setuptools installation method

Signed-off-by: Kenneth Reitz <me@kennethreitz.org>

bin/steps/python

@@ -67,8 +67,9 @@ if [ "$FRESH_PYTHON" ] || [[ ! $(pip --version) == *$PIP_UPDATE* ]]; then
   rm -fr /app/.heroku/python/lib/python*/site-packages/pip-*
   rm -fr /app/.heroku/python/lib/python*/site-packages/setuptools-*
 
+  /app/.heroku/python/bin/python "$ROOT_DIR/vendor/setuptools-39.0.1/setup.py" install # &> /dev/null
   /app/.heroku/python/bin/python "$ROOT_DIR/vendor/pip-9.0.3/setup.py" install # &> /dev/null
-  /app/.heroku/python/bin/pip install "$ROOT_DIR/vendor/setuptools-39.0.1-py2.py3-none-any.whl"
+
 
 fi
 

setuptools.egg-info/entry_points.txt

+
+[distutils.commands]
+egg_info = setuptools.command.egg_info:egg_info
+
+[distutils.setup_keywords]
+include_package_data = setuptools.dist:assert_bool
+install_requires = setuptools.dist:check_requirements
+extras_require = setuptools.dist:check_extras
+entry_points = setuptools.dist:check_entry_points
+
+[egg_info.writers]
+dependency_links.txt = setuptools.command.egg_info:overwrite_arg
+entry_points.txt = setuptools.command.egg_info:write_entries
+requires.txt = setuptools.command.egg_info:write_requirements

vendor/setuptools-39.0.1/LICENSE

+Copyright (C) 2016 Jason R Coombs <jaraco@jaraco.com>
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+of the Software, and to permit persons to whom the Software is furnished to do
+so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

vendor/setuptools-39.0.1/MANIFEST.in

+recursive-include setuptools *.py *.exe *.xml
+recursive-include tests *.py
+recursive-include setuptools/tests *.html
+recursive-include docs *.py *.txt *.conf *.css *.css_t Makefile indexsidebar.html
+recursive-include setuptools/_vendor *
+recursive-include pkg_resources *.py *.txt
+include *.py
+include *.rst
+include MANIFEST.in
+include LICENSE
+include launcher.c
+include msvc-build-launcher.cmd
+include pytest.ini
+include tox.ini

vendor/setuptools-39.0.1/PKG-INFO

+Metadata-Version: 2.1
+Name: setuptools
+Version: 39.0.1
+Summary: Easily download, build, install, upgrade, and uninstall Python packages
+Home-page: https://github.com/pypa/setuptools
+Author: Python Packaging Authority
+Author-email: distutils-sig@python.org
+License: UNKNOWN
+Project-URL: Documentation, https://setuptools.readthedocs.io/
+Description: .. image:: https://img.shields.io/pypi/v/setuptools.svg
+           :target: https://pypi.org/project/setuptools
+        
+        .. image:: https://readthedocs.org/projects/setuptools/badge/?version=latest
+            :target: https://setuptools.readthedocs.io
+        
+        .. image:: https://img.shields.io/travis/pypa/setuptools/master.svg?label=Linux%20build%20%40%20Travis%20CI
+           :target: https://travis-ci.org/pypa/setuptools
+        
+        .. image:: https://img.shields.io/appveyor/ci/jaraco/setuptools/master.svg?label=Windows%20build%20%40%20Appveyor
+           :target: https://ci.appveyor.com/project/jaraco/setuptools/branch/master
+        
+        .. image:: https://img.shields.io/pypi/pyversions/setuptools.svg
+        
+        See the `Installation Instructions
+        <https://packaging.python.org/installing/>`_ in the Python Packaging
+        User's Guide for instructions on installing, upgrading, and uninstalling
+        Setuptools.
+        
+        The project is `maintained at GitHub <https://github.com/pypa/setuptools>`_.
+        
+        Questions and comments should be directed to the `distutils-sig
+        mailing list <http://mail.python.org/pipermail/distutils-sig/>`_.
+        Bug reports and especially tested patches may be
+        submitted directly to the `bug tracker
+        <https://github.com/pypa/setuptools/issues>`_.
+        
+        
+        Code of Conduct
+        ---------------
+        
+        Everyone interacting in the setuptools project's codebases, issue trackers,
+        chat rooms, and mailing lists is expected to follow the
+        `PyPA Code of Conduct <https://www.pypa.io/en/latest/code-of-conduct/>`_.
+        
+Keywords: CPAN PyPI distutils eggs package management
+Platform: UNKNOWN
+Classifier: Development Status :: 5 - Production/Stable
+Classifier: Intended Audience :: Developers
+Classifier: License :: OSI Approved :: MIT License
+Classifier: Operating System :: OS Independent
+Classifier: Programming Language :: Python :: 2
+Classifier: Programming Language :: Python :: 2.7
+Classifier: Programming Language :: Python :: 3
+Classifier: Programming Language :: Python :: 3.3
+Classifier: Programming Language :: Python :: 3.4
+Classifier: Programming Language :: Python :: 3.5
+Classifier: Programming Language :: Python :: 3.6
+Classifier: Topic :: Software Development :: Libraries :: Python Modules
+Classifier: Topic :: System :: Archiving :: Packaging
+Classifier: Topic :: System :: Systems Administration
+Classifier: Topic :: Utilities
+Requires-Python: >=2.7,!=3.0.*,!=3.1.*,!=3.2.*
+Description-Content-Type: text/x-rst; charset=UTF-8
+Provides-Extra: certs
+Provides-Extra: ssl

vendor/setuptools-39.0.1/README.rst

+.. image:: https://img.shields.io/pypi/v/setuptools.svg
+   :target: https://pypi.org/project/setuptools
+
+.. image:: https://readthedocs.org/projects/setuptools/badge/?version=latest
+    :target: https://setuptools.readthedocs.io
+
+.. image:: https://img.shields.io/travis/pypa/setuptools/master.svg?label=Linux%20build%20%40%20Travis%20CI
+   :target: https://travis-ci.org/pypa/setuptools
+
+.. image:: https://img.shields.io/appveyor/ci/jaraco/setuptools/master.svg?label=Windows%20build%20%40%20Appveyor
+   :target: https://ci.appveyor.com/project/jaraco/setuptools/branch/master
+
+.. image:: https://img.shields.io/pypi/pyversions/setuptools.svg
+
+See the `Installation Instructions
+<https://packaging.python.org/installing/>`_ in the Python Packaging
+User's Guide for instructions on installing, upgrading, and uninstalling
+Setuptools.
+
+The project is `maintained at GitHub <https://github.com/pypa/setuptools>`_.
+
+Questions and comments should be directed to the `distutils-sig
+mailing list <http://mail.python.org/pipermail/distutils-sig/>`_.
+Bug reports and especially tested patches may be
+submitted directly to the `bug tracker
+<https://github.com/pypa/setuptools/issues>`_.
+
+
+Code of Conduct
+---------------
+
+Everyone interacting in the setuptools project's codebases, issue trackers,
+chat rooms, and mailing lists is expected to follow the
+`PyPA Code of Conduct <https://www.pypa.io/en/latest/code-of-conduct/>`_.

vendor/setuptools-39.0.1/bootstrap.py

+"""
+If setuptools is not already installed in the environment, it's not possible
+to invoke setuptools' own commands. This routine will bootstrap this local
+environment by creating a minimal egg-info directory and then invoking the
+egg-info command to flesh out the egg-info directory.
+"""
+
+from __future__ import unicode_literals
+
+import os
+import sys
+import textwrap
+import subprocess
+import io
+
+
+minimal_egg_info = textwrap.dedent("""
+    [distutils.commands]
+    egg_info = setuptools.command.egg_info:egg_info
+
+    [distutils.setup_keywords]
+    include_package_data = setuptools.dist:assert_bool
+    install_requires = setuptools.dist:check_requirements
+    extras_require = setuptools.dist:check_extras
+    entry_points = setuptools.dist:check_entry_points
+
+    [egg_info.writers]
+    dependency_links.txt = setuptools.command.egg_info:overwrite_arg
+    entry_points.txt = setuptools.command.egg_info:write_entries
+    requires.txt = setuptools.command.egg_info:write_requirements
+    """)
+
+
+def ensure_egg_info():
+    if os.path.exists('setuptools.egg-info'):
+        return
+    print("adding minimal entry_points")
+    build_egg_info()
+
+
+def build_egg_info():
+    """
+    Build a minimal egg-info, enough to invoke egg_info
+    """
+
+    os.mkdir('setuptools.egg-info')
+    with io.open('setuptools.egg-info/entry_points.txt', 'w') as ep:
+        ep.write(minimal_egg_info)
+
+
+def run_egg_info():
+    cmd = [sys.executable, 'setup.py', 'egg_info']
+    print("Regenerating egg_info")
+    subprocess.check_call(cmd)
+    print("...and again.")
+    subprocess.check_call(cmd)
+
+
+def main():
+    ensure_egg_info()
+    run_egg_info()
+
+
+__name__ == '__main__' and main()

vendor/setuptools-39.0.1/build/lib/easy_install.py

+"""Run the EasyInstall command"""
+
+if __name__ == '__main__':
+    from setuptools.command.easy_install import main
+    main()

vendor/setuptools-39.0.1/build/lib/pkg_resources/_vendor/packaging/__about__.py

+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+from __future__ import absolute_import, division, print_function
+
+__all__ = [
+    "__title__", "__summary__", "__uri__", "__version__", "__author__",
+    "__email__", "__license__", "__copyright__",
+]
+
+__title__ = "packaging"
+__summary__ = "Core utilities for Python packages"
+__uri__ = "https://github.com/pypa/packaging"
+
+__version__ = "16.8"
+
+__author__ = "Donald Stufft and individual contributors"
+__email__ = "donald@stufft.io"
+
+__license__ = "BSD or Apache License, Version 2.0"
+__copyright__ = "Copyright 2014-2016 %s" % __author__

vendor/setuptools-39.0.1/build/lib/pkg_resources/_vendor/packaging/__init__.py

+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+from __future__ import absolute_import, division, print_function
+
+from .__about__ import (
+    __author__, __copyright__, __email__, __license__, __summary__, __title__,
+    __uri__, __version__
+)
+
+__all__ = [
+    "__title__", "__summary__", "__uri__", "__version__", "__author__",
+    "__email__", "__license__", "__copyright__",
+]

vendor/setuptools-39.0.1/build/lib/pkg_resources/_vendor/packaging/_compat.py

+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+from __future__ import absolute_import, division, print_function
+
+import sys
+
+
+PY2 = sys.version_info[0] == 2
+PY3 = sys.version_info[0] == 3
+
+# flake8: noqa
+
+if PY3:
+    string_types = str,
+else:
+    string_types = basestring,
+
+
+def with_metaclass(meta, *bases):
+    """
+    Create a base class with a metaclass.
+    """
+    # This requires a bit of explanation: the basic idea is to make a dummy
+    # metaclass for one level of class instantiation that replaces itself with
+    # the actual metaclass.
+    class metaclass(meta):
+        def __new__(cls, name, this_bases, d):
+            return meta(name, bases, d)
+    return type.__new__(metaclass, 'temporary_class', (), {})

vendor/setuptools-39.0.1/build/lib/pkg_resources/_vendor/packaging/_structures.py

+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+from __future__ import absolute_import, division, print_function
+
+
+class Infinity(object):
+
+    def __repr__(self):
+        return "Infinity"
+
+    def __hash__(self):
+        return hash(repr(self))
+
+    def __lt__(self, other):
+        return False
+
+    def __le__(self, other):
+        return False
+
+    def __eq__(self, other):
+        return isinstance(other, self.__class__)
+
+    def __ne__(self, other):
+        return not isinstance(other, self.__class__)
+
+    def __gt__(self, other):
+        return True
+
+    def __ge__(self, other):
+        return True
+
+    def __neg__(self):
+        return NegativeInfinity
+
+Infinity = Infinity()
+
+
+class NegativeInfinity(object):
+
+    def __repr__(self):
+        return "-Infinity"
+
+    def __hash__(self):
+        return hash(repr(self))
+
+    def __lt__(self, other):
+        return True
+
+    def __le__(self, other):
+        return True
+
+    def __eq__(self, other):
+        return isinstance(other, self.__class__)
+
+    def __ne__(self, other):
+        return not isinstance(other, self.__class__)
+
+    def __gt__(self, other):
+        return False
+
+    def __ge__(self, other):
+        return False
+
+    def __neg__(self):
+        return Infinity
+
+NegativeInfinity = NegativeInfinity()

vendor/setuptools-39.0.1/build/lib/pkg_resources/_vendor/packaging/markers.py

+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+from __future__ import absolute_import, division, print_function
+
+import operator
+import os
+import platform
+import sys
+
+from pkg_resources.extern.pyparsing import ParseException, ParseResults, stringStart, stringEnd
+from pkg_resources.extern.pyparsing import ZeroOrMore, Group, Forward, QuotedString
+from pkg_resources.extern.pyparsing import Literal as L  # noqa
+
+from ._compat import string_types
+from .specifiers import Specifier, InvalidSpecifier
+
+
+__all__ = [
+    "InvalidMarker", "UndefinedComparison", "UndefinedEnvironmentName",
+    "Marker", "default_environment",
+]
+
+
+class InvalidMarker(ValueError):
+    """
+    An invalid marker was found, users should refer to PEP 508.
+    """
+
+
+class UndefinedComparison(ValueError):
+    """
+    An invalid operation was attempted on a value that doesn't support it.
+    """
+
+
+class UndefinedEnvironmentName(ValueError):
+    """
+    A name was attempted to be used that does not exist inside of the
+    environment.
+    """
+
+
+class Node(object):
+
+    def __init__(self, value):
+        self.value = value
+
+    def __str__(self):
+        return str(self.value)
+
+    def __repr__(self):
+        return "<{0}({1!r})>".format(self.__class__.__name__, str(self))
+
+    def serialize(self):
+        raise NotImplementedError
+
+
+class Variable(Node):
+
+    def serialize(self):
+        return str(self)
+
+
+class Value(Node):
+
+    def serialize(self):
+        return '"{0}"'.format(self)
+
+
+class Op(Node):
+
+    def serialize(self):
+        return str(self)
+
+
+VARIABLE = (
+    L("implementation_version") |
+    L("platform_python_implementation") |
+    L("implementation_name") |
+    L("python_full_version") |
+    L("platform_release") |
+    L("platform_version") |
+    L("platform_machine") |
+    L("platform_system") |
+    L("python_version") |
+    L("sys_platform") |
+    L("os_name") |
+    L("os.name") |  # PEP-345
+    L("sys.platform") |  # PEP-345
+    L("platform.version") |  # PEP-345
+    L("platform.machine") |  # PEP-345
+    L("platform.python_implementation") |  # PEP-345
+    L("python_implementation") |  # undocumented setuptools legacy
+    L("extra")
+)
+ALIASES = {
+    'os.name': 'os_name',
+    'sys.platform': 'sys_platform',
+    'platform.version': 'platform_version',
+    'platform.machine': 'platform_machine',
+    'platform.python_implementation': 'platform_python_implementation',
+    'python_implementation': 'platform_python_implementation'
+}
+VARIABLE.setParseAction(lambda s, l, t: Variable(ALIASES.get(t[0], t[0])))
+
+VERSION_CMP = (
+    L("===") |
+    L("==") |
+    L(">=") |
+    L("<=") |
+    L("!=") |
+    L("~=") |
+    L(">") |
+    L("<")
+)
+
+MARKER_OP = VERSION_CMP | L("not in") | L("in")
+MARKER_OP.setParseAction(lambda s, l, t: Op(t[0]))
+
+MARKER_VALUE = QuotedString("'") | QuotedString('"')
+MARKER_VALUE.setParseAction(lambda s, l, t: Value(t[0]))
+
+BOOLOP = L("and") | L("or")
+
+MARKER_VAR = VARIABLE | MARKER_VALUE
+
+MARKER_ITEM = Group(MARKER_VAR + MARKER_OP + MARKER_VAR)
+MARKER_ITEM.setParseAction(lambda s, l, t: tuple(t[0]))
+
+LPAREN = L("(").suppress()
+RPAREN = L(")").suppress()
+
+MARKER_EXPR = Forward()
+MARKER_ATOM = MARKER_ITEM | Group(LPAREN + MARKER_EXPR + RPAREN)
+MARKER_EXPR << MARKER_ATOM + ZeroOrMore(BOOLOP + MARKER_EXPR)
+
+MARKER = stringStart + MARKER_EXPR + stringEnd
+
+
+def _coerce_parse_result(results):
+    if isinstance(results, ParseResults):
+        return [_coerce_parse_result(i) for i in results]
+    else:
+        return results
+
+
+def _format_marker(marker, first=True):
+    assert isinstance(marker, (list, tuple, string_types))
+
+    # Sometimes we have a structure like [[...]] which is a single item list
+    # where the single item is itself it's own list. In that case we want skip
+    # the rest of this function so that we don't get extraneous () on the
+    # outside.
+    if (isinstance(marker, list) and len(marker) == 1 and
+            isinstance(marker[0], (list, tuple))):
+        return _format_marker(marker[0])
+
+    if isinstance(marker, list):
+        inner = (_format_marker(m, first=False) for m in marker)
+        if first:
+            return " ".join(inner)
+        else:
+            return "(" + " ".join(inner) + ")"
+    elif isinstance(marker, tuple):
+        return " ".join([m.serialize() for m in marker])
+    else:
+        return marker
+
+
+_operators = {
+    "in": lambda lhs, rhs: lhs in rhs,
+    "not in": lambda lhs, rhs: lhs not in rhs,
+    "<": operator.lt,
+    "<=": operator.le,
+    "==": operator.eq,
+    "!=": operator.ne,
+    ">=": operator.ge,
+    ">": operator.gt,
+}
+
+
+def _eval_op(lhs, op, rhs):
+    try:
+        spec = Specifier("".join([op.serialize(), rhs]))
+    except InvalidSpecifier:
+        pass
+    else:
+        return spec.contains(lhs)
+
+    oper = _operators.get(op.serialize())
+    if oper is None:
+        raise UndefinedComparison(
+            "Undefined {0!r} on {1!r} and {2!r}.".format(op, lhs, rhs)
+        )
+
+    return oper(lhs, rhs)
+
+
+_undefined = object()
+
+
+def _get_env(environment, name):
+    value = environment.get(name, _undefined)
+
+    if value is _undefined:
+        raise UndefinedEnvironmentName(
+            "{0!r} does not exist in evaluation environment.".format(name)
+        )
+
+    return value
+
+
+def _evaluate_markers(markers, environment):
+    groups = [[]]
+
+    for marker in markers:
+        assert isinstance(marker, (list, tuple, string_types))
+
+        if isinstance(marker, list):
+            groups[-1].append(_evaluate_markers(marker, environment))
+        elif isinstance(marker, tuple):
+            lhs, op, rhs = marker
+
+            if isinstance(lhs, Variable):
+                lhs_value = _get_env(environment, lhs.value)
+                rhs_value = rhs.value
+            else:
+                lhs_value = lhs.value
+                rhs_value = _get_env(environment, rhs.value)
+
+            groups[-1].append(_eval_op(lhs_value, op, rhs_value))
+        else:
+            assert marker in ["and", "or"]
+            if marker == "or":
+                groups.append([])
+
+    return any(all(item) for item in groups)
+
+
+def format_full_version(info):
+    version = '{0.major}.{0.minor}.{0.micro}'.format(info)
+    kind = info.releaselevel
+    if kind != 'final':
+        version += kind[0] + str(info.serial)
+    return version
+
+
+def default_environment():
+    if hasattr(sys, 'implementation'):
+        iver = format_full_version(sys.implementation.version)
+        implementation_name = sys.implementation.name
+    else:
+        iver = '0'
+        implementation_name = ''
+
+    return {
+        "implementation_name": implementation_name,
+        "implementation_version": iver,
+        "os_name": os.name,
+        "platform_machine": platform.machine(),
+        "platform_release": platform.release(),
+        "platform_system": platform.system(),
+        "platform_version": platform.version(),
+        "python_full_version": platform.python_version(),
+        "platform_python_implementation": platform.python_implementation(),
+        "python_version": platform.python_version()[:3],
+        "sys_platform": sys.platform,
+    }
+
+
+class Marker(object):
+
+    def __init__(self, marker):
+        try:
+            self._markers = _coerce_parse_result(MARKER.parseString(marker))
+        except ParseException as e:
+            err_str = "Invalid marker: {0!r}, parse error at {1!r}".format(
+                marker, marker[e.loc:e.loc + 8])
+            raise InvalidMarker(err_str)
+
+    def __str__(self):
+        return _format_marker(self._markers)
+
+    def __repr__(self):
+        return "<Marker({0!r})>".format(str(self))
+
+    def evaluate(self, environment=None):
+        """Evaluate a marker.
+
+        Return the boolean from evaluating the given marker against the
+        environment. environment is an optional argument to override all or
+        part of the determined environment.
+
+        The environment is determined from the current Python process.
+        """
+        current_environment = default_environment()
+        if environment is not None:
+            current_environment.update(environment)
+
+        return _evaluate_markers(self._markers, current_environment)

vendor/setuptools-39.0.1/build/lib/pkg_resources/_vendor/packaging/requirements.py

+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+from __future__ import absolute_import, division, print_function
+
+import string
+import re
+
+from pkg_resources.extern.pyparsing import stringStart, stringEnd, originalTextFor, ParseException
+from pkg_resources.extern.pyparsing import ZeroOrMore, Word, Optional, Regex, Combine
+from pkg_resources.extern.pyparsing import Literal as L  # noqa
+from pkg_resources.extern.six.moves.urllib import parse as urlparse
+
+from .markers import MARKER_EXPR, Marker
+from .specifiers import LegacySpecifier, Specifier, SpecifierSet
+
+
+class InvalidRequirement(ValueError):
+    """
+    An invalid requirement was found, users should refer to PEP 508.
+    """
+
+
+ALPHANUM = Word(string.ascii_letters + string.digits)
+
+LBRACKET = L("[").suppress()
+RBRACKET = L("]").suppress()
+LPAREN = L("(").suppress()
+RPAREN = L(")").suppress()
+COMMA = L(",").suppress()
+SEMICOLON = L(";").suppress()
+AT = L("@").suppress()
+
+PUNCTUATION = Word("-_.")
+IDENTIFIER_END = ALPHANUM | (ZeroOrMore(PUNCTUATION) + ALPHANUM)
+IDENTIFIER = Combine(ALPHANUM + ZeroOrMore(IDENTIFIER_END))
+
+NAME = IDENTIFIER("name")
+EXTRA = IDENTIFIER
+
+URI = Regex(r'[^ ]+')("url")
+URL = (AT + URI)
+
+EXTRAS_LIST = EXTRA + ZeroOrMore(COMMA + EXTRA)
+EXTRAS = (LBRACKET + Optional(EXTRAS_LIST) + RBRACKET)("extras")
+
+VERSION_PEP440 = Regex(Specifier._regex_str, re.VERBOSE | re.IGNORECASE)
+VERSION_LEGACY = Regex(LegacySpecifier._regex_str, re.VERBOSE | re.IGNORECASE)
+
+VERSION_ONE = VERSION_PEP440 ^ VERSION_LEGACY
+VERSION_MANY = Combine(VERSION_ONE + ZeroOrMore(COMMA + VERSION_ONE),
+                       joinString=",", adjacent=False)("_raw_spec")
+_VERSION_SPEC = Optional(((LPAREN + VERSION_MANY + RPAREN) | VERSION_MANY))
+_VERSION_SPEC.setParseAction(lambda s, l, t: t._raw_spec or '')
+
+VERSION_SPEC = originalTextFor(_VERSION_SPEC)("specifier")
+VERSION_SPEC.setParseAction(lambda s, l, t: t[1])
+
+MARKER_EXPR = originalTextFor(MARKER_EXPR())("marker")
+MARKER_EXPR.setParseAction(
+    lambda s, l, t: Marker(s[t._original_start:t._original_end])
+)
+MARKER_SEPERATOR = SEMICOLON
+MARKER = MARKER_SEPERATOR + MARKER_EXPR
+
+VERSION_AND_MARKER = VERSION_SPEC + Optional(MARKER)
+URL_AND_MARKER = URL + Optional(MARKER)
+
+NAMED_REQUIREMENT = \
+    NAME + Optional(EXTRAS) + (URL_AND_MARKER | VERSION_AND_MARKER)
+
+REQUIREMENT = stringStart + NAMED_REQUIREMENT + stringEnd
+
+
+class Requirement(object):
+    """Parse a requirement.
+
+    Parse a given requirement string into its parts, such as name, specifier,
+    URL, and extras. Raises InvalidRequirement on a badly-formed requirement
+    string.
+    """
+
+    # TODO: Can we test whether something is contained within a requirement?
+    #       If so how do we do that? Do we need to test against the _name_ of
+    #       the thing as well as the version? What about the markers?
+    # TODO: Can we normalize the name and extra name?
+
+    def __init__(self, requirement_string):
+        try:
+            req = REQUIREMENT.parseString(requirement_string)
+        except ParseException as e:
+            raise InvalidRequirement(
+                "Invalid requirement, parse error at \"{0!r}\"".format(
+                    requirement_string[e.loc:e.loc + 8]))
+
+        self.name = req.name
+        if req.url:
+            parsed_url = urlparse.urlparse(req.url)
+            if not (parsed_url.scheme and parsed_url.netloc) or (
+                    not parsed_url.scheme and not parsed_url.netloc):
+                raise InvalidRequirement("Invalid URL given")
+            self.url = req.url
+        else:
+            self.url = None
+        self.extras = set(req.extras.asList() if req.extras else [])
+        self.specifier = SpecifierSet(req.specifier)
+        self.marker = req.marker if req.marker else None
+
+    def __str__(self):
+        parts = [self.name]
+
+        if self.extras:
+            parts.append("[{0}]".format(",".join(sorted(self.extras))))
+
+        if self.specifier:
+            parts.append(str(self.specifier))
+
+        if self.url:
+            parts.append("@ {0}".format(self.url))
+
+        if self.marker:
+            parts.append("; {0}".format(self.marker))
+
+        return "".join(parts)
+
+    def __repr__(self):
+        return "<Requirement({0!r})>".format(str(self))