Add pylint to depot_tools.

third_party/logilab/common/modutils.py

+# -*- coding: utf-8 -*-
+# copyright 2003-2011 LOGILAB S.A. (Paris, FRANCE), all rights reserved.
+# contact http://www.logilab.fr/ -- mailto:contact@logilab.fr
+#
+# This file is part of logilab-common.
+#
+# logilab-common is free software: you can redistribute it and/or modify it under
+# the terms of the GNU Lesser General Public License as published by the Free
+# Software Foundation, either version 2.1 of the License, or (at your option) any
+# later version.
+#
+# logilab-common is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+# FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more
+# details.
+#
+# You should have received a copy of the GNU Lesser General Public License along
+# with logilab-common.  If not, see <http://www.gnu.org/licenses/>.
+"""Python modules manipulation utility functions.
+
+:type PY_SOURCE_EXTS: tuple(str)
+:var PY_SOURCE_EXTS: list of possible python source file extension
+
+:type STD_LIB_DIR: str
+:var STD_LIB_DIR: directory where standard modules are located
+
+:type BUILTIN_MODULES: dict
+:var BUILTIN_MODULES: dictionary with builtin module names has key
+"""
+__docformat__ = "restructuredtext en"
+
+import sys
+import os
+from os.path import splitext, join, abspath, isdir, dirname, exists, basename
+from imp import find_module, load_module, C_BUILTIN, PY_COMPILED, PKG_DIRECTORY
+from distutils.sysconfig import get_config_var, get_python_lib, get_python_version
+
+try:
+    import zipimport
+except ImportError:
+    zipimport = None
+
+ZIPFILE = object()
+
+from logilab.common import STD_BLACKLIST, _handle_blacklist
+
+# Notes about STD_LIB_DIR
+# Consider arch-specific installation for STD_LIB_DIR definition
+# :mod:`distutils.sysconfig` contains to much hardcoded values to rely on
+#
+# :see: `Problems with /usr/lib64 builds <http://bugs.python.org/issue1294959>`_
+# :see: `FHS <http://www.pathname.com/fhs/pub/fhs-2.3.html#LIBLTQUALGTALTERNATEFORMATESSENTIAL>`_
+if sys.platform.startswith('win'):
+    PY_SOURCE_EXTS = ('py', 'pyw')
+    PY_COMPILED_EXTS = ('dll', 'pyd')
+    STD_LIB_DIR = get_python_lib(standard_lib=1)
+else:
+    PY_SOURCE_EXTS = ('py',)
+    PY_COMPILED_EXTS = ('so',)
+    # extend lib dir with some arch-dependant paths
+    STD_LIB_DIR = join(get_config_var("LIBDIR"), "python%s" % get_python_version())
+
+BUILTIN_MODULES = dict(zip(sys.builtin_module_names,
+                           [1]*len(sys.builtin_module_names)))
+
+
+class NoSourceFile(Exception):
+    """exception raised when we are not able to get a python
+    source file for a precompiled file
+    """
+
+class LazyObject(object):
+    def __init__(self, module, obj):
+        self.module = module
+        self.obj = obj
+        self._imported = None
+
+    def _getobj(self):
+        if self._imported is None:
+           self._imported = getattr(load_module_from_name(self.module),
+                                    self.obj)
+        return self._imported
+
+    def __getattribute__(self, attr):
+        try:
+            return super(LazyObject, self).__getattribute__(attr)
+        except AttributeError, ex:
+            return getattr(self._getobj(), attr)
+
+    def __call__(self, *args, **kwargs):
+        return self._getobj()(*args, **kwargs)
+
+
+def load_module_from_name(dotted_name, path=None, use_sys=1):
+    """Load a Python module from it's name.
+
+    :type dotted_name: str
+    :param dotted_name: python name of a module or package
+
+    :type path: list or None
+    :param path:
+      optional list of path where the module or package should be
+      searched (use sys.path if nothing or None is given)
+
+    :type use_sys: bool
+    :param use_sys:
+      boolean indicating whether the sys.modules dictionary should be
+      used or not
+
+
+    :raise ImportError: if the module or package is not found
+
+    :rtype: module
+    :return: the loaded module
+    """
+    return load_module_from_modpath(dotted_name.split('.'), path, use_sys)
+
+
+def load_module_from_modpath(parts, path=None, use_sys=1):
+    """Load a python module from it's splitted name.
+
+    :type parts: list(str) or tuple(str)
+    :param parts:
+      python name of a module or package splitted on '.'
+
+    :type path: list or None
+    :param path:
+      optional list of path where the module or package should be
+      searched (use sys.path if nothing or None is given)
+
+    :type use_sys: bool
+    :param use_sys:
+      boolean indicating whether the sys.modules dictionary should be used or not
+
+    :raise ImportError: if the module or package is not found
+
+    :rtype: module
+    :return: the loaded module
+    """
+    if use_sys:
+        try:
+            return sys.modules['.'.join(parts)]
+        except KeyError:
+            pass
+    modpath = []
+    prevmodule = None
+    for part in parts:
+        modpath.append(part)
+        curname = '.'.join(modpath)
+        module = None
+        if len(modpath) != len(parts):
+            # even with use_sys=False, should try to get outer packages from sys.modules
+            module = sys.modules.get(curname)
+        if module is None:
+            mp_file, mp_filename, mp_desc = find_module(part, path)
+            module = load_module(curname, mp_file, mp_filename, mp_desc)
+        if prevmodule:
+            setattr(prevmodule, part, module)
+        _file = getattr(module, '__file__', '')
+        if not _file and len(modpath) != len(parts):
+            raise ImportError('no module in %s' % '.'.join(parts[len(modpath):]) )
+        path = [dirname( _file )]
+        prevmodule = module
+    return module
+
+
+def load_module_from_file(filepath, path=None, use_sys=1, extrapath=None):
+    """Load a Python module from it's path.
+
+    :type filepath: str
+    :param filepath: path to the python module or package
+
+    :type path: list or None
+    :param path:
+      optional list of path where the module or package should be
+      searched (use sys.path if nothing or None is given)
+
+    :type use_sys: bool
+    :param use_sys:
+      boolean indicating whether the sys.modules dictionary should be
+      used or not
+
+
+    :raise ImportError: if the module or package is not found
+
+    :rtype: module
+    :return: the loaded module
+    """
+    modpath = modpath_from_file(filepath, extrapath)
+    return load_module_from_modpath(modpath, path, use_sys)
+
+
+def _check_init(path, mod_path):
+    """check there are some __init__.py all along the way"""
+    for part in mod_path:
+        path = join(path, part)
+        if not _has_init(path):
+            return False
+    return True
+
+
+def modpath_from_file(filename, extrapath=None):
+    """given a file path return the corresponding splitted module's name
+    (i.e name of a module or package splitted on '.')
+
+    :type filename: str
+    :param filename: file's path for which we want the module's name
+
+    :type extrapath: dict
+    :param extrapath:
+      optional extra search path, with path as key and package name for the path
+      as value. This is usually useful to handle package splitted in multiple
+      directories using __path__ trick.
+
+
+    :raise ImportError:
+      if the corresponding module's name has not been found
+
+    :rtype: list(str)
+    :return: the corresponding splitted module's name
+    """
+    base = splitext(abspath(filename))[0]
+    if extrapath is not None:
+        for path_ in extrapath:
+            path = abspath(path_)
+            if path and base[:len(path)] == path:
+                submodpath = [pkg for pkg in base[len(path):].split(os.sep)
+                              if pkg]
+                if _check_init(path, submodpath[:-1]):
+                    return extrapath[path_].split('.') + submodpath
+    for path in sys.path:
+        path = abspath(path)
+        if path and base[:len(path)] == path:
+            if filename.find('site-packages') != -1 and \
+                   path.find('site-packages') == -1:
+                continue
+            modpath = [pkg for pkg in base[len(path):].split(os.sep) if pkg]
+            if _check_init(path, modpath[:-1]):
+                return modpath
+    raise ImportError('Unable to find module for %s in %s' % (
+        filename, ', \n'.join(sys.path)))
+
+
+
+def file_from_modpath(modpath, path=None, context_file=None):
+    """given a mod path (i.e. splitted module / package name), return the
+    corresponding file, giving priority to source file over precompiled
+    file if it exists
+
+    :type modpath: list or tuple
+    :param modpath:
+      splitted module's name (i.e name of a module or package splitted
+      on '.')
+      (this means explicit relative imports that start with dots have
+      empty strings in this list!)
+
+    :type path: list or None
+    :param path:
+      optional list of path where the module or package should be
+      searched (use sys.path if nothing or None is given)
+
+    :type context_file: str or None
+    :param context_file:
+      context file to consider, necessary if the identifier has been
+      introduced using a relative import unresolvable in the actual
+      context (i.e. modutils)
+
+    :raise ImportError: if there is no such module in the directory
+
+    :rtype: str or None
+    :return:
+      the path to the module's file or None if it's an integrated
+      builtin module such as 'sys'
+    """
+    if context_file is not None:
+        context = dirname(context_file)
+    else:
+        context = context_file
+    if modpath[0] == 'xml':
+        # handle _xmlplus
+        try:
+            return _file_from_modpath(['_xmlplus'] + modpath[1:], path, context)
+        except ImportError:
+            return _file_from_modpath(modpath, path, context)
+    elif modpath == ['os', 'path']:
+        # FIXME: currently ignoring search_path...
+        return os.path.__file__
+    return _file_from_modpath(modpath, path, context)
+
+
+
+def get_module_part(dotted_name, context_file=None):
+    """given a dotted name return the module part of the name :
+
+    >>> get_module_part('logilab.common.modutils.get_module_part')
+    'logilab.common.modutils'
+
+    :type dotted_name: str
+    :param dotted_name: full name of the identifier we are interested in
+
+    :type context_file: str or None
+    :param context_file:
+      context file to consider, necessary if the identifier has been
+      introduced using a relative import unresolvable in the actual
+      context (i.e. modutils)
+
+
+    :raise ImportError: if there is no such module in the directory
+
+    :rtype: str or None
+    :return:
+      the module part of the name or None if we have not been able at
+      all to import the given name
+
+    XXX: deprecated, since it doesn't handle package precedence over module
+    (see #10066)
+    """
+    # os.path trick
+    if dotted_name.startswith('os.path'):
+        return 'os.path'
+    parts = dotted_name.split('.')
+    if context_file is not None:
+        # first check for builtin module which won't be considered latter
+        # in that case (path != None)
+        if parts[0] in BUILTIN_MODULES:
+            if len(parts) > 2:
+                raise ImportError(dotted_name)
+            return parts[0]
+        # don't use += or insert, we want a new list to be created !
+    path = None
+    starti = 0
+    if parts[0] == '':
+        assert context_file is not None, \
+                'explicit relative import, but no context_file?'
+        path = [] # prevent resolving the import non-relatively
+        starti = 1
+    while parts[starti] == '': # for all further dots: change context
+        starti += 1
+        context_file = dirname(context_file)
+    for i in range(starti, len(parts)):
+        try:
+            file_from_modpath(parts[starti:i+1],
+                    path=path, context_file=context_file)
+        except ImportError:
+            if not i >= max(1, len(parts) - 2):
+                raise
+            return '.'.join(parts[:i])
+    return dotted_name
+
+
+def get_modules(package, src_directory, blacklist=STD_BLACKLIST):
+    """given a package directory return a list of all available python
+    modules in the package and its subpackages
+
+    :type package: str
+    :param package: the python name for the package
+
+    :type src_directory: str
+    :param src_directory:
+      path of the directory corresponding to the package
+
+    :type blacklist: list or tuple
+    :param blacklist:
+      optional list of files or directory to ignore, default to
+      the value of `logilab.common.STD_BLACKLIST`
+
+    :rtype: list
+    :return:
+      the list of all available python modules in the package and its
+      subpackages
+    """
+    modules = []
+    for directory, dirnames, filenames in os.walk(src_directory):
+        _handle_blacklist(blacklist, dirnames, filenames)
+        # check for __init__.py
+        if not '__init__.py' in filenames:
+            dirnames[:] = ()
+            continue
+        if directory != src_directory:
+            dir_package = directory[len(src_directory):].replace(os.sep, '.')
+            modules.append(package + dir_package)
+        for filename in filenames:
+            if _is_python_file(filename) and filename != '__init__.py':
+                src = join(directory, filename)
+                module = package + src[len(src_directory):-3]
+                modules.append(module.replace(os.sep, '.'))
+    return modules
+
+
+
+def get_module_files(src_directory, blacklist=STD_BLACKLIST):
+    """given a package directory return a list of all available python
+    module's files in the package and its subpackages
+
+    :type src_directory: str
+    :param src_directory:
+      path of the directory corresponding to the package
+
+    :type blacklist: list or tuple
+    :param blacklist:
+      optional list of files or directory to ignore, default to the value of
+      `logilab.common.STD_BLACKLIST`
+
+    :rtype: list
+    :return:
+      the list of all available python module's files in the package and
+      its subpackages
+    """
+    files = []
+    for directory, dirnames, filenames in os.walk(src_directory):
+        _handle_blacklist(blacklist, dirnames, filenames)
+        # check for __init__.py
+        if not '__init__.py' in filenames:
+            dirnames[:] = ()
+            continue
+        for filename in filenames:
+            if _is_python_file(filename):
+                src = join(directory, filename)
+                files.append(src)
+    return files
+
+
+def get_source_file(filename, include_no_ext=False):
+    """given a python module's file name return the matching source file
+    name (the filename will be returned identically if it's a already an
+    absolute path to a python source file...)
+
+    :type filename: str
+    :param filename: python module's file name
+
+
+    :raise NoSourceFile: if no source file exists on the file system
+
+    :rtype: str
+    :return: the absolute path of the source file if it exists
+    """
+    base, orig_ext = splitext(abspath(filename))
+    for ext in PY_SOURCE_EXTS:
+        source_path = '%s.%s' % (base, ext)
+        if exists(source_path):
+            return source_path
+    if include_no_ext and not orig_ext and exists(base):
+        return base
+    raise NoSourceFile(filename)
+
+
+def cleanup_sys_modules(directories):
+    """remove submodules of `directories` from `sys.modules`"""
+    for modname, module in sys.modules.items():
+        modfile = getattr(module, '__file__', None)
+        if modfile:
+            for directory in directories:
+                if modfile.startswith(directory):
+                    del sys.modules[modname]
+                    break
+
+
+def is_python_source(filename):
+    """
+    rtype: bool
+    return: True if the filename is a python source file
+    """
+    return splitext(filename)[1][1:] in PY_SOURCE_EXTS
+
+
+
+def is_standard_module(modname, std_path=(STD_LIB_DIR,)):
+    """try to guess if a module is a standard python module (by default,
+    see `std_path` parameter's description)
+
+    :type modname: str
+    :param modname: name of the module we are interested in
+
+    :type std_path: list(str) or tuple(str)
+    :param std_path: list of path considered has standard
+
+
+    :rtype: bool
+    :return:
+      true if the module:
+      - is located on the path listed in one of the directory in `std_path`
+      - is a built-in module
+    """
+    modname = modname.split('.')[0]
+    try:
+        filename = file_from_modpath([modname])
+    except ImportError, ex:
+        # import failed, i'm probably not so wrong by supposing it's
+        # not standard...
+        return 0
+    # modules which are not living in a file are considered standard
+    # (sys and __builtin__ for instance)
+    if filename is None:
+        return 1
+    filename = abspath(filename)
+    for path in std_path:
+        path = abspath(path)
+        if filename.startswith(path):
+            pfx_len = len(path)
+            if filename[pfx_len+1:pfx_len+14] != 'site-packages':
+                return 1
+            return 0
+    return False
+
+
+
+def is_relative(modname, from_file):
+    """return true if the given module name is relative to the given
+    file name
+
+    :type modname: str
+    :param modname: name of the module we are interested in
+
+    :type from_file: str
+    :param from_file:
+      path of the module from which modname has been imported
+
+    :rtype: bool
+    :return:
+      true if the module has been imported relatively to `from_file`
+    """
+    if not isdir(from_file):
+        from_file = dirname(from_file)
+    if from_file in sys.path:
+        return False
+    try:
+        find_module(modname.split('.')[0], [from_file])
+        return True
+    except ImportError:
+        return False
+
+
+# internal only functions #####################################################
+
+def _file_from_modpath(modpath, path=None, context=None):
+    """given a mod path (i.e. splitted module / package name), return the
+    corresponding file
+
+    this function is used internally, see `file_from_modpath`'s
+    documentation for more information
+    """
+    assert len(modpath) > 0
+    if context is not None:
+        try:
+            mtype, mp_filename = _module_file(modpath, [context])
+        except ImportError:
+            mtype, mp_filename = _module_file(modpath, path)
+    else:
+        mtype, mp_filename = _module_file(modpath, path)
+    if mtype == PY_COMPILED:
+        try:
+            return get_source_file(mp_filename)
+        except NoSourceFile:
+            return mp_filename
+    elif mtype == C_BUILTIN:
+        # integrated builtin module
+        return None
+    elif mtype == PKG_DIRECTORY:
+        mp_filename = _has_init(mp_filename)
+    return mp_filename
+
+def _search_zip(modpath, pic):
+    for filepath, importer in pic.items():
+        if importer is not None:
+            if importer.find_module(modpath[0]):
+                if not importer.find_module('/'.join(modpath)):
+                    raise ImportError('No module named %s in %s/%s' % (
+                        '.'.join(modpath[1:]), file, modpath))
+                return ZIPFILE, abspath(filepath) + '/' + '/'.join(modpath), filepath
+    raise ImportError('No module named %s' % '.'.join(modpath))
+
+def _module_file(modpath, path=None):
+    """get a module type / file path
+
+    :type modpath: list or tuple
+    :param modpath:
+      splitted module's name (i.e name of a module or package splitted
+      on '.'), with leading empty strings for explicit relative import
+
+    :type path: list or None
+    :param path:
+      optional list of path where the module or package should be
+      searched (use sys.path if nothing or None is given)
+
+
+    :rtype: tuple(int, str)
+    :return: the module type flag and the file path for a module
+    """
+    # egg support compat
+    try:
+        pic = sys.path_importer_cache
+        _path = (path is None and sys.path or path)
+        for __path in _path:
+            if not __path in pic:
+                try:
+                    pic[__path] = zipimport.zipimporter(__path)
+                except zipimport.ZipImportError:
+                    pic[__path] = None
+        checkeggs = True
+    except AttributeError:
+        checkeggs = False
+    imported = []
+    while modpath:
+        try:
+            _, mp_filename, mp_desc = find_module(modpath[0], path)
+        except ImportError:
+            if checkeggs:
+                return _search_zip(modpath, pic)[:2]
+            raise
+        else:
+            if checkeggs:
+                fullabspath = [abspath(x) for x in _path]
+                try:
+                    pathindex = fullabspath.index(dirname(abspath(mp_filename)))
+                    emtype, emp_filename, zippath = _search_zip(modpath, pic)
+                    if pathindex > _path.index(zippath):
+                        # an egg takes priority
+                        return emtype, emp_filename
+                except ValueError:
+                    # XXX not in _path
+                    pass
+                except ImportError:
+                    pass
+                checkeggs = False
+        imported.append(modpath.pop(0))
+        mtype = mp_desc[2]
+        if modpath:
+            if mtype != PKG_DIRECTORY:
+                raise ImportError('No module %s in %s' % ('.'.join(modpath),
+                                                          '.'.join(imported)))
+            path = [mp_filename]
+    return mtype, mp_filename
+
+def _is_python_file(filename):
+    """return true if the given filename should be considered as a python file
+
+    .pyc and .pyo are ignored
+    """
+    for ext in ('.py', '.so', '.pyd', '.pyw'):
+        if filename.endswith(ext):
+            return True
+    return False
+
+
+def _has_init(directory):
+    """if the given directory has a valid __init__ file, return its path,
+    else return None
+    """
+    mod_or_pack = join(directory, '__init__')
+    for ext in PY_SOURCE_EXTS + ('pyc', 'pyo'):
+        if exists(mod_or_pack + '.' + ext):
+            return mod_or_pack + '.' + ext
+    return None