Fix Project Wiki update

app/controllers/projects/wikis_controller.rb

@@ -45,8 +45,9 @@ class Projects::WikisController < Projects::ApplicationController
     return render('empty') unless can?(current_user, :create_wiki, @project)
 
     @page = @project_wiki.find_page(params[:id])
+    @page = WikiPages::UpdateService.new(@project, current_user, wiki_params).execute(@page)
 
-    if @page = WikiPages::UpdateService.new(@project, current_user, wiki_params).execute(@page)
+    if @page.valid?
       redirect_to(
         namespace_project_wiki_path(@project.namespace, @project, @page),
         notice: 'Wiki was successfully updated.'

app/helpers/nav_helper.rb

@@ -16,6 +16,7 @@ module NavHelper
       "page-gutter build-sidebar right-sidebar-expanded"
     elsif current_path?('wikis#show') ||
         current_path?('wikis#edit') ||
+        current_path?('wikis#update') ||
         current_path?('wikis#history') ||
         current_path?('wikis#git_access')
       "page-gutter wiki-sidebar right-sidebar-expanded"

app/models/wiki_page.rb

@@ -155,7 +155,7 @@ class WikiPage
   end
 
   # Returns boolean True or False if this instance
-  # has been fully saved to disk or not.
+  # has been fully created on disk or not.
   def persisted?
     @persisted == true
   end
@@ -226,6 +226,8 @@ class WikiPage
   end
 
   def save(method, *args)
+    saved = false
+
     project_wiki = wiki
     if valid? && project_wiki.send(method, *args)
 
@@ -243,10 +245,10 @@ class WikiPage
       set_attributes
 
       @persisted = true
+      saved = true
     else
       errors.add(:base, project_wiki.error_message) if project_wiki.error_message
-      @persisted = false
     end
-    @persisted
+    saved
   end
 end

changelogs/unreleased/29405-fix-project-wiki-update.yml

+---
+title: Fix Project Wiki update
+merge_request: 9990
+author: Dongqing Hu

spec/features/projects/wiki/user_updates_wiki_page_spec.rb

@@ -15,7 +15,8 @@ feature 'Projects > Wiki > User updates wiki page', feature: true do
   context 'in the user namespace' do
     let(:project) { create(:project, namespace: user.namespace) }
 
-    scenario 'the home page' do
+    context 'the home page' do
+      scenario 'success when the wiki content is not empty' do
         click_link 'Edit'
 
         fill_in :wiki_content, with: 'My awesome wiki!'
@@ -25,6 +26,20 @@ feature 'Projects > Wiki > User updates wiki page', feature: true do
         expect(page).to have_content("Last edited by #{user.name}")
         expect(page).to have_content('My awesome wiki!')
       end
+
+      scenario 'failure when the wiki content is empty' do
+        click_link 'Edit'
+
+        fill_in :wiki_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 ''
+      end
+    end
   end
 
   context 'in a group namespace' do