Use Pathlib here and there.

This make code a little bit more compact and readable.

IPython/core/application.py

@@ -1,462 +1,464 b''
 # encoding: utf-8
 """
 An application for IPython.
 
 All top-level applications should use the classes in this module for
 handling configuration and creating configurables.
 
 The job of an :class:`Application` is to create the master configuration
 object and then create the configurable objects, passing the config to them.
 """
 
 # Copyright (c) IPython Development Team.
 # Distributed under the terms of the Modified BSD License.
 
 import atexit
 from copy import deepcopy
 import glob
 import logging
 import os
 import shutil
 import sys
 
+from pathlib import Path
+
 from traitlets.config.application import Application, catch_config_error
 from traitlets.config.loader import ConfigFileNotFound, PyFileConfigLoader
 from IPython.core import release, crashhandler
 from IPython.core.profiledir import ProfileDir, ProfileDirError
 from IPython.paths import get_ipython_dir, get_ipython_package_dir
 from IPython.utils.path import ensure_dir_exists
 from traitlets import (
     List, Unicode, Type, Bool, Set, Instance, Undefined,
     default, observe,
 )
 
-if os.name == 'nt':
-    programdata = os.environ.get('PROGRAMDATA', None)
+if os.name == "nt":
+    programdata = Path(os.environ.get("PROGRAMDATA", None))
     if programdata:
-        SYSTEM_CONFIG_DIRS = [os.path.join(programdata, 'ipython')]
+        SYSTEM_CONFIG_DIRS = [programdata / "ipython"]
     else:  # PROGRAMDATA is not defined by default on XP.
         SYSTEM_CONFIG_DIRS = []
 else:
     SYSTEM_CONFIG_DIRS = [
         "/usr/local/etc/ipython",
         "/etc/ipython",
     ]
 
 
 ENV_CONFIG_DIRS = []
 _env_config_dir = os.path.join(sys.prefix, 'etc', 'ipython')
 if _env_config_dir not in SYSTEM_CONFIG_DIRS:
     # only add ENV_CONFIG if sys.prefix is not already included
     ENV_CONFIG_DIRS.append(_env_config_dir)
 
 
 _envvar = os.environ.get('IPYTHON_SUPPRESS_CONFIG_ERRORS')
 if _envvar in {None, ''}:
     IPYTHON_SUPPRESS_CONFIG_ERRORS = None
 else:
     if _envvar.lower() in {'1','true'}:
         IPYTHON_SUPPRESS_CONFIG_ERRORS = True
     elif _envvar.lower() in {'0','false'} :
         IPYTHON_SUPPRESS_CONFIG_ERRORS = False
     else:
         sys.exit("Unsupported value for environment variable: 'IPYTHON_SUPPRESS_CONFIG_ERRORS' is set to '%s' which is none of  {'0', '1', 'false', 'true', ''}."% _envvar )
 
 # aliases and flags
 
 base_aliases = {
     'profile-dir' : 'ProfileDir.location',
     'profile' : 'BaseIPythonApplication.profile',
     'ipython-dir' : 'BaseIPythonApplication.ipython_dir',
     'log-level' : 'Application.log_level',
     'config' : 'BaseIPythonApplication.extra_config_file',
 }
 
 base_flags = dict(
     debug = ({'Application' : {'log_level' : logging.DEBUG}},
             "set log level to logging.DEBUG (maximize logging output)"),
     quiet = ({'Application' : {'log_level' : logging.CRITICAL}},
             "set log level to logging.CRITICAL (minimize logging output)"),
     init = ({'BaseIPythonApplication' : {
                     'copy_config_files' : True,
                     'auto_create' : True}
             }, """Initialize profile with default config files.  This is equivalent
             to running `ipython profile create <profile>` prior to startup.
             """)
 )
 
 class ProfileAwareConfigLoader(PyFileConfigLoader):
     """A Python file config loader that is aware of IPython profiles."""
     def load_subconfig(self, fname, path=None, profile=None):
         if profile is not None:
             try:
                 profile_dir = ProfileDir.find_profile_dir_by_name(
                         get_ipython_dir(),
                         profile,
                 )
             except ProfileDirError:
                 return
             path = profile_dir.location
         return super(ProfileAwareConfigLoader, self).load_subconfig(fname, path=path)
 
 class BaseIPythonApplication(Application):
 
     name = u'ipython'
     description = Unicode(u'IPython: an enhanced interactive Python shell.')
     version = Unicode(release.version)
 
     aliases = base_aliases
     flags = base_flags
     classes = List([ProfileDir])
     
     # enable `load_subconfig('cfg.py', profile='name')`
     python_config_loader_class = ProfileAwareConfigLoader
 
     # Track whether the config_file has changed,
     # because some logic happens only if we aren't using the default.
     config_file_specified = Set()
 
     config_file_name = Unicode()
     @default('config_file_name')
     def _config_file_name_default(self):
         return self.name.replace('-','_') + u'_config.py'
     @observe('config_file_name')
     def _config_file_name_changed(self, change):
         if change['new'] != change['old']:
             self.config_file_specified.add(change['new'])
 
     # The directory that contains IPython's builtin profiles.
     builtin_profile_dir = Unicode(
         os.path.join(get_ipython_package_dir(), u'config', u'profile', u'default')
     )
     
     config_file_paths = List(Unicode())
     @default('config_file_paths')
     def _config_file_paths_default(self):
         return [os.getcwd()]
 
     extra_config_file = Unicode(
     help="""Path to an extra config file to load.
     
     If specified, load this config file in addition to any other IPython config.
     """).tag(config=True)
     @observe('extra_config_file')
     def _extra_config_file_changed(self, change):
         old = change['old']
         new = change['new']
         try:
             self.config_files.remove(old)
         except ValueError:
             pass
         self.config_file_specified.add(new)
         self.config_files.append(new)
 
     profile = Unicode(u'default',
         help="""The IPython profile to use."""
     ).tag(config=True)
     
     @observe('profile')
     def _profile_changed(self, change):
         self.builtin_profile_dir = os.path.join(
                 get_ipython_package_dir(), u'config', u'profile', change['new']
         )
 
     ipython_dir = Unicode(
         help="""
         The name of the IPython directory. This directory is used for logging
         configuration (through profiles), history storage, etc. The default
         is usually $HOME/.ipython. This option can also be specified through
         the environment variable IPYTHONDIR.
         """
     ).tag(config=True)
     @default('ipython_dir')
     def _ipython_dir_default(self):
         d = get_ipython_dir()
         self._ipython_dir_changed({
             'name': 'ipython_dir',
             'old': d,
             'new': d,
         })
         return d
     
     _in_init_profile_dir = False
     profile_dir = Instance(ProfileDir, allow_none=True)
     @default('profile_dir')
     def _profile_dir_default(self):
         # avoid recursion
         if self._in_init_profile_dir:
             return
         # profile_dir requested early, force initialization
         self.init_profile_dir()
         return self.profile_dir
 
     overwrite = Bool(False,
         help="""Whether to overwrite existing config files when copying"""
     ).tag(config=True)
     auto_create = Bool(False,
         help="""Whether to create profile dir if it doesn't exist"""
     ).tag(config=True)
 
     config_files = List(Unicode())
     @default('config_files')
     def _config_files_default(self):
         return [self.config_file_name]
 
     copy_config_files = Bool(False,
         help="""Whether to install the default config files into the profile dir.
         If a new profile is being created, and IPython contains config files for that
         profile, then they will be staged into the new directory.  Otherwise,
         default config files will be automatically generated.
         """).tag(config=True)
     
     verbose_crash = Bool(False,
         help="""Create a massive crash report when IPython encounters what may be an
         internal error.  The default is to append a short message to the
         usual traceback""").tag(config=True)
 
     # The class to use as the crash handler.
     crash_handler_class = Type(crashhandler.CrashHandler)
 
     @catch_config_error
     def __init__(self, **kwargs):
         super(BaseIPythonApplication, self).__init__(**kwargs)
         # ensure current working directory exists
         try:
             os.getcwd()
         except:
             # exit if cwd doesn't exist
             self.log.error("Current working directory doesn't exist.")
             self.exit(1)
 
     #-------------------------------------------------------------------------
     # Various stages of Application creation
     #-------------------------------------------------------------------------
     
     deprecated_subcommands = {}
     
     def initialize_subcommand(self, subc, argv=None):
         if subc in self.deprecated_subcommands:
             self.log.warning("Subcommand `ipython {sub}` is deprecated and will be removed "
                              "in future versions.".format(sub=subc))
             self.log.warning("You likely want to use `jupyter {sub}` in the "
                              "future".format(sub=subc))
         return super(BaseIPythonApplication, self).initialize_subcommand(subc, argv)
 
     def init_crash_handler(self):
         """Create a crash handler, typically setting sys.excepthook to it."""
         self.crash_handler = self.crash_handler_class(self)
         sys.excepthook = self.excepthook
         def unset_crashhandler():
             sys.excepthook = sys.__excepthook__
         atexit.register(unset_crashhandler)
     
     def excepthook(self, etype, evalue, tb):
         """this is sys.excepthook after init_crashhandler
         
         set self.verbose_crash=True to use our full crashhandler, instead of
         a regular traceback with a short message (crash_handler_lite)
         """
         
         if self.verbose_crash:
             return self.crash_handler(etype, evalue, tb)
         else:
             return crashhandler.crash_handler_lite(etype, evalue, tb)
 
     @observe('ipython_dir')
     def _ipython_dir_changed(self, change):
         old = change['old']
         new = change['new']
         if old is not Undefined:
             str_old = os.path.abspath(old)
             if str_old in sys.path:
                 sys.path.remove(str_old)
         str_path = os.path.abspath(new)
         sys.path.append(str_path)
         ensure_dir_exists(new)
         readme = os.path.join(new, 'README')
         readme_src = os.path.join(get_ipython_package_dir(), u'config', u'profile', 'README')
         if not os.path.exists(readme) and os.path.exists(readme_src):
             shutil.copy(readme_src, readme)
         for d in ('extensions', 'nbextensions'):
             path = os.path.join(new, d)
             try:
                 ensure_dir_exists(path)
             except OSError as e:
                 # this will not be EEXIST
                 self.log.error("couldn't create path %s: %s", path, e)
         self.log.debug("IPYTHONDIR set to: %s" % new)
 
     def load_config_file(self, suppress_errors=IPYTHON_SUPPRESS_CONFIG_ERRORS):
         """Load the config file.
 
         By default, errors in loading config are handled, and a warning
         printed on screen. For testing, the suppress_errors option is set
         to False, so errors will make tests fail.
 
         `suppress_errors` default value is to be `None` in which case the
         behavior default to the one of `traitlets.Application`.
 
         The default value can be set :
            - to `False` by setting 'IPYTHON_SUPPRESS_CONFIG_ERRORS' environment variable to '0', or 'false' (case insensitive).
            - to `True` by setting 'IPYTHON_SUPPRESS_CONFIG_ERRORS' environment variable to '1' or 'true' (case insensitive).
            - to `None` by setting 'IPYTHON_SUPPRESS_CONFIG_ERRORS' environment variable to '' (empty string) or leaving it unset.
 
         Any other value are invalid, and will make IPython exit with a non-zero return code.
         """
 
 
         self.log.debug("Searching path %s for config files", self.config_file_paths)
         base_config = 'ipython_config.py'
         self.log.debug("Attempting to load config file: %s" %
                        base_config)
         try:
             if suppress_errors is not None:
                 old_value = Application.raise_config_file_errors
                 Application.raise_config_file_errors = not suppress_errors;
             Application.load_config_file(
                 self,
                 base_config,
                 path=self.config_file_paths
             )
         except ConfigFileNotFound:
             # ignore errors loading parent
             self.log.debug("Config file %s not found", base_config)
             pass
         if suppress_errors is not None:
             Application.raise_config_file_errors = old_value
         
         for config_file_name in self.config_files:
             if not config_file_name or config_file_name == base_config:
                 continue
             self.log.debug("Attempting to load config file: %s" %
                            self.config_file_name)
             try:
                 Application.load_config_file(
                     self,
                     config_file_name,
                     path=self.config_file_paths
                 )
             except ConfigFileNotFound:
                 # Only warn if the default config file was NOT being used.
                 if config_file_name in self.config_file_specified:
                     msg = self.log.warning
                 else:
                     msg = self.log.debug
                 msg("Config file not found, skipping: %s", config_file_name)
             except Exception:
                 # For testing purposes.
                 if not suppress_errors:
                     raise
                 self.log.warning("Error loading config file: %s" %
                               self.config_file_name, exc_info=True)
 
     def init_profile_dir(self):
         """initialize the profile dir"""
         self._in_init_profile_dir = True
         if self.profile_dir is not None:
             # already ran
             return
         if 'ProfileDir.location' not in self.config:
             # location not specified, find by profile name
             try:
                 p = ProfileDir.find_profile_dir_by_name(self.ipython_dir, self.profile, self.config)
             except ProfileDirError:
                 # not found, maybe create it (always create default profile)
                 if self.auto_create or self.profile == 'default':
                     try:
                         p = ProfileDir.create_profile_dir_by_name(self.ipython_dir, self.profile, self.config)
                     except ProfileDirError:
                         self.log.fatal("Could not create profile: %r"%self.profile)
                         self.exit(1)
                     else:
                         self.log.info("Created profile dir: %r"%p.location)
                 else:
                     self.log.fatal("Profile %r not found."%self.profile)
                     self.exit(1)
             else:
                 self.log.debug("Using existing profile dir: %r"%p.location)
         else:
             location = self.config.ProfileDir.location
             # location is fully specified
             try:
                 p = ProfileDir.find_profile_dir(location, self.config)
             except ProfileDirError:
                 # not found, maybe create it
                 if self.auto_create:
                     try:
                         p = ProfileDir.create_profile_dir(location, self.config)
                     except ProfileDirError:
                         self.log.fatal("Could not create profile directory: %r"%location)
                         self.exit(1)
                     else:
                         self.log.debug("Creating new profile dir: %r"%location)
                 else:
                     self.log.fatal("Profile directory %r not found."%location)
                     self.exit(1)
             else:
                 self.log.info("Using existing profile dir: %r"%location)
             # if profile_dir is specified explicitly, set profile name
             dir_name = os.path.basename(p.location)
             if dir_name.startswith('profile_'):
                 self.profile = dir_name[8:]
 
         self.profile_dir = p
         self.config_file_paths.append(p.location)
         self._in_init_profile_dir = False
 
     def init_config_files(self):
         """[optionally] copy default config files into profile dir."""
         self.config_file_paths.extend(ENV_CONFIG_DIRS)
         self.config_file_paths.extend(SYSTEM_CONFIG_DIRS)
         # copy config files
-        path = self.builtin_profile_dir
+        path = Path(self.builtin_profile_dir)
         if self.copy_config_files:
             src = self.profile
 
             cfg = self.config_file_name
-            if path and os.path.exists(os.path.join(path, cfg)):
-                self.log.warning("Staging %r from %s into %r [overwrite=%s]"%(
-                        cfg, src, self.profile_dir.location, self.overwrite)
+            if path and (path / cfg).exists():
+                self.log.warning(
+                    "Staging %r from %s into %r [overwrite=%s]"
+                    % (cfg, src, self.profile_dir.location, self.overwrite)
                 )
                 self.profile_dir.copy_config_file(cfg, path=path, overwrite=self.overwrite)
             else:
                 self.stage_default_config_file()
         else:
             # Still stage *bundled* config files, but not generated ones
             # This is necessary for `ipython profile=sympy` to load the profile
             # on the first go
-            files = glob.glob(os.path.join(path, '*.py'))
+            files = path.glob("*.py")
             for fullpath in files:
-                cfg = os.path.basename(fullpath)
+                cfg = fullpath.name
                 if self.profile_dir.copy_config_file(cfg, path=path, overwrite=False):
                     # file was copied
                     self.log.warning("Staging bundled %s from %s into %r"%(
                             cfg, self.profile, self.profile_dir.location)
                     )
 
 
     def stage_default_config_file(self):
         """auto generate default config file, and stage it into the profile."""
         s = self.generate_config_file()
-        fname = os.path.join(self.profile_dir.location, self.config_file_name)
-        if self.overwrite or not os.path.exists(fname):
-            self.log.warning("Generating default config file: %r"%(fname))
-            with open(fname, 'w') as f:
-                f.write(s)
+        config_file = Path(self.profile_dir.location) / self.config_file_name
+        if self.overwrite or not config_file.exists():
+            self.log.warning("Generating default config file: %r" % (config_file))
+            config_file.write_text(s)
 
     @catch_config_error
     def initialize(self, argv=None):
         # don't hook up crash handler before parsing command-line
         self.parse_command_line(argv)
         self.init_crash_handler()
         if self.subapp is not None:
             # stop here if subapp is taking over
             return
         # save a copy of CLI config to re-load after config files
         # so that it has highest priority
         cl_config = deepcopy(self.config)
         self.init_profile_dir()
         self.init_config_files()
         self.load_config_file()
         # enforce cl-opts override configfile opts:
         self.update_config(cl_config)

IPython/core/profiledir.py

@@ -1,223 +1,225 b''
 # encoding: utf-8
 """An object for managing IPython profile directories."""
 
 # Copyright (c) IPython Development Team.
 # Distributed under the terms of the Modified BSD License.
 
 import os
 import shutil
 import errno
+from pathlib import Path
 
 from traitlets.config.configurable import LoggingConfigurable
 from ..paths import get_ipython_package_dir
 from ..utils.path import expand_path, ensure_dir_exists
 from traitlets import Unicode, Bool, observe
 
 #-----------------------------------------------------------------------------
 # Module errors
 #-----------------------------------------------------------------------------
 
 class ProfileDirError(Exception):
     pass
 
 
 #-----------------------------------------------------------------------------
 # Class for managing profile directories
 #-----------------------------------------------------------------------------
 
 class ProfileDir(LoggingConfigurable):
     """An object to manage the profile directory and its resources.
 
     The profile directory is used by all IPython applications, to manage
     configuration, logging and security.
 
     This object knows how to find, create and manage these directories. This
     should be used by any code that wants to handle profiles.
     """
 
     security_dir_name = Unicode('security')
     log_dir_name = Unicode('log')
     startup_dir_name = Unicode('startup')
     pid_dir_name = Unicode('pid')
     static_dir_name = Unicode('static')
     security_dir = Unicode(u'')
     log_dir = Unicode(u'')
     startup_dir = Unicode(u'')
     pid_dir = Unicode(u'')
     static_dir = Unicode(u'')
 
     location = Unicode(u'',
         help="""Set the profile location directly. This overrides the logic used by the
         `profile` option.""",
         ).tag(config=True)
 
     _location_isset = Bool(False) # flag for detecting multiply set location
     @observe('location')
     def _location_changed(self, change):
         if self._location_isset:
             raise RuntimeError("Cannot set profile location more than once.")
         self._location_isset = True
         new = change['new']
         ensure_dir_exists(new)
 
         # ensure config files exist:
         self.security_dir = os.path.join(new, self.security_dir_name)
         self.log_dir = os.path.join(new, self.log_dir_name)
         self.startup_dir = os.path.join(new, self.startup_dir_name)
         self.pid_dir = os.path.join(new, self.pid_dir_name)
         self.static_dir = os.path.join(new, self.static_dir_name)
         self.check_dirs()
     
     def _mkdir(self, path, mode=None):
         """ensure a directory exists at a given path
 
         This is a version of os.mkdir, with the following differences:
 
         - returns True if it created the directory, False otherwise
         - ignores EEXIST, protecting against race conditions where
           the dir may have been created in between the check and
           the creation
         - sets permissions if requested and the dir already exists
         """
         if os.path.exists(path):
             if mode and os.stat(path).st_mode != mode:
                 try:
                     os.chmod(path, mode)
                 except OSError:
                     self.log.warning(
                         "Could not set permissions on %s",
                         path
                     )
             return False
         try:
             if mode:
                 os.mkdir(path, mode)
             else:
                 os.mkdir(path)
         except OSError as e:
             if e.errno == errno.EEXIST:
                 return False
             else:
                 raise
 
         return True
     
     @observe('log_dir')
     def check_log_dir(self, change=None):
         self._mkdir(self.log_dir)
     
     @observe('startup_dir')
     def check_startup_dir(self, change=None):
         self._mkdir(self.startup_dir)
 
         readme = os.path.join(self.startup_dir, 'README')
         src = os.path.join(get_ipython_package_dir(), u'core', u'profile', u'README_STARTUP')
 
         if not os.path.exists(src):
             self.log.warning("Could not copy README_STARTUP to startup dir. Source file %s does not exist.", src)
 
         if os.path.exists(src) and not os.path.exists(readme):
             shutil.copy(src, readme)
 
     @observe('security_dir')
     def check_security_dir(self, change=None):
         self._mkdir(self.security_dir, 0o40700)
 
     @observe('pid_dir')
     def check_pid_dir(self, change=None):
         self._mkdir(self.pid_dir, 0o40700)
 
     def check_dirs(self):
         self.check_security_dir()
         self.check_log_dir()
         self.check_pid_dir()
         self.check_startup_dir()
 
-    def copy_config_file(self, config_file, path=None, overwrite=False):
+    def copy_config_file(self, config_file: str, path: Path, overwrite=False) -> bool:
         """Copy a default config file into the active profile directory.
 
         Default configuration files are kept in :mod:`IPython.core.profile`.
         This function moves these from that location to the working profile
         directory.
         """
-        dst = os.path.join(self.location, config_file)
-        if os.path.isfile(dst) and not overwrite:
+        dst = Path(os.path.join(self.location, config_file))
+        if dst.exists() and not overwrite:
             return False
         if path is None:
             path = os.path.join(get_ipython_package_dir(), u'core', u'profile', u'default')
-        src = os.path.join(path, config_file)
+        assert isinstance(path, Path)
+        src = path / config_file
         shutil.copy(src, dst)
         return True
 
     @classmethod
     def create_profile_dir(cls, profile_dir, config=None):
         """Create a new profile directory given a full path.
 
         Parameters
         ----------
         profile_dir : str
             The full path to the profile directory.  If it does exist, it will
             be used.  If not, it will be created.
         """
         return cls(location=profile_dir, config=config)
 
     @classmethod
     def create_profile_dir_by_name(cls, path, name=u'default', config=None):
         """Create a profile dir by profile name and path.
 
         Parameters
         ----------
         path : unicode
             The path (directory) to put the profile directory in.
         name : unicode
             The name of the profile.  The name of the profile directory will
             be "profile_<profile>".
         """
         if not os.path.isdir(path):
             raise ProfileDirError('Directory not found: %s' % path)
         profile_dir = os.path.join(path, u'profile_' + name)
         return cls(location=profile_dir, config=config)
 
     @classmethod
     def find_profile_dir_by_name(cls, ipython_dir, name=u'default', config=None):
         """Find an existing profile dir by profile name, return its ProfileDir.
 
         This searches through a sequence of paths for a profile dir.  If it
         is not found, a :class:`ProfileDirError` exception will be raised.
 
         The search path algorithm is:
         1. ``os.getcwd()``
         2. ``ipython_dir``
 
         Parameters
         ----------
         ipython_dir : unicode or str
             The IPython directory to use.
         name : unicode or str
             The name of the profile.  The name of the profile directory
             will be "profile_<profile>".
         """
         dirname = u'profile_' + name
         paths = [os.getcwd(), ipython_dir]
         for p in paths:
             profile_dir = os.path.join(p, dirname)
             if os.path.isdir(profile_dir):
                 return cls(location=profile_dir, config=config)
         else:
             raise ProfileDirError('Profile directory not found in paths: %s' % dirname)
 
     @classmethod
     def find_profile_dir(cls, profile_dir, config=None):
         """Find/create a profile dir and return its ProfileDir.
 
         This will create the profile directory if it doesn't exist.
 
         Parameters
         ----------
         profile_dir : unicode or str
             The path of the profile directory.
         """
         profile_dir = expand_path(profile_dir)
         if not os.path.isdir(profile_dir):
             raise ProfileDirError('Profile directory not found: %s' % profile_dir)
         return cls(location=profile_dir, config=config)