Refactored decoder responsibilities (#1402)

- improved comment handling
- yaml decoder now responsible for leading content work around

pkg/yqlib/operator_encoder_decoder.go

@@ -21,7 +21,7 @@ func configureEncoder(format PrinterOutputFormat, indent int) Encoder {
 	case TSVOutputFormat:
 		return NewCsvEncoder('\t')
 	case YamlOutputFormat:
-		return NewYamlEncoder(indent, false, true, true)
+		return NewYamlEncoder(indent, false, ConfiguredYamlPreferences)
 	case XMLOutputFormat:
 		return NewXMLEncoder(indent, ConfiguredXMLPreferences)
 	case Base64OutputFormat:
@@ -102,7 +102,7 @@ func decodeOperator(d *dataTreeNavigator, context Context, expressionNode *Expre
 	var decoder Decoder
 	switch preferences.format {
 	case YamlInputFormat:
-		decoder = NewYamlDecoder()
+		decoder = NewYamlDecoder(ConfiguredYamlPreferences)
 	case XMLInputFormat:
 		decoder = NewXMLDecoder(ConfiguredXMLPreferences)
 	case Base64InputFormat:
@@ -121,17 +121,19 @@ func decodeOperator(d *dataTreeNavigator, context Context, expressionNode *Expre
 
 		context.SetVariable("decoded: "+candidate.GetKey(), candidate.AsList())
 
-		var dataBucket yaml.Node
 		log.Debugf("got: [%v]", candidate.Node.Value)
 
-		decoder.Init(strings.NewReader(unwrapDoc(candidate.Node).Value))
+		err := decoder.Init(strings.NewReader(unwrapDoc(candidate.Node).Value))
+		if err != nil {
+			return Context{}, err
+		}
 
-		errorReading := decoder.Decode(&dataBucket)
+		decodedNode, errorReading := decoder.Decode()
 		if errorReading != nil {
 			return Context{}, errorReading
 		}
 		//first node is a doc
-		node := unwrapDoc(&dataBucket)
+		node := unwrapDoc(decodedNode.Node)
 
 		results.PushBack(candidate.CreateReplacement(node))
 	}