Added NDJSON decoder (#1281)

pkg/yqlib/lib.go

@@ -240,20 +240,28 @@ func guessTagFromCustomType(node *yaml.Node) string {
 		log.Warning("node has no value to guess the type with")
 		return node.Tag
 	}
+	dataBucket, errorReading := parseSnippet(node.Value)
 
-	decoder := NewYamlDecoder()
-	decoder.Init(strings.NewReader(node.Value))
-	var dataBucket yaml.Node
-	errorReading := decoder.Decode(&dataBucket)
 	if errorReading != nil {
 		log.Warning("could not guess underlying tag type %v", errorReading)
 		return node.Tag
 	}
-	guessedTag := unwrapDoc(&dataBucket).Tag
+	guessedTag := unwrapDoc(dataBucket).Tag
 	log.Info("im guessing the tag %v is a %v", node.Tag, guessedTag)
 	return guessedTag
 }
 
+func parseSnippet(value string) (*yaml.Node, error) {
+	decoder := NewYamlDecoder()
+	decoder.Init(strings.NewReader(value))
+	var dataBucket yaml.Node
+	err := decoder.Decode(&dataBucket)
+	if len(dataBucket.Content) == 0 {
+		return nil, fmt.Errorf("bad data")
+	}
+	return dataBucket.Content[0], err
+}
+
 func recursiveNodeEqual(lhs *yaml.Node, rhs *yaml.Node) bool {
 	if lhs.Kind != rhs.Kind {
 		return false