Selectively hide public email on profile page

Toggle visibility through a feature flag. Intended as a workaround
before a more permanent solution is built.

app/helpers/users_helper.rb

@@ -172,6 +172,13 @@ module UsersHelper
     }
   end
 
+  def display_public_email?(user)
+    return false if user.public_email.blank?
+    return true unless user.provisioned_by_group
+
+    !Feature.enabled?(:hide_public_email_on_profile, user.provisioned_by_group)
+  end
+
   private
 
   def admin_users_paths

app/views/users/show.html.haml

@@ -112,7 +112,7 @@
                 - if Feature.enabled?(:security_auto_fix) && @user.bot?
                   = sprite_icon('question', css_class: 'gl-text-blue-600')
                 = link_to @user.short_website_url, @user.full_website_url, target: '_blank', rel: 'me noopener noreferrer nofollow', itemprop: 'url'
-            - unless @user.public_email.blank?
+            - if display_public_email?(@user)
               = render 'middle_dot_divider', stacking: true do
                 = link_to @user.public_email, "mailto:#{@user.public_email}", itemprop: 'email'
           .gl-text-gray-900

config/feature_flags/development/hide_public_email_on_profile.yml

+---
+name: hide_public_email_on_profile
+introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/79717
+rollout_issue_url: https://gitlab.com/gitlab-org/gitlab/-/issues/351731
+milestone: '14.8'
+type: development
+group: group::optimize
+default_enabled: false

ee/spec/features/profiles/user_visits_public_profile_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe 'User visits public profile' do
+  context 'when user profile is provisioned by group' do
+    let_it_be(:group) { create(:group) }
+    let_it_be(:scim_identity) { create(:scim_identity, group: group) }
+    let_it_be(:user) { create(:user, :public_email, provisioned_by_group_id: scim_identity.group.id) }
+
+    it 'hide public_email' do
+      visit(user_path(user))
+      expect(page).not_to have_content user.public_email
+    end
+
+    context 'when hide_public_email_on_profile feature flag is disabled' do
+      before do
+        stub_feature_flags(hide_public_email_on_profile: false)
+      end
+
+      it 'displays public_email' do
+        visit(user_path(user))
+        expect(page).to have_content user.public_email
+      end
+    end
+  end
+end

ee/spec/helpers/users_helper_spec.rb

@@ -104,4 +104,43 @@ RSpec.describe UsersHelper do
       end
     end
   end
+
+  describe '#display_public_email?' do
+    let_it_be(:group) { create(:group) }
+    let_it_be(:scim_identity) { create(:scim_identity, group: group) }
+
+    let(:user) { create(:user, :public_email, provisioned_by_group: scim_identity.group) }
+
+    subject { helper.display_public_email?(user) }
+
+    before do
+      stub_feature_flags hide_public_email_on_profile: false
+    end
+
+    it { is_expected.to be true }
+
+    context 'when public_email is blank' do
+      before do
+        user.update!(public_email: '')
+      end
+
+      it { is_expected.to be false }
+    end
+
+    context 'when provisioned_by_group is nil' do
+      before do
+        user.update!(provisioned_by_group: nil)
+      end
+
+      it { is_expected.to be true }
+    end
+
+    context 'when hide_public_email_on_profile is true' do
+      before do
+        stub_feature_flags hide_public_email_on_profile: true
+      end
+
+      it { is_expected.to be false }
+    end
+  end
 end