"""distutils.command.install

Implements the Distutils 'install' command."""

import sys
import sysconfig
import os
import re

from distutils import log
from distutils.core import Command
from distutils.debug import DEBUG
from distutils.sysconfig import get_config_vars, is_virtual_environment
from distutils.errors import DistutilsPlatformError
from distutils.file_util import write_file
from distutils.util import convert_path, subst_vars, change_root
from distutils.util import get_platform
from distutils.errors import DistutilsOptionError

from site import USER_BASE
from site import USER_SITE

HAS_USER_SITE = (USER_SITE is not None)

# The keys to an installation scheme; if any new types of files are to be
# installed, be sure to add an entry to every scheme in
# sysconfig._INSTALL_SCHEMES, and to SCHEME_KEYS here.
SCHEME_KEYS = ('purelib', 'platlib', 'headers', 'scripts', 'data')

# The following code provides backward-compatible INSTALL_SCHEMES
# while making the sysconfig module the single point of truth.
# This makes it easier for OS distributions where they need to
# alter locations for packages installations in a single place.
# Note that this module is deprecated (PEP 632); all consumers
# of this information should switch to using sysconfig directly.
INSTALL_SCHEMES = {"unix_prefix": {}, "unix_home": {}, "nt": {}}

# add the Debian install schemes here until they are added to sysconfig
INSTALL_SCHEMES['unix_local'] = {
    'stdlib': '{installed_base}/{platlibdir}/python{py_version_short}',
    'platstdlib': '{platbase}/{platlibdir}/python{py_version_short}',
    'purelib': '{base}/local/lib/python{py_version_short}/dist-packages',
    'platlib': '{platbase}/local/{platlibdir}/python{py_version_short}/dist-packages',
    'include': '{installed_base}/include/python{py_version_short}{abiflags}',
    'headers': '{base}/local/include/python{py_version_short}{abiflags}',
    'platinclude': '{installed_platbase}/include/python{py_version_short}{abiflags}',
    'scripts': '{base}/local/bin',
    'data': '{base}/local',
}
INSTALL_SCHEMES['deb_system'] = {
    'stdlib': '{installed_base}/{platlibdir}/python{py_version_short}',
    'platstdlib': '{platbase}/{platlibdir}/python{py_version_short}',
    'purelib': '{base}/lib/python3/dist-packages',
    'platlib': '{platbase}/{platlibdir}/python3/dist-packages',
    'include': '{installed_base}/include/python{py_version_short}{abiflags}',
    'headers': '{installed_base}/include/python{py_version_short}{abiflags}',
    'platinclude': '{installed_platbase}/include/python{py_version_short}{abiflags}',
    'scripts': '{base}/bin',
    'data': '{base}',
}

# Copy from sysconfig._INSTALL_SCHEMES
for key in SCHEME_KEYS:
    for distutils_scheme_name, sys_scheme_name in (
            ("unix_prefix", "posix_prefix"), ("unix_home", "posix_home"),
            ("nt", "nt")):
        sys_key = key
        sys_scheme = sysconfig._INSTALL_SCHEMES[sys_scheme_name]
        if key == "headers" and key not in sys_scheme:
            # On POSIX-y platforms, Python will:
            # - Build from .h files in 'headers' (only there when
            #   building CPython)
            # - Install .h files to 'include'
            # When 'headers' is missing, fall back to 'include'
            sys_key = 'include'
        INSTALL_SCHEMES[distutils_scheme_name][key] = sys_scheme[sys_key]

# Transformation to different template format
for main_key in INSTALL_SCHEMES:
    for key, value in INSTALL_SCHEMES[main_key].items():
        # Change all ocurences of {variable} to $variable
        value = re.sub(r"\{(.+?)\}", r"$\g<1>", value)
        value = value.replace("$installed_base", "$base")
        value = value.replace("$py_version_nodot_plat", "$py_version_nodot")
        if key == "headers":
            value += "/$dist_name"
        if sys.version_info >= (3, 9) and key == "platlib":
            # platlibdir is available since 3.9: bpo-1294959
            value = value.replace("/lib/", "/$platlibdir/")
        INSTALL_SCHEMES[main_key][key] = value

# The following part of INSTALL_SCHEMES has a different definition
# than the one in sysconfig, but because both depend on the site module,
# the outcomes should be the same.
if HAS_USER_SITE:
    INSTALL_SCHEMES['nt_user'] = {
        'purelib': '$usersite',
        'platlib': '$usersite',
        'headers': '$userbase/Python$py_version_nodot/Include/$dist_name',
        'scripts': '$userbase/Python$py_version_nodot/Scripts',
        'data'   : '$userbase',
        }

    INSTALL_SCHEMES['unix_user'] = {
        'purelib': '$usersite',
        'platlib': '$usersite',
        'headers':
            '$userbase/include/python$py_version_short$abiflags/$dist_name',
        'scripts': '$userbase/bin',
        'data'   : '$userbase',
        }


class install(Command):

    description = "install everything from build directory"

    user_options = [
        # Select installation scheme and set base director(y|ies)
        ('prefix=', None,
         "installation prefix"),
        ('exec-prefix=', None,
         "(Unix only) prefix for platform-specific files"),
        ('home=', None,
         "(Unix only) home directory to install under"),

        # Or, just set the base director(y|ies)
        ('install-base=', None,
         "base installation directory (instead of --prefix or --home)"),
        ('install-platbase=', None,
         "base installation directory for platform-specific files " +
         "(instead of --exec-prefix or --home)"),
        ('root=', None,
         "install everything relative to this alternate root directory"),

        # Or, explicitly set the installation scheme
        ('install-purelib=', None,
         "installation directory for pure Python module distributions"),
        ('install-platlib=', None,
         "installation directory for non-pure module distributions"),
        ('install-lib=', None,
         "installation directory for all module distributions " +
         "(overrides --install-purelib and --install-platlib)"),

        ('install-headers=', None,
         "installation directory for C/C++ headers"),
        ('install-scripts=', None,
         "installation directory for Python scripts"),
        ('install-data=', None,
         "installation directory for data files"),

        # Byte-compilation options -- see install_lib.py for details, as
        # these are duplicated from there (but only install_lib does
        # anything with them).
        ('compile', 'c', "compile .py to .pyc [default]"),
        ('no-compile', None, "don't compile .py files"),
        ('optimize=', 'O',
         "also compile with optimization: -O1 for \"python -O\", "
         "-O2 for \"python -OO\", and -O0 to disable [default: -O0]"),

        # Miscellaneous control options
        ('force', 'f',
         "force installation (overwrite any existing files)"),
        ('skip-build', None,
         "skip rebuilding everything (for testing/debugging)"),

        # Where to install documentation (eventually!)
        #('doc-format=', None, "format of documentation to generate"),
        #('install-man=', None, "directory for Unix man pages"),
        #('install-html=', None, "directory for HTML documentation"),
        #('install-info=', None, "directory for GNU info files"),

        ('record=', None,
         "filename in which to record list of installed files"),

        ('install-layout=', None,
         "installation layout to choose (known values: deb, unix)"),
        ]

    boolean_options = ['compile', 'force', 'skip-build']

    if HAS_USER_SITE:
        user_options.append(('user', None,
                             "install in user site-package '%s'" % USER_SITE))
        boolean_options.append('user')

    negative_opt = {'no-compile' : 'compile'}


    def initialize_options(self):
        """Initializes options."""
        # High-level options: these select both an installation base
        # and scheme.
        self.prefix = None
        self.exec_prefix = None
        self.home = None
        self.user = 0
        self.prefix_option = None

        # These select only the installation base; it's up to the user to
        # specify the installation scheme (currently, that means supplying
        # the --install-{platlib,purelib,scripts,data} options).
        self.install_base = None
        self.install_platbase = None
        self.root = None

        # These options are the actual installation directories; if not
        # supplied by the user, they are filled in using the installation
        # scheme implied by prefix/exec-prefix/home and the contents of
        # that installation scheme.
        self.install_purelib = None     # for pure module distributions
        self.install_platlib = None     # non-pure (dists w/ extensions)
        self.install_headers = None     # for C/C++ headers
        self.install_lib = None         # set to either purelib or platlib
        self.install_scripts = None
        self.install_data = None
        if HAS_USER_SITE:
            self.install_userbase = USER_BASE
            self.install_usersite = USER_SITE

        # enable custom installation, known values: deb
        self.install_layout = None
        self.multiarch = None

        self.compile = None
        self.optimize = None

        # Deprecated
        # These two are for putting non-packagized distributions into their
        # own directory and creating a .pth file if it makes sense.
        # 'extra_path' comes from the setup file; 'install_path_file' can
        # be turned off if it makes no sense to install a .pth file.  (But
        # better to install it uselessly than to guess wrong and not
        # install it when it's necessary and would be used!)  Currently,
        # 'install_path_file' is always true unless some outsider meddles
        # with it.
        self.extra_path = None
        self.install_path_file = 1

        # 'force' forces installation, even if target files are not
        # out-of-date.  'skip_build' skips running the "build" command,
        # handy if you know it's not necessary.  'warn_dir' (which is *not*
        # a user option, it's just there so the bdist_* commands can turn
        # it off) determines whether we warn about installing to a
        # directory not in sys.path.
        self.force = 0
        self.skip_build = 0
        self.warn_dir = 1

        # These are only here as a conduit from the 'build' command to the
        # 'install_*' commands that do the real work.  ('build_base' isn't
        # actually used anywhere, but it might be useful in future.)  They
        # are not user options, because if the user told the install
        # command where the build directory is, that wouldn't affect the
        # build command.
        self.build_base = None
        self.build_lib = None

        # Not defined yet because we don't know anything about
        # documentation yet.
        #self.install_man = None
        #self.install_html = None
        #self.install_info = None

        self.record = None


    # -- Option finalizing methods -------------------------------------
    # (This is rather more involved than for most commands,
    # because this is where the policy for installing third-
    # party Python modules on various platforms given a wide
    # array of user input is decided.  Yes, it's quite complex!)

    def finalize_options(self):
        """Finalizes options."""
        # This method (and its helpers, like 'finalize_unix()',
        # 'finalize_other()', and 'select_scheme()') is where the default
        # installation directories for modules, extension modules, and
        # anything else we care to install from a Python module
        # distribution.  Thus, this code makes a pretty important policy
        # statement about how third-party stuff is added to a Python
        # installation!  Note that the actual work of installation is done
        # by the relatively simple 'install_*' commands; they just take
        # their orders from the installation directory options determined
        # here.

        # Check for errors/inconsistencies in the options; first, stuff
        # that's wrong on any platform.

        if ((self.prefix or self.exec_prefix or self.home) and
            (self.install_base or self.install_platbase)):
            raise DistutilsOptionError(
                   "must supply either prefix/exec-prefix/home or " +
                   "install-base/install-platbase -- not both")

        if self.home and (self.prefix or self.exec_prefix):
            raise DistutilsOptionError(
                  "must supply either home or prefix/exec-prefix -- not both")

        if self.user and (self.prefix or self.exec_prefix or self.home or
                self.install_base or self.install_platbase):
            raise DistutilsOptionError("can't combine user with prefix, "
                                       "exec_prefix/home, or install_(plat)base")

        # Next, stuff that's wrong (or dubious) only on certain platforms.
        if os.name != "posix":
            if self.exec_prefix:
                self.warn("exec-prefix option ignored on this platform")
                self.exec_prefix = None

        # Now the interesting logic -- so interesting that we farm it out
        # to other methods.  The goal of these methods is to set the final
        # values for the install_{lib,scripts,data,...}  options, using as
        # input a heady brew of prefix, exec_prefix, home, install_base,
        # install_platbase, user-supplied versions of
        # install_{purelib,platlib,lib,scripts,data,...}, and the
        # INSTALL_SCHEME dictionary above.  Phew!

        self.dump_dirs("pre-finalize_{unix,other}")

        if os.name == 'posix':
            self.finalize_unix()
        else:
            self.finalize_other()

        self.dump_dirs("post-finalize_{unix,other}()")

        # Expand configuration variables, tilde, etc. in self.install_base
        # and self.install_platbase -- that way, we can use $base or
        # $platbase in the other installation directories and not worry
        # about needing recursive variable expansion (shudder).

        py_version = sys.version.split()[0]
        (prefix, exec_prefix) = get_config_vars('prefix', 'exec_prefix')
        try:
            abiflags = sys.abiflags
        except AttributeError:
            # sys.abiflags may not be defined on all platforms.
            abiflags = ''
        self.config_vars = {'dist_name': self.distribution.get_name(),
                            'dist_version': self.distribution.get_version(),
                            'dist_fullname': self.distribution.get_fullname(),
                            'py_version': py_version,
                            'py_version_short': '%d.%d' % sys.version_info[:2],
                            'py_version_nodot': '%d%d' % sys.version_info[:2],
                            'sys_prefix': prefix,
                            'prefix': prefix,
                            'sys_exec_prefix': exec_prefix,
                            'exec_prefix': exec_prefix,
                            'abiflags': abiflags,
                            'platlibdir': sys.platlibdir,
                           }

        if HAS_USER_SITE:
            self.config_vars['userbase'] = self.install_userbase
            self.config_vars['usersite'] = self.install_usersite

        if sysconfig.is_python_build(True):
            self.config_vars['srcdir'] = sysconfig.get_config_var('srcdir')

        self.expand_basedirs()

        self.dump_dirs("post-expand_basedirs()")

        # Now define config vars for the base directories so we can expand
        # everything else.
        self.config_vars['base'] = self.install_base
        self.config_vars['platbase'] = self.install_platbase

        if DEBUG:
            from pprint import pprint
            print("config vars:")
            pprint(self.config_vars)

        # Expand "~" and configuration variables in the installation
        # directories.
        self.expand_dirs()

        self.dump_dirs("post-expand_dirs()")

        # Create directories in the home dir:
        if self.user:
            self.create_home_path()

        # Pick the actual directory to install all modules to: either
        # install_purelib or install_platlib, depending on whether this
        # module distribution is pure or not.  Of course, if the user
        # already specified install_lib, use their selection.
        if self.install_lib is None:
            if self.distribution.ext_modules: # has extensions: non-pure
                self.install_lib = self.install_platlib
            else:
                self.install_lib = self.install_purelib


        # Convert directories from Unix /-separated syntax to the local
        # convention.
        self.convert_paths('lib', 'purelib', 'platlib',
                           'scripts', 'data', 'headers')
        if HAS_USER_SITE:
            self.convert_paths('userbase', 'usersite')

        # Deprecated
        # Well, we're not actually fully completely finalized yet: we still
        # have to deal with 'extra_path', which is the hack for allowing
        # non-packagized module distributions (hello, Numerical Python!) to
        # get their own directories.
        self.handle_extra_path()
        self.install_libbase = self.install_lib # needed for .pth file
        self.install_lib = os.path.join(self.install_lib, self.extra_dirs)

        # If a new root directory was supplied, make all the installation
        # dirs relative to it.
        if self.root is not None:
            self.change_roots('libbase', 'lib', 'purelib', 'platlib',
                              'scripts', 'data', 'headers')

        self.dump_dirs("after prepending root")

        # Find out the build directories, ie. where to install from.
        self.set_undefined_options('build',
                                   ('build_base', 'build_base'),
                                   ('build_lib', 'build_lib'))

        # Punt on doc directories for now -- after all, we're punting on
        # documentation completely!

    def dump_dirs(self, msg):
        """Dumps the list of user options."""
        if not DEBUG:
            return
        from distutils.fancy_getopt import longopt_xlate
        log.debug(msg + ":")
        for opt in self.user_options:
            opt_name = opt[0]
            if opt_name[-1] == "=":
                opt_name = opt_name[0:-1]
            if opt_name in self.negative_opt:
                opt_name = self.negative_opt[opt_name]
                opt_name = opt_name.translate(longopt_xlate)
                val = not getattr(self, opt_name)
            else:
                opt_name = opt_name.translate(longopt_xlate)
                val = getattr(self, opt_name)
            log.debug("  %s: %s", opt_name, val)

    def finalize_unix(self):
        """Finalizes options for posix platforms."""
        if self.install_base is not None or self.install_platbase is not None:
            if ((self.install_lib is None and
                 self.install_purelib is None and
                 self.install_platlib is None) or
                self.install_headers is None or
                self.install_scripts is None or
                self.install_data is None):
                raise DistutilsOptionError(
                      "install-base or install-platbase supplied, but "
                      "installation scheme is incomplete")
            return

        if self.user:
            if self.install_userbase is None:
                raise DistutilsPlatformError(
                    "User base directory is not specified")
            self.install_base = self.install_platbase = self.install_userbase
            self.select_scheme("unix_user")
        elif self.home is not None:
            self.install_base = self.install_platbase = self.home
            self.select_scheme("unix_home")
        else:
            self.prefix_option = self.prefix
            if self.prefix is None:
                if self.exec_prefix is not None:
                    raise DistutilsOptionError(
                          "must not supply exec-prefix without prefix")

                self.prefix = os.path.normpath(sys.prefix)
                self.exec_prefix = os.path.normpath(sys.exec_prefix)

            else:
                if self.exec_prefix is None:
                    self.exec_prefix = self.prefix

            self.install_base = self.prefix
            self.install_platbase = self.exec_prefix
            if self.install_layout:
                if self.install_layout.lower() in ['deb']:
                    import sysconfig
                    self.multiarch = sysconfig.get_config_var('MULTIARCH')
                    self.select_scheme("deb_system")
                elif self.install_layout.lower() in ['unix']:
                    self.select_scheme("unix_prefix")
                else:
                    raise DistutilsOptionError(
                        "unknown value for --install-layout")
            elif ((self.prefix_option and
                   os.path.normpath(self.prefix) != '/usr/local')
                  or is_virtual_environment()):
                self.select_scheme("unix_prefix")
            else:
                if os.path.normpath(self.prefix) == '/usr/local':
                    self.prefix = self.exec_prefix = '/usr'
                    self.install_base = self.install_platbase = '/usr'
                self.select_scheme("unix_local")

    def finalize_other(self):
        """Finalizes options for non-posix platforms"""
        if self.user:
            if self.install_userbase is None:
                raise DistutilsPlatformError(
                    "User base directory is not specified")
            self.install_base = self.install_platbase = self.install_userbase
            self.select_scheme(os.name + "_user")
        elif self.home is not None:
            self.install_base = self.install_platbase = self.home
            self.select_scheme("unix_home")
        else:
            if self.prefix is None:
                self.prefix = os.path.normpath(sys.prefix)

            self.install_base = self.install_platbase = self.prefix
            try:
                self.select_scheme(os.name)
            except KeyError:
                raise DistutilsPlatformError(
                      "I don't know how to install stuff on '%s'" % os.name)

    def select_scheme(self, name):
        """Sets the install directories by applying the install schemes."""
        # it's the caller's problem if they supply a bad name!
        scheme = INSTALL_SCHEMES[name]
        for key in SCHEME_KEYS:
            attrname = 'install_' + key
            if getattr(self, attrname) is None:
                setattr(self, attrname, scheme[key])

    def _expand_attrs(self, attrs):
        for attr in attrs:
            val = getattr(self, attr)
            if val is not None:
                if os.name == 'posix' or os.name == 'nt':
                    val = os.path.expanduser(val)
                val = subst_vars(val, self.config_vars)
                setattr(self, attr, val)

    def expand_basedirs(self):
        """Calls `os.path.expanduser` on install_base, install_platbase and
        root."""
        self._expand_attrs(['install_base', 'install_platbase', 'root'])

    def expand_dirs(self):
        """Calls `os.path.expanduser` on install dirs."""
        self._expand_attrs(['install_purelib', 'install_platlib',
                            'install_lib', 'install_headers',
                            'install_scripts', 'install_data',])

    def convert_paths(self, *names):
        """Call `convert_path` over `names`."""
        for name in names:
            attr = "install_" + name
            setattr(self, attr, convert_path(getattr(self, attr)))

    def handle_extra_path(self):
        """Set `path_file` and `extra_dirs` using `extra_path`."""
        if self.extra_path is None:
            self.extra_path = self.distribution.extra_path

        if self.extra_path is not None:
            log.warn(
                "Distribution option extra_path is deprecated. "
                "See issue27919 for details."
            )
            if isinstance(self.extra_path, str):
                self.extra_path = self.extra_path.split(',')

            if len(self.extra_path) == 1:
                path_file = extra_dirs = self.extra_path[0]
            elif len(self.extra_path) == 2:
                path_file, extra_dirs = self.extra_path
            else:
                raise DistutilsOptionError(
                      "'extra_path' option must be a list, tuple, or "
                      "comma-separated string with 1 or 2 elements")

            # convert to local form in case Unix notation used (as it
            # should be in setup scripts)
            extra_dirs = convert_path(extra_dirs)
        else:
            path_file = None
            extra_dirs = ''

        # XXX should we warn if path_file and not extra_dirs? (in which
        # case the path file would be harmless but pointless)
        self.path_file = path_file
        self.extra_dirs = extra_dirs

    def change_roots(self, *names):
        """Change the install directories pointed by name using root."""
        for name in names:
            attr = "install_" + name
            setattr(self, attr, change_root(self.root, getattr(self, attr)))

    def create_home_path(self):
        """Create directories under ~."""
        if not self.user:
            return
        home = convert_path(os.path.expanduser("~"))
        for name, path in self.config_vars.items():
            if path.startswith(home) and not os.path.isdir(path):
                self.debug_print("os.makedirs('%s', 0o700)" % path)
                os.makedirs(path, 0o700)

    # -- Command execution methods -------------------------------------

    def run(self):
        """Runs the command."""
        # Obviously have to build before we can install
        if not self.skip_build:
            self.run_command('build')
            # If we built for any other platform, we can't install.
            build_plat = self.distribution.get_command_obj('build').plat_name
            # check warn_dir - it is a clue that the 'install' is happening
            # internally, and not to sys.path, so we don't check the platform
            # matches what we are running.
            if self.warn_dir and build_plat != get_platform():
                raise DistutilsPlatformError("Can't install when "
                                             "cross-compiling")

        # Run all sub-commands (at least those that need to be run)
        for cmd_name in self.get_sub_commands():
            self.run_command(cmd_name)

        if self.path_file:
            self.create_path_file()

        # write list of installed files, if requested.
        if self.record:
            outputs = self.get_outputs()
            if self.root:               # strip any package prefix
                root_len = len(self.root)
                for counter in range(len(outputs)):
                    outputs[counter] = outputs[counter][root_len:]
            self.execute(write_file,
                         (self.record, outputs),
                         "writing list of installed files to '%s'" %
                         self.record)

        sys_path = map(os.path.normpath, sys.path)
        sys_path = map(os.path.normcase, sys_path)
        install_lib = os.path.normcase(os.path.normpath(self.install_lib))
        if (self.warn_dir and
            not (self.path_file and self.install_path_file) and
            install_lib not in sys_path):
            log.debug(("modules installed to '%s', which is not in "
                       "Python's module search path (sys.path) -- "
                       "you'll have to change the search path yourself"),
                       self.install_lib)

    def create_path_file(self):
        """Creates the .pth file"""
        filename = os.path.join(self.install_libbase,
                                self.path_file + ".pth")
        if self.install_path_file:
            self.execute(write_file,
                         (filename, [self.extra_dirs]),
                         "creating %s" % filename)
        else:
            self.warn("path file '%s' not created" % filename)


    # -- Reporting methods ---------------------------------------------

    def get_outputs(self):
        """Assembles the outputs of all the sub-commands."""
        outputs = []
        for cmd_name in self.get_sub_commands():
            cmd = self.get_finalized_command(cmd_name)
            # Add the contents of cmd.get_outputs(), ensuring
            # that outputs doesn't contain duplicate entries
            for filename in cmd.get_outputs():
                if filename not in outputs:
                    outputs.append(filename)

        if self.path_file and self.install_path_file:
            outputs.append(os.path.join(self.install_libbase,
                                        self.path_file + ".pth"))

        return outputs

    def get_inputs(self):
        """Returns the inputs of all the sub-commands"""
        # XXX gee, this looks familiar ;-(
        inputs = []
        for cmd_name in self.get_sub_commands():
            cmd = self.get_finalized_command(cmd_name)
            inputs.extend(cmd.get_inputs())

        return inputs

    # -- Predicates for sub-command list -------------------------------

    def has_lib(self):
        """Returns true if the current distribution has any Python
        modules to install."""
        return (self.distribution.has_pure_modules() or
                self.distribution.has_ext_modules())

    def has_headers(self):
        """Returns true if the current distribution has any headers to
        install."""
        return self.distribution.has_headers()

    def has_scripts(self):
        """Returns true if the current distribution has any scripts to.
        install."""
        return self.distribution.has_scripts()

    def has_data(self):
        """Returns true if the current distribution has any data to.
        install."""
        return self.distribution.has_data_files()

    # 'sub_commands': a list of commands this command might have to run to
    # get its work done.  See cmd.py for more info.
    sub_commands = [('install_lib',     has_lib),
                    ('install_headers', has_headers),
                    ('install_scripts', has_scripts),
                    ('install_data',    has_data),
                    ('install_egg_info', lambda self:True),
                   ]