Coverage for /pythoncovmergedfiles/medio/medio/usr/local/lib/python3.8/site-packages/tensorflow/python/util/lazy_loader.py: 83%

1# Copyright 2015 The TensorFlow Authors. All Rights Reserved. 

2# 

3# Licensed under the Apache License, Version 2.0 (the "License"); 

4# you may not use this file except in compliance with the License. 

5# You may obtain a copy of the License at 

6# 

7# http://www.apache.org/licenses/LICENSE-2.0 

8# 

9# Unless required by applicable law or agreed to in writing, software 

10# distributed under the License is distributed on an "AS IS" BASIS, 

11# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 

12# See the License for the specific language governing permissions and 

13# limitations under the License. 

14# ============================================================================== 

15 

16"""A LazyLoader class.""" 

17 

18import importlib 

19import types 

20from tensorflow.python.platform import tf_logging as logging 

21 

22 

23class LazyLoader(types.ModuleType): 

24 """Lazily import a module, mainly to avoid pulling in large dependencies. 

25 

26 `contrib`, and `ffmpeg` are examples of modules that are large and not always 

27 needed, and this allows them to only be loaded when they are used. 

28 """ 

29 

30 # The lint error here is incorrect. 

31 def __init__(self, local_name, parent_module_globals, name, warning=None): 

32 self._local_name = local_name 

33 self._parent_module_globals = parent_module_globals 

34 self._warning = warning 

35 

36 super(LazyLoader, self).__init__(name) 

37 

38 def _load(self): 

39 """Load the module and insert it into the parent's globals.""" 

40 # Import the target module and insert it into the parent's namespace 

41 module = importlib.import_module(self.__name__) 

42 self._parent_module_globals[self._local_name] = module 

43 

44 # Emit a warning if one was specified 

45 if self._warning: 

46 logging.warning(self._warning) 

47 # Make sure to only warn once. 

48 self._warning = None 

49 

50 # Update this object's dict so that if someone keeps a reference to the 

51 # LazyLoader, lookups are efficient (__getattr__ is only called on lookups 

52 # that fail). 

53 self.__dict__.update(module.__dict__) 

54 

55 return module 

56 

57 def __getattr__(self, item): 

58 module = self._load() 

59 return getattr(module, item) 

60 

61 def __dir__(self): 

62 module = self._load() 

63 return dir(module)