platforms: rewrite mechanism which parses version into EVR

ssg/requirement_specs.py

@@ -11,91 +11,14 @@
 pkg_resources.safe_extra = lambda extra: re.sub('[^A-Za-z0-9.-]+', '_', extra).lower()
 
 
-def _add_version_element(elements, el):
-    elements.append(str(int(el)))
-
-
-def _add_version_elements_to_evr_component(evr, elements, component):
-    evr[component] = '.'.join(elements if elements else ['0'])
-    elements.clear()
-
-
-def _select_next_component(el):
-    if el.endswith('final-'):
-        return 'release'
-    if el.endswith('final'):
-        return None
-
-
-def _evr_from_tuple_for_sure(version_tuple):
-    # TODO: We do not support `epoch` at this moment, it is always None
-    evr = {'epoch': None, 'version': None, 'release': None}
-    component = 'version'
-    elements = []
-    for el in version_tuple:
-        if el.startswith('*'):
-            _add_version_elements_to_evr_component(evr, elements, component)
-            component = _select_next_component(el)
-            if component is None:
-                break
-            continue
-        _add_version_element(elements, el)
-    return evr
-
-
-def _evr_from_tuple(version_tuple):
-    # This is a version tuple from setuptools 0.9.8
-    # 1.22.33-444 -> ('00000011', '00000022', '00000033', '*final-', '00000444', '*final')
-    if isinstance(version_tuple, tuple):
-        return _evr_from_tuple_for_sure(version_tuple)
-    raise ValueError('Invalid object: %s, '
-                     'expected: tuple' % repr(version_tuple))
-
-
-def _evr_from_version_object_for_sure(version_object):
-    # TODO: We do not support `epoch` at this moment, it is always None
-    if hasattr(version_object, 'post'):
-        post = version_object.post
-    elif hasattr(version_object, '_version') and hasattr(version_object._version, 'post'):
-        # There was a range of versions around 40.8 of setuptools
-        # where `post` hasn't been a public property of the Version class.
-        # In _version it has structure of ('post', 12) for version 1.2.3-12.
-        post = version_object._version.post[1] if version_object._version.post else None
-    else:
-        raise ValueError('Invalid pkg_resources.packaging.version.Version object: '
-                         'no Version.post or Version._version.post attributes.'
-                         'Current version of setuptools is not supported.')
-    return {'epoch': None,
-            'version': version_object.base_version,
-            'release': str(post) if post else None}
-
-
-def _evr_from_version_object(version_object):
-    if isinstance(version_object, pkg_resources.packaging.version.Version):
-        return _evr_from_version_object_for_sure(version_object)
-    raise ValueError('Invalid version object: %s, '
-                     'expected: pkg_resources.packaging.version.Version' % repr(version_object))
-
-
-def _get_evr(version_something):
-    # Function should be redefined in accordance with setuptools behaviour. See below.
-    raise Exception("No EVR parser defined!")
-
-
-try:
-    from pkg_resources import packaging
-    # We are using modern setuptools, packaging.version.Version is available
-    # and is used as the result of parse_version() function.
-    _get_evr = _evr_from_version_object
-except ImportError:
-    # We are using old setuptools (Python 2.7 / 0.9.8) the parse_version() function
-    # returns a tuple object.
-    _get_evr = _evr_from_tuple
-
-
 def _parse_version_into_evr(version):
-    ver = pkg_resources.parse_version(version)
-    return _get_evr(ver)
+    evr = {"epoch": None, "version": None, "release": None}
+    match_version = re.match(r'^(\d[\d\.]*)(?:-(\d*))?$', version)
+    if not match_version:
+        raise ValueError("Invalid version specifier {0}".format(version))
+    evr["version"] = match_version.groups()[0]
+    evr["release"] = match_version.groups()[1]
+    return evr
 
 
 def _spec_to_version_specifier(spec):

tests/unit/ssg-module/test_requirement_specs.py

@@ -3,20 +3,6 @@
 from ssg import requirement_specs
 
 
-def test_evr_from_tuple():
-    v = requirement_specs._evr_from_tuple(
-        ('00000001', '00000022', '00000333', '*final-', '00004444', '*final'))
-    assert v == {'epoch': None, 'version': '1.22.333', 'release': '4444'}
-
-    v = requirement_specs._evr_from_tuple(
-        ('*final',))
-    assert v == {'epoch': None, 'version': '0', 'release': None}
-
-    v = requirement_specs._evr_from_tuple(
-        ('*final-', '00000001', '*final'))
-    assert v == {'epoch': None, 'version': '0', 'release': '1'}
-
-
 def test_parse_version_into_evr():
     v = requirement_specs._parse_version_into_evr('1.22.333-4444')
     assert v == {'epoch': None, 'version': '1.22.333', 'release': '4444'}
@@ -34,3 +20,20 @@ def test_parse_version_into_evr():
     # We do not support epoch at this moment, this version string is invalid.
     with pytest.raises(ValueError):
         v = requirement_specs._parse_version_into_evr('1:1.0.0')
+
+    # we do not support letters anywhere for now
+
+    with pytest.raises(ValueError):
+        v = requirement_specs._parse_version_into_evr('1.0.0-r2')
+    with pytest.raises(ValueError):
+        v = requirement_specs._parse_version_into_evr('b1')
+
+    # some more tests to ensure that the regex is correct
+    with pytest.raises(ValueError):
+        v = requirement_specs._parse_version_into_evr('0:')
+    with pytest.raises(ValueError):
+        v = requirement_specs._parse_version_into_evr('-1')
+    with pytest.raises(ValueError):
+        v = requirement_specs._parse_version_into_evr(':')
+    with pytest.raises(ValueError):
+        v = requirement_specs._parse_version_into_evr('-')