config: lazy KeywordsManager instantiation

This allows a config instance to be instantiated by portageq, while
accessing /etc/portage/package.keywords only on demand, solving
bug #418475 by avoiding PermissionDenied exceptions when possible.

diff --git a/pym/portage/package/ebuild/config.py b/pym/portage/package/ebuild/config.py
index 97cbd99605c766dff5001231d5fc06acd6c8a3c1..6f5680bdcc79de0d1638417a3c23f8f6b4f2403e 100644 (file)
--- a/pym/portage/package/ebuild/config.py
+++ b/pym/portage/package/ebuild/config.py
@@ -227,9 +227,12 @@ class config(object):
                        self._setcpv_args_hash = clone._setcpv_args_hash
 
                        # immutable attributes (internal policy ensures lack of mutation)
-                       self._keywords_manager = clone._keywords_manager
+                       self._locations_manager = clone._locations_manager
                        self._use_manager = clone._use_manager
                        self._mask_manager = clone._mask_manager
+                       # force instantiation of lazy immutable objects when cloning, so
+                       # that they're not instantiated more than once
+                       self._keywords_manager_obj = clone._keywords_manager
 
                        # shared mutable attributes
                        self._unknown_features = clone._unknown_features
@@ -274,9 +277,13 @@ class config(object):
                        self._expand_map = copy.deepcopy(clone._expand_map)
 
                else:
+                       # lazily instantiated objects
+                       self._keywords_manager_obj = None
+
                        locations_manager = LocationsManager(config_root=config_root,
                                config_profile_path=config_profile_path, eprefix=eprefix,
                                local_config=local_config, target_root=target_root)
+                       self._locations_manager = locations_manager
 
                        eprefix = locations_manager.eprefix
                        config_root = locations_manager.config_root
@@ -574,10 +581,6 @@ class config(object):
                                                d.pop(k, None)
                                self._repo_make_defaults[repo.name] = d
 
-                       #Read package.keywords and package.accept_keywords.
-                       self._keywords_manager = KeywordsManager(profiles_complex, abs_user_config, \
-                               local_config, global_accept_keywords=self.configdict["defaults"].get("ACCEPT_KEYWORDS", ""))
-
                        #Read all USE related files from profiles and optionally from user config.
                        self._use_manager = UseManager(self.repositories, profiles_complex, abs_user_config, user_config=local_config)
                        #Initialize all USE related variables we track ourselves.
@@ -881,6 +884,16 @@ class config(object):
                                writemsg("!!! %s\n" % str(e),
                                        noiselevel=-1)
 
+       @property
+       def _keywords_manager(self):
+               if self._keywords_manager_obj is None:
+                       self._keywords_manager_obj = KeywordsManager(
+                               self._locations_manager.profiles_complex,
+                               self._locations_manager.abs_user_config,
+                               self.local_config,
+                               global_accept_keywords=self.configdict["defaults"].get("ACCEPT_KEYWORDS", ""))
+               return self._keywords_manager_obj
+
        @property
        def pkeywordsdict(self):
                result = self._keywords_manager.pkeywordsdict.copy()