move set_environ to its own function to allow customization in subcla…

…sses

environ/environ.py

@@ -950,19 +950,29 @@ def _keep_escaped_format_characters(match):
  else:
  logger.warning('Invalid line: %s', line)
 
- def set_environ(envval):
- """Return lambda to set environ.
-
- Use setdefault unless overwrite is specified.
- """
- if overwrite:
- return lambda k, v: envval.update({k: str(v)})
- return lambda k, v: envval.setdefault(k, str(v))
-
- setenv = set_environ(cls.ENVIRON)
-
  for key, value in overrides.items():
- setenv(key, value)
+ self.set_environ(envval=cls.ENVIRON, key=key, value=value, overwrite=overwrite)
+
+ @staticmethod
+ def set_environ(envval, key, value, overwrite):
+ """
+ set a the value for a key on envval
+ Use setdefault unless overwrite is specified.
+ :param envval:
+ dict of environment var data, such as an os.environ refrerence
+ :param str key:
+ enrionment var name
+ :param str value:
+ environment var value
+ :param bool overwrite:
+ default False
+ if true, overwrites existing environment variable values
+ if false, only sets evironment variable if not already set
+ :return: None
+ """
+ if overwrite:
+ return envval.update({k: str(v)}
+ return envval.setdefault(k, str(v)
 
 
 class FileAwareEnv(Env):