Merge pull request #2513 from AriaXLi/fact-3135

(FACT-3135) Add support for yaml anchors in Facter 4

Author: mhashizume

lib/facter/custom_facts/util/parser.rb

@@ -119,9 +119,9 @@ def parse_results
           cont = content.gsub(TIME, '"\1"')
 
           if Gem::Version.new(Psych::VERSION) >= Gem::Version.new('3.1.0') # Ruby 2.6+
-            YAML.safe_load(cont, permitted_classes: [Date])
+            YAML.safe_load(cont, permitted_classes: [Date], aliases: true)
           else
-            YAML.safe_load(cont, [Date])
+            YAML.safe_load(cont, [Date], [], [], true)
           end
         end
       end

spec/custom_facts/util/parser_spec.rb

@@ -318,6 +318,16 @@ def expects_to_parse_powershell(cmd, result)
     let(:yaml_parser) { LegacyFacter::Util::Parser::YamlParser.new(nil, yaml_content) }
 
     describe '#parse_results' do
+      context 'when yaml anchors are present' do
+        let(:yaml_content) { load_fixture('external_fact_yaml_anchor').read }
+
+        it 'parses the yaml anchors' do
+          expected_result = { 'one' => { 'test' => { 'a' => ['foo'] } }, 'two' => { 'TEST' => { 'A' => ['foo'] } } }
+
+          expect(yaml_parser.parse_results).to eq(expected_result)
+        end
+      end
+
       context 'when yaml contains Time formatted fields' do
         context 'when time zone is present' do
           let(:yaml_content) { load_fixture('external_fact_yaml').read }

spec/fixtures/external_fact_yaml_anchor

@@ -0,0 +1,8 @@
+---
+one:
+  test:
+    a: &a1
+      - foo
+two:
+  TEST:
+    A: *a1