Add JSONObjectToYAMLObject

yaml.go

@@ -317,3 +317,47 @@ func convertToJSONableObject(yamlObj interface{}, jsonTarget *reflect.Value) (in
 		return yamlObj, nil
 	}
 }
+
+// JSONObjectToYAMLObject converts an in-memory JSON object into a YAML in-memory MapSlice,
+// without going through a byte representation.
+func JSONObjectToYAMLObject(j map[string]interface{}) yaml.MapSlice {
+	if j == nil {
+		return nil
+	}
+	ret := make(yaml.MapSlice, 0, len(j))
+	for k, v := range j {
+		ret = append(ret, yaml.MapItem{k, jsonToYAMLValue(v)})
+	}
+	return ret
+}
+
+func jsonToYAMLValue(j interface{}) interface{} {
+	switch j := j.(type) {
+	case map[string]interface{}:
+		return JSONObjectToYAMLObject(j)
+	case []interface{}:
+		ret := make([]interface{}, len(j))
+		for i := range j {
+			ret[i] = jsonToYAMLValue(j[i])
+		}
+		return ret
+	case float64:
+		// replicate the logic in https://github.com/go-yaml/yaml/blob/51d6538a90f86fe93ac480b35f37b2be17fef232/resolve.go#L151
+		if i64 := int64(j); j == float64(i64) {
+			if i := int(i64); i64 == int64(i) {
+				return i
+			}
+			return i64
+		}
+		if ui64 := uint64(j); j == float64(ui64) {
+			return ui64
+		}
+		return j
+	case int64:
+		if i := int(j); j == int64(i) {
+			return i
+		}
+		return j
+	}
+	return j
+}