Show the status of a user in interactions

The status is shown for
- The author of a commit when viewing a commit
- Notes on a commit (regular/diff)
- The user that triggered a pipeline when viewing a pipeline
- The author of a merge request when viewing a merge request
- The author of notes on a merge request (regular/diff)
- The author of an issue when viewing an issue
- The author of notes on an issue
- The author of a snippet when viewing a snippet
- The author of notes on a snippet
- A user's profile page
- The list of members of a group/user

spec/support/matchers/user_status_matcher.rb

+# frozen_string_literal: true
+
+RSpec::Matchers.define :show_user_status do |status|
+  match do |page|
+    expect(page).to have_selector(".user-status-emoji[title='#{status.message}']")
+
+    # The same user status might be displayed multiple times on the page
+    emoji_span = page.first(".user-status-emoji[title='#{status.message}']")
+    page.within(emoji_span) do
+      expect(page).to have_emoji(status.emoji)
+    end
+  end
+end

spec/support/shared_examples/showing_user_status_shared_examples.rb

+# frozen_string_literal: true
+
+shared_examples 'showing user status' do
+  let!(:status) { create(:user_status, user: user_with_status, emoji: 'smirk', message: 'Authoring this object') }
+
+  it 'shows the status' do
+    subject
+
+    expect(page).to show_user_status(status)
+  end
+end

spec/views/projects/merge_requests/show.html.haml_spec.rb

@@ -17,6 +17,13 @@ describe 'projects/merge_requests/show.html.haml' do
       author: user)
   end
+  def preload_view_requirements
+    # This will load the status fields of the author of the note and merge request
+    # to avoid queries in when rendering the view being tested.
+    closed_merge_request.author.status
+    note.author.status
+  end
+
   before do
     assign(:project, project)
     assign(:merge_request, closed_merge_request)
@@ -26,6 +33,8 @@ describe 'projects/merge_requests/show.html.haml' do
     assign(:notes, [])
     assign(:pipelines, Ci::Pipeline.none)
+    preload_view_requirements
+
     allow(view).to receive_messages(current_user: user,
                                     can?: true,
                                     current_application_settings: Gitlab::CurrentSettings.current_application_settings)
@@ -42,6 +51,7 @@ describe 'projects/merge_requests/show.html.haml' do
     it 'does not show the "Reopen" button when the source project does not exist' do
       unlink_project.execute
       closed_merge_request.reload
+      preload_view_requirements
       render
@@ -56,6 +66,7 @@ describe 'projects/merge_requests/show.html.haml' do
       forked_project.destroy
       # Reload merge request so MergeRequest#source_project turns to `nil`
       closed_merge_request.reload
+      preload_view_requirements
       render