WikiPage: Expose user, support identity equality

Exposes `@user` as `user`, so that the current page author can be
identified.

Change equality to match other DB objects: pages with equal slugs are
equal.

app/models/project_wiki.rb

@@ -19,10 +19,11 @@ class ProjectWiki
   DIRECTION_DESC = 'desc'
   DIRECTION_ASC = 'asc'
 
+  attr_reader :project, :user
+
   # Returns a string describing what went wrong after
   # an operation fails.
   attr_reader :error_message
-  attr_reader :project
 
   def initialize(project, user = nil)
     @project = project
@@ -196,9 +197,9 @@ class ProjectWiki
 
   def commit_details(action, message = nil, title = nil)
     commit_message = message.presence || default_message(action, title)
-    git_user = Gitlab::Git::User.from_gitlab(@user)
+    git_user = Gitlab::Git::User.from_gitlab(user)
 
-    Gitlab::Git::Wiki::CommitDetails.new(@user.id,
+    Gitlab::Git::Wiki::CommitDetails.new(user.id,
                                          git_user.username,
                                          git_user.name,
                                          git_user.email,
@@ -206,7 +207,7 @@ class ProjectWiki
   end
 
   def default_message(action, title)
-    "#{@user.username} #{action} page: #{title}"
+    "#{user.username} #{action} page: #{title}"
   end
 
   def update_project_activity

app/models/wiki_page.rb

@@ -21,6 +21,14 @@ class WikiPage
     ActiveModel::Name.new(self, nil, 'wiki')
   end
 
+  def eql?(other)
+    return false unless other.present? && other.is_a?(self.class)
+
+    slug == other.slug && wiki.project == other.wiki.project
+  end
+
+  alias_method :==, :eql?
+
   # Sorts and groups pages by directory.
   #
   # pages - an array of WikiPage objects.
@@ -58,6 +66,7 @@ class WikiPage
 
   # The GitLab ProjectWiki instance.
   attr_reader :wiki
+  delegate :project, to: :wiki
 
   # The raw Gitlab::Git::WikiPage instance.
   attr_reader :page
@@ -70,6 +79,10 @@ class WikiPage
     Gitlab::HookData::WikiPageBuilder.new(self).build
   end
 
+  # Construct a new WikiPage
+  #
+  # @param [ProjectWiki] wiki
+  # @param [Gitlab::Git::WikiPage] page
   def initialize(wiki, page = nil)
     @wiki       = wiki
     @page       = page

lib/gitlab/hook_data/wiki_page_builder.rb

@@ -12,6 +12,10 @@ module Gitlab
             'content' => absolute_image_urls(wiki_page.content)
           )
       end
+
+      def uploads_prefix
+        ''
+      end
     end
   end
 end

spec/models/wiki_page_spec.rb

@@ -606,12 +606,36 @@ describe WikiPage do
       expect(subject).to eq(subject)
     end
 
-    it 'returns false for updated wiki page' do
+    it 'returns true for updated wiki page' do
       subject.update(content: "Updated content")
-      updated_page = wiki.find_page('test page')
+      updated_page = wiki.find_page(existing_page.slug)
 
       expect(updated_page).not_to be_nil
-      expect(updated_page).not_to eq(subject)
+      expect(updated_page).to eq(subject)
+    end
+
+    it 'returns false for a completely different wiki page' do
+      other_page = create(:wiki_page)
+
+      expect(subject.slug).not_to eq(other_page.slug)
+      expect(subject.project).not_to eq(other_page.project)
+      expect(subject).not_to eq(other_page)
+    end
+
+    it 'returns false for page with different slug on same project' do
+      other_page = create(:wiki_page, project: subject.project)
+
+      expect(subject.slug).not_to eq(other_page.slug)
+      expect(subject.project).to eq(other_page.project)
+      expect(subject).not_to eq(other_page)
+    end
+
+    it 'returns false for page with the same slug on a different project' do
+      other_page = create(:wiki_page, title: existing_page.slug)
+
+      expect(subject.slug).to eq(other_page.slug)
+      expect(subject.project).not_to eq(other_page.project)
+      expect(subject).not_to eq(other_page)
     end
   end
 
@@ -640,6 +664,30 @@ describe WikiPage do
     end
   end
 
+  describe '#meta' do
+    it 'returns an appropriate metadata object' do
+      wiki_page = create(:wiki_page)
+
+      expect(wiki_page.meta).to have_attributes(
+        valid?: true,
+        canonical_slug: wiki_page.slug,
+        title: wiki_page.title,
+        project: wiki_page.project,
+        slugs: include(have_attributes(slug: wiki_page.slug))
+      )
+    end
+
+    it 'is up-to-date after updates' do
+      wiki_page = create(:wiki_page)
+      old_title = wiki_page.title
+      new_title = FFaker::Lorem.sentence
+
+      expect do
+        wiki_page.update(title: new_title)
+      end.to change { wiki_page.meta.title }.from(old_title).to(new_title)
+    end
+  end
+
   private
 
   def remove_temp_repo(path)