diff options
Diffstat (limited to 'Lib/pkgutil.py')
| -rw-r--r-- | Lib/pkgutil.py | 188 |
1 files changed, 121 insertions, 67 deletions
diff --git a/Lib/pkgutil.py b/Lib/pkgutil.py index 51da0b1bb5..20e6498942 100644 --- a/Lib/pkgutil.py +++ b/Lib/pkgutil.py @@ -2,8 +2,10 @@ import os import sys +import importlib import imp import os.path +from warnings import warn from types import ModuleType __all__ = [ @@ -21,7 +23,7 @@ def read_code(stream): if magic != imp.get_magic(): return None - stream.read(4) # Skip timestamp + stream.read(8) # Skip timestamp and size return marshal.load(stream) @@ -155,6 +157,49 @@ def iter_importer_modules(importer, prefix=''): iter_importer_modules = simplegeneric(iter_importer_modules) +# Implement a file walker for the normal importlib path hook +def _iter_file_finder_modules(importer, prefix=''): + if importer.path is None or not os.path.isdir(importer.path): + return + + yielded = {} + import inspect + try: + filenames = os.listdir(importer.path) + except OSError: + # ignore unreadable directories like import does + filenames = [] + 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(importer.path, fn) + ispkg = False + + if not modname and os.path.isdir(path) and '.' not in fn: + modname = fn + try: + dircontents = os.listdir(path) + except OSError: + # ignore unreadable directories like import does + dircontents = [] + for fn in dircontents: + 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 + +iter_importer_modules.register( + importlib.machinery.FileFinder, _iter_file_finder_modules) class ImpImporter: """PEP 302 Importer that wraps Python's "classic" import algorithm @@ -168,6 +213,8 @@ class ImpImporter: """ def __init__(self, path=None): + warn("This emulation is deprecated, use 'importlib' instead", + DeprecationWarning) self.path = path def find_module(self, fullname, path=None): @@ -232,6 +279,8 @@ class ImpLoader: code = source = None def __init__(self, fullname, file, filename, etc): + warn("This emulation is deprecated, use 'importlib' instead", + DeprecationWarning) self.file = file self.filename = filename self.fullname = fullname @@ -256,7 +305,7 @@ class ImpLoader: if self.file and self.file.closed: mod_type = self.etc[2] if mod_type==imp.PY_SOURCE: - self.file = open(self.filename, 'rU') + self.file = open(self.filename, 'r') elif mod_type in (imp.PY_COMPILED, imp.C_EXTENSION): self.file = open(self.filename, 'rb') @@ -301,7 +350,7 @@ class ImpLoader: self.file.close() elif mod_type==imp.PY_COMPILED: if os.path.exists(self.filename[:-1]): - f = open(self.filename[:-1], 'rU') + f = open(self.filename[:-1], 'r') self.source = f.read() f.close() elif mod_type==imp.PKG_DIRECTORY: @@ -315,9 +364,9 @@ class ImpLoader: def get_filename(self, fullname=None): fullname = self._fix_name(fullname) mod_type = self.etc[2] - if self.etc[2]==imp.PKG_DIRECTORY: + if mod_type==imp.PKG_DIRECTORY: return self._get_delegate().get_filename() - elif self.etc[2] in (imp.PY_SOURCE, imp.PY_COMPILED, imp.C_EXTENSION): + elif mod_type in (imp.PY_SOURCE, imp.PY_COMPILED, imp.C_EXTENSION): return self.filename return None @@ -366,10 +415,6 @@ def get_importer(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. """ @@ -379,18 +424,12 @@ def get_importer(path_item): for path_hook in sys.path_hooks: try: importer = path_hook(path_item) + sys.path_importer_cache.setdefault(path_item, importer) 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 @@ -398,55 +437,37 @@ 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. + containing fullname, otherwise they will be all registered top level + importers (i.e. those on both sys.meta_path and sys.path_hooks). - 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. + If the named module is in a package, that package is imported as a side + effect of invoking this function. - Items of the following types can be affected by this discrepancy: - imp.C_EXTENSION, imp.PY_SOURCE, imp.PY_COMPILED, imp.PKG_DIRECTORY + If no module name is specified, all top level importers are produced. """ if fullname.startswith('.'): - raise ImportError("Relative module names not supported") + msg = "Relative module name {!r} not supported".format(fullname) + raise ImportError(msg) 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 [] + pkg_name = fullname.rpartition(".")[0] + pkg = importlib.import_module(pkg_name) + path = getattr(pkg, '__path__', None) + if path is None: + return 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. + 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] @@ -460,20 +481,33 @@ def get_loader(module_or_name): 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. + This is s convenience wrapper around :func:`importlib.find_loader` that + sets the *path* argument correctly when searching for submodules, and + also ensures parent packages (if any) are imported before searching for + submodules. """ - for importer in iter_importers(fullname): - loader = importer.find_module(fullname) - if loader is not None: - return loader - - return None + if fullname.startswith('.'): + msg = "Relative module name {!r} not supported".format(fullname) + raise ImportError(msg) + path = None + pkg_name = fullname.rpartition(".")[0] + if pkg_name: + pkg = importlib.import_module(pkg_name) + path = getattr(pkg, "__path__", None) + if path is None: + return None + try: + return importlib.find_loader(fullname, path) + except (ImportError, AttributeError, TypeError, ValueError) as ex: + # This hack fixes an impedance mismatch between pkgutil and + # importlib, where the latter raises other errors for cases where + # pkgutil previously raised ImportError + msg = "Error while finding loader for {!r} ({}: {})" + raise ImportError(msg.format(fullname, type(ex), ex)) from ex def extend_path(path, name): @@ -514,21 +548,41 @@ def extend_path(path, name): # frozen package. Return the path unchanged in that case. return path - pname = os.path.join(*name.split('.')) # Reconstitute as relative path sname_pkg = name + ".pkg" - init_py = "__init__.py" path = path[:] # Start with a copy of the existing path - for dir in sys.path: - if not isinstance(dir, str) or not os.path.isdir(dir): + parent_package, _, final_name = name.rpartition('.') + if parent_package: + try: + search_path = sys.modules[parent_package].__path__ + except (KeyError, AttributeError): + # We can't do anything: find_loader() returns None when + # passed a dotted name. + return path + else: + search_path = sys.path + + for dir in search_path: + if not isinstance(dir, str): 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) + + finder = get_importer(dir) + if finder is not None: + # Is this finder PEP 420 compliant? + if hasattr(finder, 'find_loader'): + loader, portions = finder.find_loader(final_name) + else: + # No, no need to call it + loader = None + portions = [] + + for portion in portions: + # XXX This may still add duplicate entries to path on + # case-insensitive filesystems + if portion not in path: + path.append(portion) + # 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) |