Forbid build metadata ordering (See #18)

SemVer 2.0.0 states that "Build metadata SHOULD be ignored when
determining version precedence".

This means that, when comparing ``0.1.0+1`` to ``0.1.0+bcd``::

    >>> Version('0.1.0+1') == Version('0.1.0+bcd')
    False
    >>> Version('0.1.0+1') != Version('0.1.0+bcd')
    True
    >>> Version('0.1.0+1') < Version('0.1.0+bcd')
    False
    >>> Version('0.1.0+1') > Version('0.1.0+bcd')
    False
    >>> Version('0.1.0+1') <= Version('0.1.0+bcd')
    False
    >>> Version('0.1.0+1') >= Version('0.1.0+bcd')
    False
    >>> compare(Version('0.1.0+1'), Version('0.1.0+bcd'))
    NotImplemented

This change also has the following effects:
- When including build metadata in a ``Spec``, the only valid options
  are ``Spec('==0.1.0+sth')`` and ``Spec('!=0.1.0+sth')``
- The meaning of ``Spec('==0.1.0+')`` is now "Only version 0.1.0 without
  build metadata"
- ``Spec('==0.1.0')`` now matches ``Version('0.1.0+anything')``

9 files changed, 192 insertions, 113 deletions

diff --git a/ChangeLog b/ChangeLog
index fac48ca..cd7c3db 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,6 +1,36 @@
 ChangeLog
 =========
 
+2.5.0 (master)
+--------------
+
+*Bugfix:*
+
+    `#18 <https://github.com/rbarrois/python-semanticversion/issues/18>`_: According to SemVer 2.0.0, build numbers aren't ordered.
+
+    * Remove specs of the ``Spec('<1.1.3+')`` form
+    * Comparing ``Version('0.1.0')`` to ``Version('0.1.0+bcd')`` has new
+      rules::
+
+          >>> Version('0.1.0+1') == Version('0.1.0+bcd')
+          False
+          >>> Version('0.1.0+1') != Version('0.1.0+bcd')
+          True
+          >>> Version('0.1.0+1') < Version('0.1.0+bcd')
+          False
+          >>> Version('0.1.0+1') > Version('0.1.0+bcd')
+          False
+          >>> Version('0.1.0+1') <= Version('0.1.0+bcd')
+          False
+          >>> Version('0.1.0+1') >= Version('0.1.0+bcd')
+          False
+          >>> compare(Version('0.1.0+1'), Version('0.1.0+bcd'))
+          NotImplemented
+
+    * :func:`semantic_version.compare` returns ``NotImplemented`` when its
+      parameters differ only by build metadata
+    * ``Spec('<=1.3.0')`` now matches ``Version('1.3.0+abde24fe883')``
+
 2.4.2 (2015-07-02)
 ------------------
 
diff --git a/README.rst b/README.rst
index 5923a30..484692e 100644
--- a/README.rst
+++ b/README.rst
@@ -247,19 +247,18 @@ definition or (for the empty pre-release number) if a single dash is appended
     False
 
 
-Including build identifiers in specifications
-"""""""""""""""""""""""""""""""""""""""""""""
+Including build metadata in specifications
+""""""""""""""""""""""""""""""""""""""""""
 
-The same rule applies for the build identifier: comparisons will include it only
-if it was included in the :class:`Spec` definition, or - for the unnumbered build
-version - if a single + is appended to the definition(``1.0.0+``, ``1.0.0-alpha+``):
+Build metadata has no ordering; thus, the only meaningful comparison including
+build metadata is equality.
 
 
 .. code-block:: pycon
 
-    >>> Version('1.0.0+build2') in Spec('<=1.0.0')   # Build identifier ignored
+    >>> Version('1.0.0+build2') in Spec('<=1.0.0')   # Build metadata ignored
     True
-    >>> Version('1.0.0+build2') in Spec('<=1.0.0+')  # Include build in checks
+    >>> Version('1.0.0+build2') in Spec('==1.0.0+build2')  # Include build in checks
     False
 
 
diff --git a/docs/reference.rst b/docs/reference.rst
index 3550c25..261e738 100644
--- a/docs/reference.rst
+++ b/docs/reference.rst
@@ -22,9 +22,13 @@ Module-level functions
     :param str v1: The first version to compare
     :param str v2: The second version to compare
     :raises: :exc:`ValueError`, if any version string is invalid
-    :rtype: ``int``, -1 / 0 / 1 as for a :func:`cmp` comparison
+    :rtype: ``int``, -1 / 0 / 1 as for a :func:`cmp` comparison;
+            ``NotImplemented`` if versions only differ by build metadata
 
 
+.. warning:: Since build metadata has no ordering,
+             ``compare(Version('0.1.1'), Version('0.1.1+3'))`` returns ``NotImplemented``
+
 
 .. function:: match(spec, version)
 
@@ -107,9 +111,9 @@ Representing a version (the Version class)
 
     .. attribute:: build
 
-        ``tuple`` of ``strings``, the build component.
+        ``tuple`` of ``strings``, the build metadata.
 
-        It contains the various dot-separated identifiers in the build component.
+        It contains the various dot-separated identifiers in the build metadata.
 
         May be ``None`` for a :attr:`partial` version number in a ``<major>``, ``<major>.<minor>``,
         ``<major>.<minor>.<patch>`` or ``<major>.<minor>.<patch>-<prerelease>`` format.
@@ -151,7 +155,7 @@ Representing a version (the Version class)
             For instance, ``Version('1.0', partial=True)`` means "any version beginning in ``1.0``".
 
             ``Version('1.0.1-alpha', partial=True)`` means "The ``1.0.1-alpha`` version or any
-            ulterior build of that same version": ``1.0.1-alpha+build3`` matches, ``1.0.1-alpha.2`` doesn't.
+            any release differing only in build metadata": ``1.0.1-alpha+build3`` matches, ``1.0.1-alpha.2`` doesn't.
 
         Examples::
 
@@ -246,7 +250,6 @@ The main issue with representing version specifications is that the usual syntax
 does not map well onto `SemVer`_ precedence rules:
 
 * A specification of ``<1.3.4`` is not expected to allow ``1.3.4-rc2``, but strict `SemVer`_ comparisons allow it ;
-* Converting the previous specification to ``<=1.3.3`` in order to avoid ``1.3.4``
   prereleases has the issue of excluding ``1.3.3+build3`` ;
 * It may be necessary to exclude either all variations on a patch-level release
   (``!=1.3.3``) or specifically one build-level release (``1.3.3-build.434``).
@@ -256,7 +259,7 @@ In order to have version specification behave naturally, the rules are the follo
 
 * If no pre-release number was included in the specification, pre-release numbers
   are ignored when deciding whether a version satisfies a specification.
-* If no build number was included in the specification, build numbers are ignored
+* If no build metadata was included in the specification, build metadata is ignored
   when deciding whether a version satisfies a specification.
 
 This means that::
@@ -267,7 +270,7 @@ This means that::
     True
     >>> Version('1.1.1-rc1+build4') in Spec('<=1.1.1-rc1')
     True
-    >>> Version('1.1.1-rc1+build4') in Spec('<=1.1.1-rc1+build2')
+    >>> Version('1.1.1-rc1+build4') in Spec('==1.1.1-rc1+build2')
     False
 
 
@@ -285,20 +288,31 @@ rules apply:
     >>> Version('1.1.1-rc1') in Spec('<1.1.1-')
     True
 
-* Setting a build separator without a build identifier (``>1.1.1+``) forces
-  satisfaction tests to include both prerelease and build identifiers::
+* Setting a build metadata separator without build metadata (``<=1.1.1+``)
+  forces matches "up to the build metadata"; use this to include/exclude a
+  release lacking build metadata while excluding/including all other builds
+  of that release
 
-    >>> Version('1.1.1+build2') in Spec('>1.1.1')
-    False
-    >>> Version('1.1.1+build2') in Spec('>1.1.1+')
+    >>> Version('1.1.1') in Spec('==1.1.1+')
     True
+    >>> Version('1.1.1+2') in Spec('==1.1.1+')
+    False
+
+
+.. warning:: As stated in the `SemVer`_ specification, the ordering of build metadata is *undefined*.
+             Thus, a :class:`Spec` string can only mention build metadata to include or exclude a specific version:
+
+             * ``==1.1.1+b1234`` includes this specific build
+             * ``!=1.1.1+b1234`` excludes it (but would match ``1.1.1+b1235``
+             * ``<1.1.1+b1`` is invalid
+
 
 .. class:: Spec(spec_string[, spec_string[, ...]])
 
     Stores a list of :class:`SpecItem` and matches any :class:`Version` against all
     contained :class:`specs <SpecItem>`.
 
-    It is build from a comma-separated list of version specifications::
+    It is built from a comma-separated list of version specifications::
 
         >>> Spec('>=1.0.0,<1.2.0,!=1.1.4')
         <Spec: (
@@ -427,16 +441,16 @@ rules apply:
 
         >>> SpecItem('>=0.1.1').match(Version('0.1.1-rc1'))  # pre-release satisfy conditions
         True
-        >>> Version('0.1.1+build2') in SpecItem('>=0.1.1')   # build version satisfy specifications
+        >>> Version('0.1.1+build2') in SpecItem('>=0.1.1')   # build metadata is ignored when checking for precedence
         True
         >>>
         >>> # Use the '-' marker to include the pre-release component in checks
         >>> SpecItem('>=0.1.1-').match(Version('0.1.1-rc1')
         False
-        >>>
-        >>> # Use the '+' marker to include the build identifier in checks
-        >>> SpecItem('<=0.1.1-alpha+').match(Version('0.1.1-alpha+build1'))
+        >>> # Use the '+' marker to include the build metadata in checks
+        >>> SpecItem('==0.1.1+').match(Version('0.1.1+b1234')
         False
+        >>>
 
 
     .. rubric:: Attributes
diff --git a/semantic_version/base.py b/semantic_version/base.py
index 841c5f3..982fcc8 100644
--- a/semantic_version/base.py
+++ b/semantic_version/base.py
@@ -290,20 +290,14 @@ class Version(object):
                 return 0
 
         def build_cmp(a, b):
-            """Compare build components.
+            """Compare build metadata.
 
-            Special rule: a version without build component has lower
-            precedence than one with a build component.
+            Special rule: there is no ordering on build metadata.
             """
-            if a and b:
-                return identifier_list_cmp(a, b)
-            elif a:
-                # Versions with build field have higher precedence
-                return 1
-            elif b:
-                return -1
-            else:
+            if a == b:
                 return 0
+            else:
+                return NotImplemented
 
         def make_optional(orig_cmp_fun):
             """Convert a cmp-like function to consider 'None == *'."""
@@ -332,10 +326,7 @@ class Version(object):
                 build_cmp,
             ]
 
-    def __cmp__(self, other):
-        if not isinstance(other, self.__class__):
-            return NotImplemented
-
+    def __compare(self, other):
         field_pairs = zip(self, other)
         comparison_functions = self._comparison_functions(partial=self.partial or other.partial)
         comparisons = zip(comparison_functions, self, other)
@@ -347,44 +338,48 @@ class Version(object):
 
         return 0
 
-    def __eq__(self, other):
-        if not isinstance(other, self.__class__):
-            return NotImplemented
-
-        return self.__cmp__(other) == 0
-
     def __hash__(self):
         return hash((self.major, self.minor, self.patch, self.prerelease, self.build))
 
-    def __ne__(self, other):
+    def __cmp__(self, other):
         if not isinstance(other, self.__class__):
             return NotImplemented
+        return self.__compare(other)
 
-        return self.__cmp__(other) != 0
+    def __compare_helper(self, other, condition, notimpl_target):
+        """Helper for comparison.
 
-    def __lt__(self, other):
+        Allows the caller to provide:
+        - The condition
+        - The return value if the comparison is meaningless (ie versions with
+            build metadata).
+        """
         if not isinstance(other, self.__class__):
             return NotImplemented
 
-        return self.__cmp__(other) < 0
+        cmp_res = self.__cmp__(other)
+        if cmp_res is NotImplemented:
+            return notimpl_target
 
-    def __le__(self, other):
-        if not isinstance(other, self.__class__):
-            return NotImplemented
+        return condition(cmp_res)
 
-        return self.__cmp__(other) <= 0
+    def __eq__(self, other):
+        return self.__compare_helper(other, lambda x: x == 0, notimpl_target=False)
 
-    def __gt__(self, other):
-        if not isinstance(other, self.__class__):
-            return NotImplemented
+    def __ne__(self, other):
+        return self.__compare_helper(other, lambda x: x != 0, notimpl_target=True)
 
-        return self.__cmp__(other) > 0
+    def __lt__(self, other):
+        return self.__compare_helper(other, lambda x: x < 0, notimpl_target=False)
 
-    def __ge__(self, other):
-        if not isinstance(other, self.__class__):
-            return NotImplemented
+    def __le__(self, other):
+        return self.__compare_helper(other, lambda x: x <= 0, notimpl_target=False)
+
+    def __gt__(self, other):
+        return self.__compare_helper(other, lambda x: x > 0, notimpl_target=False)
 
-        return self.__cmp__(other) >= 0
+    def __ge__(self, other):
+        return self.__compare_helper(other, lambda x: x >= 0, notimpl_target=False)
 
 
 class SpecItem(object):
@@ -420,6 +415,10 @@ class SpecItem(object):
 
         kind, version = match.groups()
         spec = Version(version, partial=True)
+        if spec.build is not None and kind not in (cls.KIND_EQUAL, cls.KIND_NEQ):
+            raise ValueError(
+                    "Invalid requirement specification %r: build numbers have no ordering."
+                    % requirement_string)
         return (kind, spec)
 
     def match(self, version):
diff --git a/semantic_version/compat.py b/semantic_version/compat.py
index bea6f67..4dd60fe 100644
--- a/semantic_version/compat.py
+++ b/semantic_version/compat.py
@@ -2,17 +2,14 @@
 # Copyright (c) 2012-2014 The python-semanticversion project
 # This code is distributed under the two-clause BSD License.
 
-import sys
 
-is_python2 = (sys.version_info[0] == 2)
-
-if is_python2:  # pragma: no cover
-    base_cmp = cmp
-else:  # pragma: no cover
-    def base_cmp(x, y):
-        if x < y:
-            return -1
-        elif x > y:
-            return 1
-        else:
-            return 0
+def base_cmp(x, y):
+    if x == y:
+        return 0
+    elif x > y:
+        return 1
+    elif x < y:
+        return -1
+    else:
+        # Fix Py2's behavior: cmp(x, y) returns -1 for unorderable types
+        return NotImplemented
diff --git a/tests/test_base.py b/tests/test_base.py
index df5d4ee..ae23d86 100755
--- a/tests/test_base.py
+++ b/tests/test_base.py
@@ -64,7 +64,7 @@ class TopLevelTestCase(unittest.TestCase):
         ('0.1.1', '0.1.1', 0),
         ('0.1.1', '0.1.0', 1),
         ('0.1.0-alpha', '0.1.0', -1),
-        ('0.1.0-alpha+2', '0.1.0-alpha', 1),
+        ('0.1.0-alpha+2', '0.1.0-alpha', NotImplemented),
     )
 
     def test_compare(self):
@@ -179,7 +179,6 @@ class VersionTestCase(unittest.TestCase):
         '1.1.2': (1, 1, 2, None, None),
         '1.1.3-rc4.5': (1, 1, 3, ('rc4', '5'), None),
         '1.0.0-': (1, 0, 0, (), None),
-        '1.0.0+': (1, 0, 0, (), ()),
         '1.0.0-rc.1+build.1': (1, 0, 0, ('rc', '1'), ('build', '1')),
         '1.0.0+0.3.7': (1, 0, 0, (), ('0', '3', '7')),
         '1.3.7+build': (1, 3, 7, (), ('build',)),
@@ -272,18 +271,29 @@ class VersionTestCase(unittest.TestCase):
 
 
 class SpecItemTestCase(unittest.TestCase):
+    invalids = [
+        '<=0.1.1+build3',
+        '<=0.1.1+',
+        '>0.2.3-rc2+',
+    ]
+
+    def test_invalids(self):
+        for invalid in self.invalids:
+            with self.assertRaises(ValueError, msg="SpecItem(%r) should be invalid" % invalid):
+                _v = base.SpecItem(invalid)
+
     components = {
         '==0.1.0': (base.SpecItem.KIND_EQUAL, 0, 1, 0, None, None),
         '==0.1.2-rc3': (base.SpecItem.KIND_EQUAL, 0, 1, 2, ('rc3',), None),
         '==0.1.2+build3.14': (base.SpecItem.KIND_EQUAL, 0, 1, 2, (), ('build3', '14')),
-        '<=0.1.1+': (base.SpecItem.KIND_LTE, 0, 1, 1, (), ()),
+        '<=0.1.1': (base.SpecItem.KIND_LTE, 0, 1, 1, None, None),
         '<0.1.1': (base.SpecItem.KIND_LT, 0, 1, 1, None, None),
         '<=0.1.1': (base.SpecItem.KIND_LTE, 0, 1, 1, None, None),
+        '!=0.1.1+': (base.SpecItem.KIND_NEQ, 0, 1, 1, (), ()),
         '<=0.1.1-': (base.SpecItem.KIND_LTE, 0, 1, 1, (), None),
         '>=0.2.3-rc2': (base.SpecItem.KIND_GTE, 0, 2, 3, ('rc2',), None),
-        '>0.2.3-rc2+': (base.SpecItem.KIND_GT, 0, 2, 3, ('rc2',), ()),
         '>=2.0.0': (base.SpecItem.KIND_GTE, 2, 0, 0, None, None),
-        '!=0.1.1+': (base.SpecItem.KIND_NEQ, 0, 1, 1, (), ()),
+        '!=0.1.1+rc3': (base.SpecItem.KIND_NEQ, 0, 1, 1, (), ('rc3',)),
         '!=0.3.0': (base.SpecItem.KIND_NEQ, 0, 3, 0, None, None),
     }
 
@@ -335,13 +345,17 @@ class SpecItemTestCase(unittest.TestCase):
             ['0.2.3-rc3', '0.2.3', '0.2.3+1', '0.2.3-rc2', '0.2.3-rc2+1'],
             ['0.2.3-rc1', '0.2.2'],
         ),
-        '>0.2.3-rc2+': (
-            ['0.2.3-rc3', '0.2.3', '0.2.3-rc2+1'],
-            ['0.2.3-rc1', '0.2.2', '0.2.3-rc2'],
+        '==0.2.3+': (
+            ['0.2.3'],
+            ['0.2.3+rc1', '0.2.4', '0.2.3-rc2'],
+        ),
+        '!=0.2.3-rc2+12': (
+            ['0.2.3-rc3', '0.2.3', '0.2.3-rc2+1', '0.2.4', '0.2.3-rc3+12'],
+            ['0.2.3-rc2+12'],
         ),
-        '>2.0.0+': (
-            ['2.1.1', '2.0.0+b1', '3.1.4'],
-            ['1.9.9', '1.9.9999', '2.0.0', '2.0.0-rc4'],
+        '==2.0.0+b1': (
+            ['2.0.0+b1'],
+            ['2.1.1', '1.9.9', '1.9.9999', '2.0.0', '2.0.0-rc4'],
         ),
         '!=0.1.1': (
             ['0.1.2', '0.1.0', '1.4.2'],
@@ -440,13 +454,17 @@ class SpecTestCase(unittest.TestCase):
                 self.assertTrue(repr(base.SpecItem(spec_text)) in repr(spec_list))
 
     matches = {
+        # At least 0.1.1 including pre-releases, less than 0.1.2 excluding pre-releases
         '>=0.1.1,<0.1.2': (
             ['0.1.1', '0.1.1+4', '0.1.1-alpha'],
             ['0.1.2-alpha', '0.1.2', '1.3.4'],
         ),
-        '>=0.1.0+,!=0.1.3-rc1,<0.1.4': (
+        # At least 0.1.0 without pre-releases, less than 0.1.4 excluding pre-releases,
+        # neither 0.1.3-rc1 nor any build of that version,
+        # not 0.1.0+b3 precisely
+        '>=0.1.0-,!=0.1.3-rc1,!=0.1.0+b3,<0.1.4': (
             ['0.1.1', '0.1.0+b4', '0.1.2', '0.1.3-rc2'],
-            ['0.0.1', '0.1.4', '0.1.4-alpha', '0.1.3-rc1+4',
+            ['0.0.1', '0.1.0+b3', '0.1.4', '0.1.4-alpha', '0.1.3-rc1+4',
              '0.1.0-alpha', '0.2.2', '0.1.4-rc1'],
         ),
     }
diff --git a/tests/test_match.py b/tests/test_match.py
index 155a612..6926e0a 100755
--- a/tests/test_match.py
+++ b/tests/test_match.py
@@ -15,6 +15,7 @@ class MatchTestCase(unittest.TestCase):
         '<=0.1.4a',
         '>0.1.1.1',
         '~0.1.2-rc23,1',
+        '<0.1.2-rc1.3-14.15+build.2012-01-01.11h34',
     ]
 
     valid_specs = [
@@ -25,7 +26,7 @@ class MatchTestCase(unittest.TestCase):
         '>0.1.2-rc1',
         '>=0.1.2-rc1.3.4',
         '==0.1.2+build42-12.2012-01-01.12h23',
-        '<0.1.2-rc1.3-14.15+build.2012-01-01.11h34',
+        '!=0.1.2-rc1.3-14.15+build.2012-01-01.11h34',
     ]
 
     matches = {
@@ -53,11 +54,19 @@ class MatchTestCase(unittest.TestCase):
             '0.1.2',
             '0.1.2+build4',
         ],
-        '<0.1.2+': [
+        '!=0.1.2+': [
+            '0.1.2+1',
+            '0.1.2-rc1',
+        ],
+        '!=0.1.2-': [
             '0.1.1',
             '0.1.2-rc1',
-            '0.1.2-rc1.3.4',
-            '0.1.2-rc1+build4.5',
+        ],
+        '!=0.1.2+345': [
+            '0.1.1',
+            '0.1.2-rc1+345',
+            '0.1.2+346',
+            '0.2.3+345',
         ],
         '>=0.1.1': [
             '0.1.1',
@@ -72,12 +81,6 @@ class MatchTestCase(unittest.TestCase):
             '0.2.0',
             '1.0.0',
         ],
-        '>0.1.1+': [
-            '0.1.1+b2',
-            '0.1.2-rc1',
-            '1.1.1',
-            '2.0.4',
-        ],
         '<0.1.1-': [
             '0.1.1-alpha',
             '0.1.1-rc4',
@@ -87,7 +90,8 @@ class MatchTestCase(unittest.TestCase):
 
     def test_invalid(self):
         for invalid in self.invalid_specs:
-            self.assertRaises(ValueError, semantic_version.Spec, invalid)
+            with self.assertRaises(ValueError, msg="Spec(%r) should be invalid" % invalid):
+                semantic_version.Spec(invalid)
 
     def test_simple(self):
         for valid in self.valid_specs:
@@ -122,11 +126,9 @@ class MatchTestCase(unittest.TestCase):
         self.assertFalse(version in strict_spec, "%r should not be in %r" % (version, strict_spec))
 
     def test_build_check(self):
-        strict_spec = semantic_version.Spec('<=0.1.1-rc1+')
-        lax_spec = semantic_version.Spec('<=0.1.1-rc1')
+        spec = semantic_version.Spec('<=0.1.1-rc1')
         version = semantic_version.Version('0.1.1-rc1+4.2')
-        self.assertTrue(version in lax_spec, "%r should be in %r" % (version, lax_spec))
-        self.assertFalse(version in strict_spec, "%r should not be in %r" % (version, strict_spec))
+        self.assertTrue(version in spec, "%r should be in %r" % (version, spec))
 
 
 if __name__ == '__main__':  # pragma: no cover
diff --git a/tests/test_parsing.py b/tests/test_parsing.py
index 5112ca5..c7651d2 100755
--- a/tests/test_parsing.py
+++ b/tests/test_parsing.py
@@ -3,6 +3,7 @@
 # Copyright (c) 2012-2014 The python-semanticversion project
 # This code is distributed under the two-clause BSD License.
 
+import itertools
 import unittest
 
 import semantic_version
@@ -44,12 +45,8 @@ class ComparisonTestCase(unittest.TestCase):
         '1.0.0-beta.2',
         '1.0.0-beta.11',
         '1.0.0-rc.1',
-        '1.0.0-rc.1+build.1',
         '1.0.0',
-        '1.0.0+0.3.7',
         '1.3.7+build',
-        '1.3.7+build.2.b8f12d7',
-        '1.3.7+build.11.e0f985a',
     ]
 
     def test_comparisons(self):
@@ -67,6 +64,36 @@ class ComparisonTestCase(unittest.TestCase):
                 cmp_res = -1 if i < j else (1 if i > j else 0)
                 self.assertEqual(cmp_res, semantic_version.compare(first, second))
 
+    unordered = [
+        [
+            '1.0.0-rc.1',
+            '1.0.0-rc.1+build.1',
+        ],
+        [
+            '1.0.0',
+            '1.0.0+0.3.7',
+        ],
+        [
+            '1.3.7',
+            '1.3.7+build',
+            '1.3.7+build.2.b8f12d7',
+            '1.3.7+build.11.e0f985a',
+        ],
+    ]
+
+    def test_unordered(self):
+        for group in self.unordered:
+            for a, b in itertools.combinations(group, 2):
+                v1 = semantic_version.Version(a)
+                v2 = semantic_version.Version(b)
+                self.assertTrue(v1 == v1, "%r != %r" % (v1, v1))
+                self.assertFalse(v1 != v1, "%r != %r" % (v1, v1))
+                self.assertFalse(v1 == v2, "%r == %r" % (v1, v2))
+                self.assertTrue(v1 != v2, "%r !!= %r" % (v1, v2))
+                self.assertFalse(v1 < v2, "%r !< %r" % (v1, v2))
+                self.assertFalse(v1 <= v2, "%r !<= %r" % (v1, v2))
+                self.assertFalse(v2 > v1, "%r !> %r" % (v2, v1))
+                self.assertFalse(v2 >= v1, "%r !>= %r" % (v2, v1))
 
 if __name__ == '__main__':  # pragma: no cover
     unittest.main()
diff --git a/tests/test_spec.py b/tests/test_spec.py
index 7a645f9..a13cb0b 100644
--- a/tests/test_spec.py
+++ b/tests/test_spec.py
@@ -154,10 +154,3 @@ class FormatTests(unittest.TestCase):
         self.assertLess(Version('1.0.0-beta.2'), Version('1.0.0-beta.11'))
         self.assertLess(Version('1.0.0-beta.11'), Version('1.0.0-rc.1'))
         self.assertLess(Version('1.0.0-rc.1'), Version('1.0.0'))
-
-
-
-class PrecedenceTestCase(unittest.TestCase):
-    pass
-
-