Support dot in config.py file (#207)

Signed-off-by: lizz <lizz@sensetime.com>

mmcv/utils/config.py

 # Copyright (c) Open-MMLab. All rights reserved.
 import os.path as osp
+import shutil
 import sys
+import tempfile
 from argparse import ArgumentParser
 from importlib import import_module
 
@@ -78,18 +80,17 @@ class Config(object):
         filename = osp.abspath(osp.expanduser(filename))
         check_file_exist(filename)
         if filename.endswith('.py'):
-            module_name = osp.basename(filename)[:-3]
-            if '.' in module_name:
-                raise ValueError('Dots are not allowed in config file path.')
-            config_dir = osp.dirname(filename)
-            sys.path.insert(0, config_dir)
-            mod = import_module(module_name)
-            sys.path.pop(0)
-            cfg_dict = {
-                name: value
-                for name, value in mod.__dict__.items()
-                if not name.startswith('__')
-            }
+            with tempfile.TemporaryDirectory() as temp_config_dir:
+                shutil.copyfile(filename,
+                                osp.join(temp_config_dir, '_tempconfig.py'))
+                sys.path.insert(0, temp_config_dir)
+                mod = import_module('_tempconfig')
+                sys.path.pop(0)
+                cfg_dict = {
+                    name: value
+                    for name, value in mod.__dict__.items()
+                    if not name.startswith('__')
+                }
         elif filename.endswith(('.yml', '.yaml', '.json')):
             import mmcv
             cfg_dict = mmcv.load(filename)

tests/data/config/a.b.py

+item1 = [1, 2]
+item2 = {'a': 0}
+item3 = True
+item4 = 'test'

tests/test_config.py

@@ -18,7 +18,7 @@ def test_construct():
 
 
 def test_fromfile():
-    for filename in ['a.py', 'b.json', 'c.yaml']:
+    for filename in ['a.py', 'a.b.py', 'b.json', 'c.yaml']:
         cfg_file = osp.join(osp.dirname(__file__), 'data/config', filename)
         cfg = Config.fromfile(cfg_file)
         assert isinstance(cfg, Config)
@@ -27,8 +27,6 @@ def test_fromfile():
 
     with pytest.raises(FileNotFoundError):
         Config.fromfile('no_such_file.py')
-    with pytest.raises(ValueError):
-        Config.fromfile(osp.join(osp.dirname(__file__), 'data/config/a.b.py'))
     with pytest.raises(IOError):
         Config.fromfile(osp.join(osp.dirname(__file__), 'data/color.jpg'))