Merge: #14645: Generator now emits correct linesep for all parts.

Previously the parts of the message retained whatever linesep they had on
read, which means if the messages weren't read in univeral newline mode, the
line endings could well be inconsistent.  In general sending it via smtplib
would result in them getting fixed, but it is better to generate them
correctly to begin with.  Also, the new send_message method of smtplib does
not do the fixup, so that method is producing rfc-invalid output without this
fix.

1 files changed, 407 insertions, 0 deletions

diff --git a/Lib/venv/__init__.py b/Lib/venv/__init__.py
new file mode 100644
index 0000000000..3920747931
--- /dev/null
+++ b/Lib/venv/__init__.py
@@ -0,0 +1,407 @@
+"""
+Virtual environment (venv) package for Python. Based on PEP 405.
+
+Copyright (C) 2011-2012 Vinay Sajip.
+Licensed to the PSF under a contributor agreement.
+
+usage: python -m venv [-h] [--system-site-packages] [--symlinks] [--clear]
+            [--upgrade]
+            ENV_DIR [ENV_DIR ...]
+
+Creates virtual Python environments in one or more target directories.
+
+positional arguments:
+  ENV_DIR               A directory to create the environment in.
+
+optional arguments:
+  -h, --help            show this help message and exit
+  --system-site-packages
+                        Give the virtual environment access to the system
+                        site-packages dir.
+  --symlinks            Attempt to symlink rather than copy.
+  --clear               Delete the environment directory if it already exists.
+                        If not specified and the directory exists, an error is
+                        raised.
+  --upgrade             Upgrade the environment directory to use this version
+                        of Python, assuming Python has been upgraded in-place.
+"""
+import base64
+import io
+import logging
+import os
+import os.path
+import shutil
+import sys
+import sysconfig
+try:
+    import threading
+except ImportError:
+    threading = None
+
+logger = logging.getLogger(__name__)
+
+class Context:
+    """
+    Holds information about a current venv creation/upgrade request.
+    """
+    pass
+
+
+class EnvBuilder:
+    """
+    This class exists to allow virtual environment creation to be
+    customised. The constructor parameters determine the builder's
+    behaviour when called upon to create a virtual environment.
+
+    By default, the builder makes the system (global) site-packages dir
+    *un*available to the created environment.
+
+    If invoked using the Python -m option, the default is to use copying
+    on Windows platforms but symlinks elsewhere. If instantiated some
+    other way, the default is to *not* use symlinks.
+
+    :param system_site_packages: If True, the system (global) site-packages
+                                 dir is available to created environments.
+    :param clear: If True and the target directory exists, it is deleted.
+                  Otherwise, if the target directory exists, an error is
+                  raised.
+    :param symlinks: If True, attempt to symlink rather than copy files into
+                     virtual environment.
+    :param upgrade: If True, upgrade an existing virtual environment.
+    """
+
+    def __init__(self, system_site_packages=False, clear=False,
+                 symlinks=False, upgrade=False):
+        self.system_site_packages = system_site_packages
+        self.clear = clear
+        self.symlinks = symlinks
+        self.upgrade = upgrade
+
+    def create(self, env_dir):
+        """
+        Create a virtual environment in a directory.
+
+        :param env_dir: The target directory to create an environment in.
+
+        """
+        env_dir = os.path.abspath(env_dir)
+        context = self.ensure_directories(env_dir)
+        self.create_configuration(context)
+        self.setup_python(context)
+        if not self.upgrade:
+            self.setup_scripts(context)
+            self.post_setup(context)
+
+    def ensure_directories(self, env_dir):
+        """
+        Create the directories for the environment.
+
+        Returns a context object which holds paths in the environment,
+        for use by subsequent logic.
+        """
+
+        def create_if_needed(d):
+            if not os.path.exists(d):
+                os.makedirs(d)
+
+        if os.path.exists(env_dir) and not (self.clear or self.upgrade):
+            raise ValueError('Directory exists: %s' % env_dir)
+        if os.path.exists(env_dir) and self.clear:
+            shutil.rmtree(env_dir)
+        context = Context()
+        context.env_dir = env_dir
+        context.env_name = os.path.split(env_dir)[1]
+        context.prompt = '(%s) ' % context.env_name
+        create_if_needed(env_dir)
+        env = os.environ
+        if sys.platform == 'darwin' and '__PYVENV_LAUNCHER__' in env:
+            executable = os.environ['__PYVENV_LAUNCHER__']
+        else:
+            executable = sys.executable
+        dirname, exename = os.path.split(os.path.abspath(executable))
+        context.executable = executable
+        context.python_dir = dirname
+        context.python_exe = exename
+        if sys.platform == 'win32':
+            binname = 'Scripts'
+            incpath = 'Include'
+            libpath = os.path.join(env_dir, 'Lib', 'site-packages')
+        else:
+            binname = 'bin'
+            incpath = 'include'
+            libpath = os.path.join(env_dir, 'lib', 'python%d.%d' % sys.version_info[:2], 'site-packages')
+        context.inc_path = path = os.path.join(env_dir, incpath)
+        create_if_needed(path)
+        create_if_needed(libpath)
+        context.bin_path = binpath = os.path.join(env_dir, binname)
+        context.bin_name = binname
+        context.env_exe = os.path.join(binpath, exename)
+        create_if_needed(binpath)
+        return context
+
+    def create_configuration(self, context):
+        """
+        Create a configuration file indicating where the environment's Python
+        was copied from, and whether the system site-packages should be made
+        available in the environment.
+
+        :param context: The information for the environment creation request
+                        being processed.
+        """
+        context.cfg_path = path = os.path.join(context.env_dir, 'pyvenv.cfg')
+        with open(path, 'w', encoding='utf-8') as f:
+            f.write('home = %s\n' % context.python_dir)
+            if self.system_site_packages:
+                incl = 'true'
+            else:
+                incl = 'false'
+            f.write('include-system-site-packages = %s\n' % incl)
+            f.write('version = %d.%d.%d\n' % sys.version_info[:3])
+
+    if os.name == 'nt':
+        def include_binary(self, f):
+            if f.endswith(('.pyd', '.dll')):
+                result = True
+            else:
+                result = f.startswith('python') and f.endswith('.exe')
+            return result
+
+    def symlink_or_copy(self, src, dst):
+        """
+        Try symlinking a file, and if that fails, fall back to copying.
+        """
+        force_copy = not self.symlinks
+        if not force_copy:
+            try:
+                if not os.path.islink(dst): # can't link to itself!
+                    os.symlink(src, dst)
+            except Exception:   # may need to use a more specific exception
+                logger.warning('Unable to symlink %r to %r', src, dst)
+                force_copy = True
+        if force_copy:
+            shutil.copyfile(src, dst)
+
+    def setup_python(self, context):
+        """
+        Set up a Python executable in the environment.
+
+        :param context: The information for the environment creation request
+                        being processed.
+        """
+        binpath = context.bin_path
+        exename = context.python_exe
+        path = context.env_exe
+        copier = self.symlink_or_copy
+        copier(context.executable, path)
+        dirname = context.python_dir
+        if os.name != 'nt':
+            if not os.path.islink(path):
+                os.chmod(path, 0o755)
+            for suffix in ('python', 'python3'):
+                path = os.path.join(binpath, suffix)
+                if not os.path.exists(path):
+                    os.symlink(exename, path)
+        else:
+            subdir = 'DLLs'
+            include = self.include_binary
+            files = [f for f in os.listdir(dirname) if include(f)]
+            for f in files:
+                src = os.path.join(dirname, f)
+                dst = os.path.join(binpath, f)
+                if dst != context.env_exe:  # already done, above
+                    copier(src, dst)
+            dirname = os.path.join(dirname, subdir)
+            if os.path.isdir(dirname):
+                files = [f for f in os.listdir(dirname) if include(f)]
+                for f in files:
+                    src = os.path.join(dirname, f)
+                    dst = os.path.join(binpath, f)
+                    copier(src, dst)
+            # copy init.tcl over
+            for root, dirs, files in os.walk(context.python_dir):
+                if 'init.tcl' in files:
+                    tcldir = os.path.basename(root)
+                    tcldir = os.path.join(context.env_dir, 'Lib', tcldir)
+                    os.makedirs(tcldir)
+                    src = os.path.join(root, 'init.tcl')
+                    dst = os.path.join(tcldir, 'init.tcl')
+                    shutil.copyfile(src, dst)
+                    break
+
+    def setup_scripts(self, context):
+        """
+        Set up scripts into the created environment from a directory.
+
+        This method installs the default scripts into the environment
+        being created. You can prevent the default installation by overriding
+        this method if you really need to, or if you need to specify
+        a different location for the scripts to install. By default, the
+        'scripts' directory in the venv package is used as the source of
+        scripts to install.
+        """
+        path = os.path.abspath(os.path.dirname(__file__))
+        path = os.path.join(path, 'scripts')
+        self.install_scripts(context, path)
+
+    def post_setup(self, context):
+        """
+        Hook for post-setup modification of the venv. Subclasses may install
+        additional packages or scripts here, add activation shell scripts, etc.
+
+        :param context: The information for the environment creation request
+                        being processed.
+        """
+        pass
+
+    def replace_variables(self, text, context):
+        """
+        Replace variable placeholders in script text with context-specific
+        variables.
+
+        Return the text passed in , but with variables replaced.
+
+        :param text: The text in which to replace placeholder variables.
+        :param context: The information for the environment creation request
+                        being processed.
+        """
+        text = text.replace('__VENV_DIR__', context.env_dir)
+        text = text.replace('__VENV_NAME__', context.prompt)
+        text = text.replace('__VENV_BIN_NAME__', context.bin_name)
+        text = text.replace('__VENV_PYTHON__', context.env_exe)
+        return text
+
+    def install_scripts(self, context, path):
+        """
+        Install scripts into the created environment from a directory.
+
+        :param context: The information for the environment creation request
+                        being processed.
+        :param path:    Absolute pathname of a directory containing script.
+                        Scripts in the 'common' subdirectory of this directory,
+                        and those in the directory named for the platform
+                        being run on, are installed in the created environment.
+                        Placeholder variables are replaced with environment-
+                        specific values.
+        """
+        binpath = context.bin_path
+        plen = len(path)
+        for root, dirs, files in os.walk(path):
+            if root == path: # at top-level, remove irrelevant dirs
+                for d in dirs[:]:
+                    if d not in ('common', os.name):
+                        dirs.remove(d)
+                continue # ignore files in top level
+            for f in files:
+                srcfile = os.path.join(root, f)
+                suffix = root[plen:].split(os.sep)[2:]
+                if not suffix:
+                    dstdir = binpath
+                else:
+                    dstdir = os.path.join(binpath, *suffix)
+                if not os.path.exists(dstdir):
+                    os.makedirs(dstdir)
+                dstfile = os.path.join(dstdir, f)
+                with open(srcfile, 'rb') as f:
+                    data = f.read()
+                if srcfile.endswith('.exe'):
+                    mode = 'wb'
+                else:
+                    mode = 'w'
+                    try:
+                        data = data.decode('utf-8')
+                        data = self.replace_variables(data, context)
+                    except UnicodeDecodeError as e:
+                        data = None
+                        logger.warning('unable to copy script %r, '
+                                       'may be binary: %s', srcfile, e)
+                if data is not None:
+                    with open(dstfile, mode) as f:
+                        f.write(data)
+                    shutil.copymode(srcfile, dstfile)
+
+
+def create(env_dir, system_site_packages=False, clear=False, symlinks=False):
+    """
+    Create a virtual environment in a directory.
+
+    By default, makes the system (global) site-packages dir *un*available to
+    the created environment, and uses copying rather than symlinking for files
+    obtained from the source Python installation.
+
+    :param env_dir: The target directory to create an environment in.
+    :param system_site_packages: If True, the system (global) site-packages
+                                 dir is available to the environment.
+    :param clear: If True and the target directory exists, it is deleted.
+                  Otherwise, if the target directory exists, an error is
+                  raised.
+    :param symlinks: If True, attempt to symlink rather than copy files into
+                     virtual environment.
+    """
+    builder = EnvBuilder(system_site_packages=system_site_packages,
+                                   clear=clear, symlinks=symlinks)
+    builder.create(env_dir)
+
+def main(args=None):
+    compatible = True
+    if sys.version_info < (3, 3):
+        compatible = False
+    elif not hasattr(sys, 'base_prefix'):
+        compatible = False
+    if not compatible:
+        raise ValueError('This script is only for use with Python 3.3')
+    else:
+        import argparse
+
+        parser = argparse.ArgumentParser(prog=__name__,
+                                         description='Creates virtual Python '
+                                                     'environments in one or '
+                                                     'more target '
+                                                     'directories.',
+                                         epilog='Once an environment has been '
+                                                'created, you may wish to '
+                                                'activate it, e.g. by '
+                                                'sourcing an activate script '
+                                                'in its bin directory.')
+        parser.add_argument('dirs', metavar='ENV_DIR', nargs='+',
+                            help='A directory to create the environment in.')
+        parser.add_argument('--system-site-packages', default=False,
+                            action='store_true', dest='system_site',
+                            help='Give the virtual environment access to the '
+                                 'system site-packages dir.')
+        if os.name == 'nt':
+            use_symlinks = False
+        else:
+            use_symlinks = True
+        parser.add_argument('--symlinks', default=use_symlinks,
+                            action='store_true', dest='symlinks',
+                            help='Try to use symlinks rather than copies, '
+                                 'when symlinks are not the default for '
+                                 'the platform.')
+        parser.add_argument('--clear', default=False, action='store_true',
+                            dest='clear', help='Delete the environment '
+                                               'directory if it already '
+                                               'exists. If not specified and '
+                                               'the directory exists, an error'
+                                               ' is raised.')
+        parser.add_argument('--upgrade', default=False, action='store_true',
+                            dest='upgrade', help='Upgrade the environment '
+                                               'directory to use this version '
+                                               'of Python, assuming Python '
+                                               'has been upgraded in-place.')
+        options = parser.parse_args(args)
+        if options.upgrade and options.clear:
+            raise ValueError('you cannot supply --upgrade and --clear together.')
+        builder = EnvBuilder(system_site_packages=options.system_site,
+                             clear=options.clear, symlinks=options.symlinks,
+                             upgrade=options.upgrade)
+        for d in options.dirs:
+            builder.create(d)
+
+if __name__ == '__main__':
+    rc = 1
+    try:
+        main()
+        rc = 0
+    except Exception as e:
+        print('Error: %s' % e, file=sys.stderr)
+    sys.exit(rc)