Add yapf for Config.pretty_text (#281)

* add yapf for pretty text

* add yapf style

mmcv/utils/config.py

@@ -8,6 +8,7 @@ from collections import abc
 from importlib import import_module
 
 from addict import Dict
+from yapf.yapflib.yapf_api import FormatCode
 
 from .path import check_file_exist
 
@@ -262,6 +263,12 @@ class Config(object):
 
         cfg_dict = self._cfg_dict.to_dict()
         text = _format_dict(cfg_dict, outest_level=True)
+        # copied from setup.cfg
+        yapf_style = dict(
+            based_on_style='pep8',
+            blank_line_before_nested_class_or_def=True,
+            split_before_expression_after_opening_paren=True)
+        text, _ = FormatCode(text, style_config=yapf_style, verify=True)
 
         return text
 

requirements.txt

 addict
 numpy
 pyyaml
+yapf

setup.cfg

@@ -17,6 +17,6 @@ line_length = 79
 multi_line_output = 0
 known_standard_library = pkg_resources,setuptools
 known_first_party = mmcv
-known_third_party = Cython,addict,cv2,numpy,pytest,resnet_cifar,torch,torchvision,yaml
+known_third_party = Cython,addict,cv2,numpy,pytest,resnet_cifar,torch,torchvision,yaml,yapf
 no_lines_before = STDLIB,LOCALFOLDER
 default_section = THIRDPARTY