Add latest changes from gitlab-org/gitlab@master

41 files changed, 798 insertions, 351 deletions

diff --git a/app/assets/javascripts/pages/projects/wiki_directories/index.js b/app/assets/javascripts/pages/projects/wiki_directories/index.js
new file mode 100644
index 00000000000..b055b7cc322
--- /dev/null
+++ b/app/assets/javascripts/pages/projects/wiki_directories/index.js
@@ -0,0 +1,2 @@
+// currently, this controller inherits all behaviors from wikis
+import '../wikis/index';
diff --git a/app/assets/javascripts/pages/projects/wiki_pages/index.js b/app/assets/javascripts/pages/projects/wiki_pages/index.js
new file mode 100644
index 00000000000..92549cb648c
--- /dev/null
+++ b/app/assets/javascripts/pages/projects/wiki_pages/index.js
@@ -0,0 +1,43 @@
+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,
+          },
+        });
+      },
+    });
+  }
+});
diff --git a/app/assets/javascripts/pages/projects/wikis/index.js b/app/assets/javascripts/pages/projects/wikis/index.js
index f5fd84d69ac..1b0d8fb4b71 100644
--- a/app/assets/javascripts/pages/projects/wikis/index.js
+++ b/app/assets/javascripts/pages/projects/wikis/index.js
@@ -1,41 +1,11 @@
 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,
-          },
-        });
-      },
-    });
-  }
 });
diff --git a/app/assets/javascripts/pages/projects/wikis/wikis.js b/app/assets/javascripts/pages/projects/wikis/wikis.js
index d41199f6374..1bf799a5ee0 100644
--- a/app/assets/javascripts/pages/projects/wikis/wikis.js
+++ b/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}');
diff --git a/app/assets/stylesheets/framework/icons.scss b/app/assets/stylesheets/framework/icons.scss
index a53f5d85949..f73d1b41f84 100644
--- a/app/assets/stylesheets/framework/icons.scss
+++ b/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;
+  }
+}
diff --git a/app/assets/stylesheets/pages/wiki.scss b/app/assets/stylesheets/pages/wiki.scss
index 0b65b915abf..8f1b4cdb6d5 100644
--- a/app/assets/stylesheets/pages/wiki.scss
+++ b/app/assets/stylesheets/pages/wiki.scss
@@ -1,3 +1,31 @@
+.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;
diff --git a/app/controllers/concerns/preview_markdown.rb b/app/controllers/concerns/preview_markdown.rb
index 2a9729b6ffd..a3938ea3652 100644
--- a/app/controllers/concerns/preview_markdown.rb
+++ b/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
diff --git a/app/controllers/concerns/project_wiki_actions.rb b/app/controllers/concerns/project_wiki_actions.rb
new file mode 100644
index 00000000000..304e16a894a
--- /dev/null
+++ b/app/controllers/concerns/project_wiki_actions.rb
@@ -0,0 +1,41 @@
+# 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
diff --git a/app/controllers/projects/wiki_directories_controller.rb b/app/controllers/projects/wiki_directories_controller.rb
new file mode 100644
index 00000000000..f66da60f498
--- /dev/null
+++ b/app/controllers/projects/wiki_directories_controller.rb
@@ -0,0 +1,31 @@
+# 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
diff --git a/app/controllers/projects/wiki_pages_controller.rb b/app/controllers/projects/wiki_pages_controller.rb
new file mode 100644
index 00000000000..0ba397b08f8
--- /dev/null
+++ b/app/controllers/projects/wiki_pages_controller.rb
@@ -0,0 +1,180 @@
+# 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
diff --git a/app/controllers/projects/wikis_controller.rb b/app/controllers/projects/wikis_controller.rb
index b187fdb2723..d531d256721 100644
--- a/app/controllers/projects/wikis_controller.rb
+++ b/app/controllers/projects/wikis_controller.rb
@@ -1,120 +1,28 @@
 # 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'
-    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
-  end
-
-  def destroy
-    WikiPages::DestroyService.new(@project, current_user).execute(@page)
+    @wiki_entries = case @nesting
+                    when ProjectWiki::NESTING_FLAT
+                      @wiki_pages
+                    else
+                      WikiDirectory.group_by_directory(@wiki_pages)
+                    end
 
-    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')
+  def sort_params
+    process_params(sort_params_config)
   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)
-  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 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
+  def show_children_param
+    config = nesting_params_config(params[:sort])
 
-      @project_wiki.repository.blob_at(commit.id, params[:id])
-    end
+    process_params(config)
   end
 end
diff --git a/app/helpers/icons_helper.rb b/app/helpers/icons_helper.rb
index 4f73270577f..66b88f6b626 100644
--- a/app/helpers/icons_helper.rb
+++ b/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)
diff --git a/app/helpers/wiki_helper.rb b/app/helpers/wiki_helper.rb
index dd8fde2a697..3cf610cbd38 100644
--- a/app/helpers/wiki_helper.rb
+++ b/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
diff --git a/app/models/project_wiki.rb b/app/models/project_wiki.rb
index bb222ac7629..e0fcebf2642 100644
--- a/app/models/project_wiki.rb
+++ b/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)
 
diff --git a/app/models/wiki_directory.rb b/app/models/wiki_directory.rb
index 712ba79bbd2..6c86c11e7fb 100644
--- a/app/models/wiki_directory.rb
+++ b/app/models/wiki_directory.rb
@@ -1,20 +1,75 @@
 # 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
diff --git a/app/models/wiki_page.rb b/app/models/wiki_page.rb
index 1fa29e5b933..6b3cb0b39d8 100644
--- a/app/models/wiki_page.rb
+++ b/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
diff --git a/app/views/layouts/nav/sidebar/_project.html.haml b/app/views/layouts/nav/sidebar/_project.html.haml
index c84bc0b5cd4..ec27f3c24df 100644
--- a/app/views/layouts/nav/sidebar/_project.html.haml
+++ b/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')
diff --git a/app/views/projects/wiki_directories/_pages_wiki_directory.html.haml b/app/views/projects/wiki_directories/_pages_wiki_directory.html.haml
new file mode 100644
index 00000000000..a9d2f38da88
--- /dev/null
+++ b/app/views/projects/wiki_directories/_pages_wiki_directory.html.haml
@@ -0,0 +1,15 @@
+%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
diff --git a/app/views/projects/wiki_directories/_sidebar_wiki_directory.html.haml b/app/views/projects/wiki_directories/_sidebar_wiki_directory.html.haml
new file mode 100644
index 00000000000..2f62e9d4516
--- /dev/null
+++ b/app/views/projects/wiki_directories/_sidebar_wiki_directory.html.haml
@@ -0,0 +1,7 @@
+%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
+
diff --git a/app/views/projects/wiki_directories/_wiki_directory.html.haml b/app/views/projects/wiki_directories/_wiki_directory.html.haml
new file mode 100644
index 00000000000..022c209c5bd
--- /dev/null
+++ b/app/views/projects/wiki_directories/_wiki_directory.html.haml
@@ -0,0 +1 @@
+= render wiki_directory.to_partial_path(context), wiki_dir: wiki_directory, context: context
diff --git a/app/views/projects/wiki_directories/empty.html.haml b/app/views/projects/wiki_directories/empty.html.haml
new file mode 100644
index 00000000000..cab1c3acb60
--- /dev/null
+++ b/app/views/projects/wiki_directories/empty.html.haml
@@ -0,0 +1,34 @@
+- 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.')
diff --git a/app/views/projects/wiki_directories/show.html.haml b/app/views/projects/wiki_directories/show.html.haml
new file mode 100644
index 00000000000..4c7978d1216
--- /dev/null
+++ b/app/views/projects/wiki_directories/show.html.haml
@@ -0,0 +1,6 @@
+- 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) } }
diff --git a/app/views/projects/wikis/_form.html.haml b/app/views/projects/wiki_pages/_form.html.haml
index a153f527ee0..8f5757d6d98 100644
--- a/app/views/projects/wikis/_form.html.haml
+++ b/app/views/projects/wiki_pages/_form.html.haml
@@ -1,9 +1,11 @@
 - 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,
-           html: { class: form_classes },
-           data: { uploads_path: uploads_path } do |f|
+= 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)
 
   - if @page.persisted?
@@ -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?
diff --git a/app/views/projects/wiki_pages/_page_title.html.haml b/app/views/projects/wiki_pages/_page_title.html.haml
new file mode 100644
index 00000000000..a3b077999e6
--- /dev/null
+++ b/app/views/projects/wiki_pages/_page_title.html.haml
@@ -0,0 +1,4 @@
+= link_to @page.human_title, project_wiki_path(@project, @page)
+%span.light
+  = _('&middot;').html_safe
+  = subtitle
diff --git a/app/views/projects/wiki_pages/_pages_wiki_page.html.haml b/app/views/projects/wiki_pages/_pages_wiki_page.html.haml
new file mode 100644
index 00000000000..c177d03bee1
--- /dev/null
+++ b/app/views/projects/wiki_pages/_pages_wiki_page.html.haml
@@ -0,0 +1,8 @@
+%li
+  %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
diff --git a/app/views/projects/wiki_pages/_sidebar_wiki_page.html.haml b/app/views/projects/wiki_pages/_sidebar_wiki_page.html.haml
new file mode 100644
index 00000000000..205c3dd76bf
--- /dev/null
+++ b/app/views/projects/wiki_pages/_sidebar_wiki_page.html.haml
@@ -0,0 +1,11 @@
+- 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
diff --git a/app/views/projects/wiki_pages/_wiki_page.html.haml b/app/views/projects/wiki_pages/_wiki_page.html.haml
new file mode 100644
index 00000000000..947e96fed6b
--- /dev/null
+++ b/app/views/projects/wiki_pages/_wiki_page.html.haml
@@ -0,0 +1 @@
+= render wiki_page.to_partial_path(context), wiki_page: wiki_page
diff --git a/app/views/projects/wikis/edit.html.haml b/app/views/projects/wiki_pages/edit.html.haml
index 9ccf5acfefc..4e5f6a077a4 100644
--- a/app/views/projects/wikis/edit.html.haml
+++ b/app/views/projects/wiki_pages/edit.html.haml
@@ -1,5 +1,10 @@
-- @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
-          &middot;
-          = s_("Wiki|Edit Page")
+        = render partial: 'page_title', locals: { subtitle: s_("Wiki|Edit Page") }
       - else
         = s_("Wiki|Create New Page")
 
diff --git a/app/views/projects/wikis/history.html.haml b/app/views/projects/wiki_pages/history.html.haml
index d3a55c53649..d60a32750df 100644
--- a/app/views/projects/wikis/history.html.haml
+++ b/app/views/projects/wiki_pages/history.html.haml
@@ -1,3 +1,4 @@
+- @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
-        &middot;
-        = _("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'
diff --git a/app/views/projects/wikis/empty.html.haml b/app/views/projects/wiki_pages/missing_page.html.haml
index 62fa6e1907b..62fa6e1907b 100644
--- a/app/views/projects/wikis/empty.html.haml
+++ b/app/views/projects/wiki_pages/missing_page.html.haml
diff --git a/app/views/projects/wiki_pages/show.html.haml b/app/views/projects/wiki_pages/show.html.haml
new file mode 100644
index 00000000000..879ddfb03c8
--- /dev/null
+++ b/app/views/projects/wiki_pages/show.html.haml
@@ -0,0 +1,34 @@
+- @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'
diff --git a/app/views/projects/wikis/_pages_wiki_page.html.haml b/app/views/projects/wikis/_pages_wiki_page.html.haml
deleted file mode 100644
index c156f8cbf50..00000000000
--- a/app/views/projects/wikis/_pages_wiki_page.html.haml
+++ /dev/null
@@ -1,6 +0,0 @@
-%li
-  = link_to wiki_page.title, project_wiki_path(@project, wiki_page)
-  %small (#{wiki_page.format})
-  .float-right
-    - if wiki_page.last_version
-      %small= (s_("Last edited %{date}") % { date: time_ago_with_tooltip(wiki_page.last_version.authored_date) }).html_safe
diff --git a/app/views/projects/wikis/_sidebar_wiki_page.html.haml b/app/views/projects/wikis/_sidebar_wiki_page.html.haml
deleted file mode 100644
index 769d869bd53..00000000000
--- a/app/views/projects/wikis/_sidebar_wiki_page.html.haml
+++ /dev/null
@@ -1,3 +0,0 @@
-%li{ class: active_when(params[:id] == wiki_page.slug) }
-  = link_to project_wiki_path(@project, wiki_page) do
-    = wiki_page.human_title
diff --git a/app/views/projects/wikis/_wiki_directory.html.haml b/app/views/projects/wikis/_wiki_directory.html.haml
deleted file mode 100644
index 0e5f32ed859..00000000000
--- a/app/views/projects/wikis/_wiki_directory.html.haml
+++ /dev/null
@@ -1,4 +0,0 @@
-%li
-  = wiki_directory.slug
-  %ul
-    = render wiki_directory.pages, context: context
diff --git a/app/views/projects/wikis/_wiki_page.html.haml b/app/views/projects/wikis/_wiki_page.html.haml
deleted file mode 100644
index c84d06dad02..00000000000
--- a/app/views/projects/wikis/_wiki_page.html.haml
+++ /dev/null
@@ -1 +0,0 @@
-= render "#{context}_wiki_page", wiki_page: wiki_page
diff --git a/app/views/projects/wikis/pages.html.haml b/app/views/projects/wikis/pages.html.haml
deleted file mode 100644
index d9dcd8f9acd..00000000000
--- a/app/views/projects/wikis/pages.html.haml
+++ /dev/null
@@ -1,32 +0,0 @@
-- 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'
diff --git a/app/views/projects/wikis/show.html.haml b/app/views/projects/wikis/show.html.haml
index ebd99cf8605..9c732a933cf 100644
--- a/app/views/projects/wikis/show.html.haml
+++ b/app/views/projects/wikis/show.html.haml
@@ -1,32 +1,5 @@
-- @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) } }
diff --git a/app/views/shared/empty_states/_wikis.html.haml b/app/views/shared/empty_states/_wikis.html.haml
index 73eedcc1dc9..e05230de457 100644
--- a/app/views/shared/empty_states/_wikis.html.haml
+++ b/app/views/shared/empty_states/_wikis.html.haml
@@ -1,8 +1,11 @@
 - 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.')
diff --git a/app/views/projects/wikis/_main_links.html.haml b/app/views/shared/wiki/_main_links.html.haml
index 2e1e176c42a..5e41bb6a9cd 100644
--- a/app/views/projects/wikis/_main_links.html.haml
+++ b/app/views/shared/wiki/_main_links.html.haml
@@ -1,6 +1,6 @@
 - 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")
diff --git a/app/views/shared/wiki/_page_listing.html.haml b/app/views/shared/wiki/_page_listing.html.haml
new file mode 100644
index 00000000000..80f3071a8b2
--- /dev/null
+++ b/app/views/shared/wiki/_page_listing.html.haml
@@ -0,0 +1,45 @@
+- @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'
diff --git a/app/views/projects/wikis/_sidebar.html.haml b/app/views/shared/wiki/_sidebar.html.haml
index 83d145444d8..83d145444d8 100644
--- a/app/views/projects/wikis/_sidebar.html.haml
+++ b/app/views/shared/wiki/_sidebar.html.haml