Make expand_variables_collection return Collection

lib/expand_variables.rb

@@ -19,7 +19,8 @@ module ExpandVariables
     # expand_variables_collection expands a Gitlab::Ci::Variables::Collection, ignoring unknown variable references.
     # If a circular variable reference is found, the original Collection is returned
     def expand_variables_collection(variables, project)
-      return variables if Feature.disabled?(:variable_inside_variable, project)
+      return Gitlab::Ci::Variables::Collection.new(variables) if
+        Feature.disabled?(:variable_inside_variable, project)
 
       sorted_variables = variables.sorted_collection(project)
       return sorted_variables if sorted_variables.errors
@@ -77,10 +78,11 @@ module ExpandVariables
     def expand_sorted_variables_collection(sorted_variables)
       expanded_vars = {}
 
-      sorted_variables.map do |item|
+      sorted_variables.each_with_object(Gitlab::Ci::Variables::Collection.new) do |item, collection|
         item = item.merge(value: expand_existing(item.value, expanded_vars)) if item.depends_on
 
         expanded_vars.store(item[:key], item)
+        collection.append(item)
       end
     end
   end

spec/lib/expand_variables_spec.rb

@@ -325,6 +325,10 @@ RSpec.describe ExpandVariables do
         with_them do
           subject { ExpandVariables.expand_variables_collection(variables, project_with_flag_disabled) }
 
+          it 'returns Collection' do
+            is_expected.to be_an_instance_of(Gitlab::Ci::Variables::Collection)
+          end
+
           it 'does not expand variables' do
             is_expected.to eq(variables)
           end
@@ -477,6 +481,10 @@ RSpec.describe ExpandVariables do
             ExpandVariables.expand_variables_collection(collection, project_with_flag_enabled)
           end
 
+          it 'returns Collection' do
+            is_expected.to be_an_instance_of(Gitlab::Ci::Variables::Collection)
+          end
+
           it 'expands variables' do
             is_expected.to eq(result)
           end