mref with hash merging

Author: dhower-qc

lib/test/test_yaml_loader.rb

@@ -7,6 +7,37 @@
 
 class TestYamlLoader < Minitest::Test
 
+  def test_that_mref_with_nested_replace_works
+    yaml = <<~YAML
+      base:
+        key1:
+          sub_key1: value1
+        key2: value2
+
+      middle:
+        $mref: "#/base"
+        key3: value3
+        key4: value4
+
+      bottom:
+        $mref:
+        - "#/base"
+        - "#/middle"
+        key1:
+          sub_key6: value6
+        key2: value2_new
+        key4: value4_new
+        key5: value5
+    YAML
+
+    f = Tempfile.new("yml")
+    f.write(yaml)
+    f.flush
+
+    doc = YamlLoader.load(f.path)
+    assert_equal({ "key1" => {"sub_key1" => "value1", "sub_key6" => "value6"}, "key2" => "value2_new", "key3" => "value3", "key4" => "value4_new", "key5" => "value5" }, doc["bottom"])
+  end
+
   def test_that_spurious_recursive_mref_works
     yaml = <<~YAML
       base:

lib/yaml_loader.rb

@@ -83,7 +83,13 @@ def self.expand(filename, obj, yaml_opts = {})
       obj_keys.each do |key|
         value = obj[key]
 
-        new_obj[key] = expand(filename, value, yaml_opts)
+        expanded = expand(filename, value, yaml_opts)
+        if new_obj[key].is_a?(Hash)
+          raise "should be a hash" unless expanded.is_a?(Hash)
+          new_obj[key].merge!(expanded)
+        else
+          new_obj[key] = expanded
+        end
       end
       new_obj
     else