabetical order (directories and pages inside each directory).
-  # Pages at the root level come before everything.
-  def self.group_by_directory(pages)
-    return [] if pages.blank?
-
-    pages.each_with_object([]) do |page, grouped_pages|
-      next grouped_pages << page unless page.directory.present?
-
-      directory = grouped_pages.find do |obj|
-        obj.is_a?(WikiDirectory) && obj.slug == page.directory
-      end
-
-      next directory.pages << page if directory
-
-      grouped_pages << WikiDirectory.new(page.directory, [page])
-    end
+    ActiveModel::Name.new(self, nil, 'wiki_page')
   end
 
   def self.unhyphenize(name)
@@ -66,6 +43,16 @@ class WikiPage
     Gitlab::HookData::WikiPageBuilder.new(self).build
   end
 
+  # Create a new WikiPage
+  #
+  # == Parameters:
+  # wiki::
+  #   A `ProjectWiki` model object
+  # page::
+  #   A `Gitlab::Git::WikiPage` business object, to which this class provides a facade
+  # persisted::
+  #   Is this page fully saved on disk?
+  #
   def initialize(wiki, page = nil, persisted = false)
     @wiki       = wiki
     @page       = page
@@ -250,10 +237,10 @@ class WikiPage
     end
   end
 
-  # Relative path to the partial to be used when rendering collections
-  # of this object.
-  def to_partial_path
-    'projects/wikis/wiki_page'
+  def to_partial_path(context = nil)
+    name = [context, 'wiki_page'].compact.join('_')
+
+    "projects/wiki_pages/#{name}"
   end
 
   def id

app/views/layouts/nav/sidebar/_project.html.haml

@@ -282,14 +282,14 @@
 
       - if project_nav_tab? :wiki
         - wiki_url = project_wiki_path(@project, :home)
-        = nav_link(controller: :wikis) do
+        = nav_link(controller: [:wikis, :wiki_pages, :wiki_directories]) do
           = link_to wiki_url, class: 'shortcuts-wiki', data: { qa_selector: 'wiki_link' } do
             .nav-icon-container
               = sprite_icon('book')
             %span.nav-item-name
               = _('Wiki')
           %ul.sidebar-sub-level-items.is-fly-out-only
-            = nav_link(controller: :wikis, html_options: { class: "fly-out-top-item" } ) do
+            = nav_link(controller: [:wikis, :wiki_pages, :wiki_directories], html_options: { class: "fly-out-top-item" } ) do
               = link_to wiki_url do
                 %strong.fly-out-top-item-name
                   = _('Wiki')

app/views/projects/wiki_directories/_pages_wiki_directory.html.haml

+%li
+  %span.text-secondary-500.svg-icon.svg-baseline
+    - if @show_children
+      = sprite_icon('folder-open', size: 16)
+    - else
+      = sprite_icon('folder-o', size: 16)
+
+  = link_to wiki_dir.slug, project_wiki_dir_path(@project, wiki_dir)
+  - unless @show_children
+    %span.badge.badge-pill.wiki-dir-page-count= wiki_dir.page_count
+    .float-right
+      %small= (s_("Last edited %{date}") % { date: time_ago_with_tooltip(wiki_dir.last_version.authored_date) }).html_safe
+  - if @show_children
+    %ul
+      = render wiki_dir.pages, context: context

app/views/projects/wiki_directories/_sidebar_wiki_directory.html.haml

+%li
+  %span.text-secondary-300.svg-icon.svg-baseline
+    = sprite_icon('folder-open', size: 16)
+
+  = link_to wiki_dir.slug, project_wiki_dir_path(@project, wiki_dir)
+  %ul= render wiki_dir.pages, context: context
+

app/views/projects/wiki_directories/_wiki_directory.html.haml

+= render wiki_directory.to_partial_path(context), wiki_dir: wiki_directory, context: context

app/views/projects/wiki_directories/empty.html.haml

+- layout_path = 'shared/empty_states/wikis_layout'
+- add_to_breadcrumbs _("Wiki"), project_wiki_path(@project, :home)
+- add_to_breadcrumbs s_("Wiki|Pages"), project_wikis_pages_path(@project)
+- breadcrumb_title s_(@wiki_dir.slug)
+- page_title @wiki_dir.slug
+
+- if can?(current_user, :create_wiki, @project)
+  - create_path = project_wiki_path(@project, params[:id], { view: 'create', params: { title: "#{params[:id]}/" } })
+  - create_link = link_to s_('WikiDirEmpty|Create a page in this directory'), create_path, class: 'btn btn-success qa-create-first-page-link', title: s_('WikiDirEmpty|Create a page')
+
+  = render layout: layout_path, locals: { image_path: 'illustrations/wiki_login_empty.svg' } do
+    %h4.text-left
+      = s_('WikiDirEmpty|This directory has no wiki pages')
+    %p.text-left
+      = s_("WikiDirEmpty|A wiki is where you can store all the details about your project. This can include why you've created it, its principles, how to use it, and so on.")
+    = create_link
+
+- elsif can?(current_user, :read_issue, @project)
+  - issues_link = link_to s_('WikiEmptyIssueMessage|issue tracker'), project_issues_path(@project)
+  - new_issue_link = link_to s_('WikiEmpty|Suggest wiki improvement'), new_project_issue_path(@project), class: 'btn btn-success', title: s_('WikiEmptyIssueMessage|Suggest wiki improvement')
+
+  = render layout: layout_path, locals: { image_path: 'illustrations/wiki_logout_empty.svg' } do
+    %h4
+      = s_('WikiDirEmpty|This directory has no wiki pages')
+    %p.text-left
+      = s_('WikiEmptyIssueMessage|You must be a project member in order to add wiki pages. If you have suggestions for how to improve the wiki for this project, consider opening an issue in the %{issues_link}.').html_safe % { issues_link: issues_link }
+    = new_issue_link
+
+- else
+  = render layout: layout_path, locals: { image_path: 'illustrations/wiki_logout_empty.svg' } do
+    %h4
+      = s_('WikiDirEmpty|This directory has no wiki pages')
+    %p
+      = s_('WikiEmpty|You must be a project member in order to add wiki pages.')

app/views/projects/wiki_directories/show.html.haml

+- add_to_breadcrumbs _("Wiki"), project_wiki_path(@project, :home)
+- add_to_breadcrumbs s_("Wiki|Pages"), project_wikis_pages_path(@project)
+- breadcrumb_title s_(@wiki_dir.slug)
+- page_title @wiki_dir.slug
+
+= render 'page_listing', { allow_change_nesting: false, wiki_page_title: page_title, page_path: ->(opts) { project_wiki_dir_path(@project, @wiki_dir, opts) } }

app/views/projects/wikis/_form.html.haml → app/views/projects/wiki_pages/_form.html.haml

 - form_classes = 'wiki-form common-note-form prepend-top-default js-quick-submit'
 - form_classes += ' js-new-wiki-page' unless @page.persisted?
 
-= form_for [@project.namespace.becomes(Namespace), @project, @page], method: @page.persisted? ? :put : :post,
+= form_for [@project.namespace.becomes(Namespace), @project, @page],
+    method: @page.persisted? ? 'put' : 'post',
+    url: { controller: 'wiki_pages', action: @page.persisted? ? :update : :create },
     html: { class: form_classes },
     data: { uploads_path: uploads_path } do |f|
   = form_errors(@page)
@@ -12,7 +14,7 @@
   .form-group.row
     .col-sm-12= f.label :title, class: 'control-label-full-width'
     .col-sm-12
-      = f.text_field :title, class: 'form-control qa-wiki-title-textbox', value: @page.title, required: true, autofocus: !@page.persisted?, placeholder: _('Wiki|Page title')
+      = f.text_field :title, class: 'form-control qa-wiki-title-textbox', value: @page.title, required: true, autofocus: !@page.persisted?, placeholder: s_('Wiki|Page title')
       %span.d-inline-block.mw-100.prepend-top-5
         = icon('lightbulb-o')
         - if @page.persisted?

app/views/projects/wiki_pages/_page_title.html.haml

+= link_to @page.human_title, project_wiki_path(@project, @page)
+%span.light
+  = _('·').html_safe
+  = subtitle

app/views/projects/wikis/_pages_wiki_page.html.haml → app/views/projects/wiki_pages/_pages_wiki_page.html.haml

 %li
-  = link_to wiki_page.title, project_wiki_path(@project, wiki_page)
-  %small (#{wiki_page.format})
+  %span.text-secondary-500.svg-icon.svg-baseline= sprite_icon('book', size: 16)
+  = wiki_page_link(wiki_page, @nesting, @project)
   .float-right
+    %span.badge.badge-pill.wiki-page-format= _(wiki_page.format)
     - if wiki_page.last_version
+      = '/'
       %small= (s_("Last edited %{date}") % { date: time_ago_with_tooltip(wiki_page.last_version.authored_date) }).html_safe

app/views/projects/wiki_pages/_sidebar_wiki_page.html.haml

+- is_active = params[:id] == wiki_page.slug
+- icon_active_class = is_active ? 'text-secondary-800' : 'text-secondary-300'
+
+%li{ class: active_when(is_active) }
+  %span.svg-icon.svg-baseline{ class: icon_active_class }
+    = sprite_icon('book', size: 16)
+  - if is_active
+    = wiki_page.human_title
+  - else
+    = link_to project_wiki_path(@project, wiki_page) do
+      = wiki_page.human_title

app/views/projects/wiki_pages/_wiki_page.html.haml

+= render wiki_page.to_partial_path(context), wiki_page: wiki_page

app/views/projects/wikis/edit.html.haml → app/views/projects/wiki_pages/edit.html.haml

-- @content_class = "limit-container-width" unless fluid_layout
-- add_to_breadcrumbs _("Wiki"), project_wiki_path(@project, @page)
+- @content_class = 'edit-wiki-page' + (fluid_layout ? '' : ' limit-container-width')
+- add_to_breadcrumbs _("Wiki"), project_wiki_path(@project, :home)
+- add_to_breadcrumbs s_("Wiki|Pages"), project_wikis_pages_path(@project)
+- if @page.persisted? && @page_dir.present?
+  - add_to_breadcrumbs _(@page_dir.slug), project_wiki_dir_path(@project, @page_dir)
+- if @page.persisted?
+  - add_to_breadcrumbs @page.human_title, project_wiki_path(@project, @page)
 - breadcrumb_title @page.persisted? ? _("Edit") : _("New")
 - page_title @page.persisted? ? _("Edit") : _("New"), @page.human_title, _("Wiki")
 
@@ -12,10 +17,7 @@
   .nav-text
     %h2.wiki-page-title
       - if @page.persisted?
-        = link_to @page.human_title, project_wiki_path(@project, @page)
-        %span.light
-          ·
-          = s_("Wiki|Edit Page")
+        = render partial: 'page_title', locals: { subtitle: s_("Wiki|Edit Page") }
       - else
         = s_("Wiki|Create New Page")
 

app/views/projects/wikis/history.html.haml → app/views/projects/wiki_pages/history.html.haml

+- @content_class = 'wiki-history'
 - page_title _("History"), @page.human_title, _("Wiki")
 
 .wiki-page-header.top-area.has-sidebar-toggle.flex-column.flex-lg-row
@@ -6,10 +7,7 @@
 
   .nav-text
     %h2.wiki-page-title
-      = link_to @page.human_title, project_wiki_path(@project, @page)
-      %span.light
-        ·
-        = _("History")
+      = render partial: 'page_title', locals: { subtitle: _("History") }
 
 .table-holder
   %table.table
@@ -39,4 +37,4 @@
               = version.format
 = paginate @page_versions, theme: 'gitlab'
 
-= render 'sidebar'
+= render 'shared/wiki/sidebar'

app/views/projects/wiki_pages/show.html.haml

+- @content_class = 'wiki-page' + (fluid_layout ? '' : ' limit-container-width')
+- breadcrumb_title @page.human_title
+- page_title @page.human_title, _("Wiki")
+- add_to_breadcrumbs _("Wiki"), project_wiki_path(@project, :home)
+- add_to_breadcrumbs s_("Wiki|Pages"), project_wikis_pages_path(@project)
+- if @page_dir.present?
+  - add_to_breadcrumbs _(@page_dir.slug), project_wiki_dir_path(@project, @page_dir)
+
+.wiki-page-header.top-area.has-sidebar-toggle.flex-column.flex-lg-row
+  %button.btn.btn-default.sidebar-toggle.js-sidebar-wiki-toggle{ role: "button", type: "button" }
+    = icon('angle-double-left')
+
+  .nav-text.flex-fill
+    %h2.wiki-page-title= @page.human_title
+    %span.wiki-last-edit-by
+      - if @page.last_version
+        = (_("Last edited by %{name}") % { name: "<strong>#{@page.last_version.author_name}</strong>" }).html_safe
+        #{time_ago_with_tooltip(@page.last_version.authored_date)}
+
+  .nav-controls.pb-md-3.pb-lg-0
+    = render 'main_links'
+
+- if @page.historical?
+  .warning_message
+    = s_("WikiHistoricalPage|This is an old version of this page.")
+    - most_recent_link = link_to s_("WikiHistoricalPage|most recent version"), project_wiki_path(@project, @page)
+    - history_link = link_to s_("WikiHistoricalPage|history"), project_wiki_history_path(@project, @page)
+    = (s_("WikiHistoricalPage|You can view the %{most_recent_link} or browse the %{history_link}.") % { most_recent_link: most_recent_link, history_link: history_link }).html_safe
+
+.prepend-top-default.append-bottom-default
+  .md.md-file.qa-wiki-page-content
+    = render_wiki_content(@page)
+
+= render 'sidebar'

app/views/projects/wikis/_sidebar_wiki_page.html.haml

-%li{ class: active_when(params[:id] == wiki_page.slug) }
-  = link_to project_wiki_path(@project, wiki_page) do
-    = wiki_page.human_title

app/views/projects/wikis/_wiki_directory.html.haml

-%li
-  = wiki_directory.slug
-  %ul
-    = render wiki_directory.pages, context: context

app/views/projects/wikis/_wiki_page.html.haml

-= render "#{context}_wiki_page", wiki_page: wiki_page

app/views/projects/wikis/pages.html.haml

-- add_to_breadcrumbs "Wiki", project_wiki_path(@project, :home)
-- breadcrumb_title s_("Wiki|Pages")
-- page_title s_("Wiki|Pages"), _("Wiki")
-- sort_title = wiki_sort_title(params[:sort])
-
-.wiki-page-header.top-area.flex-column.flex-lg-row
-
-  .nav-text.flex-fill
-    %h2.wiki-page-title
-      = s_("Wiki|Wiki Pages")
-
-  .nav-controls.pb-md-3.pb-lg-0
-    = link_to project_wikis_git_access_path(@project), class: 'btn' do
-      = icon('cloud-download')
-      = _("Clone repository")
-
-    .dropdown.inline.wiki-sort-dropdown
-      .btn-group{ role: 'group' }
-        .btn-group{ role: 'group' }
-          %button.dropdown-toggle{ type: 'button', data: { toggle: 'dropdown', display: 'static' }, class: 'btn btn-default' }
-            = sort_title
-            = icon('chevron-down')
-          %ul.dropdown-menu.dropdown-menu-right.dropdown-menu-selectable.dropdown-menu-sort
-            %li
-              = sortable_item(s_("Wiki|Title"), project_wikis_pages_path(@project, sort: ProjectWiki::TITLE_ORDER), sort_title)
-              = sortable_item(s_("Wiki|Created date"), project_wikis_pages_path(@project, sort: ProjectWiki::CREATED_AT_ORDER), sort_title)
-        = wiki_sort_controls(@project, params[:sort], params[:direction])
-
-%ul.wiki-pages-list.content-list
-  = render @wiki_entries, context: 'pages'
-
-= paginate @wiki_pages, theme: 'gitlab'

app/views/projects/wikis/show.html.haml

-- @content_class = "limit-container-width" unless fluid_layout
-- breadcrumb_title @page.human_title
-- wiki_breadcrumb_dropdown_links(@page.slug)
-- page_title @page.human_title, _("Wiki")
-- add_to_breadcrumbs _("Wiki"), project_wiki_path(@project, :home)
+- add_to_breadcrumbs "Wiki", project_wiki_path(@project, :home)
+- breadcrumb_title s_("Wiki|Pages")
+- page_title s_("Wiki|Contents"), _("Wiki")
 
-.wiki-page-header.top-area.has-sidebar-toggle.flex-column.flex-lg-row
-  %button.btn.btn-default.sidebar-toggle.js-sidebar-wiki-toggle{ role: "button", type: "button" }
-    = icon('angle-double-left')
-
-  .nav-text.flex-fill
-    %h2.wiki-page-title= @page.human_title
-    %span.wiki-last-edit-by
-      - if @page.last_version
-        = (_("Last edited by %{name}") % { name: "<strong>#{@page.last_version.author_name}</strong>" }).html_safe
-        #{time_ago_with_tooltip(@page.last_version.authored_date)}
-
-  .nav-controls.pb-md-3.pb-lg-0
-    = render 'main_links'
-
-- if @page.historical?
-  .warning_message
-    = s_("WikiHistoricalPage|This is an old version of this page.")
-    - most_recent_link = link_to s_("WikiHistoricalPage|most recent version"), project_wiki_path(@project, @page)
-    - history_link = link_to s_("WikiHistoricalPage|history"), project_wiki_history_path(@project, @page)
-    = (s_("WikiHistoricalPage|You can view the %{most_recent_link} or browse the %{history_link}.") % { most_recent_link: most_recent_link, history_link: history_link }).html_safe
-
-.prepend-top-default.append-bottom-default
-  .md.md-file{ data: { qa_selector: 'wiki_page_content' } }
-    = render_wiki_content(@page)
-
-= render 'sidebar'
+= render 'page_listing', { allow_change_nesting: ::Feature.enabled?(:wikis_allow_change_nesting), wiki_page_title: page_title, page_path: ->(opts) { project_wikis_pages_path(@project, opts) } }

app/views/shared/empty_states/_wikis.html.haml

 - layout_path = 'shared/empty_states/wikis_layout'
+- wiki_is_empty = @project_wiki.empty?
+- empty_msg  = wiki_is_empty ? s_('WikiEmpty|This project has no wiki pages') : s_('WikiEmpty|This page does not exist')
+- create_msg = wiki_is_empty ? s_('WikiEmpty|Create your first page')         : s_('WikiEmpty|Create this page')
 
 - if can?(current_user, :create_wiki, @project)
   - create_path = project_wiki_path(@project, params[:id], { view: 'create' })
-  - create_link = link_to s_('WikiEmpty|Create your first page'), create_path, class: 'btn btn-success qa-create-first-page-link', title: s_('WikiEmpty|Create your first page')
+  - create_link = link_to create_msg, create_path, class: 'btn btn-success qa-create-first-page-link', title: create_msg
 
   = render layout: layout_path, locals: { image_path: 'illustrations/wiki_login_empty.svg' } do
     %h4.text-left
@@ -17,7 +20,7 @@
 
   = render layout: layout_path, locals: { image_path: 'illustrations/wiki_logout_empty.svg' } do
     %h4
-      = s_('WikiEmpty|This project has no wiki pages')
+      = empty_msg
     %p.text-left
       = s_('WikiEmptyIssueMessage|You must be a project member in order to add wiki pages. If you have suggestions for how to improve the wiki for this project, consider opening an issue in the %{issues_link}.').html_safe % { issues_link: issues_link }
     = new_issue_link
@@ -25,6 +28,6 @@
 - else
   = render layout: layout_path, locals: { image_path: 'illustrations/wiki_logout_empty.svg' } do
     %h4
-      = s_('WikiEmpty|This project has no wiki pages')
+      = empty_msg
     %p
       = s_('WikiEmpty|You must be a project member in order to add wiki pages.')

app/views/projects/wikis/_main_links.html.haml → app/views/shared/wiki/_main_links.html.haml

 - if (@page && @page.persisted?)
   - if can?(current_user, :create_wiki, @project)
-    = link_to project_wikis_new_path(@project), class: "add-new-wiki btn btn-success", role: "button" do
+    = link_to project_wiki_pages_new_path(@project), class: "add-new-wiki btn btn-success", role: "button" do
       = s_("Wiki|New page")
   = link_to project_wiki_history_path(@project, @page), class: "btn", role: "button" do
     = s_("Wiki|Page history")

app/views/shared/wiki/_page_listing.html.haml

+- @no_container = true
+- current_sorting = params.permit(:sort, :direction)
+- sort_title = wiki_sort_title(params[:sort])
+
+%div{ class: container_class }
+  .wiki-page-header.top-area.flex-column.flex-lg-row
+
+    .nav-text.flex-fill
+      %h2.wiki-page-title
+        = wiki_page_title
+
+    .nav-controls.pb-md-3.pb-lg-0
+      - if can?(current_user, :create_wiki, @project)
+        = link_to project_wiki_pages_new_path(@project), class: "add-new-wiki btn btn-success" do
+          = s_("Wiki|New page")
+
+      = link_to project_wikis_git_access_path(@project), class: 'btn qa-clone-repository-link' do
+        = sprite_icon('download', size: 16)
+        = _("Clone repository")
+
+      - if @nesting.present? && allow_change_nesting
+        .dropdown.inline.wiki-nesting-dropdown
+          .btn-group{ role: 'group' }
+            %button.dropdown-toggle{ type: 'button', data: { toggle: 'dropdown', display: 'static' }, class: 'btn btn-default' }
+              = wiki_show_children_icon(@nesting)
+              = sprite_icon('chevron-down', size: 16)
+            %ul.dropdown-menu.dropdown-menu-right.dropdown-menu-selectable.dropdown-menu-sort
+              - ProjectWiki::NESTINGS.each do |choice|
+                %li= link_to wiki_show_children_icon(choice), page_path.call(current_sorting.merge(show_children: choice)), class: @nesting == choice ? 'is-active' : ''
+
+      .dropdown.inline.wiki-sort-dropdown
+        .btn-group{ role: 'group' }
+          %button.dropdown-toggle{ type: 'button', data: { toggle: 'dropdown', display: 'static' }, class: 'btn btn-default' }
+            = sort_title
+            = sprite_icon('chevron-down', size: 16)
+          %ul.dropdown-menu.dropdown-menu-right.dropdown-menu-selectable.dropdown-menu-sort
+            %li
+              = sortable_item(s_("Wiki|Title"), page_path.call(sort: ProjectWiki::TITLE_ORDER), sort_title)
+              = sortable_item(s_("Wiki|Created date"), page_path.call(sort: ProjectWiki::CREATED_AT_ORDER), sort_title)
+          = wiki_sort_controls(current_sorting.merge(show_children: @nesting), &page_path)
+
+  %ul.wiki-pages-list.content-list
+    = render @wiki_entries, context: 'pages'
+
+  = paginate @wiki_pages, theme: 'gitlab'

changelogs/unreleased/sort-wiki-pages-by-date.yml

+---
+title: Sort wiki pages by date
+merge_request: 30245
+type: added

config/routes/project.rb

@@ -615,7 +615,7 @@ constraints(::Constraints::ProjectUrlConstrainer.new) do
       end
 
       # Since both wiki and repository routing contains wildcard characters
-      # its preferable to keep it below all other project routes
+      # its preferable to keep them below all other project routes
       draw :wiki
       draw :repository
 

config/routes/wiki.rb

 scope(controller: :wikis) do
+  scope(path: 'wikis/pages', as: :wiki_pages, format: false) do
+    get :new, to: 'wiki_pages#new'
+    post '/', to: 'wiki_pages#create'
+  end
+
   scope(path: 'wikis', as: :wikis) do
     get :git_access
     get :pages
-    get :new
-    get '/', to: redirect('%{namespace_id}/%{project_id}/wikis/home')
-    post '/', to: 'wikis#create'
+    get '/', to: redirect('%{namespace_id}/%{project_id}/-/wiki_pages/home')
+    get '/*id', to: redirect('%{namespace_id}/%{project_id}/-/wiki_pages/%{id}')
+  end
+
+  scope(path: '-/wiki_pages', as: :wiki_page, format: false) do
+    post '/', to: 'wiki_pages#create'
   end
 
-  scope(path: 'wikis/*id', as: :wiki, format: false) do
+  scope(path: '-/wiki_pages/*id', as: :wiki, format: false, controller: :wiki_pages) do
     get :edit
     get :history
     post :preview_markdown
@@ -15,4 +23,8 @@ scope(controller: :wikis) do
     put '/', action: :update
     delete '/', action: :destroy
   end
+
+  scope(path: '-/wiki_dirs/*id', as: :wiki_dir, format: false, controller: :wiki_directories) do
+    get '/', action: :show
+  end
 end

lib/banzai/filter/wiki_link_filter/rewriter.rb

@@ -6,7 +6,7 @@ module Banzai
       class Rewriter
         def initialize(link_string, wiki:, slug:)
           @uri = Addressable::URI.parse(link_string)
-          @wiki_base_path = wiki && wiki.wiki_base_path
+          @wiki_base_path = wiki && wiki.wiki_page_path
           @slug = slug
         end
 

lib/gitlab/utils.rb

@@ -130,5 +130,15 @@ module Gitlab
       IPAddr.new(str)
     rescue IPAddr::InvalidAddressError
     end
+
+    # Filter a Hash against a mapping of keys to sets of allowed values.
+    #
+    # Keys that do not pass the filter will be removed from the Hash.
+    # This mutates the input hash.
+    def allow_hash_values(hash, allowed)
+      allowed.each do |key, allowed_values|
+        hash.delete(key) if hash.key?(key) && !allowed_values.include?(hash[key])
+      end
+    end
   end
 end

locale/gitlab.pot

@@ -411,6 +411,9 @@ msgstr ""
 msgid "%{verb} %{time_spent_value} spent time."
 msgstr ""
 
+msgid "·"
+msgstr ""
+
 msgid "'%{level}' is not a valid visibility level"
 msgstr ""
 
@@ -18704,7 +18707,10 @@ msgstr ""
 msgid "Wiki pages"
 msgstr ""
 
-msgid "Wiki was successfully updated."
+msgid "Wiki was successfully created"
+msgstr ""
+
+msgid "Wiki was successfully updated"
 msgstr ""
 
 msgid "WikiClone|Clone your wiki"
@@ -18722,6 +18728,18 @@ msgstr ""
 msgid "WikiClone|Start Gollum and edit locally"
 msgstr ""
 
+msgid "WikiDirEmpty|A wiki is where you can store all the details about your project. This can include why you've created it, its principles, how to use it, and so on."
+msgstr ""
+
+msgid "WikiDirEmpty|Create a page"
+msgstr ""
+
+msgid "WikiDirEmpty|Create a page in this directory"
+msgstr ""
+
+msgid "WikiDirEmpty|This directory has no wiki pages"
+msgstr ""
+
 msgid "WikiEditPageTip|Tip: You can move this page by adding the path to the beginning of the title."
 msgstr ""
 
@@ -18740,6 +18758,9 @@ msgstr ""
 msgid "WikiEmpty|A wiki is where you can store all the details about your project. This can include why you've created it, its principles, how to use it, and so on."
 msgstr ""
 
+msgid "WikiEmpty|Create this page"
+msgstr ""
+
 msgid "WikiEmpty|Create your first page"
 msgstr ""
 
@@ -18749,6 +18770,9 @@ msgstr ""
 msgid "WikiEmpty|The wiki lets you write documentation for your project"
 msgstr ""
 
+msgid "WikiEmpty|This page does not exist"
+msgstr ""
+
 msgid "WikiEmpty|This project has no wiki pages"
 msgstr ""
 
@@ -18803,6 +18827,9 @@ msgstr ""
 msgid "WikiPage|Write your content or drag files here…"
 msgstr ""
 
+msgid "Wiki|Contents"
+msgstr ""
+
 msgid "Wiki|Create New Page"
 msgstr ""
 
@@ -18815,6 +18842,9 @@ msgstr ""
 msgid "Wiki|Edit Page"
 msgstr ""
 
+msgid "Wiki|Hide folder contents"
+msgstr ""
+
 msgid "Wiki|More Pages"
 msgstr ""
 
@@ -18833,10 +18863,13 @@ msgstr ""
 msgid "Wiki|Pages"
 msgstr ""
 
-msgid "Wiki|Title"
+msgid "Wiki|Show files separately"
 msgstr ""
 
-msgid "Wiki|Wiki Pages"
+msgid "Wiki|Show folder contents"
+msgstr ""
+
+msgid "Wiki|Title"
 msgstr ""
 
 msgid "Will deploy to"

qa/qa/page/project/wiki/edit.rb

@@ -5,7 +5,7 @@ module QA
     module Project
       module Wiki
         class Edit < Page::Base
-          view 'app/views/projects/wikis/_main_links.html.haml' do
+          view 'app/views/shared/wiki/_main_links.html.haml' do
             element :new_page_link, 'New page' # rubocop:disable QA/ElementWithPattern
             element :page_history_link, 'Page history' # rubocop:disable QA/ElementWithPattern
             element :edit_page_link, 'Edit' # rubocop:disable QA/ElementWithPattern

qa/qa/page/project/wiki/new.rb

@@ -7,7 +7,7 @@ module QA
         class New < Page::Base
           include Component::LazyLoader
 
-          view 'app/views/projects/wikis/_form.html.haml' do
+          view 'app/views/projects/wiki_pages/_form.html.haml' do
             element :wiki_title_textbox
             element :wiki_content_textarea
             element :wiki_message_textbox

qa/qa/page/project/wiki/show.rb

@@ -7,11 +7,11 @@ module QA
         class Show < Page::Base
           include Page::Component::LegacyClonePanel
 
-          view 'app/views/projects/wikis/pages.html.haml' do
+          view 'app/views/shared/wiki/_page_listing.html.haml' do
             element :clone_repository_link, 'Clone repository' # rubocop:disable QA/ElementWithPattern
           end
 
-          view 'app/views/projects/wikis/show.html.haml' do
+          view 'app/views/projects/wiki_pages/show.html.haml' do
             element :wiki_page_content
           end
 

qa/qa/specs/features/browser_ui/3_create/wiki/create_edit_clone_push_wiki_spec.rb

@@ -13,7 +13,7 @@ module QA
           resource.message = 'Update home'
         end
 
-        validate_content('My First Wiki Content')
+        validate_created('My First Wiki Content')
 
         Page::Project::Wiki::Edit.perform(&:click_edit)
         Page::Project::Wiki::New.perform do |page| # rubocop:disable QA/AmbiguousPageObjectName
@@ -21,7 +21,7 @@ module QA
           page.save_changes
         end
 
-        validate_content('My Second Wiki Content')
+        validate_edited('My Second Wiki Content')
 
         Resource::Repository::WikiPush.fabricate! do |push|
           push.wiki = wiki
@@ -34,7 +34,12 @@ module QA
         expect(page).to have_content('My Third Wiki Content')
       end
 
-      def validate_content(content)
+      def validate_created(content)
+        expect(page).to have_content('Wiki was successfully created')
+        expect(page).to have_content(/#{content}/)
+      end
+
+      def validate_edited(content)
         expect(page).to have_content('Wiki was successfully updated')
         expect(page).to have_content(/#{content}/)
       end

spec/controllers/projects/wiki_directories_controller_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe Projects::WikiDirectoriesController do
+  set(:project) { create(:project, :public, :repository) }
+
+  let(:user) { project.owner }
+  let(:project_wiki) { ProjectWiki.new(project, user) }
+  let(:wiki) { project_wiki.wiki }
+  let(:dir_slug) { 'the-directory' }
+  let(:dir_contents) { [create(:wiki_page)] }
+  let(:the_dir) { WikiDirectory.new(dir_slug, dir_contents) }
+
+  before do
+    allow(controller).to receive(:find_dir).and_return(the_dir)
+
+    sign_in(user)
+  end
+
+  describe 'GET #show' do
+    let(:show_params) do
+      {
+        namespace_id: project.namespace,
+        project_id: project,
+        id: dir_slug
+      }
+    end
+
+    before do
+      get :show, params: show_params
+    end
+
+    context 'the directory is empty' do
+      let(:the_dir) { nil }
+
+      it { is_expected.to render_template('empty') }
+    end
+
+    context 'the directory does exist' do
+      it { is_expected.to render_template('show') }
+
+      it 'sets the wiki_dir attribute' do
+        expect(assigns(:wiki_dir)).to eq(the_dir)
+      end
+
+      it 'assigns the wiki pages' do
+        expect(assigns(:wiki_pages)).to eq(dir_contents)
+      end
+    end
+  end
+end

spec/controllers/projects/wikis_controller_spec.rb

@@ -4,10 +4,10 @@ require 'spec_helper'
 
 describe Projects::WikisController do
   let_it_be(:project) { create(:project, :public, :repository) }
-  let(:user) { project.owner }
-  let(:project_wiki) { ProjectWiki.new(project, user) }
-  let(:wiki) { project_wiki.wiki }
-  let(:wiki_title) { 'page title test' }
+  let_it_be(:user) { project.owner }
+  let_it_be(:project_wiki) { ProjectWiki.new(project, user) }
+  let_it_be(:wiki) { project_wiki.wiki }
+  let_it_be(:wiki_title) { 'page title test' }
 
   before do
     create_page(wiki_title, 'hello world')
@@ -19,231 +19,86 @@ describe Projects::WikisController do
     destroy_page(wiki_title)
   end
 
-  describe 'GET #new' do
-    subject { get :new, params: { namespace_id: project.namespace, project_id: project } }
-
-    it 'redirects to #show and appends a `random_title` param' do
-      subject
-
-      expect(response).to have_http_status(302)
-      expect(Rails.application.routes.recognize_path(response.redirect_url)).to include(
-        controller: 'projects/wikis',
-        action: 'show'
-      )
-      expect(response.redirect_url).to match(/\?random_title=true\Z/)
-    end
+  describe 'GET #pages' do
+    subject do
+      get :pages, params: { namespace_id: project.namespace, project_id: project, id: wiki_title }.merge(extra_params)
     end
 
-  describe 'GET #pages' do
-    subject { get :pages, params: { namespace_id: project.namespace, project_id: project, id: wiki_title } }
+    let(:extra_params) { {} }
 
     it 'does not load the pages content' do
       expect(controller).to receive(:load_wiki).and_return(project_wiki)
-
       expect(project_wiki).to receive(:list_pages).twice.and_call_original
 
       subject
     end
-  end
 
-  describe 'GET #history' do
-    before do
-      allow(controller)
-        .to receive(:can?)
-        .with(any_args)
-        .and_call_original
-
-      # The :create_wiki permission is irrelevant to reading history.
-      expect(controller)
-        .not_to receive(:can?)
-        .with(anything, :create_wiki, any_args)
-
-      allow(controller)
-        .to receive(:can?)
-        .with(anything, :read_wiki, any_args)
-        .and_return(allow_read_wiki)
+    describe 'illegal params' do
+      shared_examples :a_bad_request do
+        it do
+          expect { subject }.to raise_error(ActionController::BadRequest)
         end
-
-    shared_examples 'fetching history' do |expected_status|
-      before do
-        get :history, params: { namespace_id: project.namespace, project_id: project, id: wiki_title }
       end
 
-      it "returns status #{expected_status}" do
-        expect(response).to have_http_status(expected_status)
-      end
-    end
-
-    it_behaves_like 'fetching history', :ok do
-      let(:allow_read_wiki)   { true }
-
-      it 'assigns @page_versions' do
-        expect(assigns(:page_versions)).to be_present
-      end
-    end
+      describe ':sort' do
+        let(:extra_params) { { sort: 'wibble' } }
 
-    it_behaves_like 'fetching history', :not_found do
-      let(:allow_read_wiki)   { false }
-    end
+        it_behaves_like :a_bad_request
       end
 
-  describe 'GET #show' do
-    render_views
-
-    let(:random_title) { nil }
-
-    subject { get :show, params: { namespace_id: project.namespace, project_id: project, id: id, random_title: random_title } }
-
-    context 'when page exists' do
-      let(:id) { wiki_title }
+      describe ':direction' do
+        let(:extra_params) { { direction: 'wibble' } }
 
-      it 'limits the retrieved pages for the sidebar' do
-        expect(controller).to receive(:load_wiki).and_return(project_wiki)
-        expect(project_wiki).to receive(:list_pages).with(limit: 15).and_call_original
-
-        subject
-
-        expect(response).to have_http_status(:ok)
-        expect(assigns(:page).title).to eq(wiki_title)
+        it_behaves_like :a_bad_request
       end
 
-      context 'when page content encoding is invalid' do
-        it 'sets flash error' do
-          allow(controller).to receive(:valid_encoding?).and_return(false)
+      describe ':show_children' do
+        let(:extra_params) { { show_children: 'wibble' } }
 
-          subject
-
-          expect(response).to have_http_status(:ok)
-          expect(flash[:notice]).to eq('The content of this page is not encoded in UTF-8. Edits can only be made via the Git repository.')
-        end
+        it_behaves_like :a_bad_request
       end
     end
 
-    context 'when the page does not exist' do
-      let(:id) { 'does not exist' }
+    shared_examples 'sorting-and-nesting' do |sort_key, default_nesting|
+      context "the user is sorting by #{sort_key}" do
+        let(:extra_params) { sort_params.merge(nesting_params) }
+        let(:sort_params) { { sort: sort_key } }
+        let(:nesting_params) { {} }
 
         before do
           subject
         end
 
-      it 'builds a new wiki page with the id as the title' do
-        expect(assigns(:page).title).to eq(id)
+        it "sets nesting to #{default_nesting} by default" do
+          expect(assigns :nesting).to eq default_nesting
         end
 
-      context 'when a random_title param is present' do
-        let(:random_title) { true }
-
-        it 'builds a new wiki page with no title' do
-          expect(assigns(:page).title).to be_empty
-        end
-      end
+        it 'hides children if the default requires it' do
+          expect(assigns :show_children).to be(default_nesting != ProjectWiki::NESTING_CLOSED)
         end
 
-    context 'when page is a file' do
-      include WikiHelpers
+        ProjectWiki::NESTINGS.each do |nesting|
+          context "the user explicitly passes show_children = #{nesting}" do
+            let(:nesting_params) { { show_children: nesting } }
 
-      let(:id) { upload_file_to_wiki(project, user, file_name) }
-
-      before do
-        subject
-      end
-
-      context 'when file is an image' do
-        let(:file_name) { 'dk.png' }
-
-        it 'delivers the image' do
-          expect(response.headers['Content-Disposition']).to match(/^inline/)
-          expect(response.headers[Gitlab::Workhorse::DETECT_HEADER]).to eq "true"
-        end
-
-        context 'when file is a svg' do
-          let(:file_name) { 'unsanitized.svg' }
-
-          it 'delivers the image' do
-            expect(response.headers['Content-Disposition']).to match(/^inline/)
-            expect(response.headers[Gitlab::Workhorse::DETECT_HEADER]).to eq "true"
+            it 'sets nesting to the provided value' do
+              expect(assigns :nesting).to eq nesting
             end
           end
         end
 
-      context 'when file is a pdf' do
-        let(:file_name) { 'git-cheat-sheet.pdf' }
+        context 'the user wants children hidden' do
+          let(:nesting_params) { { show_children: 'hidden' } }
 
-        it 'sets the content type to sets the content response headers' do
-          expect(response.headers['Content-Disposition']).to match(/^inline/)
-          expect(response.headers[Gitlab::Workhorse::DETECT_HEADER]).to eq "true"
+          it 'hides children' do
+            expect(assigns :show_children).to be false
           end
         end
       end
     end
 
-  describe 'POST #preview_markdown' do
-    it 'renders json in a correct format' do
-      post :preview_markdown, params: { namespace_id: project.namespace, project_id: project, id: 'page/path', text: '*Markdown* text' }
-
-      expect(json_response.keys).to match_array(%w(body references))
-    end
-  end
-
-  describe 'GET #edit' do
-    subject { get(:edit, params: { namespace_id: project.namespace, project_id: project, id: wiki_title }) }
-
-    context 'when page content encoding is invalid' do
-      it 'redirects to show' do
-        allow(controller).to receive(:valid_encoding?).and_return(false)
-
-        subject
-
-        expect(response).to redirect_to(project_wiki_path(project, project_wiki.list_pages.first))
-      end
-    end
-
-    context 'when page content encoding is valid' do
-      render_views
-
-      it 'shows the edit page' do
-        subject
-
-        expect(response).to have_http_status(:ok)
-        expect(response.body).to include('Edit Page')
-      end
-    end
-  end
-
-  describe 'PATCH #update' do
-    let(:new_title) { 'New title' }
-    let(:new_content) { 'New content' }
-    subject do
-      patch(:update,
-            params: {
-              namespace_id: project.namespace,
-              project_id: project,
-              id: wiki_title,
-              wiki: { title: new_title, content: new_content }
-            })
-    end
-
-    context 'when page content encoding is invalid' do
-      it 'redirects to show' do
-        allow(controller).to receive(:valid_encoding?).and_return(false)
-
-        subject
-        expect(response).to redirect_to(project_wiki_path(project, project_wiki.list_pages.first))
-      end
-    end
-
-    context 'when page content encoding is valid' do
-      render_views
-
-      it 'updates the page' do
-        subject
-
-        wiki_page = project_wiki.list_pages(load_content: true).first
-
-        expect(wiki_page.title).to eq new_title
-        expect(wiki_page.content).to eq new_content
-      end
-    end
+    include_examples 'sorting-and-nesting', ProjectWiki::CREATED_AT_ORDER, ProjectWiki::NESTING_FLAT
+    include_examples 'sorting-and-nesting', ProjectWiki::TITLE_ORDER, ProjectWiki::NESTING_CLOSED
   end
 
   def create_page(name, content)

spec/factories/wiki_pages.rb

@@ -18,12 +18,12 @@ FactoryBot.define do
     association :wiki, factory: :project_wiki, strategy: :build
     initialize_with { new(wiki, page, true) }
 
-    before(:create) do |page, evaluator|
-      page.attributes = evaluator.attrs
+    before(:create) do |wiki_page, evaluator|
+      wiki_page.attributes = evaluator.attrs.with_indifferent_access
     end
 
-    to_create do |page|
-      page.create
+    to_create do |wiki_page|
+      wiki_page.create
     end
   end
 end

spec/features/projects/features_visibility_spec.rb

@@ -3,8 +3,9 @@
 require 'spec_helper'
 
 describe 'Edit Project Settings' do
+  set(:project) { create(:project, :public, :repository) }
+
   let(:member) { create(:user) }
-  let!(:project) { create(:project, :public, :repository) }
   let!(:issue) { create(:issue, project: project) }
   let(:non_member) { create(:user) }
 
@@ -81,49 +82,52 @@ describe 'Edit Project Settings' do
   end
 
   describe 'project features visibility pages' do
-    let(:pipeline) { create(:ci_empty_pipeline, project: project) }
-    let(:job) { create(:ci_build, pipeline: pipeline) }
+    set(:pipeline) { create(:ci_empty_pipeline, project: project) }
+    set(:job) { create(:ci_build, pipeline: pipeline) }
 
-    let(:tools) do
-      {
-        builds: project_job_path(project, job),
-        issues: project_issues_path(project),
-        wiki: project_wiki_path(project, :home),
-        snippets: project_snippets_path(project),
-        merge_requests: project_merge_requests_path(project)
-      }
+    where(:method_name, :build_url) do
+      [
+        [:builds,         -> { project_job_path(project, job) }],
+        [:issues,         -> { project_issues_path(project) }],
+        [:wiki,           -> { project_wiki_path(project, :home) }],
+        [:snippets,       -> { project_snippets_path(project) }],
+        [:merge_requests, -> { project_merge_requests_path(project) }]
+      ]
     end
 
+    with_them do
+      let(:url) { build_url.call }
+      let(:attr_name) { "#{method_name}_access_level" }
+
       context 'normal user' do
         before do
+          project.team.truncate
           sign_in(member)
         end
 
         it 'renders 200 if tool is enabled' do
-        tools.each do |method_name, url|
-          project.project_feature.update_attribute("#{method_name}_access_level", ProjectFeature::ENABLED)
+          project.project_feature.update_attribute(attr_name, ProjectFeature::ENABLED)
+
           visit url
+
           expect(page.status_code).to eq(200)
         end
-      end
 
         it 'renders 404 if feature is disabled' do
-        tools.each do |method_name, url|
-          project.project_feature.update_attribute("#{method_name}_access_level", ProjectFeature::DISABLED)
+          project.project_feature.update_attribute(attr_name, ProjectFeature::DISABLED)
+
           visit url
+
           expect(page.status_code).to eq(404)
         end
-      end
 
         it 'renders 404 if feature is enabled only for team members' do
-        project.team.truncate
+          project.project_feature.update_attribute(attr_name, ProjectFeature::PRIVATE)
 
-        tools.each do |method_name, url|
-          project.project_feature.update_attribute("#{method_name}_access_level", ProjectFeature::PRIVATE)
           visit url
+
           expect(page.status_code).to eq(404)
         end
-      end
 
         it 'renders 200 if user is member of group' do
           group = create(:group)
@@ -132,34 +136,34 @@ describe 'Edit Project Settings' do
 
           group.add_owner(member)
 
-        tools.each do |method_name, url|
-          project.project_feature.update_attribute("#{method_name}_access_level", ProjectFeature::PRIVATE)
+          project.project_feature.update_attribute(attr_name, ProjectFeature::PRIVATE)
+
           visit url
+
           expect(page.status_code).to eq(200)
         end
       end
-    end
 
       context 'admin user' do
         before do
           non_member.update_attribute(:admin, true)
+          project.team.truncate
           sign_in(non_member)
         end
 
         it 'renders 404 if feature is disabled' do
-        tools.each do |method_name, url|
           project.project_feature.update_attribute("#{method_name}_access_level", ProjectFeature::DISABLED)
+
           visit url
+
           expect(page.status_code).to eq(404)
         end
-      end
 
         it 'renders 200 if feature is enabled only for team members' do
-        project.team.truncate
-
-        tools.each do |method_name, url|
           project.project_feature.update_attribute("#{method_name}_access_level", ProjectFeature::PRIVATE)
+
           visit url
+
           expect(page.status_code).to eq(200)
         end
       end

spec/features/projects/wiki/markdown_preview_spec.rb

@@ -4,164 +4,54 @@ require 'spec_helper'
 
 describe 'Projects > Wiki > User previews markdown changes', :js do
   set(:user) { create(:user) }
-  let(:project) { create(:project, :wiki_repo, namespace: user.namespace) }
-  let(:wiki_page) { create(:wiki_page, wiki: project.wiki, attrs: { title: 'home', content: '[some link](other-page)' }) }
-  let(:wiki_content) do
-    <<-HEREDOC
-[regular link](regular)
-[relative link 1](../relative)
-[relative link 2](./relative)
-[relative link 3](./e/f/relative)
-[spaced link](title with spaces)
-    HEREDOC
-  end
+  set(:project) { create(:project, :wiki_repo, namespace: user.namespace) }
+  let(:project_wiki) { ProjectWiki.new(project, user) }
 
   before do
     project.add_maintainer(user)
-
     sign_in(user)
+    init_home!
   end
 
-  context "while creating a new wiki page" do
-    context "when there are no spaces or hyphens in the page name" do
-      it "rewrites relative links as expected" do
-        create_wiki_page('a/b/c/d', content: wiki_content)
-
-        expect(page).to have_content("regular link")
-
-        expect(page.html).to include("<a href=\"/#{project.full_path}/wikis/regular\">regular link</a>")
-        expect(page.html).to include("<a href=\"/#{project.full_path}/wikis/a/b/relative\">relative link 1</a>")
-        expect(page.html).to include("<a href=\"/#{project.full_path}/wikis/a/b/c/relative\">relative link 2</a>")
-        expect(page.html).to include("<a href=\"/#{project.full_path}/wikis/a/b/c/e/f/relative\">relative link 3</a>")
-        expect(page.html).to include("<a href=\"/#{project.full_path}/wikis/title%20with%20spaces\">spaced link</a>")
-      end
-    end
-
-    context "when there are spaces in the page name" do
-      it "rewrites relative links as expected" do
-        create_wiki_page('a page/b page/c page/d page', content: wiki_content)
-
-        expect(page).to have_content("regular link")
-
-        expect(page.html).to include("<a href=\"/#{project.full_path}/wikis/regular\">regular link</a>")
-        expect(page.html).to include("<a href=\"/#{project.full_path}/wikis/a-page/b-page/relative\">relative link 1</a>")
-        expect(page.html).to include("<a href=\"/#{project.full_path}/wikis/a-page/b-page/c-page/relative\">relative link 2</a>")
-        expect(page.html).to include("<a href=\"/#{project.full_path}/wikis/a-page/b-page/c-page/e/f/relative\">relative link 3</a>")
-        expect(page.html).to include("<a href=\"/#{project.full_path}/wikis/title%20with%20spaces\">spaced link</a>")
+  def init_home!
+    create(:wiki_page, wiki: project.wiki, attrs: { title: 'home', content: '[some link](other-page)' })
   end
-    end
-
-    context "when there are hyphens in the page name" do
-      it "rewrites relative links as expected" do
-        create_wiki_page('a-page/b-page/c-page/d-page', content: wiki_content)
-
-        expect(page).to have_content("regular link")
 
-        expect(page.html).to include("<a href=\"/#{project.full_path}/wikis/regular\">regular link</a>")
-        expect(page.html).to include("<a href=\"/#{project.full_path}/wikis/a-page/b-page/relative\">relative link 1</a>")
-        expect(page.html).to include("<a href=\"/#{project.full_path}/wikis/a-page/b-page/c-page/relative\">relative link 2</a>")
-        expect(page.html).to include("<a href=\"/#{project.full_path}/wikis/a-page/b-page/c-page/e/f/relative\">relative link 3</a>")
-        expect(page.html).to include("<a href=\"/#{project.full_path}/wikis/title%20with%20spaces\">spaced link</a>")
+  def fill_in_content!
+    page.within '.wiki-form' do
+      fill_in :wiki_page_content, with: wiki_content
     end
   end
-  end
-
-  context "while editing a wiki page" do
-    context "when there are no spaces or hyphens in the page name" do
-      it "rewrites relative links as expected" do
-        create_wiki_page('a/b/c/d')
-        click_link 'Edit'
 
-        fill_in :wiki_content, with: wiki_content
-        click_on "Preview"
-
-        expect(page).to have_content("regular link")
-
-        expect(page.html).to include("<a href=\"/#{project.full_path}/wikis/regular\">regular link</a>")
-        expect(page.html).to include("<a href=\"/#{project.full_path}/wikis/a/b/relative\">relative link 1</a>")
-        expect(page.html).to include("<a href=\"/#{project.full_path}/wikis/a/b/c/relative\">relative link 2</a>")
-        expect(page.html).to include("<a href=\"/#{project.full_path}/wikis/a/b/c/e/f/relative\">relative link 3</a>")
-        expect(page.html).to include("<a href=\"/#{project.full_path}/wikis/title%20with%20spaces\">spaced link</a>")
+  def show_preview!
+    page.within '.wiki-form' do
+      click_on 'Preview'
     end
   end
 
-    context "when there are spaces in the page name" do
-      it "rewrites relative links as expected" do
-        create_wiki_page('a page/b page/c page/d page')
-        click_link 'Edit'
+  context 'when writing a new page' do
+    let(:new_wiki_path) { 'a/b/c/d' }
+    let(:wiki_content) { 'Some [awesome wiki](content)' }
 
-        fill_in :wiki_content, with: wiki_content
-        click_on "Preview"
+    it 'can show a preview of markdown content' do
+      visit project_wiki_pages_new_path(project, id: new_wiki_path)
+      fill_in_content!
+      show_preview!
 
-        expect(page).to have_content("regular link")
-
-        expect(page.html).to include("<a href=\"/#{project.full_path}/wikis/regular\">regular link</a>")
-        expect(page.html).to include("<a href=\"/#{project.full_path}/wikis/a-page/b-page/relative\">relative link 1</a>")
-        expect(page.html).to include("<a href=\"/#{project.full_path}/wikis/a-page/b-page/c-page/relative\">relative link 2</a>")
-        expect(page.html).to include("<a href=\"/#{project.full_path}/wikis/a-page/b-page/c-page/e/f/relative\">relative link 3</a>")
-        expect(page.html).to include("<a href=\"/#{project.full_path}/wikis/title%20with%20spaces\">spaced link</a>")
+      expect(page).to have_link('awesome wiki')
     end
   end
 
-    context "when there are hyphens in the page name" do
-      it "rewrites relative links as expected" do
-        create_wiki_page('a-page/b-page/c-page/d-page')
-        click_link 'Edit'
-
-        fill_in :wiki_content, with: wiki_content
-        click_on "Preview"
+  context 'when editing an existing page' do
+    let(:wiki_content) { 'Some [bemusing](content)' }
+    let(:wiki_page) { create(:wiki_page, wiki: project_wiki) }
 
-        expect(page).to have_content("regular link")
+    it 'can show a preview of markdown content, when writing' do
+      visit project_wiki_edit_path(project, wiki_page)
+      fill_in_content!
+      show_preview!
 
-        expect(page.html).to include("<a href=\"/#{project.full_path}/wikis/regular\">regular link</a>")
-        expect(page.html).to include("<a href=\"/#{project.full_path}/wikis/a-page/b-page/relative\">relative link 1</a>")
-        expect(page.html).to include("<a href=\"/#{project.full_path}/wikis/a-page/b-page/c-page/relative\">relative link 2</a>")
-        expect(page.html).to include("<a href=\"/#{project.full_path}/wikis/a-page/b-page/c-page/e/f/relative\">relative link 3</a>")
-        expect(page.html).to include("<a href=\"/#{project.full_path}/wikis/title%20with%20spaces\">spaced link</a>")
+      expect(page).to have_link('bemusing')
     end
   end
-
-    context 'when rendering the preview' do
-      it 'renders content with CommonMark' do
-        create_wiki_page('a-page/b-page/c-page/common-mark')
-        click_link 'Edit'
-
-        fill_in :wiki_content, with: "1. one\n  - sublist\n"
-        click_on "Preview"
-
-        # the above generates two separate lists (not embedded) in CommonMark
-        expect(page).to have_content("sublist")
-        expect(page).not_to have_xpath("//ol//li//ul")
-      end
-    end
-  end
-
-  it "does not linkify double brackets inside code blocks as expected" do
-    wiki_content = <<-HEREDOC
-      `[[do_not_linkify]]`
-      ```
-      [[also_do_not_linkify]]
-      ```
-    HEREDOC
-
-    create_wiki_page('linkify_test', wiki_content)
-
-    expect(page).to have_content("do_not_linkify")
-
-    expect(page.html).to include('[[do_not_linkify]]')
-    expect(page.html).to include('[[also_do_not_linkify]]')
-  end
-
-  private
-
-  def create_wiki_page(path, content = 'content')
-    visit project_wiki_path(project, wiki_page)
-
-    click_link 'New page'
-
-    fill_in :wiki_title, with: path
-    fill_in :wiki_content, with: content
-
-    click_button 'Create page'
-  end
 end

spec/features/projects/wiki/user_deletes_wiki_page_spec.rb

@@ -6,6 +6,7 @@ describe 'User deletes wiki page', :js do
   let(:user) { create(:user) }
   let(:project) { create(:project, :wiki_repo, namespace: user.namespace) }
   let(:wiki_page) { create(:wiki_page, wiki: project.wiki) }
+  let(:project_wiki) { ProjectWiki.new(project, user) }
 
   before do
     sign_in(user)
@@ -18,5 +19,6 @@ describe 'User deletes wiki page', :js do
     find('.modal-footer .btn-danger').click
 
     expect(page).to have_content('Page was successfully deleted')
+    expect(project_wiki.find_page(wiki_page.slug)).to be nil
   end
 end

spec/features/projects/wiki/user_updates_wiki_page_spec.rb

@@ -10,6 +10,13 @@ describe 'User updates wiki page' do
     sign_in(user)
   end
 
+  def create_page(attrs = {})
+    page.within('.wiki-form') do
+      attrs.each { |k, v| fill_in("wiki_page_#{k}".to_sym, with: v) }
+      click_on('Create page')
+    end
+  end
+
   context 'when wiki is empty' do
     before do
       visit(project_wikis_path(project))
@@ -28,12 +35,7 @@ describe 'User updates wiki page' do
       end
 
       it 'updates a page that has a path', :js do
-        fill_in(:wiki_title, with: 'one/two/three-test')
-
-        page.within '.wiki-form' do
-          fill_in(:wiki_content, with: 'wiki content')
-          click_on('Create page')
-        end
+        create_page(title: 'one/two/three-test', content: 'wiki content')
 
         expect(current_path).to include('one/two/three-test')
         expect(find('.wiki-pages')).to have_content('three')
@@ -72,9 +74,9 @@ describe 'User updates wiki page' do
 
       it 'updates a page', :js do
         # Commit message field should have correct value.
-        expect(page).to have_field('wiki[message]', with: 'Update home')
+        expect(page).to have_field('wiki_page[message]', with: 'Update home')
 
-        fill_in(:wiki_content, with: 'My awesome wiki!')
+        fill_in(:wiki_page_content, with: 'My awesome wiki!')
         click_button('Save changes')
 
         expect(page).to have_content('Home')
@@ -83,31 +85,31 @@ describe 'User updates wiki page' do
       end
 
       it 'updates the commit message as the title is changed', :js do
-        fill_in(:wiki_title, with: 'Wiki title')
+        fill_in(:wiki_page_title, with: 'Wiki title')
 
-        expect(page).to have_field('wiki[message]', with: 'Update Wiki title')
+        expect(page).to have_field('wiki_page[message]', with: 'Update Wiki title')
       end
 
       it 'does not allow XSS', :js do
-        fill_in(:wiki_title, with: '<script>')
+        fill_in(:wiki_page_title, with: '<script>')
 
-        expect(page).to have_field('wiki[message]', with: 'Update &lt;script&gt;')
+        expect(page).to have_field('wiki_page[message]', with: 'Update &lt;script&gt;')
       end
 
       it 'shows a validation error message' do
-        fill_in(:wiki_content, with: '')
+        fill_in(:wiki_page_content, with: '')
         click_button('Save changes')
 
         expect(page).to have_selector('.wiki-form')
         expect(page).to have_content('Edit Page')
         expect(page).to have_content('The form contains the following error:')
         expect(page).to have_content("Content can't be blank")
-        expect(find('textarea#wiki_content').value).to eq('')
+        expect(find('textarea#wiki_page_content').value).to eq('')
       end
 
       it 'shows the emoji autocompletion dropdown', :js do
-        find('#wiki_content').native.send_keys('')
-        fill_in(:wiki_content, with: ':')
+        find('#wiki_page_content').native.send_keys('')
+        fill_in(:wiki_page_content, with: ':')
 
         expect(page).to have_selector('.atwho-view')
       end
@@ -143,9 +145,9 @@ describe 'User updates wiki page' do
 
       it 'updates a page', :js do
         # Commit message field should have correct value.
-        expect(page).to have_field('wiki[message]', with: 'Update home')
+        expect(page).to have_field('wiki_page[message]', with: 'Update home')
 
-        fill_in(:wiki_content, with: 'My awesome wiki!')
+        fill_in(:wiki_page_content, with: 'My awesome wiki!')
 
         click_button('Save changes')
 
@@ -169,50 +171,43 @@ describe 'User updates wiki page' do
       visit(project_wiki_edit_path(project, wiki_page))
     end
 
-    it 'moves the page to the root folder' do
-      fill_in(:wiki_title, with: "/#{page_name}")
+    def edit_title!(title)
+      fill_in(:wiki_page_title, with: title)
 
       click_button('Save changes')
+    end
+
+    it 'moves the page to the root folder' do
+      edit_title!("/#{page_name}")
 
       expect(current_path).to eq(project_wiki_path(project, page_name))
     end
 
     it 'moves the page to other dir' do
-      new_page_dir = "foo1/bar1/#{page_name}"
-
-      fill_in(:wiki_title, with: new_page_dir)
+      new_page_path = "baz/quux/#{page_name}"
+      edit_title!(new_page_path)
 
-      click_button('Save changes')
-
-      expect(current_path).to eq(project_wiki_path(project, new_page_dir))
+      expect(current_path).to eq(project_wiki_path(project, new_page_path))
     end
 
     it 'remains in the same place if title has not changed' do
       original_path = project_wiki_path(project, wiki_page)
-
-      fill_in(:wiki_title, with: page_name)
-
-      click_button('Save changes')
+      edit_title!(page_name)
 
       expect(current_path).to eq(original_path)
     end
 
     it 'can be moved to a different dir with a different name' do
-      new_page_dir = "foo1/bar1/new_page_name"
-
-      fill_in(:wiki_title, with: new_page_dir)
+      new_page_path = "quux/baz/new_page_name"
+      edit_title!(new_page_path)
 
-      click_button('Save changes')
-
-      expect(current_path).to eq(project_wiki_path(project, new_page_dir))
+      expect(current_path).to eq(project_wiki_path(project, new_page_path))
     end
 
     it 'can be renamed and moved to the root folder' do
       new_name = 'new_page_name'
 
-      fill_in(:wiki_title, with: "/#{new_name}")
-
-      click_button('Save changes')
+      edit_title!("/#{new_name}")
 
       expect(current_path).to eq(project_wiki_path(project, new_name))
     end
@@ -220,9 +215,7 @@ describe 'User updates wiki page' do
     it 'squishes the title before creating the page' do
       new_page_dir = "  foo1 /  bar1  /  #{page_name}  "
 
-      fill_in(:wiki_title, with: new_page_dir)
-
-      click_button('Save changes')
+      edit_title!(new_page_dir)
 
       expect(current_path).to eq(project_wiki_path(project, "foo1/bar1/#{page_name}"))
     end

spec/features/projects/wiki/user_views_wiki_page_spec.rb

@@ -8,10 +8,11 @@ describe 'User views a wiki page' do
   let(:user) { create(:user) }
   let(:project) { create(:project, :wiki_repo, namespace: user.namespace) }
   let(:path) { 'image.png' }
+  let(:wiki_content) { "Look at this [image](#{path})\n\n ![alt text](#{path})" }
   let(:wiki_page) do
     create(:wiki_page,
            wiki: project.wiki,
-           attrs: { title: 'home', content: "Look at this [image](#{path})\n\n ![alt text](#{path})" })
+           attrs: { title: 'home', content: wiki_content })
   end
 
   before do
@@ -19,17 +20,18 @@ describe 'User views a wiki page' do
     sign_in(user)
   end
 
+  def create_page(attrs = {})
+    page.within('.wiki-form') do
+      attrs.each { |k, v| fill_in("wiki_page_#{k}".to_sym, with: v) }
+      click_on('Create page')
+    end
+  end
+
   context 'when wiki is empty' do
     before do
       visit(project_wikis_path(project))
       click_link "Create your first page"
-
-      fill_in(:wiki_title, with: 'one/two/three-test')
-
-      page.within('.wiki-form') do
-        fill_in(:wiki_content, with: 'wiki content')
-        click_on('Create page')
-      end
+      create_page(title: 'one/two/three-test', content: 'wiki content')
     end
 
     it 'shows the history of a page that has a path', :js do
@@ -83,24 +85,27 @@ describe 'User views a wiki page' do
 
     context 'shows a file stored in a page' do
       let(:path) { upload_file_to_wiki(project, user, 'dk.png') }
+      let(:image_path) { project_wiki_path(project, path) }
 
       it do
-        expect(page).to have_xpath("//img[@data-src='#{project.wiki.wiki_base_path}/#{path}']")
-        expect(page).to have_link('image', href: "#{project.wiki.wiki_base_path}/#{path}")
+        expect(page).to have_xpath("//img[@data-src='#{image_path}']")
+        expect(page).to have_link('image', href: "#{image_path}")
 
         click_on('image')
 
-        expect(current_path).to match("wikis/#{path}")
+        expect(current_path).to match(path)
         expect(page).not_to have_xpath('/html') # Page should render the image which means there is no html involved
       end
     end
 
     it 'shows the creation page if file does not exist' do
-      expect(page).to have_link('image', href: "#{project.wiki.wiki_base_path}/#{path}")
+      href = project_wiki_path(project, path)
+
+      expect(page).to have_link('image', href: href)
 
       click_on('image')
 
-      expect(current_path).to match("wikis/#{path}")
+      expect(current_path).to match(href)
       expect(page).to have_content('Create New Page')
     end
   end

spec/features/projects/wiki/user_views_wiki_pages_spec.rb

@@ -7,6 +7,7 @@ describe 'User views wiki pages' do
 
   let(:user) { create(:user) }
   let(:project) { create(:project, :wiki_repo, namespace: user.namespace) }
+  let(:project_wiki) { ProjectWiki.new(project, user) }
 
   let!(:wiki_page1) do
     create(:wiki_page, wiki: project.wiki, attrs: { title: '3 home', content: '3' })
@@ -17,73 +18,182 @@ describe 'User views wiki pages' do
   let!(:wiki_page3) do
     create(:wiki_page, wiki: project.wiki, attrs: { title: '2 home', content: '2' })
   end
+  let!(:wiki_page4) do
+    create(:wiki_page, wiki: project.wiki, attrs: { title: 'sub-folder/0', content: 'a' })
+  end
+  let!(:wiki_page5) do
+    create(:wiki_page, wiki: project.wiki, attrs: { title: 'sub-folder/b', content: 'b' })
+  end
+
+  let(:page_link_selector) { 'a' }
 
   let(:pages) do
-    page.find('.wiki-pages-list').all('li').map { |li| li.find('a') }
+    page.all(".wiki-pages-list li #{page_link_selector}")
   end
+  let(:wikis_allow_change_nesting) { false }
 
   before do
+    stub_feature_flags(wikis_allow_change_nesting: wikis_allow_change_nesting)
     project.add_maintainer(user)
     sign_in(user)
     visit(project_wikis_pages_path(project))
   end
 
-  context 'ordered by title' do
-    let(:pages_ordered_by_title) { [wiki_page2, wiki_page3, wiki_page1] }
+  def sort_desc!
+    page.within('.wiki-sort-dropdown') do
+      page.find('.qa-reverse-sort').click
+    end
+  end
 
-    context 'asc' do
-      it 'pages are displayed in direct order' do
-        pages.each.with_index do |page_title, index|
-          expect(page_title.text).to eq(pages_ordered_by_title[index].title)
+  def sort_by_created_at!
+    page.within('.wiki-sort-dropdown') do
+      click_button('Title')
+      click_link('Created date')
+    end
   end
+
+  shared_examples 'correctly_sorted_pages' do
+    it 'has pages displayed in correct order' do
+      displayed_texts = pages.map(&:text)
+      expect(displayed_texts).to eq expected_sequence.map(&:title)
     end
   end
 
+  context 'ordered by title' do
+    let(:sub_folder) { project_wiki.find_dir('sub-folder') }
+
+    context 'default display settings' do
+      context 'asc' do
+        let(:expected_sequence) { [wiki_page2, wiki_page3, wiki_page1, sub_folder] }
+
+        it_behaves_like 'correctly_sorted_pages'
+      end
+
       context 'desc' do
         before do
-        page.within('.wiki-sort-dropdown') do
-          page.find('.rspec-reverse-sort').click
+          sort_desc!
+        end
+
+        let(:expected_sequence) { [sub_folder, wiki_page1, wiki_page3, wiki_page2] }
+
+        it_behaves_like 'correctly_sorted_pages'
       end
     end
 
-      it 'pages are displayed in reversed order' do
-        pages.reverse_each.with_index do |page_title, index|
-          expect(page_title.text).to eq(pages_ordered_by_title[index].title)
+    context 'changing nesting is disabled' do
+      let(:wikis_allow_change_nesting) { false }
+
+      it 'does not display a nesting controller' do
+        expect(page).not_to have_css('.wiki-nesting-dropdown')
+      end
     end
+
+    context 'changing nesting is enabled' do
+      let(:wikis_allow_change_nesting) { true }
+
+      it 'displays a nesting controller' do
+        expect(page).to have_css('.wiki-nesting-dropdown')
       end
+
+      context 'tree' do
+        before do
+          page.within('.wiki-nesting-dropdown') do
+            click_link 'Show folder contents'
           end
         end
 
-  context 'ordered by created_at' do
-    let(:pages_ordered_by_created_at) { [wiki_page1, wiki_page2, wiki_page3] }
+        context 'asc' do
+          let(:expected_sequence) { [wiki_page2, wiki_page3, wiki_page1, sub_folder, wiki_page4, wiki_page5] }
+
+          it_behaves_like 'correctly_sorted_pages'
+        end
 
+        context 'desc' do
           before do
-      page.within('.wiki-sort-dropdown') do
-        click_button('Title')
-        click_link('Created date')
+            sort_desc!
+          end
+
+          let(:expected_sequence) { [sub_folder, wiki_page5, wiki_page4, wiki_page1, wiki_page3, wiki_page2] }
+
+          it_behaves_like 'correctly_sorted_pages'
+        end
+      end
+
+      context 'nested' do
+        before do
+          page.within('.wiki-nesting-dropdown') do
+            click_link 'Hide folder contents'
           end
         end
 
         context 'asc' do
-      it 'pages are displayed in direct order' do
-        pages.each.with_index do |page_title, index|
-          expect(page_title.text).to eq(pages_ordered_by_created_at[index].title)
+          let(:expected_sequence) { [wiki_page2, wiki_page3, wiki_page1, sub_folder] }
+
+          it_behaves_like 'correctly_sorted_pages'
+        end
+
+        context 'desc' do
+          before do
+            sort_desc!
+          end
+
+          let(:expected_sequence) { [sub_folder, wiki_page1, wiki_page3, wiki_page2] }
+
+          it_behaves_like 'correctly_sorted_pages'
+        end
+      end
+
+      context 'flat' do
+        before do
+          page.within('.wiki-nesting-dropdown') do
+            click_link 'Show files separately'
           end
         end
+
+        let(:page_link_selector) { 'a.wiki-page-title' }
+
+        context 'asc' do
+          let(:expected_sequence) { [wiki_page2, wiki_page3, wiki_page1, wiki_page4, wiki_page5] }
+
+          it_behaves_like 'correctly_sorted_pages'
         end
 
         context 'desc' do
           before do
-        page.within('.wiki-sort-dropdown') do
-          page.find('.rspec-reverse-sort').click
+            sort_desc!
+          end
+
+          let(:expected_sequence) { [wiki_page5, wiki_page4, wiki_page1, wiki_page3, wiki_page2] }
+
+          it_behaves_like 'correctly_sorted_pages'
+        end
       end
     end
+  end
+
+  context 'ordered by created_at' do
+    let(:pages_ordered_by_created_at) { [wiki_page1, wiki_page2, wiki_page3, wiki_page4, wiki_page5] }
 
-      it 'pages are displayed in reversed order' do
-        pages.reverse_each.with_index do |page_title, index|
-          expect(page_title.text).to eq(pages_ordered_by_created_at[index].title)
+    before do
+      sort_by_created_at!
     end
+
+    let(:page_link_selector) { 'a.wiki-page-title' }
+
+    context 'asc' do
+      let(:expected_sequence) { [wiki_page1, wiki_page2, wiki_page3, wiki_page4, wiki_page5] }
+
+      it_behaves_like 'correctly_sorted_pages'
     end
+
+    context 'desc' do
+      before do
+        sort_desc!
+      end
+
+      let(:expected_sequence) { [wiki_page5, wiki_page4, wiki_page3, wiki_page2, wiki_page1] }
+
+      it_behaves_like 'correctly_sorted_pages'
     end
   end
 end

spec/frontend/wikis_spec.js

@@ -3,27 +3,27 @@ import { setHTMLFixture } from './helpers/fixtures';
 
 describe('Wikis', () => {
   describe('setting the commit message when the title changes', () => {
-    const editFormHtmlFixture = args => `<form class="wiki-form ${
-      args.newPage ? 'js-new-wiki-page' : ''
-    }">
-        <input type="text" id="wiki_title" value="My title" />
-        <input type="text" id="wiki_message" />
-      </form>`;
-
     let wikis;
     let titleInput;
     let messageInput;
+    const CREATE = true;
+    const UPDATE = false;
 
-    describe('when the wiki page is being created', () => {
-      const formHtmlFixture = editFormHtmlFixture({ newPage: true });
-
-      beforeEach(() => {
-        setHTMLFixture(formHtmlFixture);
+    const editFormHtmlFixture = newPage =>
+      `<form class="wiki-form ${newPage ? 'js-new-wiki-page' : ''}">
+        <input type="text" id="wiki_page_title" value="My title" />
+        <input type="text" id="wiki_page_message" />
+      </form>`;
 
-        titleInput = document.getElementById('wiki_title');
-        messageInput = document.getElementById('wiki_message');
+    const init = newPage => {
+      setHTMLFixture(editFormHtmlFixture(newPage));
+      titleInput = document.getElementById('wiki_page_title');
+      messageInput = document.getElementById('wiki_page_message');
       wikis = new Wikis();
-      });
+    };
+
+    describe('when the wiki page is being created', () => {
+      beforeEach(() => init(CREATE));
 
       it('binds an event listener to the title input', () => {
         wikis.handleWikiTitleChange = jest.fn();
@@ -51,15 +51,7 @@ describe('Wikis', () => {
     });
 
     describe('when the wiki page is being updated', () => {
-      const formHtmlFixture = editFormHtmlFixture({ newPage: false });
-
-      beforeEach(() => {
-        setHTMLFixture(formHtmlFixture);
-
-        titleInput = document.getElementById('wiki_title');
-        messageInput = document.getElementById('wiki_message');
-        wikis = new Wikis();
-      });
+      beforeEach(() => init(UPDATE));
 
       it('sets the commit message when title changes, prefixing with "Update"', () => {
         titleInput.value = 'My title';

spec/helpers/wiki_helper_spec.rb

@@ -23,8 +23,13 @@ describe WikiHelper do
 
   describe '#wiki_sort_controls' do
     let(:project) { create(:project) }
-    let(:wiki_link) { helper.wiki_sort_controls(project, sort, direction) }
-    let(:classes) { "btn btn-default has-tooltip reverse-sort-btn qa-reverse-sort rspec-reverse-sort" }
+    let(:classes) { described_class::WIKI_SORT_CSS_CLASSES }
+
+    subject(:wiki_link) do
+      helper.wiki_sort_controls(sort: sort, direction: direction) do |opts|
+        project_wikis_pages_path(project, opts)
+      end
+    end
 
     def expected_link(sort, direction, icon_class)
       path = "/#{project.full_path}/wikis/pages?direction=#{direction}&sort=#{sort}"
@@ -62,6 +67,18 @@ describe WikiHelper do
     end
   end
 
+  describe '#wiki_show_children_icon' do
+    ProjectWiki::NESTINGS.each do |nesting|
+      context "When the nesting parameter is `#{nesting}`" do
+        let(:element) { helper.wiki_show_children_icon(nesting) }
+
+        it 'produces something that contains an SVG' do
+          expect(element).to match(/svg/)
+        end
+      end
+    end
+  end
+
   describe '#wiki_sort_title' do
     it 'returns a title corresponding to a key' do
       expect(helper.wiki_sort_title('created_at')).to eq('Created date')

spec/lib/banzai/filter/wiki_link_filter_spec.rb

@@ -11,6 +11,10 @@ describe Banzai::Filter::WikiLinkFilter do
   let(:wiki) { ProjectWiki.new(project, user) }
   let(:repository_upload_folder) { Wikis::CreateAttachmentService::ATTACHMENT_PATH }
 
+  def upload_href(file_name)
+    ::File.join(wiki.wiki_page_path, repository_upload_folder, file_name)
+  end
+
   it "doesn't rewrite absolute links" do
     filtered_link = filter("<a href='http://example.com:8000/'>Link</a>", project_wiki: wiki).children[0]
 
@@ -28,12 +32,12 @@ describe Banzai::Filter::WikiLinkFilter do
       it 'rewrites links' do
         filtered_link = filter("<a href='#{repository_upload_folder}/a.test'>Link</a>", project_wiki: wiki).children[0]
 
-        expect(filtered_link.attribute('href').value).to eq("#{wiki.wiki_base_path}/#{repository_upload_folder}/a.test")
+        expect(filtered_link.attribute('href').value).to eq(upload_href "a.test")
       end
     end
 
     context 'with "img" html tag' do
-      let(:path) { "#{wiki.wiki_base_path}/#{repository_upload_folder}/a.jpg" }
+      let(:path) { upload_href "a.jpg" }
 
       context 'inside an "a" html tag' do
         it 'rewrites links' do
@@ -57,7 +61,7 @@ describe Banzai::Filter::WikiLinkFilter do
       it 'rewrites links' do
         filtered_link = filter("<video src='#{repository_upload_folder}/a.mp4'></video>", project_wiki: wiki).children[0]
 
-        expect(filtered_link.attribute('src').value).to eq("#{wiki.wiki_base_path}/#{repository_upload_folder}/a.mp4")
+        expect(filtered_link.attribute('src').value).to eq(upload_href "a.mp4")
       end
     end
 
@@ -65,7 +69,8 @@ describe Banzai::Filter::WikiLinkFilter do
       it 'rewrites links' do
         filtered_link = filter("<audio src='#{repository_upload_folder}/a.wav'></audio>", project_wiki: wiki).children[0]
 
-        expect(filtered_link.attribute('src').value).to eq("#{wiki.wiki_base_path}/#{repository_upload_folder}/a.wav")
+        # expect(filtered_link.attribute('src').value).to eq("#{wiki.wiki_base_path}/#{repository_upload_folder}/a.wav")
+        expect(filtered_link.attribute('src').value).to eq(upload_href "a.wav")
       end
     end
   end

spec/lib/gitlab/url_builder_spec.rb

@@ -150,7 +150,7 @@ describe Gitlab::UrlBuilder do
         wiki_page = build(:wiki_page)
         url = described_class.build(wiki_page)
 
-        expect(url).to eq "#{Gitlab.config.gitlab.url}#{wiki_page.wiki.wiki_base_path}/#{wiki_page.slug}"
+        expect(url).to eq "#{Gitlab.config.gitlab.url}#{wiki_page.wiki.wiki_page_path}/#{wiki_page.slug}"
       end
     end
   end

spec/lib/gitlab/utils_spec.rb

@@ -252,4 +252,41 @@ describe Gitlab::Utils do
       expect(described_class.string_to_ip_object('1:0:0:0:0:0:0:0/124')).to eq(IPAddr.new('1:0:0:0:0:0:0:0/124'))
     end
   end
+
+  describe '.allow_hash_values' do
+    it 'removes keys that do not pass the inclusion filters' do
+      symbols = %i[x y z]
+      ints = (0..100)
+      strings = %w[foo bar baz].to_set
+
+      hash = {
+        a: :x,
+        b: 100,
+        c: 'foo',
+        d: :irrelevant,
+        aa: :w,
+        bb: 200,
+        cc: 'food',
+        dd: :totally_irrelevant
+      }
+      allowed = {
+        a: symbols,
+        b: ints,
+        c: strings,
+        aa: symbols,
+        bb: ints,
+        cc: strings
+      }
+
+      described_class.allow_hash_values(hash, allowed)
+
+      expect(hash).to eq({
+        a: :x,
+        b: 100,
+        c: 'foo',
+        d: :irrelevant,
+        dd: :totally_irrelevant
+      })
+    end
+  end
 end

spec/models/project_wiki_spec.rb

@@ -28,7 +28,9 @@ describe ProjectWiki do
 
   describe '#web_url' do
     it 'returns the full web URL to the wiki' do
-      expect(subject.web_url).to eq("#{Gitlab.config.gitlab.url}/#{project.full_path}/wikis/home")
+      home_url = Gitlab::Routing.url_helpers.project_wiki_url(project, :home)
+
+      expect(subject.web_url).to eq(home_url)
     end
   end
 
@@ -71,9 +73,23 @@ describe ProjectWiki do
 
   describe "#wiki_base_path" do
     it "returns the wiki base path" do
-      wiki_base_path = "#{Gitlab.config.gitlab.relative_url_root}/#{project.full_path}/wikis"
+      wiki_path = Gitlab::Routing.url_helpers.project_wikis_path(project)
+
+      expect(subject.wiki_base_path).to eq(wiki_path)
+    end
+  end
 
-      expect(subject.wiki_base_path).to eq(wiki_base_path)
+  describe "#wiki_page_path" do
+    let(:page) { create(:wiki_page, wiki: project_wiki) }
+
+    describe 'suffixed with /:page_slug' do
+      subject { "#{project_wiki.wiki_page_path}/#{page.slug}" }
+
+      it "equals the project_wiki_path" do
+        path = Gitlab::Routing.url_helpers.project_wiki_path(project, page)
+
+        expect(subject).to eq(path)
+      end
     end
   end
 

spec/models/wiki_directory_spec.rb

 # frozen_string_literal: true
 
 require 'spec_helper'
+require 'set'
 
 RSpec.describe WikiDirectory do
+  include GitHelpers
+
+  let(:project) { create(:project, :wiki_repo) }
+  let(:user) { project.owner }
+  let(:wiki) { ProjectWiki.new(project, user) }
+
   describe 'validations' do
     subject { build(:wiki_directory) }
 
     it { is_expected.to validate_presence_of(:slug) }
   end
 
+  describe '.group_by_directory' do
+    context 'when there are no pages' do
+      it 'returns an empty array' do
+        expect(described_class.group_by_directory(nil)).to eq([])
+        expect(described_class.group_by_directory([])).to eq([])
+      end
+    end
+
+    context 'when there are pages' do
+      before do
+        create_page('dir_1/dir_1_1/page_3', 'content')
+        create_page('page_1', 'content')
+        create_page('dir_1/page_2', 'content')
+        create_page('dir_2', 'page with dir name')
+        create_page('dir_2/page_5', 'content')
+        create_page('page_6', 'content')
+        create_page('dir_2/page_4', 'content')
+      end
+
+      let(:page_1) { wiki.find_page('page_1') }
+      let(:page_6) { wiki.find_page('page_6') }
+      let(:page_dir_2) { wiki.find_page('dir_2') }
+
+      let(:dir_1) do
+        described_class.new('dir_1', [wiki.find_page('dir_1/page_2')])
+      end
+      let(:dir_1_1) do
+        described_class.new('dir_1/dir_1_1', [wiki.find_page('dir_1/dir_1_1/page_3')])
+      end
+      let(:dir_2) do
+        pages = [wiki.find_page('dir_2/page_5'),
+                 wiki.find_page('dir_2/page_4')]
+        described_class.new('dir_2', pages)
+      end
+
+      context "#list_pages" do
+        shared_examples "a correct grouping" do
+          let(:grouped_slugs) { grouped_entries.map(&method(:slugs)) }
+          let(:expected_slugs) { expected_grouped_entries.map(&method(:slugs)).map(&method(:match_array)) }
+
+          it 'returns an array with pages and directories' do
+            expect(grouped_slugs).to match_array(expected_slugs)
+          end
+        end
+
+        context 'sort by title' do
+          let(:grouped_entries) { described_class.group_by_directory(wiki.list_pages) }
+
+          let(:expected_grouped_entries) { [dir_1_1, dir_1, page_dir_2, dir_2, page_1, page_6] }
+
+          it_behaves_like "a correct grouping"
+        end
+
+        context 'sort by created_at' do
+          let(:grouped_entries) { described_class.group_by_directory(wiki.list_pages(sort: 'created_at')) }
+          let(:expected_grouped_entries) { [dir_1_1, page_1, dir_1, page_dir_2, dir_2, page_6] }
+
+          it_behaves_like "a correct grouping"
+        end
+
+        it 'returns an array with retained order with directories at the top' do
+          expected_order = ['dir_1/dir_1_1/page_3', 'dir_1/page_2', 'dir_2', 'dir_2/page_4', 'dir_2/page_5', 'page_1', 'page_6']
+
+          grouped_entries = described_class.group_by_directory(wiki.list_pages)
+
+          actual_order = grouped_entries.flat_map(&method(:slugs))
+
+          expect(actual_order).to eq(expected_order)
+        end
+      end
+    end
+  end
+
   describe '#initialize' do
     context 'when there are pages' do
       let(:pages) { [build(:wiki_page)] }
@@ -40,7 +120,112 @@ RSpec.describe WikiDirectory do
     it 'returns the relative path to the partial to be used' do
       directory = build(:wiki_directory)
 
-      expect(directory.to_partial_path).to eq('projects/wikis/wiki_directory')
+      expect(directory.to_partial_path).to eq('projects/wiki_directories/wiki_directory')
+    end
+  end
+
+  describe 'attributes' do
+    def page_path(index)
+      "dir-path/page-#{index}"
+    end
+
+    let(:page_paths) { (1..3).map { |n| page_path(n) } }
+
+    let(:pages) do
+      page_paths.map { |p| wiki.find_page(p) }
     end
+
+    subject { described_class.new('dir-path', pages) }
+
+    context 'there are no pages' do
+      let(:pages) { [] }
+
+      it { is_expected.to have_attributes(page_count: 0, last_version: be_nil) }
+    end
+
+    context 'there is one page' do
+      before do
+        create_page("dir-path/singleton", "Just this page")
+      end
+
+      let(:the_page) { wiki.find_page("dir-path/singleton") }
+      let(:pages) { [the_page] }
+
+      it { is_expected.to have_attributes(page_count: 1, last_version: the_page.last_version) }
+    end
+
+    context 'there are a few pages, each with a single version' do
+      before do
+        page_paths.each_with_index do |path, n|
+          Timecop.freeze(Time.local(1990) + n.minutes) do
+            create_page(path, "this is page #{n}")
+          end
+        end
+      end
+
+      let(:expected_last_version) { pages.last.last_version }
+
+      it { is_expected.to have_attributes(page_count: 3, last_version: expected_last_version) }
+    end
+
+    context 'there are a few pages, each with a few versions' do
+      before do
+        page_paths.each_with_index do |path, n|
+          t = Time.local(1990) + n.minutes
+          Timecop.freeze(t) do
+            create_page(path, "This is page #{n}")
+            (2..3).each do |v|
+              Timecop.freeze(t + v.seconds) do
+                update_page(path, "Now at version #{v}")
+              end
+            end
+          end
+        end
+      end
+
+      it { is_expected.to have_attributes(page_count: 3, last_version: pages.last.last_version) }
+    end
+  end
+
+  private
+
+  def create_page(name, content)
+    wiki.wiki.write_page(name, :markdown, content, commit_details)
+    set_time(name)
+  end
+
+  def update_page(name, content)
+    wiki.wiki.update_page(name, name, :markdown, content, update_commit_details)
+    set_time(name)
+  end
+
+  def set_time(name)
+    return unless Timecop.frozen?
+
+    new_date = Time.now
+    page = wiki.find_page(name).page
+    commit = page.version.commit
+    repo = commit.instance_variable_get(:@repository)
+
+    rug_commit = rugged_repo_at_path(repo.relative_path).lookup(commit.id)
+    rug_commit.amend(
+      message: rug_commit.message,
+      tree: rug_commit.tree,
+      author: rug_commit.author.merge(time: new_date),
+      committer: rug_commit.committer.merge(time: new_date),
+      update_ref: 'HEAD'
+    )
+  end
+
+  def commit_details
+    Gitlab::Git::Wiki::CommitDetails.new(user.id, user.username, user.name, user.email, "test commit")
+  end
+
+  def update_commit_details
+    Gitlab::Git::Wiki::CommitDetails.new(user.id, user.username, user.name, user.email, "test update")
+  end
+
+  def slugs(thing)
+    Array.wrap(thing.respond_to?(:pages) ? thing.pages.map(&:slug) : thing.slug)
   end
 end

spec/models/wiki_page_spec.rb

@@ -9,87 +9,6 @@ describe WikiPage do
 
   subject { described_class.new(wiki) }
 
-  describe '.group_by_directory' do
-    context 'when there are no pages' do
-      it 'returns an empty array' do
-        expect(described_class.group_by_directory(nil)).to eq([])
-        expect(described_class.group_by_directory([])).to eq([])
-      end
-    end
-
-    context 'when there are pages' do
-      before do
-        create_page('dir_1/dir_1_1/page_3', 'content')
-        create_page('page_1', 'content')
-        create_page('dir_1/page_2', 'content')
-        create_page('dir_2', 'page with dir name')
-        create_page('dir_2/page_5', 'content')
-        create_page('page_6', 'content')
-        create_page('dir_2/page_4', 'content')
-      end
-
-      let(:page_1) { wiki.find_page('page_1') }
-      let(:page_6) { wiki.find_page('page_6') }
-      let(:page_dir_2) { wiki.find_page('dir_2') }
-
-      let(:dir_1) do
-        WikiDirectory.new('dir_1', [wiki.find_page('dir_1/page_2')])
-      end
-      let(:dir_1_1) do
-        WikiDirectory.new('dir_1/dir_1_1', [wiki.find_page('dir_1/dir_1_1/page_3')])
-      end
-      let(:dir_2) do
-        pages = [wiki.find_page('dir_2/page_5'),
-                 wiki.find_page('dir_2/page_4')]
-        WikiDirectory.new('dir_2', pages)
-      end
-
-      context "#list_pages" do
-        context 'sort by title' do
-          let(:grouped_entries) { described_class.group_by_directory(wiki.list_pages) }
-          let(:expected_grouped_entries) { [dir_1_1, dir_1, page_dir_2, dir_2, page_1, page_6] }
-
-          it 'returns an array with pages and directories' do
-            grouped_entries.each_with_index do |page_or_dir, i|
-              expected_page_or_dir = expected_grouped_entries[i]
-              expected_slugs = get_slugs(expected_page_or_dir)
-              slugs = get_slugs(page_or_dir)
-
-              expect(slugs).to match_array(expected_slugs)
-            end
-          end
-        end
-
-        context 'sort by created_at' do
-          let(:grouped_entries) { described_class.group_by_directory(wiki.list_pages(sort: 'created_at')) }
-          let(:expected_grouped_entries) { [dir_1_1, page_1, dir_1, page_dir_2, dir_2, page_6] }
-
-          it 'returns an array with pages and directories' do
-            grouped_entries.each_with_index do |page_or_dir, i|
-              expected_page_or_dir = expected_grouped_entries[i]
-              expected_slugs = get_slugs(expected_page_or_dir)
-              slugs = get_slugs(page_or_dir)
-
-              expect(slugs).to match_array(expected_slugs)
-            end
-          end
-        end
-
-        it 'returns an array with retained order with directories at the top' do
-          expected_order = ['dir_1/dir_1_1/page_3', 'dir_1/page_2', 'dir_2', 'dir_2/page_4', 'dir_2/page_5', 'page_1', 'page_6']
-
-          grouped_entries = described_class.group_by_directory(wiki.list_pages)
-
-          actual_order =
-            grouped_entries.flat_map do |page_or_dir|
-              get_slugs(page_or_dir)
-            end
-          expect(actual_order).to eq(expected_order)
-        end
-      end
-    end
-  end
-
   describe '.unhyphenize' do
     it 'removes hyphens from a name' do
       name = 'a-name--with-hyphens'
@@ -505,7 +424,7 @@ describe WikiPage do
     it 'returns the relative path to the partial to be used' do
       page = build(:wiki_page)
 
-      expect(page.to_partial_path).to eq('projects/wikis/wiki_page')
+      expect(page.to_partial_path).to eq('projects/wiki_pages/wiki_page')
     end
   end
 
@@ -585,12 +504,4 @@ describe WikiPage do
     page = wiki.wiki.page(title: title, dir: dir)
     wiki.delete_page(page, "test commit")
   end
-
-  def get_slugs(page_or_dir)
-    if page_or_dir.is_a? WikiPage
-      [page_or_dir.slug]
-    else
-      page_or_dir.pages.present? ? page_or_dir.pages.map(&:slug) : []
-    end
-  end
 end

spec/routing/project_routing_spec.rb

@@ -3,9 +3,12 @@ require 'spec_helper'
 describe 'project routing' do
   before do
     allow(Project).to receive(:find_by_full_path).and_return(false)
-    allow(Project).to receive(:find_by_full_path).with('gitlab/gitlabhq', any_args).and_return(true)
+    allow(Project).to receive(:find_by_full_path).with('gitlab/gitlabhq', any_args).and_return(project)
   end
 
+  set(:namespace) { create(:namespace, name: 'gitlab') }
+  set(:project) { create(:project, namespace: namespace, name: 'gitlabhq') }
+
   # Shared examples for a resource inside a Project
   #
   # By default it tests all the default REST actions: index, create, new, edit,
@@ -145,24 +148,39 @@ describe 'project routing' do
     it_behaves_like 'redirecting a legacy project path', "/gitlab/gitlabhq/autocomplete_sources/labels", "/gitlab/gitlabhq/-/autocomplete_sources/labels"
   end
 
-  #  pages_project_wikis GET    /:project_id/wikis/pages(.:format)       projects/wikis#pages
-  # history_project_wiki GET    /:project_id/wikis/:id/history(.:format) projects/wikis#history
-  #        project_wikis POST   /:project_id/wikis(.:format)             projects/wikis#create
-  #    edit_project_wiki GET    /:project_id/wikis/:id/edit(.:format)    projects/wikis#edit
-  #         project_wiki GET    /:project_id/wikis/:id(.:format)         projects/wikis#show
-  #                      DELETE /:project_id/wikis/:id(.:format)         projects/wikis#destroy
+  # GET    /:project_id/wikis/pages(.:format)             projects/wikis#pages
+  # GET    /:project_id/-/wiki_pages/:id/history(.:format) projects/wiki_pages#history
+  # POST   /:project_id/-/wiki_pages(.:format)             projects/wiki_pages#create
+  # GET    /:project_id/-/wiki_pages/:id/edit(.:format)    projects/wiki_pages#edit
+  # GET    /:project_id/-/wiki_pages/:id(.:format)         projects/wiki_pages#show
+  # DELETE /:project_id/-/wiki_pages/:id(.:format)         projects/wiki_pages#destroy
   describe Projects::WikisController, 'routing' do
-    it 'to #pages' do
-      expect(get('/gitlab/gitlabhq/wikis/pages')).to route_to('projects/wikis#pages', namespace_id: 'gitlab', project_id: 'gitlabhq')
+    let(:wiki) { ProjectWiki.new(project, project.owner) }
+    let(:wiki_page) { create(:wiki_page, wiki: wiki) }
+
+    it '#pages' do
+      expect(get('/gitlab/gitlabhq/wikis/pages'))
+        .to route_to('projects/wikis#pages',
+                     namespace_id: 'gitlab',
+                     project_id: 'gitlabhq')
     end
 
-    it 'to #history' do
-      expect(get('/gitlab/gitlabhq/wikis/1/history')).to route_to('projects/wikis#history', namespace_id: 'gitlab', project_id: 'gitlabhq', id: '1')
+    describe '#history' do
+      let(:history_path) { project_wiki_history_path(project, wiki_page) }
+
+      it 'routes to history' do
+        expect(get(history_path))
+          .to route_to('projects/wiki_pages#history',
+                       namespace_id: namespace.path,
+                       project_id: project.name,
+                       id: wiki_page.slug)
+      end
     end
 
     it_behaves_like 'RESTful project resources' do
       let(:actions)    { [:create, :edit, :show, :destroy] }
-      let(:controller) { 'wikis' }
+      let(:controller) { 'wiki_pages' }
+      let(:controller_path) { '-/wiki_pages' }
     end
   end
 

spec/routing/wiki_routing_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+# We build URIs to wiki pages manually in various places (most notably
+# in markdown generation). To ensure these do not get out of sync, these
+# tests verify that our path generation assumptions are sound.
+describe 'Wiki path generation assumptions' do
+  set(:project) { create(:project, :public, :repository) }
+
+  let(:project_wiki) { ProjectWiki.new(project, project.owner) }
+  let(:some_page_name) { 'some-wiki-page' }
+  let(:wiki_page) do
+    create(:wiki_page, wiki: project_wiki, attrs: { title: some_page_name })
+  end
+
+  describe 'WikiProject#wiki_page_path', 'routing' do
+    it 'is consistent with routing to wiki#show' do
+      uri = URI.parse(project_wiki.wiki_page_path)
+      path = ::File.join(uri.path, some_page_name)
+
+      expect(get('/' + path)).to route_to('projects/wiki_pages#show',
+                                          id: some_page_name,
+                                          namespace_id: project.namespace.to_param,
+                                          project_id: project.to_param)
+    end
+  end
+
+  describe 'project_wiki_path', 'routing' do
+    describe 'GET' do
+      it 'routes to the :show action' do
+        path = project_wiki_path(project, wiki_page)
+
+        expect(get('/' + path)).to route_to('projects/wiki_pages#show',
+                                            id: wiki_page.slug,
+                                            namespace_id: project.namespace.to_param,
+                                            project_id: project.to_param)
+      end
+    end
+  end
+
+  describe 'project_wiki_pages_new_path', 'routing' do
+    describe 'GET' do
+      it 'routes to the :new action' do
+        path = project_wiki_pages_new_path(project)
+
+        expect(get('/' + path)).to route_to('projects/wiki_pages#new',
+                                            namespace_id: project.namespace.to_param,
+                                            project_id: project.to_param)
+      end
+    end
+  end
+
+  # Early versions of the wiki paths routed all wiki pages at
+  # /wikis/:id - this test exists to guarantee that we support
+  # old URIs that may be out there, saved in bookmarks, on other wikis, etc.
+  describe 'legacy route support', type: 'request' do
+    let(:path) { ::File.join(project_wikis_path(project), some_page_name) }
+
+    before do
+      get(path)
+    end
+
+    it 'routes to new wiki paths' do
+      dest = project_wiki_path(project, wiki_page)
+
+      expect(response).to redirect_to(dest)
+    end
+
+    context 'the page is nested in a directory' do
+      let(:some_page_name) { 'some-dir/some-deep-dir/some-page' }
+      let(:path) { ::File.join(project_wikis_path(project), some_page_name) }
+
+      it 'still routes correctly' do
+        dest = project_wiki_path(project, wiki_page)
+
+        expect(response).to redirect_to(dest)
+      end
+    end
+
+    context 'the user requested the old history path' do
+      let(:some_page_name) { 'some-dir/some-deep-dir/some-page' }
+      let(:path) { ::File.join(project_wikis_path(project), some_page_name, 'history') }
+
+      it 'redirects to the new history path' do
+        dest = project_wiki_history_path(project, wiki_page)
+
+        expect(response).to redirect_to(dest)
+      end
+    end
+
+    context 'the user requested the old edit path' do
+      let(:some_page_name) { 'some-dir/some-deep-dir/some-page' }
+      let(:path) { ::File.join(project_wikis_path(project), some_page_name, 'edit') }
+
+      it 'redirects to the new history path' do
+        dest = project_wiki_edit_path(project, wiki_page)
+
+        expect(response).to redirect_to(dest)
+      end
+    end
+  end
+end

spec/support/controllers/authorization_helpers.rb

+# frozen_string_literal: true
+
+def forbid_controller_ability!(ability)
+  allow(controller).to receive(:can?).and_call_original
+  allow(controller).to receive(:can?).with(anything, ability, any_args).and_return(false)
+end

spec/support/helpers/capybara_helpers.rb

@@ -46,4 +46,14 @@ module CapybaraHelpers
   def javascript_test?
     Capybara.current_driver == Capybara.javascript_driver
   end
+
+  def scroll_to(element)
+    raise 'JS not available' unless javascript_test?
+
+    script = <<-JS
+      arguments[0].scrollIntoView(true);
+    JS
+
+    page.driver.browser.execute_script(script, element.native)
+  end
 end

spec/support/helpers/dropzone_helper.rb

@@ -14,6 +14,8 @@ module DropzoneHelper
   # If it's 'false', then the helper will NOT wait for backend response
   # It lets to test behaviors while AJAX is processing.
   def dropzone_file(files, max_file_size = 0, wait_for_queuecomplete = true)
+    # Assert that there is a dropzone to use (waiting until it is ready)
+    expect(page).to have_css('.div-dropzone')
     # Generate a fake file input that Capybara can attach to
     page.execute_script <<-JS.strip_heredoc
       $('#fakeFileInput').remove();

spec/support/helpers/git_helpers.rb

@@ -2,8 +2,11 @@
 
 module GitHelpers
   def rugged_repo(repository)
-    path = File.join(TestEnv.repos_path, repository.disk_path + '.git')
+    rugged_repo_at_path(repository.disk_path + '.git')
+  end
 
+  def rugged_repo_at_path(relative_path)
+    path = File.join(TestEnv.repos_path, relative_path)
     Rugged::Repository.new(path)
   end
 end

spec/support/helpers/wiki_helpers.rb

@@ -12,4 +12,10 @@ module WikiHelpers
     ::Wikis::CreateAttachmentService.new(project, user, opts)
                                     .execute[:result][:file_path]
   end
+
+  # Generate the form field name for a given attribute of an object.
+  # This is rather general, but is currently only used in the wiki featur tests.
+  def form_field_name(obj, attr_name)
+    "#{ActiveModel::Naming.param_key(obj)}[#{attr_name}]"
+  end
 end

spec/support/matchers/issuable_matchers.rb

@@ -2,7 +2,8 @@
 
 RSpec::Matchers.define :have_header_with_correct_id_and_link do |level, text, id, parent = ".md"|
   match do |actual|
-    node = find("#{parent} h#{level} a#user-content-#{id}")
+    # anchors may be invisible
+    node = find("#{parent} h#{level} a#user-content-#{id}", visible: false)
 
     expect(node[:href]).to end_with("##{id}")
 

spec/support/shared_examples/wiki_file_attachments_examples.rb

@@ -42,7 +42,7 @@ shared_examples 'wiki file attachments' do
       end
     end
 
-    context 'uploading is complete', :quarantine do
+    context 'uploading is complete' do
       it 'shows "Attach a file" button on uploading complete' do
         attach_with_dropzone
         wait_for_requests
@@ -52,11 +52,11 @@ shared_examples 'wiki file attachments' do
       end
 
       it 'the markdown link is added to the page' do
-        fill_in(:wiki_content, with: '')
+        fill_in(:wiki_page_content, with: '')
         attach_with_dropzone(true)
         wait_for_requests
 
-        expect(page.find('#wiki_content').value)
+        expect(page.find('#wiki_page_content').value)
           .to match(%r{\!\[dk\]\(uploads/\h{32}/dk\.png\)$})
       end
 
@@ -70,7 +70,7 @@ shared_examples 'wiki file attachments' do
         img_link = page.find('a.no-attachment-icon img')['src']
 
         expect(link).to eq img_link
-        expect(URI.parse(link).path).to eq File.join(wiki.wiki_base_path, file_path)
+        expect(URI.parse(link).path).to eq File.join(wiki.wiki_page_path, file_path)
       end
 
       it 'the file has been added to the wiki repository' do