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  • Committer: Canonical.com Patch Queue Manager
  • Date: 2010-10-15 11:29:38 UTC
  • mfrom: (5499.1.1 trunk)
  • Revision ID: pqm@pqm.ubuntu.com-20101015112938-8585tdgvnin38kfv
(vila) Add bzrlib/pyutils.py,
        and replace uses of __import__ with calls to pyutils.get_named_object
        (Andrew Bennetts)

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bzrlib/hooks.py
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"""Support for plugin hooking logic."""
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from bzrlib import registry
 
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from bzrlib import (
 
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    pyutils,
 
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    registry,
 
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    symbol_versioning,
 
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    )
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from bzrlib.lazy_import import lazy_import
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lazy_import(globals(), """
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import textwrap
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""")
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known_hooks = registry.Registry()
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# known_hooks registry contains
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# tuple of (module, member name) which is the hook point
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# module where the specific hooks are defined
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# callable to get the empty specific Hooks for that attribute
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known_hooks.register_lazy(('bzrlib.branch', 'Branch.hooks'), 'bzrlib.branch',
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    'BranchHooks')
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known_hooks.register_lazy(('bzrlib.bzrdir', 'BzrDir.hooks'), 'bzrlib.bzrdir',
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    'BzrDirHooks')
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known_hooks.register_lazy(('bzrlib.commands', 'Command.hooks'),
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    'bzrlib.commands', 'CommandHooks')
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known_hooks.register_lazy(('bzrlib.info', 'hooks'),
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    'bzrlib.info', 'InfoHooks')
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known_hooks.register_lazy(('bzrlib.lock', 'Lock.hooks'), 'bzrlib.lock',
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    'LockHooks')
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known_hooks.register_lazy(('bzrlib.merge', 'Merger.hooks'), 'bzrlib.merge',
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    'MergeHooks')
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known_hooks.register_lazy(('bzrlib.msgeditor', 'hooks'), 'bzrlib.msgeditor',
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    'MessageEditorHooks')
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known_hooks.register_lazy(('bzrlib.mutabletree', 'MutableTree.hooks'),
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    'bzrlib.mutabletree', 'MutableTreeHooks')
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known_hooks.register_lazy(('bzrlib.smart.client', '_SmartClient.hooks'),
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    'bzrlib.smart.client', 'SmartClientHooks')
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known_hooks.register_lazy(('bzrlib.smart.server', 'SmartTCPServer.hooks'),
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    'bzrlib.smart.server', 'SmartServerHooks')
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known_hooks.register_lazy(('bzrlib.status', 'hooks'),
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    'bzrlib.status', 'StatusHooks')
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known_hooks.register_lazy(
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    ('bzrlib.version_info_formats.format_rio', 'RioVersionInfoBuilder.hooks'),
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    'bzrlib.version_info_formats.format_rio', 'RioVersionInfoBuilderHooks')
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known_hooks.register_lazy(
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    ('bzrlib.merge_directive', 'BaseMergeDirective.hooks'),
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    'bzrlib.merge_directive', 'MergeDirectiveHooks')
 
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class KnownHooksRegistry(registry.Registry):
 
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    # known_hooks registry contains
 
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    # tuple of (module, member name) which is the hook point
 
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    # module where the specific hooks are defined
 
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    # callable to get the empty specific Hooks for that attribute
 
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    def register_lazy_hook(self, hook_module_name, hook_member_name,
 
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            hook_factory_member_name):
 
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        self.register_lazy((hook_module_name, hook_member_name),
 
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            hook_module_name, hook_factory_member_name)
 
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    def iter_parent_objects(self):
 
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        """Yield (hook_key, (parent_object, attr)) tuples for every registered
 
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        hook, where 'parent_object' is the object that holds the hook
 
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        instance.
 
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        This is useful for resetting/restoring all the hooks to a known state,
 
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        as is done in bzrlib.tests.TestCase._clear_hooks.
 
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        """
 
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        for key in self.keys():
 
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            yield key, self.key_to_parent_and_attribute(key)
 
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    def key_to_parent_and_attribute(self, (module_name, member_name)):
 
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        """Convert a known_hooks key to a (parent_obj, attr) pair.
 
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        :param key: A tuple (module_name, member_name) as found in the keys of
 
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            the known_hooks registry.
 
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        :return: The parent_object of the hook and the name of the attribute on
 
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            that parent object where the hook is kept.
 
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        """
 
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        parent_mod, parent_member, attr = pyutils.calc_parent_name(module_name,
 
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            member_name)
 
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        return pyutils.get_named_object(parent_mod, parent_member), attr
 
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_builtin_known_hooks = (
 
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    ('bzrlib.branch', 'Branch.hooks', 'BranchHooks'),
 
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    ('bzrlib.bzrdir', 'BzrDir.hooks', 'BzrDirHooks'),
 
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    ('bzrlib.commands', 'Command.hooks', 'CommandHooks'),
 
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    ('bzrlib.info', 'hooks', 'InfoHooks'),
 
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    ('bzrlib.lock', 'Lock.hooks', 'LockHooks'),
 
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    ('bzrlib.merge', 'Merger.hooks', 'MergeHooks'),
 
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    ('bzrlib.msgeditor', 'hooks', 'MessageEditorHooks'),
 
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    ('bzrlib.mutabletree', 'MutableTree.hooks', 'MutableTreeHooks'),
 
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    ('bzrlib.smart.client', '_SmartClient.hooks', 'SmartClientHooks'),
 
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    ('bzrlib.smart.server', 'SmartTCPServer.hooks', 'SmartServerHooks'),
 
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    ('bzrlib.status', 'hooks', 'StatusHooks'),
 
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    ('bzrlib.version_info_formats.format_rio', 'RioVersionInfoBuilder.hooks',
 
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        'RioVersionInfoBuilderHooks'),
 
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    ('bzrlib.merge_directive', 'BaseMergeDirective.hooks',
 
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        'MergeDirectiveHooks'),
 
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    )
 
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known_hooks = KnownHooksRegistry()
 
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for (_hook_module, _hook_attribute, _hook_class) in _builtin_known_hooks:
 
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    known_hooks.register_lazy_hook(_hook_module, _hook_attribute, _hook_class)
 
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del _builtin_known_hooks, _hook_module, _hook_attribute, _hook_class
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def known_hooks_key_to_object((module_name, member_name)):
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        the known_hooks registry.
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    :return: The object this specifies.
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    """
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    return registry._LazyObjectGetter(module_name, member_name).get_obj()
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def known_hooks_key_to_parent_and_attribute((module_name, member_name)):
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    """Convert a known_hooks key to a object.
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    :param key: A tuple (module_name, member_name) as found in the keys of
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        the known_hooks registry.
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    :return: The object this specifies.
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    """
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    member_list = member_name.rsplit('.', 1)
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    if len(member_list) == 2:
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        parent_name, attribute = member_list
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    else:
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        parent_name = None
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        attribute = member_name
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    parent = known_hooks_key_to_object((module_name, parent_name))
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    return parent, attribute
 
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    return pyutils.get_named_object(module_name, member_name)
 
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@symbol_versioning.deprecated_function(symbol_versioning.deprecated_in((2, 3)))
 
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def known_hooks_key_to_parent_and_attribute(key):
 
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    """See KnownHooksRegistry.key_to_parent_and_attribute."""
 
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    return known_hooks.key_to_parent_and_attribute(key)
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class Hooks(dict):