Merge branch 'master' into fix/1557

12 files changed, 1149 insertions, 186 deletions

diff --git a/setuptools/_vendor/ordered_set.py b/setuptools/_vendor/ordered_set.py
new file mode 100644
index 00000000..14876000
--- /dev/null
+++ b/setuptools/_vendor/ordered_set.py
@@ -0,0 +1,488 @@
+"""
+An OrderedSet is a custom MutableSet that remembers its order, so that every
+entry has an index that can be looked up.
+
+Based on a recipe originally posted to ActiveState Recipes by Raymond Hettiger,
+and released under the MIT license.
+"""
+import itertools as it
+from collections import deque
+
+try:
+    # Python 3
+    from collections.abc import MutableSet, Sequence
+except ImportError:
+    # Python 2.7
+    from collections import MutableSet, Sequence
+
+SLICE_ALL = slice(None)
+__version__ = "3.1"
+
+
+def is_iterable(obj):
+    """
+    Are we being asked to look up a list of things, instead of a single thing?
+    We check for the `__iter__` attribute so that this can cover types that
+    don't have to be known by this module, such as NumPy arrays.
+
+    Strings, however, should be considered as atomic values to look up, not
+    iterables. The same goes for tuples, since they are immutable and therefore
+    valid entries.
+
+    We don't need to check for the Python 2 `unicode` type, because it doesn't
+    have an `__iter__` attribute anyway.
+    """
+    return (
+        hasattr(obj, "__iter__")
+        and not isinstance(obj, str)
+        and not isinstance(obj, tuple)
+    )
+
+
+class OrderedSet(MutableSet, Sequence):
+    """
+    An OrderedSet is a custom MutableSet that remembers its order, so that
+    every entry has an index that can be looked up.
+
+    Example:
+        >>> OrderedSet([1, 1, 2, 3, 2])
+        OrderedSet([1, 2, 3])
+    """
+
+    def __init__(self, iterable=None):
+        self.items = []
+        self.map = {}
+        if iterable is not None:
+            self |= iterable
+
+    def __len__(self):
+        """
+        Returns the number of unique elements in the ordered set
+
+        Example:
+            >>> len(OrderedSet([]))
+            0
+            >>> len(OrderedSet([1, 2]))
+            2
+        """
+        return len(self.items)
+
+    def __getitem__(self, index):
+        """
+        Get the item at a given index.
+
+        If `index` is a slice, you will get back that slice of items, as a
+        new OrderedSet.
+
+        If `index` is a list or a similar iterable, you'll get a list of
+        items corresponding to those indices. This is similar to NumPy's
+        "fancy indexing". The result is not an OrderedSet because you may ask
+        for duplicate indices, and the number of elements returned should be
+        the number of elements asked for.
+
+        Example:
+            >>> oset = OrderedSet([1, 2, 3])
+            >>> oset[1]
+            2
+        """
+        if isinstance(index, slice) and index == SLICE_ALL:
+            return self.copy()
+        elif is_iterable(index):
+            return [self.items[i] for i in index]
+        elif hasattr(index, "__index__") or isinstance(index, slice):
+            result = self.items[index]
+            if isinstance(result, list):
+                return self.__class__(result)
+            else:
+                return result
+        else:
+            raise TypeError("Don't know how to index an OrderedSet by %r" % index)
+
+    def copy(self):
+        """
+        Return a shallow copy of this object.
+
+        Example:
+            >>> this = OrderedSet([1, 2, 3])
+            >>> other = this.copy()
+            >>> this == other
+            True
+            >>> this is other
+            False
+        """
+        return self.__class__(self)
+
+    def __getstate__(self):
+        if len(self) == 0:
+            # The state can't be an empty list.
+            # We need to return a truthy value, or else __setstate__ won't be run.
+            #
+            # This could have been done more gracefully by always putting the state
+            # in a tuple, but this way is backwards- and forwards- compatible with
+            # previous versions of OrderedSet.
+            return (None,)
+        else:
+            return list(self)
+
+    def __setstate__(self, state):
+        if state == (None,):
+            self.__init__([])
+        else:
+            self.__init__(state)
+
+    def __contains__(self, key):
+        """
+        Test if the item is in this ordered set
+
+        Example:
+            >>> 1 in OrderedSet([1, 3, 2])
+            True
+            >>> 5 in OrderedSet([1, 3, 2])
+            False
+        """
+        return key in self.map
+
+    def add(self, key):
+        """
+        Add `key` as an item to this OrderedSet, then return its index.
+
+        If `key` is already in the OrderedSet, return the index it already
+        had.
+
+        Example:
+            >>> oset = OrderedSet()
+            >>> oset.append(3)
+            0
+            >>> print(oset)
+            OrderedSet([3])
+        """
+        if key not in self.map:
+            self.map[key] = len(self.items)
+            self.items.append(key)
+        return self.map[key]
+
+    append = add
+
+    def update(self, sequence):
+        """
+        Update the set with the given iterable sequence, then return the index
+        of the last element inserted.
+
+        Example:
+            >>> oset = OrderedSet([1, 2, 3])
+            >>> oset.update([3, 1, 5, 1, 4])
+            4
+            >>> print(oset)
+            OrderedSet([1, 2, 3, 5, 4])
+        """
+        item_index = None
+        try:
+            for item in sequence:
+                item_index = self.add(item)
+        except TypeError:
+            raise ValueError(
+                "Argument needs to be an iterable, got %s" % type(sequence)
+            )
+        return item_index
+
+    def index(self, key):
+        """
+        Get the index of a given entry, raising an IndexError if it's not
+        present.
+
+        `key` can be an iterable of entries that is not a string, in which case
+        this returns a list of indices.
+
+        Example:
+            >>> oset = OrderedSet([1, 2, 3])
+            >>> oset.index(2)
+            1
+        """
+        if is_iterable(key):
+            return [self.index(subkey) for subkey in key]
+        return self.map[key]
+
+    # Provide some compatibility with pd.Index
+    get_loc = index
+    get_indexer = index
+
+    def pop(self):
+        """
+        Remove and return the last element from the set.
+
+        Raises KeyError if the set is empty.
+
+        Example:
+            >>> oset = OrderedSet([1, 2, 3])
+            >>> oset.pop()
+            3
+        """
+        if not self.items:
+            raise KeyError("Set is empty")
+
+        elem = self.items[-1]
+        del self.items[-1]
+        del self.map[elem]
+        return elem
+
+    def discard(self, key):
+        """
+        Remove an element.  Do not raise an exception if absent.
+
+        The MutableSet mixin uses this to implement the .remove() method, which
+        *does* raise an error when asked to remove a non-existent item.
+
+        Example:
+            >>> oset = OrderedSet([1, 2, 3])
+            >>> oset.discard(2)
+            >>> print(oset)
+            OrderedSet([1, 3])
+            >>> oset.discard(2)
+            >>> print(oset)
+            OrderedSet([1, 3])
+        """
+        if key in self:
+            i = self.map[key]
+            del self.items[i]
+            del self.map[key]
+            for k, v in self.map.items():
+                if v >= i:
+                    self.map[k] = v - 1
+
+    def clear(self):
+        """
+        Remove all items from this OrderedSet.
+        """
+        del self.items[:]
+        self.map.clear()
+
+    def __iter__(self):
+        """
+        Example:
+            >>> list(iter(OrderedSet([1, 2, 3])))
+            [1, 2, 3]
+        """
+        return iter(self.items)
+
+    def __reversed__(self):
+        """
+        Example:
+            >>> list(reversed(OrderedSet([1, 2, 3])))
+            [3, 2, 1]
+        """
+        return reversed(self.items)
+
+    def __repr__(self):
+        if not self:
+            return "%s()" % (self.__class__.__name__,)
+        return "%s(%r)" % (self.__class__.__name__, list(self))
+
+    def __eq__(self, other):
+        """
+        Returns true if the containers have the same items. If `other` is a
+        Sequence, then order is checked, otherwise it is ignored.
+
+        Example:
+            >>> oset = OrderedSet([1, 3, 2])
+            >>> oset == [1, 3, 2]
+            True
+            >>> oset == [1, 2, 3]
+            False
+            >>> oset == [2, 3]
+            False
+            >>> oset == OrderedSet([3, 2, 1])
+            False
+        """
+        # In Python 2 deque is not a Sequence, so treat it as one for
+        # consistent behavior with Python 3.
+        if isinstance(other, (Sequence, deque)):
+            # Check that this OrderedSet contains the same elements, in the
+            # same order, as the other object.
+            return list(self) == list(other)
+        try:
+            other_as_set = set(other)
+        except TypeError:
+            # If `other` can't be converted into a set, it's not equal.
+            return False
+        else:
+            return set(self) == other_as_set
+
+    def union(self, *sets):
+        """
+        Combines all unique items.
+        Each items order is defined by its first appearance.
+
+        Example:
+            >>> oset = OrderedSet.union(OrderedSet([3, 1, 4, 1, 5]), [1, 3], [2, 0])
+            >>> print(oset)
+            OrderedSet([3, 1, 4, 5, 2, 0])
+            >>> oset.union([8, 9])
+            OrderedSet([3, 1, 4, 5, 2, 0, 8, 9])
+            >>> oset | {10}
+            OrderedSet([3, 1, 4, 5, 2, 0, 10])
+        """
+        cls = self.__class__ if isinstance(self, OrderedSet) else OrderedSet
+        containers = map(list, it.chain([self], sets))
+        items = it.chain.from_iterable(containers)
+        return cls(items)
+
+    def __and__(self, other):
+        # the parent implementation of this is backwards
+        return self.intersection(other)
+
+    def intersection(self, *sets):
+        """
+        Returns elements in common between all sets. Order is defined only
+        by the first set.
+
+        Example:
+            >>> oset = OrderedSet.intersection(OrderedSet([0, 1, 2, 3]), [1, 2, 3])
+            >>> print(oset)
+            OrderedSet([1, 2, 3])
+            >>> oset.intersection([2, 4, 5], [1, 2, 3, 4])
+            OrderedSet([2])
+            >>> oset.intersection()
+            OrderedSet([1, 2, 3])
+        """
+        cls = self.__class__ if isinstance(self, OrderedSet) else OrderedSet
+        if sets:
+            common = set.intersection(*map(set, sets))
+            items = (item for item in self if item in common)
+        else:
+            items = self
+        return cls(items)
+
+    def difference(self, *sets):
+        """
+        Returns all elements that are in this set but not the others.
+
+        Example:
+            >>> OrderedSet([1, 2, 3]).difference(OrderedSet([2]))
+            OrderedSet([1, 3])
+            >>> OrderedSet([1, 2, 3]).difference(OrderedSet([2]), OrderedSet([3]))
+            OrderedSet([1])
+            >>> OrderedSet([1, 2, 3]) - OrderedSet([2])
+            OrderedSet([1, 3])
+            >>> OrderedSet([1, 2, 3]).difference()
+            OrderedSet([1, 2, 3])
+        """
+        cls = self.__class__
+        if sets:
+            other = set.union(*map(set, sets))
+            items = (item for item in self if item not in other)
+        else:
+            items = self
+        return cls(items)
+
+    def issubset(self, other):
+        """
+        Report whether another set contains this set.
+
+        Example:
+            >>> OrderedSet([1, 2, 3]).issubset({1, 2})
+            False
+            >>> OrderedSet([1, 2, 3]).issubset({1, 2, 3, 4})
+            True
+            >>> OrderedSet([1, 2, 3]).issubset({1, 4, 3, 5})
+            False
+        """
+        if len(self) > len(other):  # Fast check for obvious cases
+            return False
+        return all(item in other for item in self)
+
+    def issuperset(self, other):
+        """
+        Report whether this set contains another set.
+
+        Example:
+            >>> OrderedSet([1, 2]).issuperset([1, 2, 3])
+            False
+            >>> OrderedSet([1, 2, 3, 4]).issuperset({1, 2, 3})
+            True
+            >>> OrderedSet([1, 4, 3, 5]).issuperset({1, 2, 3})
+            False
+        """
+        if len(self) < len(other):  # Fast check for obvious cases
+            return False
+        return all(item in self for item in other)
+
+    def symmetric_difference(self, other):
+        """
+        Return the symmetric difference of two OrderedSets as a new set.
+        That is, the new set will contain all elements that are in exactly
+        one of the sets.
+
+        Their order will be preserved, with elements from `self` preceding
+        elements from `other`.
+
+        Example:
+            >>> this = OrderedSet([1, 4, 3, 5, 7])
+            >>> other = OrderedSet([9, 7, 1, 3, 2])
+            >>> this.symmetric_difference(other)
+            OrderedSet([4, 5, 9, 2])
+        """
+        cls = self.__class__ if isinstance(self, OrderedSet) else OrderedSet
+        diff1 = cls(self).difference(other)
+        diff2 = cls(other).difference(self)
+        return diff1.union(diff2)
+
+    def _update_items(self, items):
+        """
+        Replace the 'items' list of this OrderedSet with a new one, updating
+        self.map accordingly.
+        """
+        self.items = items
+        self.map = {item: idx for (idx, item) in enumerate(items)}
+
+    def difference_update(self, *sets):
+        """
+        Update this OrderedSet to remove items from one or more other sets.
+
+        Example:
+            >>> this = OrderedSet([1, 2, 3])
+            >>> this.difference_update(OrderedSet([2, 4]))
+            >>> print(this)
+            OrderedSet([1, 3])
+
+            >>> this = OrderedSet([1, 2, 3, 4, 5])
+            >>> this.difference_update(OrderedSet([2, 4]), OrderedSet([1, 4, 6]))
+            >>> print(this)
+            OrderedSet([3, 5])
+        """
+        items_to_remove = set()
+        for other in sets:
+            items_to_remove |= set(other)
+        self._update_items([item for item in self.items if item not in items_to_remove])
+
+    def intersection_update(self, other):
+        """
+        Update this OrderedSet to keep only items in another set, preserving
+        their order in this set.
+
+        Example:
+            >>> this = OrderedSet([1, 4, 3, 5, 7])
+            >>> other = OrderedSet([9, 7, 1, 3, 2])
+            >>> this.intersection_update(other)
+            >>> print(this)
+            OrderedSet([1, 3, 7])
+        """
+        other = set(other)
+        self._update_items([item for item in self.items if item in other])
+
+    def symmetric_difference_update(self, other):
+        """
+        Update this OrderedSet to remove items from another set, then
+        add items from the other set that were not present in this set.
+
+        Example:
+            >>> this = OrderedSet([1, 4, 3, 5, 7])
+            >>> other = OrderedSet([9, 7, 1, 3, 2])
+            >>> this.symmetric_difference_update(other)
+            >>> print(this)
+            OrderedSet([4, 5, 9, 2])
+        """
+        items_to_add = [item for item in other if item not in self]
+        items_to_remove = set(other)
+        self._update_items(
+            [item for item in self.items if item not in items_to_remove] + items_to_add
+        )
diff --git a/setuptools/_vendor/packaging/__about__.py b/setuptools/_vendor/packaging/__about__.py
index 95d330ef..dc95138d 100644
--- a/setuptools/_vendor/packaging/__about__.py
+++ b/setuptools/_vendor/packaging/__about__.py
@@ -4,18 +4,24 @@
 from __future__ import absolute_import, division, print_function
 
 __all__ = [
-    "__title__", "__summary__", "__uri__", "__version__", "__author__",
-    "__email__", "__license__", "__copyright__",
+    "__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"
+__version__ = "19.2"
 
 __author__ = "Donald Stufft and individual contributors"
 __email__ = "donald@stufft.io"
 
 __license__ = "BSD or Apache License, Version 2.0"
-__copyright__ = "Copyright 2014-2016 %s" % __author__
+__copyright__ = "Copyright 2014-2019 %s" % __author__
diff --git a/setuptools/_vendor/packaging/__init__.py b/setuptools/_vendor/packaging/__init__.py
index 5ee62202..a0cf67df 100644
--- a/setuptools/_vendor/packaging/__init__.py
+++ b/setuptools/_vendor/packaging/__init__.py
@@ -4,11 +4,23 @@
 from __future__ import absolute_import, division, print_function
 
 from .__about__ import (
-    __author__, __copyright__, __email__, __license__, __summary__, __title__,
-    __uri__, __version__
+    __author__,
+    __copyright__,
+    __email__,
+    __license__,
+    __summary__,
+    __title__,
+    __uri__,
+    __version__,
 )
 
 __all__ = [
-    "__title__", "__summary__", "__uri__", "__version__", "__author__",
-    "__email__", "__license__", "__copyright__",
+    "__title__",
+    "__summary__",
+    "__uri__",
+    "__version__",
+    "__author__",
+    "__email__",
+    "__license__",
+    "__copyright__",
 ]
diff --git a/setuptools/_vendor/packaging/_compat.py b/setuptools/_vendor/packaging/_compat.py
index 210bb80b..25da473c 100644
--- a/setuptools/_vendor/packaging/_compat.py
+++ b/setuptools/_vendor/packaging/_compat.py
@@ -12,9 +12,9 @@ PY3 = sys.version_info[0] == 3
 # flake8: noqa
 
 if PY3:
-    string_types = str,
+    string_types = (str,)
 else:
-    string_types = basestring,
+    string_types = (basestring,)
 
 
 def with_metaclass(meta, *bases):
@@ -27,4 +27,5 @@ def with_metaclass(meta, *bases):
     class metaclass(meta):
         def __new__(cls, name, this_bases, d):
             return meta(name, bases, d)
-    return type.__new__(metaclass, 'temporary_class', (), {})
+
+    return type.__new__(metaclass, "temporary_class", (), {})
diff --git a/setuptools/_vendor/packaging/_structures.py b/setuptools/_vendor/packaging/_structures.py
index ccc27861..68dcca63 100644
--- a/setuptools/_vendor/packaging/_structures.py
+++ b/setuptools/_vendor/packaging/_structures.py
@@ -5,7 +5,6 @@ from __future__ import absolute_import, division, print_function
 
 
 class Infinity(object):
-
     def __repr__(self):
         return "Infinity"
 
@@ -33,11 +32,11 @@ class Infinity(object):
     def __neg__(self):
         return NegativeInfinity
 
+
 Infinity = Infinity()
 
 
 class NegativeInfinity(object):
-
     def __repr__(self):
         return "-Infinity"
 
@@ -65,4 +64,5 @@ class NegativeInfinity(object):
     def __neg__(self):
         return Infinity
 
+
 NegativeInfinity = NegativeInfinity()
diff --git a/setuptools/_vendor/packaging/markers.py b/setuptools/_vendor/packaging/markers.py
index 031332a3..4bdfdb24 100644
--- a/setuptools/_vendor/packaging/markers.py
+++ b/setuptools/_vendor/packaging/markers.py
@@ -17,8 +17,11 @@ from .specifiers import Specifier, InvalidSpecifier
 
 
 __all__ = [
-    "InvalidMarker", "UndefinedComparison", "UndefinedEnvironmentName",
-    "Marker", "default_environment",
+    "InvalidMarker",
+    "UndefinedComparison",
+    "UndefinedEnvironmentName",
+    "Marker",
+    "default_environment",
 ]
 
 
@@ -42,7 +45,6 @@ class UndefinedEnvironmentName(ValueError):
 
 
 class Node(object):
-
     def __init__(self, value):
         self.value = value
 
@@ -57,62 +59,52 @@ class Node(object):
 
 
 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")
+    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")
+    | L("sys.platform")  # PEP-345
+    | L("platform.version")  # PEP-345
+    | L("platform.machine")  # PEP-345
+    | L("platform.python_implementation")  # PEP-345
+    | L("python_implementation")  # PEP-345
+    | L("extra")  # undocumented setuptools legacy
 )
 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'
+    "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("<")
+    L("===") | L("==") | L(">=") | L("<=") | L("!=") | L("~=") | L(">") | L("<")
 )
 
 MARKER_OP = VERSION_CMP | L("not in") | L("in")
@@ -152,8 +144,11 @@ def _format_marker(marker, first=True):
     # 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))):
+    if (
+        isinstance(marker, list)
+        and len(marker) == 1
+        and isinstance(marker[0], (list, tuple))
+    ):
         return _format_marker(marker[0])
 
     if isinstance(marker, list):
@@ -239,20 +234,20 @@ def _evaluate_markers(markers, environment):
 
 
 def format_full_version(info):
-    version = '{0.major}.{0.minor}.{0.micro}'.format(info)
+    version = "{0.major}.{0.minor}.{0.micro}".format(info)
     kind = info.releaselevel
-    if kind != 'final':
+    if kind != "final":
         version += kind[0] + str(info.serial)
     return version
 
 
 def default_environment():
-    if hasattr(sys, 'implementation'):
+    if hasattr(sys, "implementation"):
         iver = format_full_version(sys.implementation.version)
         implementation_name = sys.implementation.name
     else:
-        iver = '0'
-        implementation_name = ''
+        iver = "0"
+        implementation_name = ""
 
     return {
         "implementation_name": implementation_name,
@@ -264,19 +259,19 @@ def default_environment():
         "platform_version": platform.version(),
         "python_full_version": platform.python_version(),
         "platform_python_implementation": platform.python_implementation(),
-        "python_version": platform.python_version()[:3],
+        "python_version": ".".join(platform.python_version_tuple()[:2]),
         "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])
+                marker, marker[e.loc : e.loc + 8]
+            )
             raise InvalidMarker(err_str)
 
     def __str__(self):
diff --git a/setuptools/_vendor/packaging/requirements.py b/setuptools/_vendor/packaging/requirements.py
index 5b493416..8a0c2cb9 100644
--- a/setuptools/_vendor/packaging/requirements.py
+++ b/setuptools/_vendor/packaging/requirements.py
@@ -38,8 +38,8 @@ IDENTIFIER = Combine(ALPHANUM + ZeroOrMore(IDENTIFIER_END))
 NAME = IDENTIFIER("name")
 EXTRA = IDENTIFIER
 
-URI = Regex(r'[^ ]+')("url")
-URL = (AT + URI)
+URI = Regex(r"[^ ]+")("url")
+URL = AT + URI
 
 EXTRAS_LIST = EXTRA + ZeroOrMore(COMMA + EXTRA)
 EXTRAS = (LBRACKET + Optional(EXTRAS_LIST) + RBRACKET)("extras")
@@ -48,28 +48,31 @@ 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_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.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])
+    lambda s, l, t: Marker(s[t._original_start : t._original_end])
 )
-MARKER_SEPERATOR = SEMICOLON
-MARKER = MARKER_SEPERATOR + MARKER_EXPR
+MARKER_SEPARATOR = SEMICOLON
+MARKER = MARKER_SEPARATOR + 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)
+NAMED_REQUIREMENT = NAME + Optional(EXTRAS) + (URL_AND_MARKER | VERSION_AND_MARKER)
 
 REQUIREMENT = stringStart + NAMED_REQUIREMENT + stringEnd
+# setuptools.extern.pyparsing isn't thread safe during initialization, so we do it eagerly, see
+# issue #104
+REQUIREMENT.parseString("x[]")
 
 
 class Requirement(object):
@@ -90,15 +93,21 @@ class Requirement(object):
             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]))
+                'Parse error at "{0!r}": {1}'.format(
+                    requirement_string[e.loc : e.loc + 8], e.msg
+                )
+            )
 
         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")
+            if parsed_url.scheme == "file":
+                if urlparse.urlunparse(parsed_url) != req.url:
+                    raise InvalidRequirement("Invalid URL given")
+            elif not (parsed_url.scheme and parsed_url.netloc) or (
+                not parsed_url.scheme and not parsed_url.netloc
+            ):
+                raise InvalidRequirement("Invalid URL: {0}".format(req.url))
             self.url = req.url
         else:
             self.url = None
@@ -117,6 +126,8 @@ class Requirement(object):
 
         if self.url:
             parts.append("@ {0}".format(self.url))
+            if self.marker:
+                parts.append(" ")
 
         if self.marker:
             parts.append("; {0}".format(self.marker))
diff --git a/setuptools/_vendor/packaging/specifiers.py b/setuptools/_vendor/packaging/specifiers.py
index 7f5a76cf..743576a0 100644
--- a/setuptools/_vendor/packaging/specifiers.py
+++ b/setuptools/_vendor/packaging/specifiers.py
@@ -19,7 +19,6 @@ class InvalidSpecifier(ValueError):
 
 
 class BaseSpecifier(with_metaclass(abc.ABCMeta, object)):
-
     @abc.abstractmethod
     def __str__(self):
         """
@@ -84,10 +83,7 @@ class _IndividualSpecifier(BaseSpecifier):
         if not match:
             raise InvalidSpecifier("Invalid specifier: '{0}'".format(spec))
 
-        self._spec = (
-            match.group("operator").strip(),
-            match.group("version").strip(),
-        )
+        self._spec = (match.group("operator").strip(), match.group("version").strip())
 
         # Store whether or not this Specifier should accept prereleases
         self._prereleases = prereleases
@@ -99,11 +95,7 @@ class _IndividualSpecifier(BaseSpecifier):
             else ""
         )
 
-        return "<{0}({1!r}{2})>".format(
-            self.__class__.__name__,
-            str(self),
-            pre,
-        )
+        return "<{0}({1!r}{2})>".format(self.__class__.__name__, str(self), pre)
 
     def __str__(self):
         return "{0}{1}".format(*self._spec)
@@ -194,11 +186,12 @@ class _IndividualSpecifier(BaseSpecifier):
                 # If our version is a prerelease, and we were not set to allow
                 # prereleases, then we'll store it for later incase nothing
                 # else matches this specifier.
-                if (parsed_version.is_prerelease and not
-                        (prereleases or self.prereleases)):
+                if parsed_version.is_prerelease and not (
+                    prereleases or self.prereleases
+                ):
                     found_prereleases.append(version)
                 # Either this is not a prerelease, or we should have been
-                # accepting prereleases from the begining.
+                # accepting prereleases from the beginning.
                 else:
                     yielded = True
                     yield version
@@ -213,8 +206,7 @@ class _IndividualSpecifier(BaseSpecifier):
 
 class LegacySpecifier(_IndividualSpecifier):
 
-    _regex_str = (
-        r"""
+    _regex_str = r"""
         (?P<operator>(==|!=|<=|>=|<|>))
         \s*
         (?P<version>
@@ -225,10 +217,8 @@ class LegacySpecifier(_IndividualSpecifier):
                       # them, and a comma since it's a version separator.
         )
         """
-    )
 
-    _regex = re.compile(
-        r"^\s*" + _regex_str + r"\s*$", re.VERBOSE | re.IGNORECASE)
+    _regex = re.compile(r"^\s*" + _regex_str + r"\s*$", re.VERBOSE | re.IGNORECASE)
 
     _operators = {
         "==": "equal",
@@ -269,13 +259,13 @@ def _require_version_compare(fn):
         if not isinstance(prospective, Version):
             return False
         return fn(self, prospective, spec)
+
     return wrapped
 
 
 class Specifier(_IndividualSpecifier):
 
-    _regex_str = (
-        r"""
+    _regex_str = r"""
         (?P<operator>(~=|==|!=|<=|>=|<|>|===))
         (?P<version>
             (?:
@@ -367,10 +357,8 @@ class Specifier(_IndividualSpecifier):
             )
         )
         """
-    )
 
-    _regex = re.compile(
-        r"^\s*" + _regex_str + r"\s*$", re.VERBOSE | re.IGNORECASE)
+    _regex = re.compile(r"^\s*" + _regex_str + r"\s*$", re.VERBOSE | re.IGNORECASE)
 
     _operators = {
         "~=": "compatible",
@@ -397,8 +385,7 @@ class Specifier(_IndividualSpecifier):
         prefix = ".".join(
             list(
                 itertools.takewhile(
-                    lambda x: (not x.startswith("post") and not
-                               x.startswith("dev")),
+                    lambda x: (not x.startswith("post") and not x.startswith("dev")),
                     _version_split(spec),
                 )
             )[:-1]
@@ -407,8 +394,9 @@ class Specifier(_IndividualSpecifier):
         # Add the prefix notation to the end of our string
         prefix += ".*"
 
-        return (self._get_operator(">=")(prospective, spec) and
-                self._get_operator("==")(prospective, prefix))
+        return self._get_operator(">=")(prospective, spec) and self._get_operator("==")(
+            prospective, prefix
+        )
 
     @_require_version_compare
     def _compare_equal(self, prospective, spec):
@@ -428,7 +416,7 @@ class Specifier(_IndividualSpecifier):
             # Shorten the prospective version to be the same length as the spec
             # so that we can determine if the specifier is a prefix of the
             # prospective version or not.
-            prospective = prospective[:len(spec)]
+            prospective = prospective[: len(spec)]
 
             # Pad out our two sides with zeros so that they both equal the same
             # length.
@@ -503,7 +491,7 @@ class Specifier(_IndividualSpecifier):
                 return False
 
         # Ensure that we do not allow a local version of the version mentioned
-        # in the specifier, which is techincally greater than, to match.
+        # in the specifier, which is technically greater than, to match.
         if prospective.local is not None:
             if Version(prospective.base_version) == Version(spec.base_version):
                 return False
@@ -567,27 +555,17 @@ def _pad_version(left, right):
     right_split.append(list(itertools.takewhile(lambda x: x.isdigit(), right)))
 
     # Get the rest of our versions
-    left_split.append(left[len(left_split[0]):])
-    right_split.append(right[len(right_split[0]):])
+    left_split.append(left[len(left_split[0]) :])
+    right_split.append(right[len(right_split[0]) :])
 
     # Insert our padding
-    left_split.insert(
-        1,
-        ["0"] * max(0, len(right_split[0]) - len(left_split[0])),
-    )
-    right_split.insert(
-        1,
-        ["0"] * max(0, len(left_split[0]) - len(right_split[0])),
-    )
+    left_split.insert(1, ["0"] * max(0, len(right_split[0]) - len(left_split[0])))
+    right_split.insert(1, ["0"] * max(0, len(left_split[0]) - len(right_split[0])))
 
-    return (
-        list(itertools.chain(*left_split)),
-        list(itertools.chain(*right_split)),
-    )
+    return (list(itertools.chain(*left_split)), list(itertools.chain(*right_split)))
 
 
 class SpecifierSet(BaseSpecifier):
-
     def __init__(self, specifiers="", prereleases=None):
         # Split on , to break each indidivual specifier into it's own item, and
         # strip each item to remove leading/trailing whitespace.
@@ -721,10 +699,7 @@ class SpecifierSet(BaseSpecifier):
         # given version is contained within all of them.
         # Note: This use of all() here means that an empty set of specifiers
         #       will always return True, this is an explicit design decision.
-        return all(
-            s.contains(item, prereleases=prereleases)
-            for s in self._specs
-        )
+        return all(s.contains(item, prereleases=prereleases) for s in self._specs)
 
     def filter(self, iterable, prereleases=None):
         # Determine if we're forcing a prerelease or not, if we're not forcing
diff --git a/setuptools/_vendor/packaging/tags.py b/setuptools/_vendor/packaging/tags.py
new file mode 100644
index 00000000..ec9942f0
--- /dev/null
+++ b/setuptools/_vendor/packaging/tags.py
@@ -0,0 +1,404 @@
+# 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
+
+import distutils.util
+
+try:
+    from importlib.machinery import EXTENSION_SUFFIXES
+except ImportError:  # pragma: no cover
+    import imp
+
+    EXTENSION_SUFFIXES = [x[0] for x in imp.get_suffixes()]
+    del imp
+import platform
+import re
+import sys
+import sysconfig
+import warnings
+
+
+INTERPRETER_SHORT_NAMES = {
+    "python": "py",  # Generic.
+    "cpython": "cp",
+    "pypy": "pp",
+    "ironpython": "ip",
+    "jython": "jy",
+}
+
+
+_32_BIT_INTERPRETER = sys.maxsize <= 2 ** 32
+
+
+class Tag(object):
+
+    __slots__ = ["_interpreter", "_abi", "_platform"]
+
+    def __init__(self, interpreter, abi, platform):
+        self._interpreter = interpreter.lower()
+        self._abi = abi.lower()
+        self._platform = platform.lower()
+
+    @property
+    def interpreter(self):
+        return self._interpreter
+
+    @property
+    def abi(self):
+        return self._abi
+
+    @property
+    def platform(self):
+        return self._platform
+
+    def __eq__(self, other):
+        return (
+            (self.platform == other.platform)
+            and (self.abi == other.abi)
+            and (self.interpreter == other.interpreter)
+        )
+
+    def __hash__(self):
+        return hash((self._interpreter, self._abi, self._platform))
+
+    def __str__(self):
+        return "{}-{}-{}".format(self._interpreter, self._abi, self._platform)
+
+    def __repr__(self):
+        return "<{self} @ {self_id}>".format(self=self, self_id=id(self))
+
+
+def parse_tag(tag):
+    tags = set()
+    interpreters, abis, platforms = tag.split("-")
+    for interpreter in interpreters.split("."):
+        for abi in abis.split("."):
+            for platform_ in platforms.split("."):
+                tags.add(Tag(interpreter, abi, platform_))
+    return frozenset(tags)
+
+
+def _normalize_string(string):
+    return string.replace(".", "_").replace("-", "_")
+
+
+def _cpython_interpreter(py_version):
+    # TODO: Is using py_version_nodot for interpreter version critical?
+    return "cp{major}{minor}".format(major=py_version[0], minor=py_version[1])
+
+
+def _cpython_abis(py_version):
+    abis = []
+    version = "{}{}".format(*py_version[:2])
+    debug = pymalloc = ucs4 = ""
+    with_debug = sysconfig.get_config_var("Py_DEBUG")
+    has_refcount = hasattr(sys, "gettotalrefcount")
+    # Windows doesn't set Py_DEBUG, so checking for support of debug-compiled
+    # extension modules is the best option.
+    # https://github.com/pypa/pip/issues/3383#issuecomment-173267692
+    has_ext = "_d.pyd" in EXTENSION_SUFFIXES
+    if with_debug or (with_debug is None and (has_refcount or has_ext)):
+        debug = "d"
+    if py_version < (3, 8):
+        with_pymalloc = sysconfig.get_config_var("WITH_PYMALLOC")
+        if with_pymalloc or with_pymalloc is None:
+            pymalloc = "m"
+        if py_version < (3, 3):
+            unicode_size = sysconfig.get_config_var("Py_UNICODE_SIZE")
+            if unicode_size == 4 or (
+                unicode_size is None and sys.maxunicode == 0x10FFFF
+            ):
+                ucs4 = "u"
+    elif debug:
+        # Debug builds can also load "normal" extension modules.
+        # We can also assume no UCS-4 or pymalloc requirement.
+        abis.append("cp{version}".format(version=version))
+    abis.insert(
+        0,
+        "cp{version}{debug}{pymalloc}{ucs4}".format(
+            version=version, debug=debug, pymalloc=pymalloc, ucs4=ucs4
+        ),
+    )
+    return abis
+
+
+def _cpython_tags(py_version, interpreter, abis, platforms):
+    for abi in abis:
+        for platform_ in platforms:
+            yield Tag(interpreter, abi, platform_)
+    for tag in (Tag(interpreter, "abi3", platform_) for platform_ in platforms):
+        yield tag
+    for tag in (Tag(interpreter, "none", platform_) for platform_ in platforms):
+        yield tag
+    # PEP 384 was first implemented in Python 3.2.
+    for minor_version in range(py_version[1] - 1, 1, -1):
+        for platform_ in platforms:
+            interpreter = "cp{major}{minor}".format(
+                major=py_version[0], minor=minor_version
+            )
+            yield Tag(interpreter, "abi3", platform_)
+
+
+def _pypy_interpreter():
+    return "pp{py_major}{pypy_major}{pypy_minor}".format(
+        py_major=sys.version_info[0],
+        pypy_major=sys.pypy_version_info.major,
+        pypy_minor=sys.pypy_version_info.minor,
+    )
+
+
+def _generic_abi():
+    abi = sysconfig.get_config_var("SOABI")
+    if abi:
+        return _normalize_string(abi)
+    else:
+        return "none"
+
+
+def _pypy_tags(py_version, interpreter, abi, platforms):
+    for tag in (Tag(interpreter, abi, platform) for platform in platforms):
+        yield tag
+    for tag in (Tag(interpreter, "none", platform) for platform in platforms):
+        yield tag
+
+
+def _generic_tags(interpreter, py_version, abi, platforms):
+    for tag in (Tag(interpreter, abi, platform) for platform in platforms):
+        yield tag
+    if abi != "none":
+        tags = (Tag(interpreter, "none", platform_) for platform_ in platforms)
+        for tag in tags:
+            yield tag
+
+
+def _py_interpreter_range(py_version):
+    """
+    Yield Python versions in descending order.
+
+    After the latest version, the major-only version will be yielded, and then
+    all following versions up to 'end'.
+    """
+    yield "py{major}{minor}".format(major=py_version[0], minor=py_version[1])
+    yield "py{major}".format(major=py_version[0])
+    for minor in range(py_version[1] - 1, -1, -1):
+        yield "py{major}{minor}".format(major=py_version[0], minor=minor)
+
+
+def _independent_tags(interpreter, py_version, platforms):
+    """
+    Return the sequence of tags that are consistent across implementations.
+
+    The tags consist of:
+    - py*-none-<platform>
+    - <interpreter>-none-any
+    - py*-none-any
+    """
+    for version in _py_interpreter_range(py_version):
+        for platform_ in platforms:
+            yield Tag(version, "none", platform_)
+    yield Tag(interpreter, "none", "any")
+    for version in _py_interpreter_range(py_version):
+        yield Tag(version, "none", "any")
+
+
+def _mac_arch(arch, is_32bit=_32_BIT_INTERPRETER):
+    if not is_32bit:
+        return arch
+
+    if arch.startswith("ppc"):
+        return "ppc"
+
+    return "i386"
+
+
+def _mac_binary_formats(version, cpu_arch):
+    formats = [cpu_arch]
+    if cpu_arch == "x86_64":
+        if version < (10, 4):
+            return []
+        formats.extend(["intel", "fat64", "fat32"])
+
+    elif cpu_arch == "i386":
+        if version < (10, 4):
+            return []
+        formats.extend(["intel", "fat32", "fat"])
+
+    elif cpu_arch == "ppc64":
+        # TODO: Need to care about 32-bit PPC for ppc64 through 10.2?
+        if version > (10, 5) or version < (10, 4):
+            return []
+        formats.append("fat64")
+
+    elif cpu_arch == "ppc":
+        if version > (10, 6):
+            return []
+        formats.extend(["fat32", "fat"])
+
+    formats.append("universal")
+    return formats
+
+
+def _mac_platforms(version=None, arch=None):
+    version_str, _, cpu_arch = platform.mac_ver()
+    if version is None:
+        version = tuple(map(int, version_str.split(".")[:2]))
+    if arch is None:
+        arch = _mac_arch(cpu_arch)
+    platforms = []
+    for minor_version in range(version[1], -1, -1):
+        compat_version = version[0], minor_version
+        binary_formats = _mac_binary_formats(compat_version, arch)
+        for binary_format in binary_formats:
+            platforms.append(
+                "macosx_{major}_{minor}_{binary_format}".format(
+                    major=compat_version[0],
+                    minor=compat_version[1],
+                    binary_format=binary_format,
+                )
+            )
+    return platforms
+
+
+# From PEP 513.
+def _is_manylinux_compatible(name, glibc_version):
+    # Check for presence of _manylinux module.
+    try:
+        import _manylinux
+
+        return bool(getattr(_manylinux, name + "_compatible"))
+    except (ImportError, AttributeError):
+        # Fall through to heuristic check below.
+        pass
+
+    return _have_compatible_glibc(*glibc_version)
+
+
+def _glibc_version_string():
+    # Returns glibc version string, or None if not using glibc.
+    import ctypes
+
+    # ctypes.CDLL(None) internally calls dlopen(NULL), and as the dlopen
+    # manpage says, "If filename is NULL, then the returned handle is for the
+    # main program". This way we can let the linker do the work to figure out
+    # which libc our process is actually using.
+    process_namespace = ctypes.CDLL(None)
+    try:
+        gnu_get_libc_version = process_namespace.gnu_get_libc_version
+    except AttributeError:
+        # Symbol doesn't exist -> therefore, we are not linked to
+        # glibc.
+        return None
+
+    # Call gnu_get_libc_version, which returns a string like "2.5"
+    gnu_get_libc_version.restype = ctypes.c_char_p
+    version_str = gnu_get_libc_version()
+    # py2 / py3 compatibility:
+    if not isinstance(version_str, str):
+        version_str = version_str.decode("ascii")
+
+    return version_str
+
+
+# Separated out from have_compatible_glibc for easier unit testing.
+def _check_glibc_version(version_str, required_major, minimum_minor):
+    # Parse string and check against requested version.
+    #
+    # We use a regexp instead of str.split because we want to discard any
+    # random junk that might come after the minor version -- this might happen
+    # in patched/forked versions of glibc (e.g. Linaro's version of glibc
+    # uses version strings like "2.20-2014.11"). See gh-3588.
+    m = re.match(r"(?P<major>[0-9]+)\.(?P<minor>[0-9]+)", version_str)
+    if not m:
+        warnings.warn(
+            "Expected glibc version with 2 components major.minor,"
+            " got: %s" % version_str,
+            RuntimeWarning,
+        )
+        return False
+    return (
+        int(m.group("major")) == required_major
+        and int(m.group("minor")) >= minimum_minor
+    )
+
+
+def _have_compatible_glibc(required_major, minimum_minor):
+    version_str = _glibc_version_string()
+    if version_str is None:
+        return False
+    return _check_glibc_version(version_str, required_major, minimum_minor)
+
+
+def _linux_platforms(is_32bit=_32_BIT_INTERPRETER):
+    linux = _normalize_string(distutils.util.get_platform())
+    if linux == "linux_x86_64" and is_32bit:
+        linux = "linux_i686"
+    manylinux_support = (
+        ("manylinux2014", (2, 17)),  # CentOS 7 w/ glibc 2.17 (PEP 599)
+        ("manylinux2010", (2, 12)),  # CentOS 6 w/ glibc 2.12 (PEP 571)
+        ("manylinux1", (2, 5)),  # CentOS 5 w/ glibc 2.5 (PEP 513)
+    )
+    manylinux_support_iter = iter(manylinux_support)
+    for name, glibc_version in manylinux_support_iter:
+        if _is_manylinux_compatible(name, glibc_version):
+            platforms = [linux.replace("linux", name)]
+            break
+    else:
+        platforms = []
+    # Support for a later manylinux implies support for an earlier version.
+    platforms += [linux.replace("linux", name) for name, _ in manylinux_support_iter]
+    platforms.append(linux)
+    return platforms
+
+
+def _generic_platforms():
+    platform = _normalize_string(distutils.util.get_platform())
+    return [platform]
+
+
+def _interpreter_name():
+    name = platform.python_implementation().lower()
+    return INTERPRETER_SHORT_NAMES.get(name) or name
+
+
+def _generic_interpreter(name, py_version):
+    version = sysconfig.get_config_var("py_version_nodot")
+    if not version:
+        version = "".join(map(str, py_version[:2]))
+    return "{name}{version}".format(name=name, version=version)
+
+
+def sys_tags():
+    """
+    Returns the sequence of tag triples for the running interpreter.
+
+    The order of the sequence corresponds to priority order for the
+    interpreter, from most to least important.
+    """
+    py_version = sys.version_info[:2]
+    interpreter_name = _interpreter_name()
+    if platform.system() == "Darwin":
+        platforms = _mac_platforms()
+    elif platform.system() == "Linux":
+        platforms = _linux_platforms()
+    else:
+        platforms = _generic_platforms()
+
+    if interpreter_name == "cp":
+        interpreter = _cpython_interpreter(py_version)
+        abis = _cpython_abis(py_version)
+        for tag in _cpython_tags(py_version, interpreter, abis, platforms):
+            yield tag
+    elif interpreter_name == "pp":
+        interpreter = _pypy_interpreter()
+        abi = _generic_abi()
+        for tag in _pypy_tags(py_version, interpreter, abi, platforms):
+            yield tag
+    else:
+        interpreter = _generic_interpreter(interpreter_name, py_version)
+        abi = _generic_abi()
+        for tag in _generic_tags(interpreter, py_version, abi, platforms):
+            yield tag
+    for tag in _independent_tags(interpreter, py_version, platforms):
+        yield tag
diff --git a/setuptools/_vendor/packaging/utils.py b/setuptools/_vendor/packaging/utils.py
index 942387ce..88418786 100644
--- a/setuptools/_vendor/packaging/utils.py
+++ b/setuptools/_vendor/packaging/utils.py
@@ -5,6 +5,8 @@ from __future__ import absolute_import, division, print_function
 
 import re
 
+from .version import InvalidVersion, Version
+
 
 _canonicalize_regex = re.compile(r"[-_.]+")
 
@@ -12,3 +14,44 @@ _canonicalize_regex = re.compile(r"[-_.]+")
 def canonicalize_name(name):
     # This is taken from PEP 503.
     return _canonicalize_regex.sub("-", name).lower()
+
+
+def canonicalize_version(version):
+    """
+    This is very similar to Version.__str__, but has one subtle differences
+    with the way it handles the release segment.
+    """
+
+    try:
+        version = Version(version)
+    except InvalidVersion:
+        # Legacy versions cannot be normalized
+        return version
+
+    parts = []
+
+    # Epoch
+    if version.epoch != 0:
+        parts.append("{0}!".format(version.epoch))
+
+    # Release segment
+    # NB: This strips trailing '.0's to normalize
+    parts.append(re.sub(r"(\.0)+$", "", ".".join(str(x) for x in version.release)))
+
+    # Pre-release
+    if version.pre is not None:
+        parts.append("".join(str(x) for x in version.pre))
+
+    # Post-release
+    if version.post is not None:
+        parts.append(".post{0}".format(version.post))
+
+    # Development release
+    if version.dev is not None:
+        parts.append(".dev{0}".format(version.dev))
+
+    # Local version segment
+    if version.local is not None:
+        parts.append("+{0}".format(version.local))
+
+    return "".join(parts)
diff --git a/setuptools/_vendor/packaging/version.py b/setuptools/_vendor/packaging/version.py
index 83b5ee8c..95157a1f 100644
--- a/setuptools/_vendor/packaging/version.py
+++ b/setuptools/_vendor/packaging/version.py
@@ -10,14 +10,11 @@ import re
 from ._structures import Infinity
 
 
-__all__ = [
-    "parse", "Version", "LegacyVersion", "InvalidVersion", "VERSION_PATTERN"
-]
+__all__ = ["parse", "Version", "LegacyVersion", "InvalidVersion", "VERSION_PATTERN"]
 
 
 _Version = collections.namedtuple(
-    "_Version",
-    ["epoch", "release", "dev", "pre", "post", "local"],
+    "_Version", ["epoch", "release", "dev", "pre", "post", "local"]
 )
 
 
@@ -40,7 +37,6 @@ class InvalidVersion(ValueError):
 
 
 class _BaseVersion(object):
-
     def __hash__(self):
         return hash(self._key)
 
@@ -70,7 +66,6 @@ class _BaseVersion(object):
 
 
 class LegacyVersion(_BaseVersion):
-
     def __init__(self, version):
         self._version = str(version)
         self._key = _legacy_cmpkey(self._version)
@@ -90,6 +85,26 @@ class LegacyVersion(_BaseVersion):
         return self._version
 
     @property
+    def epoch(self):
+        return -1
+
+    @property
+    def release(self):
+        return None
+
+    @property
+    def pre(self):
+        return None
+
+    @property
+    def post(self):
+        return None
+
+    @property
+    def dev(self):
+        return None
+
+    @property
     def local(self):
         return None
 
@@ -101,13 +116,19 @@ class LegacyVersion(_BaseVersion):
     def is_postrelease(self):
         return False
 
+    @property
+    def is_devrelease(self):
+        return False
 
-_legacy_version_component_re = re.compile(
-    r"(\d+ | [a-z]+ | \.| -)", re.VERBOSE,
-)
+
+_legacy_version_component_re = re.compile(r"(\d+ | [a-z]+ | \.| -)", re.VERBOSE)
 
 _legacy_version_replacement_map = {
-    "pre": "c", "preview": "c", "-": "final-", "rc": "c", "dev": "@",
+    "pre": "c",
+    "preview": "c",
+    "-": "final-",
+    "rc": "c",
+    "dev": "@",
 }
 
 
@@ -154,6 +175,7 @@ def _legacy_cmpkey(version):
 
     return epoch, parts
 
+
 # Deliberately not anchored to the start and end of the string, to make it
 # easier for 3rd party code to reuse
 VERSION_PATTERN = r"""
@@ -190,10 +212,7 @@ VERSION_PATTERN = r"""
 
 class Version(_BaseVersion):
 
-    _regex = re.compile(
-        r"^\s*" + VERSION_PATTERN + r"\s*$",
-        re.VERBOSE | re.IGNORECASE,
-    )
+    _regex = re.compile(r"^\s*" + VERSION_PATTERN + r"\s*$", re.VERBOSE | re.IGNORECASE)
 
     def __init__(self, version):
         # Validate the version and parse it into pieces
@@ -205,18 +224,11 @@ class Version(_BaseVersion):
         self._version = _Version(
             epoch=int(match.group("epoch")) if match.group("epoch") else 0,
             release=tuple(int(i) for i in match.group("release").split(".")),
-            pre=_parse_letter_version(
-                match.group("pre_l"),
-                match.group("pre_n"),
-            ),
+            pre=_parse_letter_version(match.group("pre_l"), match.group("pre_n")),
             post=_parse_letter_version(
-                match.group("post_l"),
-                match.group("post_n1") or match.group("post_n2"),
-            ),
-            dev=_parse_letter_version(
-                match.group("dev_l"),
-                match.group("dev_n"),
+                match.group("post_l"), match.group("post_n1") or match.group("post_n2")
             ),
+            dev=_parse_letter_version(match.group("dev_l"), match.group("dev_n")),
             local=_parse_local_version(match.group("local")),
         )
 
@@ -237,33 +249,58 @@ class Version(_BaseVersion):
         parts = []
 
         # Epoch
-        if self._version.epoch != 0:
-            parts.append("{0}!".format(self._version.epoch))
+        if self.epoch != 0:
+            parts.append("{0}!".format(self.epoch))
 
         # Release segment
-        parts.append(".".join(str(x) for x in self._version.release))
+        parts.append(".".join(str(x) for x in self.release))
 
         # Pre-release
-        if self._version.pre is not None:
-            parts.append("".join(str(x) for x in self._version.pre))
+        if self.pre is not None:
+            parts.append("".join(str(x) for x in self.pre))
 
         # Post-release
-        if self._version.post is not None:
-            parts.append(".post{0}".format(self._version.post[1]))
+        if self.post is not None:
+            parts.append(".post{0}".format(self.post))
 
         # Development release
-        if self._version.dev is not None:
-            parts.append(".dev{0}".format(self._version.dev[1]))
+        if self.dev is not None:
+            parts.append(".dev{0}".format(self.dev))
 
         # Local version segment
-        if self._version.local is not None:
-            parts.append(
-                "+{0}".format(".".join(str(x) for x in self._version.local))
-            )
+        if self.local is not None:
+            parts.append("+{0}".format(self.local))
 
         return "".join(parts)
 
     @property
+    def epoch(self):
+        return self._version.epoch
+
+    @property
+    def release(self):
+        return self._version.release
+
+    @property
+    def pre(self):
+        return self._version.pre
+
+    @property
+    def post(self):
+        return self._version.post[1] if self._version.post else None
+
+    @property
+    def dev(self):
+        return self._version.dev[1] if self._version.dev else None
+
+    @property
+    def local(self):
+        if self._version.local:
+            return ".".join(str(x) for x in self._version.local)
+        else:
+            return None
+
+    @property
     def public(self):
         return str(self).split("+", 1)[0]
 
@@ -272,27 +309,25 @@ class Version(_BaseVersion):
         parts = []
 
         # Epoch
-        if self._version.epoch != 0:
-            parts.append("{0}!".format(self._version.epoch))
+        if self.epoch != 0:
+            parts.append("{0}!".format(self.epoch))
 
         # Release segment
-        parts.append(".".join(str(x) for x in self._version.release))
+        parts.append(".".join(str(x) for x in self.release))
 
         return "".join(parts)
 
     @property
-    def local(self):
-        version_string = str(self)
-        if "+" in version_string:
-            return version_string.split("+", 1)[1]
-
-    @property
     def is_prerelease(self):
-        return bool(self._version.dev or self._version.pre)
+        return self.dev is not None or self.pre is not None
 
     @property
     def is_postrelease(self):
-        return bool(self._version.post)
+        return self.post is not None
+
+    @property
+    def is_devrelease(self):
+        return self.dev is not None
 
 
 def _parse_letter_version(letter, number):
@@ -326,7 +361,7 @@ def _parse_letter_version(letter, number):
         return letter, int(number)
 
 
-_local_version_seperators = re.compile(r"[\._-]")
+_local_version_separators = re.compile(r"[\._-]")
 
 
 def _parse_local_version(local):
@@ -336,7 +371,7 @@ def _parse_local_version(local):
     if local is not None:
         return tuple(
             part.lower() if not part.isdigit() else int(part)
-            for part in _local_version_seperators.split(local)
+            for part in _local_version_separators.split(local)
         )
 
 
@@ -347,12 +382,7 @@ def _cmpkey(epoch, release, pre, post, dev, local):
     # re-reverse it back into the correct order and make it a tuple and use
     # that for our sorting key.
     release = tuple(
-        reversed(list(
-            itertools.dropwhile(
-                lambda x: x == 0,
-                reversed(release),
-            )
-        ))
+        reversed(list(itertools.dropwhile(lambda x: x == 0, reversed(release))))
     )
 
     # We need to "trick" the sorting algorithm to put 1.0.dev0 before 1.0a0.
@@ -385,9 +415,6 @@ def _cmpkey(epoch, release, pre, post, dev, local):
         # - Numeric segments sort numerically
         # - Shorter versions sort before longer versions when the prefixes
         #   match exactly
-        local = tuple(
-            (i, "") if isinstance(i, int) else (-Infinity, i)
-            for i in local
-        )
+        local = tuple((i, "") if isinstance(i, int) else (-Infinity, i) for i in local)
 
     return epoch, release, pre, post, dev, local
diff --git a/setuptools/_vendor/vendored.txt b/setuptools/_vendor/vendored.txt
index 7d77863d..65183d9a 100644
--- a/setuptools/_vendor/vendored.txt
+++ b/setuptools/_vendor/vendored.txt
@@ -1,3 +1,4 @@
-packaging==16.8
+packaging==19.2
 pyparsing==2.2.1
 six==1.10.0
+ordered-set==3.1.1