Add condition to not merge arrays with default (#24)

* Add condition to not merge arrays with default

* Update node_spec

* Use fallback instead of conditional logic

* Move default concern up to public get method

Author: adamrdavid

lib/vrt/mapping.rb

@@ -26,12 +26,11 @@ def get(id_list, version)
           acc[key.to_sym] = get_key(
             id_list: id_list,
             mapping: mapping,
-            key: key,
-            default: default&.try(:[], key)
-          )
+            key: key
+          ) || default&.try(:[], key)
         end
       else
-        get_key(id_list: id_list, mapping: mapping, key: @scheme, default: default)
+        get_key(id_list: id_list, mapping: mapping, key: @scheme) || default
       end
     end
 
@@ -65,10 +64,10 @@ def key_by_id(mapping)
       end
     end
 
-    def get_key(id_list:, mapping:, key:, default:)
+    def get_key(id_list:, mapping:, key:)
       # iterate through the id components, keeping track of where we are in the mapping file
       # and the most specific mapped value found so far
-      best_guess = default
+      best_guess = nil
       id_list.each do |id|
         entry = mapping[id]
         break unless entry # mapping file doesn't go this deep, return previous value

spec/vrt/mappings_spec.rb

@@ -127,6 +127,27 @@
           end
         end
       end
+
+      context 'with arrays as the mapping values' do
+        subject { described_class.new(:cwe).get(id_list, version) }
+        let(:version) { '999.999' }
+
+        context 'when mapping has a default' do
+          let(:id_list) { %i[server_security_misconfiguration] }
+
+          it 'does NOT include the default mapping value' do
+            is_expected.to contain_exactly('CWE-933')
+          end
+
+          context 'no mapping exists' do
+            let(:id_list) { %i[other] }
+
+            it 'only includes the default mapping value' do
+              is_expected.to contain_exactly('CWE-2000')
+            end
+          end
+        end
+      end
     end
   end
 end

spec/vrt/node_spec.rb

@@ -80,8 +80,7 @@
       it 'has the exepected (concatenated) CWE IDs' do
         expect(mappings[:cwe]).to eq [
           'CWE-942',
-          'CWE-933',
-          'CWE-2000'
+          'CWE-933'
         ]
       end
     end