Modify some email assets configurations to enable putting images outside assets

config/application.rb

@@ -385,7 +385,15 @@ module Gitlab
     initializer :correct_precompile_targets, after: :set_default_precompile do |app|
       app.config.assets.precompile.reject! { |entry| entry == Sprockets::Railtie::LOOSE_APP_ASSETS }
 
-      asset_roots = [config.root.join("app/assets").to_s]
+      # if two files in assets are named the same, it'll likely resolve to the normal app/assets version.
+      # See https://gitlab.com/gitlab-jh/gitlab/-/merge_requests/27#note_609101582 for more details
+      asset_roots = []
+
+      if Gitlab.jh?
+        asset_roots << config.root.join("jh/app/assets").to_s
+      end
+
+      asset_roots << config.root.join("app/assets").to_s
 
       if Gitlab.ee?
         asset_roots << config.root.join("ee/app/assets").to_s
@@ -413,16 +421,18 @@ module Gitlab
       end
     end
 
-    # Add EE assets. They should take precedence over CE. This means if two files exist, e.g.:
+    # Add assets for variants of GitLab. They should take precedence over CE.
+    # This means if multiple files exist, e.g.:
     #
+    # jh/app/assets/stylesheets/example.scss
     # ee/app/assets/stylesheets/example.scss
     # app/assets/stylesheets/example.scss
     #
-    # The ee/ version will be preferred.
-    initializer :prefer_ee_assets, after: :append_assets_path do |app|
-      if Gitlab.ee?
+    # The jh/ version will be preferred.
+    initializer :prefer_specialized_assets, after: :append_assets_path do |app|
+      Gitlab.extensions.each do |extension|
         %w[images javascripts stylesheets].each do |path|
-          app.config.assets.paths.unshift("#{config.root}/ee/app/assets/#{path}")
+          app.config.assets.paths.unshift("#{config.root}/#{extension}/app/assets/#{path}")
         end
       end
     end

spec/helpers/emails_helper_spec.rb

@@ -238,16 +238,16 @@ RSpec.describe EmailsHelper do
       it 'returns the default header logo' do
         create :appearance, header_logo: nil
 
-        expect(header_logo).to eq(
-          %{<img alt="GitLab" src="/images/mailers/gitlab_header_logo.gif" width="55" height="50" />}
+        expect(header_logo).to match(
+          %r{<img alt="GitLab" src="/images/mailers/gitlab_header_logo\.(?:gif|png)" width="\d+" height="\d+" />}
         )
       end
     end
 
     context 'there is no brand item' do
       it 'returns the default header logo' do
-        expect(header_logo).to eq(
-          %{<img alt="GitLab" src="/images/mailers/gitlab_header_logo.gif" width="55" height="50" />}
+        expect(header_logo).to match(
+          %r{<img alt="GitLab" src="/images/mailers/gitlab_header_logo\.(?:gif|png)" width="\d+" height="\d+" />}
         )
       end
     end