Display multibuild flavors when asking for local project sources

There was a consistency gap between sources coming from local projects
and sources coming from remote projects. Multibuild flavors were only
shown for remote projects. Now the multibuild flavors are shown in both
cases.

Fixes #16911

src/api/app/controllers/source_project_controller.rb

@@ -22,6 +22,11 @@ def show
     @project = Project.find_by_name(project_name)
     raise Project::UnknownObjectError, "Project not found: #{project_name}" unless @project
 
+    if @project.scmsync.present?
+      pass_to_backend
+      return
+    end
+
     # we let the backend list the packages after we verified the project is visible
     if params.key?(:view)
       case params[:view]
@@ -52,7 +57,8 @@ def render_project_issues
   end
 
   def render_project_packages
-    @packages = params.key?(:expand) ? @project.expand_all_packages : @project.packages.pluck(:name)
+    # TODO: Display multibuild flavors when passing the expand param
+    @packages = params.key?(:expand) ? @project.expand_all_packages : @project.packages.sort_by(&:name)
     render locals: { expand: params.key?(:expand) }, formats: [:xml]
   end
 

src/api/app/views/source_project/show.xml.builder

@@ -1,9 +1,14 @@
 xml.directory(count: @packages.count) do
-  @packages.map do |name, project|
+  @packages.map do |package, project|
     if expand
-      xml.entry(name: name, originproject: project)
+      xml.entry(name: package, originproject: project)
+    elsif package.multibuild?
+      xml.entry(name: package.name)
+      package.multibuild_flavors.each do |flavor|
+        xml.entry(name: "#{package.name}:#{flavor}", originpackage: package.name)
+      end
     else
-      xml.entry(name: name)
+      xml.entry(name: package)
     end
   end
 end