[Python-checkins] distutils2: Initial import of pkgutil module taken from Python 2.7a4. Also adding an
tarek.ziade
python-checkins at python.org
Mon Apr 5 23:09:19 CEST 2010
tarek.ziade pushed 2aec7cf93366 to distutils2:
http://hg.python.org/distutils2/rev/2aec7cf93366
changeset: 88:2aec7cf93366
user: pumazi
date: Tue Mar 30 20:40:11 2010 -0400
summary: Initial import of pkgutil module taken from Python 2.7a4. Also adding an accompanying test module.
files: src/distutils2/_backport/pkgutil.py, src/distutils2/_backport/tests/test_pkgutil.py
diff --git a/src/distutils2/_backport/pkgutil.py b/src/distutils2/_backport/pkgutil.py
new file mode 100644
--- /dev/null
+++ b/src/distutils2/_backport/pkgutil.py
@@ -0,0 +1,583 @@
+"""Utilities to support packages."""
+
+# NOTE: This module must remain compatible with Python 2.3, as it is shared
+# by setuptools for distribution with Python 2.3 and up.
+
+import os
+import sys
+import imp
+import os.path
+from types import ModuleType
+
+__all__ = [
+ 'get_importer', 'iter_importers', 'get_loader', 'find_loader',
+ 'walk_packages', 'iter_modules',
+ 'ImpImporter', 'ImpLoader', 'read_code', 'extend_path',
+]
+
+def read_code(stream):
+ # This helper is needed in order for the PEP 302 emulation to
+ # correctly handle compiled files
+ import marshal
+
+ magic = stream.read(4)
+ if magic != imp.get_magic():
+ return None
+
+ stream.read(4) # Skip timestamp
+ return marshal.load(stream)
+
+
+def simplegeneric(func):
+ """Make a trivial single-dispatch generic function"""
+ registry = {}
+ def wrapper(*args, **kw):
+ ob = args[0]
+ try:
+ cls = ob.__class__
+ except AttributeError:
+ cls = type(ob)
+ try:
+ mro = cls.__mro__
+ except AttributeError:
+ try:
+ class cls(cls, object):
+ pass
+ mro = cls.__mro__[1:]
+ except TypeError:
+ mro = object, # must be an ExtensionClass or some such :(
+ for t in mro:
+ if t in registry:
+ return registry[t](*args, **kw)
+ else:
+ return func(*args, **kw)
+ try:
+ wrapper.__name__ = func.__name__
+ except (TypeError, AttributeError):
+ pass # Python 2.3 doesn't allow functions to be renamed
+
+ def register(typ, func=None):
+ if func is None:
+ return lambda f: register(typ, f)
+ registry[typ] = func
+ return func
+
+ wrapper.__dict__ = func.__dict__
+ wrapper.__doc__ = func.__doc__
+ wrapper.register = register
+ return wrapper
+
+
+def walk_packages(path=None, prefix='', onerror=None):
+ """Yields (module_loader, name, ispkg) for all modules recursively
+ on path, or, if path is None, all accessible modules.
+
+ 'path' should be either None or a list of paths to look for
+ modules in.
+
+ 'prefix' is a string to output on the front of every module name
+ on output.
+
+ Note that this function must import all *packages* (NOT all
+ modules!) on the given path, in order to access the __path__
+ attribute to find submodules.
+
+ 'onerror' is a function which gets called with one argument (the
+ name of the package which was being imported) if any exception
+ occurs while trying to import a package. If no onerror function is
+ supplied, ImportErrors are caught and ignored, while all other
+ exceptions are propagated, terminating the search.
+
+ Examples:
+
+ # list all modules python can access
+ walk_packages()
+
+ # list all submodules of ctypes
+ walk_packages(ctypes.__path__, ctypes.__name__+'.')
+ """
+
+ def seen(p, m={}):
+ if p in m:
+ return True
+ m[p] = True
+
+ for importer, name, ispkg in iter_modules(path, prefix):
+ yield importer, name, ispkg
+
+ if ispkg:
+ try:
+ __import__(name)
+ except ImportError:
+ if onerror is not None:
+ onerror(name)
+ except Exception:
+ if onerror is not None:
+ onerror(name)
+ else:
+ raise
+ else:
+ path = getattr(sys.modules[name], '__path__', None) or []
+
+ # don't traverse path items we've seen before
+ path = [p for p in path if not seen(p)]
+
+ for item in walk_packages(path, name+'.', onerror):
+ yield item
+
+
+def iter_modules(path=None, prefix=''):
+ """Yields (module_loader, name, ispkg) for all submodules on path,
+ or, if path is None, all top-level modules on sys.path.
+
+ 'path' should be either None or a list of paths to look for
+ modules in.
+
+ 'prefix' is a string to output on the front of every module name
+ on output.
+ """
+
+ if path is None:
+ importers = iter_importers()
+ else:
+ importers = map(get_importer, path)
+
+ yielded = {}
+ for i in importers:
+ for name, ispkg in iter_importer_modules(i, prefix):
+ if name not in yielded:
+ yielded[name] = 1
+ yield i, name, ispkg
+
+
+#@simplegeneric
+def iter_importer_modules(importer, prefix=''):
+ if not hasattr(importer, 'iter_modules'):
+ return []
+ return importer.iter_modules(prefix)
+
+iter_importer_modules = simplegeneric(iter_importer_modules)
+
+
+class ImpImporter:
+ """PEP 302 Importer that wraps Python's "classic" import algorithm
+
+ ImpImporter(dirname) produces a PEP 302 importer that searches that
+ directory. ImpImporter(None) produces a PEP 302 importer that searches
+ the current sys.path, plus any modules that are frozen or built-in.
+
+ Note that ImpImporter does not currently support being used by placement
+ on sys.meta_path.
+ """
+
+ def __init__(self, path=None):
+ self.path = path
+
+ def find_module(self, fullname, path=None):
+ # Note: we ignore 'path' argument since it is only used via meta_path
+ subname = fullname.split(".")[-1]
+ if subname != fullname and self.path is None:
+ return None
+ if self.path is None:
+ path = None
+ else:
+ path = [os.path.realpath(self.path)]
+ try:
+ file, filename, etc = imp.find_module(subname, path)
+ except ImportError:
+ return None
+ return ImpLoader(fullname, file, filename, etc)
+
+ def iter_modules(self, prefix=''):
+ if self.path is None or not os.path.isdir(self.path):
+ return
+
+ yielded = {}
+ import inspect
+
+ filenames = os.listdir(self.path)
+ filenames.sort() # handle packages before same-named modules
+
+ for fn in filenames:
+ modname = inspect.getmodulename(fn)
+ if modname=='__init__' or modname in yielded:
+ continue
+
+ path = os.path.join(self.path, fn)
+ ispkg = False
+
+ if not modname and os.path.isdir(path) and '.' not in fn:
+ modname = fn
+ for fn in os.listdir(path):
+ subname = inspect.getmodulename(fn)
+ if subname=='__init__':
+ ispkg = True
+ break
+ else:
+ continue # not a package
+
+ if modname and '.' not in modname:
+ yielded[modname] = 1
+ yield prefix + modname, ispkg
+
+
+class ImpLoader:
+ """PEP 302 Loader that wraps Python's "classic" import algorithm
+ """
+ code = source = None
+
+ def __init__(self, fullname, file, filename, etc):
+ self.file = file
+ self.filename = filename
+ self.fullname = fullname
+ self.etc = etc
+
+ def load_module(self, fullname):
+ self._reopen()
+ try:
+ mod = imp.load_module(fullname, self.file, self.filename, self.etc)
+ finally:
+ if self.file:
+ self.file.close()
+ # Note: we don't set __loader__ because we want the module to look
+ # normal; i.e. this is just a wrapper for standard import machinery
+ return mod
+
+ def get_data(self, pathname):
+ return open(pathname, "rb").read()
+
+ def _reopen(self):
+ if self.file and self.file.closed:
+ mod_type = self.etc[2]
+ if mod_type==imp.PY_SOURCE:
+ self.file = open(self.filename, 'rU')
+ elif mod_type in (imp.PY_COMPILED, imp.C_EXTENSION):
+ self.file = open(self.filename, 'rb')
+
+ def _fix_name(self, fullname):
+ if fullname is None:
+ fullname = self.fullname
+ elif fullname != self.fullname:
+ raise ImportError("Loader for module %s cannot handle "
+ "module %s" % (self.fullname, fullname))
+ return fullname
+
+ def is_package(self, fullname):
+ fullname = self._fix_name(fullname)
+ return self.etc[2]==imp.PKG_DIRECTORY
+
+ def get_code(self, fullname=None):
+ fullname = self._fix_name(fullname)
+ if self.code is None:
+ mod_type = self.etc[2]
+ if mod_type==imp.PY_SOURCE:
+ source = self.get_source(fullname)
+ self.code = compile(source, self.filename, 'exec')
+ elif mod_type==imp.PY_COMPILED:
+ self._reopen()
+ try:
+ self.code = read_code(self.file)
+ finally:
+ self.file.close()
+ elif mod_type==imp.PKG_DIRECTORY:
+ self.code = self._get_delegate().get_code()
+ return self.code
+
+ def get_source(self, fullname=None):
+ fullname = self._fix_name(fullname)
+ if self.source is None:
+ mod_type = self.etc[2]
+ if mod_type==imp.PY_SOURCE:
+ self._reopen()
+ try:
+ self.source = self.file.read()
+ finally:
+ self.file.close()
+ elif mod_type==imp.PY_COMPILED:
+ if os.path.exists(self.filename[:-1]):
+ f = open(self.filename[:-1], 'rU')
+ self.source = f.read()
+ f.close()
+ elif mod_type==imp.PKG_DIRECTORY:
+ self.source = self._get_delegate().get_source()
+ return self.source
+
+
+ def _get_delegate(self):
+ return ImpImporter(self.filename).find_module('__init__')
+
+ def get_filename(self, fullname=None):
+ fullname = self._fix_name(fullname)
+ mod_type = self.etc[2]
+ if self.etc[2]==imp.PKG_DIRECTORY:
+ return self._get_delegate().get_filename()
+ elif self.etc[2] in (imp.PY_SOURCE, imp.PY_COMPILED, imp.C_EXTENSION):
+ return self.filename
+ return None
+
+
+try:
+ import zipimport
+ from zipimport import zipimporter
+
+ def iter_zipimport_modules(importer, prefix=''):
+ dirlist = zipimport._zip_directory_cache[importer.archive].keys()
+ dirlist.sort()
+ _prefix = importer.prefix
+ plen = len(_prefix)
+ yielded = {}
+ import inspect
+ for fn in dirlist:
+ if not fn.startswith(_prefix):
+ continue
+
+ fn = fn[plen:].split(os.sep)
+
+ if len(fn)==2 and fn[1].startswith('__init__.py'):
+ if fn[0] not in yielded:
+ yielded[fn[0]] = 1
+ yield fn[0], True
+
+ if len(fn)!=1:
+ continue
+
+ modname = inspect.getmodulename(fn[0])
+ if modname=='__init__':
+ continue
+
+ if modname and '.' not in modname and modname not in yielded:
+ yielded[modname] = 1
+ yield prefix + modname, False
+
+ iter_importer_modules.register(zipimporter, iter_zipimport_modules)
+
+except ImportError:
+ pass
+
+
+def get_importer(path_item):
+ """Retrieve a PEP 302 importer for the given path item
+
+ The returned importer is cached in sys.path_importer_cache
+ if it was newly created by a path hook.
+
+ If there is no importer, a wrapper around the basic import
+ machinery is returned. This wrapper is never inserted into
+ the importer cache (None is inserted instead).
+
+ The cache (or part of it) can be cleared manually if a
+ rescan of sys.path_hooks is necessary.
+ """
+ try:
+ importer = sys.path_importer_cache[path_item]
+ except KeyError:
+ for path_hook in sys.path_hooks:
+ try:
+ importer = path_hook(path_item)
+ break
+ except ImportError:
+ pass
+ else:
+ importer = None
+ sys.path_importer_cache.setdefault(path_item, importer)
+
+ if importer is None:
+ try:
+ importer = ImpImporter(path_item)
+ except ImportError:
+ importer = None
+ return importer
+
+
+def iter_importers(fullname=""):
+ """Yield PEP 302 importers for the given module name
+
+ If fullname contains a '.', the importers will be for the package
+ containing fullname, otherwise they will be importers for sys.meta_path,
+ sys.path, and Python's "classic" import machinery, in that order. If
+ the named module is in a package, that package is imported as a side
+ effect of invoking this function.
+
+ Non PEP 302 mechanisms (e.g. the Windows registry) used by the
+ standard import machinery to find files in alternative locations
+ are partially supported, but are searched AFTER sys.path. Normally,
+ these locations are searched BEFORE sys.path, preventing sys.path
+ entries from shadowing them.
+
+ For this to cause a visible difference in behaviour, there must
+ be a module or package name that is accessible via both sys.path
+ and one of the non PEP 302 file system mechanisms. In this case,
+ the emulation will find the former version, while the builtin
+ import mechanism will find the latter.
+
+ Items of the following types can be affected by this discrepancy:
+ imp.C_EXTENSION, imp.PY_SOURCE, imp.PY_COMPILED, imp.PKG_DIRECTORY
+ """
+ if fullname.startswith('.'):
+ raise ImportError("Relative module names not supported")
+ if '.' in fullname:
+ # Get the containing package's __path__
+ pkg = '.'.join(fullname.split('.')[:-1])
+ if pkg not in sys.modules:
+ __import__(pkg)
+ path = getattr(sys.modules[pkg], '__path__', None) or []
+ else:
+ for importer in sys.meta_path:
+ yield importer
+ path = sys.path
+ for item in path:
+ yield get_importer(item)
+ if '.' not in fullname:
+ yield ImpImporter()
+
+def get_loader(module_or_name):
+ """Get a PEP 302 "loader" object for module_or_name
+
+ If the module or package is accessible via the normal import
+ mechanism, a wrapper around the relevant part of that machinery
+ is returned. Returns None if the module cannot be found or imported.
+ If the named module is not already imported, its containing package
+ (if any) is imported, in order to establish the package __path__.
+
+ This function uses iter_importers(), and is thus subject to the same
+ limitations regarding platform-specific special import locations such
+ as the Windows registry.
+ """
+ if module_or_name in sys.modules:
+ module_or_name = sys.modules[module_or_name]
+ if isinstance(module_or_name, ModuleType):
+ module = module_or_name
+ loader = getattr(module, '__loader__', None)
+ if loader is not None:
+ return loader
+ fullname = module.__name__
+ else:
+ fullname = module_or_name
+ return find_loader(fullname)
+
+def find_loader(fullname):
+ """Find a PEP 302 "loader" object for fullname
+
+ If fullname contains dots, path must be the containing package's __path__.
+ Returns None if the module cannot be found or imported. This function uses
+ iter_importers(), and is thus subject to the same limitations regarding
+ platform-specific special import locations such as the Windows registry.
+ """
+ for importer in iter_importers(fullname):
+ loader = importer.find_module(fullname)
+ if loader is not None:
+ return loader
+
+ return None
+
+
+def extend_path(path, name):
+ """Extend a package's path.
+
+ Intended use is to place the following code in a package's __init__.py:
+
+ from pkgutil import extend_path
+ __path__ = extend_path(__path__, __name__)
+
+ This will add to the package's __path__ all subdirectories of
+ directories on sys.path named after the package. This is useful
+ if one wants to distribute different parts of a single logical
+ package as multiple directories.
+
+ It also looks for *.pkg files beginning where * matches the name
+ argument. This feature is similar to *.pth files (see site.py),
+ except that it doesn't special-case lines starting with 'import'.
+ A *.pkg file is trusted at face value: apart from checking for
+ duplicates, all entries found in a *.pkg file are added to the
+ path, regardless of whether they are exist the filesystem. (This
+ is a feature.)
+
+ If the input path is not a list (as is the case for frozen
+ packages) it is returned unchanged. The input path is not
+ modified; an extended copy is returned. Items are only appended
+ to the copy at the end.
+
+ It is assumed that sys.path is a sequence. Items of sys.path that
+ are not (unicode or 8-bit) strings referring to existing
+ directories are ignored. Unicode items of sys.path that cause
+ errors when used as filenames may cause this function to raise an
+ exception (in line with os.path.isdir() behavior).
+ """
+
+ if not isinstance(path, list):
+ # This could happen e.g. when this is called from inside a
+ # frozen package. Return the path unchanged in that case.
+ return path
+
+ pname = os.path.join(*name.split('.')) # Reconstitute as relative path
+ # Just in case os.extsep != '.'
+ sname = os.extsep.join(name.split('.'))
+ sname_pkg = sname + os.extsep + "pkg"
+ init_py = "__init__" + os.extsep + "py"
+
+ path = path[:] # Start with a copy of the existing path
+
+ for dir in sys.path:
+ if not isinstance(dir, basestring) or not os.path.isdir(dir):
+ continue
+ subdir = os.path.join(dir, pname)
+ # XXX This may still add duplicate entries to path on
+ # case-insensitive filesystems
+ initfile = os.path.join(subdir, init_py)
+ if subdir not in path and os.path.isfile(initfile):
+ path.append(subdir)
+ # XXX Is this the right thing for subpackages like zope.app?
+ # It looks for a file named "zope.app.pkg"
+ pkgfile = os.path.join(dir, sname_pkg)
+ if os.path.isfile(pkgfile):
+ try:
+ f = open(pkgfile)
+ except IOError, msg:
+ sys.stderr.write("Can't open %s: %s\n" %
+ (pkgfile, msg))
+ else:
+ for line in f:
+ line = line.rstrip('\n')
+ if not line or line.startswith('#'):
+ continue
+ path.append(line) # Don't check for existence!
+ f.close()
+
+ return path
+
+def get_data(package, resource):
+ """Get a resource from a package.
+
+ This is a wrapper round the PEP 302 loader get_data API. The package
+ argument should be the name of a package, in standard module format
+ (foo.bar). The resource argument should be in the form of a relative
+ filename, using '/' as the path separator. The parent directory name '..'
+ is not allowed, and nor is a rooted name (starting with a '/').
+
+ The function returns a binary string, which is the contents of the
+ specified resource.
+
+ For packages located in the filesystem, which have already been imported,
+ this is the rough equivalent of
+
+ d = os.path.dirname(sys.modules[package].__file__)
+ data = open(os.path.join(d, resource), 'rb').read()
+
+ If the package cannot be located or loaded, or it uses a PEP 302 loader
+ which does not support get_data(), then None is returned.
+ """
+
+ loader = get_loader(package)
+ if loader is None or not hasattr(loader, 'get_data'):
+ return None
+ mod = sys.modules.get(package) or loader.load_module(package)
+ if mod is None or not hasattr(mod, '__file__'):
+ return None
+
+ # Modify the resource name to be compatible with the loader.get_data
+ # signature - an os.path format "filename" starting with the dirname of
+ # the package's __file__
+ parts = resource.split('/')
+ parts.insert(0, os.path.dirname(mod.__file__))
+ resource_name = os.path.join(*parts)
+ return loader.get_data(resource_name)
diff --git a/src/distutils2/_backport/tests/test_pkgutil.py b/src/distutils2/_backport/tests/test_pkgutil.py
new file mode 100644
--- /dev/null
+++ b/src/distutils2/_backport/tests/test_pkgutil.py
@@ -0,0 +1,31 @@
+# -*- coding: utf-8 -*-
+"""Tests for PEP 376 pkgutil functionality"""
+import unittest2
+import sys
+import os
+
+from test.test_support import run_unittest, TESTFN
+
+import distutils2._backport.pkgutil
+
+class TestPkgUtil(unittest2.TestCase):
+ """Tests for the new functionality added in PEP 376."""
+
+ # def setUp(self):
+ # super(TestPkgUtil, self).setUp()
+
+ # def tearDown(self):
+ # super(TestPkgUtil, self).tearDown()
+
+ def test_something(self):
+ pass
+
+
+def test_suite():
+ return unittest2.makeSuite(TestPkgUtil)
+
+def test_main():
+ run_unittest(test_suite())
+
+if __name__ == "__main__":
+ test_main()
--
Repository URL: http://hg.python.org/distutils2
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