Implement lazy loading of color.map when either the codes or _styles

attribute is accessed. This provides and _init(config_root='/') function
that the prefix branch can use to substitute an appropriate config_root
value at runtime.

svn path=/main/trunk/; revision=14083

diff --git a/pym/portage/output.py b/pym/portage/output.py
index fbf6c01e4beab2d0132199fd3741c41dc47be7d4..373b9686fdd25d1c9e371be26f0c5cc5f84bd91d 100644 (file)
--- a/pym/portage/output.py
+++ b/pym/portage/output.py
@@ -141,7 +141,7 @@ _styles["PKG_NOMERGE_WORLD"]       = ( "blue", )
 _styles["PROMPT_CHOICE_DEFAULT"]   = ( "green", )
 _styles["PROMPT_CHOICE_OTHER"]     = ( "red", )
 
-def _parse_color_map(onerror=None):
+def _parse_color_map(config_root='/', onerror=None):
        """
        Parse /etc/portage/color.map and return a dict of error codes.
 
@@ -157,7 +157,7 @@ def _parse_color_map(onerror=None):
        # that can be called in order adjust the location that color.map
        # is read from.
        global codes, _styles
-       myfile = os.path.join('/', COLOR_MAP_FILE)
+       myfile = os.path.join(config_root, COLOR_MAP_FILE)
        ansi_code_pattern = re.compile("^[0-9;]*m$") 
        quotes = '\'"'
        def strip_quotes(token):
@@ -723,13 +723,46 @@ class TermProgressBar(ProgressBar):
                                ">" + ((max_bar_width - bar_width) * " ") + "]"
                        return image
 
-try:
-       _parse_color_map(onerror=lambda e: writemsg("%s\n" % str(e), noiselevel=-1))
-except FileNotFound:
-       pass
-except PermissionDenied, e:
-       writemsg(_("Permission denied: '%s'\n") % str(e), noiselevel=-1)
-       del e
-except PortageException, e:
-       writemsg("%s\n" % str(e), noiselevel=-1)
-       del e
+_color_map_loaded = False
+
+def _init(config_root='/'):
+       """
+       Load color.map from the given config_root. This is called automatically
+       on first access of the codes or _styles attributes (unless it has already
+       been called for some other reason).
+       """
+
+       global _color_map_loaded, codes, _styles
+       if _color_map_loaded:
+               return
+
+       _color_map_loaded = True
+       codes = object.__getattribute__(codes, '_attr')
+       _styles = object.__getattribute__(_styles, '_attr')
+
+       try:
+               _parse_color_map(config_root=config_root,
+                       onerror=lambda e: writemsg("%s\n" % str(e), noiselevel=-1))
+       except FileNotFound:
+               pass
+       except PermissionDenied, e:
+               writemsg(_("Permission denied: '%s'\n") % str(e), noiselevel=-1)
+               del e
+       except PortageException, e:
+               writemsg("%s\n" % str(e), noiselevel=-1)
+               del e
+
+class _LazyInitColorMap(portage.proxy.objectproxy.ObjectProxy):
+
+       __slots__ = ('_attr',)
+
+       def __init__(self, attr):
+               portage.proxy.objectproxy.ObjectProxy.__init__(self)
+               object.__setattr__(self, '_attr', attr)
+
+       def _get_target(self):
+               _init()
+               return object.__getattribute__(self, '_attr')
+
+codes = _LazyInitColorMap(codes)
+_styles = _LazyInitColorMap(_styles)