fix: YAMLLoadWarning by specify yaml loader

CHANGELOG.md

@@ -12,6 +12,7 @@
 
 - fix extend with testcase reference in format version 2
 - fix ImportError when locustio is not installed
+- fix YAMLLoadWarning by specify yaml loader
 
 ## 2.2.0 (2019-06-24)
 

httprunner/loader.py

@@ -35,7 +35,7 @@ def load_yaml_file(yaml_file):
     """ load yaml file and check file content format
     """
     with io.open(yaml_file, 'r', encoding='utf-8') as stream:
-        yaml_content = yaml.load(stream)
+        yaml_content = yaml.load(stream, Loader=yaml.FullLoader)
         _check_format(yaml_file, yaml_content)
         return yaml_content