[Python-3000-checkins] r63966 - python/branches/py3k/Demo/imputil/importers.py
benjamin.peterson
python-3000-checkins at python.org
Fri Jun 6 00:53:41 CEST 2008
Author: benjamin.peterson
Date: Fri Jun 6 00:53:40 2008
New Revision: 63966
Log:
remove imputil demo
Removed:
python/branches/py3k/Demo/imputil/importers.py
Deleted: python/branches/py3k/Demo/imputil/importers.py
==============================================================================
--- python/branches/py3k/Demo/imputil/importers.py Fri Jun 6 00:53:40 2008
+++ (empty file)
@@ -1,248 +0,0 @@
-#
-# importers.py
-#
-# Demonstration subclasses of imputil.Importer
-#
-
-# There should be consideration for the imports below if it is desirable
-# to have "all" modules be imported through the imputil system.
-
-# these are C extensions
-import sys
-import imp
-import struct
-import marshal
-
-# these are .py modules
-import imputil
-import os
-
-######################################################################
-
-_TupleType = type(())
-_StringType = type('')
-
-######################################################################
-
-# byte-compiled file suffic character
-_suffix_char = __debug__ and 'c' or 'o'
-
-# byte-compiled file suffix
-_suffix = '.py' + _suffix_char
-
-# the C_EXTENSION suffixes
-_c_suffixes = [x for x in imp.get_suffixes() if x[2] == imp.C_EXTENSION]
-
-def _timestamp(pathname):
- "Return the file modification time as a Long."
- try:
- s = os.stat(pathname)
- except OSError:
- return None
- return int(s[8])
-
-def _fs_import(dir, modname, fqname):
- "Fetch a module from the filesystem."
-
- pathname = os.path.join(dir, modname)
- if os.path.isdir(pathname):
- values = { '__pkgdir__' : pathname, '__path__' : [ pathname ] }
- ispkg = 1
- pathname = os.path.join(pathname, '__init__')
- else:
- values = { }
- ispkg = 0
-
- # look for dynload modules
- for desc in _c_suffixes:
- file = pathname + desc[0]
- try:
- fp = open(file, desc[1])
- except IOError:
- pass
- else:
- module = imp.load_module(fqname, fp, file, desc)
- values['__file__'] = file
- return 0, module, values
-
- t_py = _timestamp(pathname + '.py')
- t_pyc = _timestamp(pathname + _suffix)
- if t_py is None and t_pyc is None:
- return None
- code = None
- if t_py is None or (t_pyc is not None and t_pyc >= t_py):
- file = pathname + _suffix
- f = open(file, 'rb')
- if f.read(4) == imp.get_magic():
- t = struct.unpack('<I', f.read(4))[0]
- if t == t_py:
- code = marshal.load(f)
- f.close()
- if code is None:
- file = pathname + '.py'
- code = _compile(file, t_py)
-
- values['__file__'] = file
- return ispkg, code, values
-
-######################################################################
-#
-# Simple function-based importer
-#
-class FuncImporter(imputil.Importer):
- "Importer subclass to delegate to a function rather than method overrides."
- def __init__(self, func):
- self.func = func
- def get_code(self, parent, modname, fqname):
- return self.func(parent, modname, fqname)
-
-def install_with(func):
- FuncImporter(func).install()
-
-
-######################################################################
-#
-# Base class for archive-based importing
-#
-class PackageArchiveImporter(imputil.Importer):
- """Importer subclass to import from (file) archives.
-
- This Importer handles imports of the style <archive>.<subfile>, where
- <archive> can be located using a subclass-specific mechanism and the
- <subfile> is found in the archive using a subclass-specific mechanism.
-
- This class defines two hooks for subclasses: one to locate an archive
- (and possibly return some context for future subfile lookups), and one
- to locate subfiles.
- """
-
- def get_code(self, parent, modname, fqname):
- if parent:
- # the Importer._finish_import logic ensures that we handle imports
- # under the top level module (package / archive).
- assert parent.__importer__ == self
-
- # if a parent "package" is provided, then we are importing a
- # sub-file from the archive.
- result = self.get_subfile(parent.__archive__, modname)
- if result is None:
- return None
- if isinstance(result, _TupleType):
- assert len(result) == 2
- return (0,) + result
- return 0, result, {}
-
- # no parent was provided, so the archive should exist somewhere on the
- # default "path".
- archive = self.get_archive(modname)
- if archive is None:
- return None
- return 1, "", {'__archive__':archive}
-
- def get_archive(self, modname):
- """Get an archive of modules.
-
- This method should locate an archive and return a value which can be
- used by get_subfile to load modules from it. The value may be a simple
- pathname, an open file, or a complex object that caches information
- for future imports.
-
- Return None if the archive was not found.
- """
- raise RuntimeError("get_archive not implemented")
-
- def get_subfile(self, archive, modname):
- """Get code from a subfile in the specified archive.
-
- Given the specified archive (as returned by get_archive()), locate
- and return a code object for the specified module name.
-
- A 2-tuple may be returned, consisting of a code object and a dict
- of name/values to place into the target module.
-
- Return None if the subfile was not found.
- """
- raise RuntimeError("get_subfile not implemented")
-
-
-class PackageArchive(PackageArchiveImporter):
- "PackageArchiveImporter subclass that refers to a specific archive."
-
- def __init__(self, modname, archive_pathname):
- self.__modname = modname
- self.__path = archive_pathname
-
- def get_archive(self, modname):
- if modname == self.__modname:
- return self.__path
- return None
-
- # get_subfile is passed the full pathname of the archive
-
-
-######################################################################
-#
-# Emulate the standard directory-based import mechanism
-#
-class DirectoryImporter(imputil.Importer):
- "Importer subclass to emulate the standard importer."
-
- def __init__(self, dir):
- self.dir = dir
-
- def get_code(self, parent, modname, fqname):
- if parent:
- dir = parent.__pkgdir__
- else:
- dir = self.dir
-
- # Return the module (and other info) if found in the specified
- # directory. Otherwise, return None.
- return _fs_import(dir, modname, fqname)
-
- def __repr__(self):
- return '<%s.%s for "%s" at 0x%x>' % (self.__class__.__module__,
- self.__class__.__name__,
- self.dir,
- id(self))
-
-
-######################################################################
-#
-# Emulate the standard path-style import mechanism
-#
-class PathImporter(imputil.Importer):
- def __init__(self, path=sys.path):
- self.path = path
-
- def get_code(self, parent, modname, fqname):
- if parent:
- # we are looking for a module inside of a specific package
- return _fs_import(parent.__pkgdir__, modname, fqname)
-
- # scan sys.path, looking for the requested module
- for dir in self.path:
- if isinstance(dir, _StringType):
- result = _fs_import(dir, modname, fqname)
- if result:
- return result
-
- # not found
- return None
-
-######################################################################
-
-def _test_dir():
- "Debug/test function to create DirectoryImporters from sys.path."
- imputil.ImportManager().install()
- path = sys.path[:]
- path.reverse()
- for d in path:
- sys.path.insert(0, DirectoryImporter(d))
- sys.path.insert(0, imputil.BuiltinImporter())
-
-def _test_revamp():
- "Debug/test function for the revamped import system."
- imputil.ImportManager().install()
- sys.path.insert(0, PathImporter())
- sys.path.insert(0, imputil.BuiltinImporter())
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