Add Wiki support for AsciiDoc include directive

GitLab added support for the AsciiDoc `include` directive in 3f5d7c7e.
The content of a file could be included if the file was part of the same
repository.

The Wiki `show` view was missing the expected variables needed for the
included file to be found in the repository. An AsciiDoc `include`
directive would instead cause a 500 error to be raised.

https://gitlab.com/gitlab-org/gitlab/issues/195625

app/controllers/projects/wikis_controller.rb

@@ -39,6 +39,10 @@ class Projects::WikisController < Projects::ApplicationController
     if @page
       set_encoding_error unless valid_encoding?
 
+      # Assign vars expected by MarkupHelper
+      @ref = params[:version_id]
+      @path = @page.path
+
       render 'show'
     elsif file_blob
       send_blob(@project_wiki.repository, file_blob)

app/helpers/markup_helper.rb

@@ -132,6 +132,7 @@ module MarkupHelper
       pipeline: :wiki,
       project: @project,
       project_wiki: @project_wiki,
+      repository: @project_wiki.repository,
       page_slug: wiki_page.slug,
       issuable_state_filter_enabled: true
     )

lib/gitlab/asciidoc/include_processor.rb

@@ -13,7 +13,7 @@ module Gitlab
         super(logger: Gitlab::AppLogger)
 
         @context = context
-        @repository = context[:project].try(:repository)
+        @repository = context[:repository] || context[:project].try(:repository)
 
         # Note: Asciidoctor calls #freeze on extensions, so we can't set new
         # instance variables after initialization.
@@ -111,7 +111,7 @@ module Gitlab
       end
 
       def ref
-        context[:ref] || context[:project].default_branch
+        context[:ref] || repository&.root_ref
       end
 
       def requested_path

spec/features/projects/wiki/users_views_asciidoc_page_with_includes_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe 'User views AsciiDoc page with includes', :js do
+  let_it_be(:user) { create(:user) }
+  let_it_be(:wiki_content_selector) { '[data-qa-selector=wiki_page_content]' }
+  let(:project) { create(:project, :public, :wiki_repo) }
+  let!(:included_wiki_page) { create_wiki_page('included_page', content: 'Content from the included page')}
+  let!(:wiki_page) { create_wiki_page('home', content: "Content from the main page.\ninclude::included_page.asciidoc[]") }
+
+  def create_wiki_page(title, content:)
+    attrs = {
+      title: title,
+      content: content,
+      format: :asciidoc
+    }
+
+    create(:wiki_page, wiki: project.wiki, attrs: attrs)
+  end
+
+  before do
+    sign_in(user)
+  end
+
+  context 'when the file being included exists' do
+    it 'includes the file contents' do
+      visit(project_wiki_path(project, wiki_page))
+
+      page.within(:css, wiki_content_selector) do
+        expect(page).to have_content('Content from the main page. Content from the included page')
+      end
+    end
+
+    context 'when there are multiple versions of the wiki pages' do
+      before do
+        included_wiki_page.update(message: 'updated included file', content: 'Updated content from the included page')
+        wiki_page.update(message: 'updated wiki page', content: "Updated content from the main page.\ninclude::included_page.asciidoc[]")
+      end
+
+      let(:latest_version_id) { wiki_page.versions.first.id }
+      let(:oldest_version_id) { wiki_page.versions.last.id }
+
+      context 'viewing the latest version' do
+        it 'includes the latest content' do
+          visit(project_wiki_path(project, wiki_page, version_id: latest_version_id))
+
+          page.within(:css, wiki_content_selector) do
+            expect(page).to have_content('Updated content from the main page. Updated content from the included page')
+          end
+        end
+      end
+
+      context 'viewing the original version' do
+        it 'includes the content from the original version' do
+          visit(project_wiki_path(project, wiki_page, version_id: oldest_version_id))
+
+          page.within(:css, wiki_content_selector) do
+            expect(page).to have_content('Content from the main page. Content from the included page')
+          end
+        end
+      end
+    end
+  end
+
+  context 'when the file being included does not exist' do
+    before do
+      included_wiki_page.delete
+    end
+
+    it 'outputs an error' do
+      visit(project_wiki_path(project, wiki_page))
+
+      page.within(:css, wiki_content_selector) do
+        expect(page).to have_content('Content from the main page. [ERROR: include::included_page.asciidoc[] - unresolved directive]')
+      end
+    end
+  end
+end

spec/helpers/markup_helper_spec.rb

@@ -273,16 +273,19 @@ describe MarkupHelper do
 
   describe '#render_wiki_content' do
     let(:wiki) { double('WikiPage', path: "file.#{extension}") }
+    let(:wiki_repository) { double('Repository') }
     let(:context) do
       {
         pipeline: :wiki, project: project, project_wiki: wiki,
-        page_slug: 'nested/page', issuable_state_filter_enabled: true
+        page_slug: 'nested/page', issuable_state_filter_enabled: true,
+        repository: wiki_repository
       }
     end
 
     before do
       expect(wiki).to receive(:content).and_return('wiki content')
       expect(wiki).to receive(:slug).and_return('nested/page')
+      expect(wiki).to receive(:repository).and_return(wiki_repository)
       helper.instance_variable_set(:@project_wiki, wiki)
     end
 

spec/lib/gitlab/asciidoc_spec.rb

@@ -518,6 +518,28 @@ module Gitlab
           end
         end
 
+        context 'when repository is passed into the context' do
+          let(:wiki_repo) { project.wiki.repository }
+          let(:include_path) { 'wiki_file.adoc' }
+
+          before do
+            project.create_wiki
+            context.merge!(repository: wiki_repo)
+          end
+
+          context 'when the file exists' do
+            before do
+              create_file(include_path, 'Content from wiki', repository: wiki_repo)
+            end
+
+            it { is_expected.to include('<p>Content from wiki</p>') }
+          end
+
+          context 'when the file does not exist' do
+            it { is_expected.to include("[ERROR: include::#{include_path}[] - unresolved directive]")}
+          end
+        end
+
         context 'recursive includes with relative paths' do
           let(:input) do
             <<~ADOC
@@ -562,8 +584,8 @@ module Gitlab
           end
         end
 
-        def create_file(path, content)
-          project.repository.create_file(project.creator, path, content,
+        def create_file(path, content, repository: project.repository)
+          repository.create_file(project.creator, path, content,
             message: "Add #{path}", branch_name: 'asciidoc')
         end
       end