make LooseVersion('1.0') == LooseVersion('1')

Remove the pitfall where missing components were filled with
empty strings that are less than any other value.
The common expectation is that trailing zeroes are equal to zeroes.
If the trailing part is a string the current behavior is kept.

Author: Flamefire

easybuild/tools/loose_version.py

@@ -77,17 +77,19 @@ def _cmp(self, other):
         if isinstance(other, str):
             other = LooseVersion(other)
 
-        # Modified: Behave the same in Python 2 & 3 when parts are of different types
-        # Taken from https://bugs.python.org/issue14894
-        for i, j in zip_longest(self.version, other.version, fillvalue=''):
-            if not type(i) is type(j):
+        # Modified: Use string comparison for different types and fill with zeroes/empty strings
+        # Based on https://bugs.python.org/issue14894
+        for i, j in zip_longest(self.version, other.version):
+            if i is None:
+                i = 0 if isinstance(j, int) else ''
+            elif j is None:
+                j = 0 if isinstance(i, int) else ''
+            elif not type(i) is type(j):
                 i = str(i)
                 j = str(j)
-            if i == j:
-                continue
-            elif i < j:
+            if i < j:
                 return -1
-            else:  # i > j
+            if i > j:
                 return 1
         return 0
 

test/framework/utilities_test.py

@@ -140,15 +140,19 @@ def test_LooseVersion(self):
         self.assertLess(LooseVersion('2.1.5'), LooseVersion('2.2'))
         self.assertLess(LooseVersion('2.1.3'), LooseVersion('3'))
         self.assertLessEqual(LooseVersion('2.1.0'), LooseVersion('2.2'))
-        # Careful here: 1.0 > 1 !!!
-        self.assertGreater(LooseVersion('1.0'), LooseVersion('1'))
-        self.assertLess(LooseVersion('1'), LooseVersion('1.0'))
+        # Missing components are either empty strings or zeroes
+        self.assertEqual(LooseVersion('1.0'), LooseVersion('1'))
+        self.assertEqual(LooseVersion('1'), LooseVersion('1.0'))
+        self.assertEqual(LooseVersion('1.0'), LooseVersion('1.'))
+        self.assertGreater(LooseVersion('2.1.a'), LooseVersion('2.1'))
+        self.assertGreater(LooseVersion('2.a'), LooseVersion('2'))
+
         # checking prereleases
         self.assertGreater(LooseVersion('4.0.0-beta'), LooseVersion('4.0.0'))
-        self.assertEqual(LooseVersion('4.0.0-beta').is_prerelease('4.0.0', ['-beta']), True)
-        self.assertEqual(LooseVersion('4.0.0-beta').is_prerelease('4.0.0', ['rc']), False)
+        self.assertTrue(LooseVersion('4.0.0-beta').is_prerelease('4.0.0', ['-beta']))
+        self.assertFalse(LooseVersion('4.0.0-beta').is_prerelease('4.0.0', ['rc']))
 
-        # The following test is taken from Python distutils tests
+        # The following test is based on the Python distutils tests
         # licensed under the Python Software Foundation License Version 2
         versions = (('1.5.1', '1.5.2b2', -1),
                     ('161', '3.10a', 1),
@@ -158,16 +162,21 @@ def test_LooseVersion(self):
                     ('2g6', '11g', -1),
                     ('0.960923', '2.2beta29', -1),
                     ('1.13++', '5.5.kw', -1),
-                    # Added from https://bugs.python.org/issue14894
                     ('a.12.b.c', 'a.b.3', -1),
-                    ('1.0', '1', 1),
-                    ('1', '1.0', -1))
+                    ('1.0', '1', 0),
+                    ('1.a', '1', 1),
+                    )
 
         for v1, v2, wanted in versions:
             res = LooseVersion(v1)._cmp(LooseVersion(v2))
             self.assertEqual(res, wanted,
                              'cmp(%s, %s) should be %s, got %s' %
                              (v1, v2, wanted, res))
+            # Test the inverse
+            res = LooseVersion(v2)._cmp(LooseVersion(v1))
+            self.assertEqual(res, -wanted,
+                             'cmp(%s, %s) should be %s, got %s' %
+                             (v2, v1, -wanted, res))
             # vstring is the unparsed version
             self.assertEqual(LooseVersion(v1).vstring, v1)