euscan: don't import pkg_resources, we don't want all these warnings

Signed-off-by: Corentin Chary <corentin.chary@gmail.com>

pym/euscan/helpers.py

@@ -1,8 +1,6 @@
 import os
 import re
-import pkg_resources
 import errno
-
 import urllib2
 
 import portage
@@ -15,10 +13,9 @@ except ImportError:
     import robotparser
     import urlparse
 
-
-from euscan import CONFIG, BLACKLIST_VERSIONS, ROBOTS_TXT_BLACKLIST_DOMAINS
 import euscan
-
+from euscan import CONFIG, BLACKLIST_VERSIONS, ROBOTS_TXT_BLACKLIST_DOMAINS
+from euscan.version import parse_version
 
 def htop_vercmp(a, b):
     def fixver(v):
@@ -182,8 +179,8 @@ def simple_vercmp(a, b):
         return r
 
     # Fallback
-    a = pkg_resources.parse_version(a)
-    b = pkg_resources.parse_version(b)
+    a = pkg_parse_version(a)
+    b = pkg_parse_version(b)
 
     if a < b:
         return -1
@@ -198,8 +195,8 @@ def vercmp(package, a, b):
 
 
 def version_is_nightly(a, b):
-    a = pkg_resources.parse_version(a)
-    b = pkg_resources.parse_version(b)
+    a = parse_version(a)
+    b = parse_version(b)
 
     ''' Try to skip nightly builds when not wanted (www-apps/moodle) '''
     if len(a) != len(b) and len(b) == 2 and len(b[0]) == len('yyyymmdd'):

pym/euscan/version.py

@@ -0,0 +1,60 @@
+import re
+
+# Stolen from pkg_resources, but importing it is not a good idea
+
+component_re = re.compile(r'(\d+ | [a-z]+ | \.| -)', re.VERBOSE)
+replace = {'pre':'c', 'preview':'c','-':'final-','rc':'c','dev':'@'}.get
+
+def _parse_version_parts(s):
+    for part in component_re.split(s):
+        part = replace(part,part)
+        if not part or part=='.':
+            continue
+        if part[:1] in '0123456789':
+            yield part.zfill(8)    # pad for numeric comparison
+        else:
+            yield '*'+part
+
+    yield '*final'  # ensure that alpha/beta/candidate are before final
+
+def parse_version(s):
+    """Convert a version string to a chronologically-sortable key
+
+    This is a rough cross between distutils' StrictVersion and LooseVersion;
+    if you give it versions that would work with StrictVersion, then it behaves
+    the same; otherwise it acts like a slightly-smarter LooseVersion. It is
+    *possible* to create pathological version coding schemes that will fool
+    this parser, but they should be very rare in practice.
+
+    The returned value will be a tuple of strings.  Numeric portions of the
+    version are padded to 8 digits so they will compare numerically, but
+    without relying on how numbers compare relative to strings.  Dots are
+    dropped, but dashes are retained.  Trailing zeros between alpha segments
+    or dashes are suppressed, so that e.g. "2.4.0" is considered the same as
+    "2.4". Alphanumeric parts are lower-cased.
+
+    The algorithm assumes that strings like "-" and any alpha string that
+    alphabetically follows "final"  represents a "patch level".  So, "2.4-1"
+    is assumed to be a branch or patch of "2.4", and therefore "2.4.1" is
+    considered newer than "2.4-1", which in turn is newer than "2.4".
+
+    Strings like "a", "b", "c", "alpha", "beta", "candidate" and so on (that
+    come before "final" alphabetically) are assumed to be pre-release versions,
+    so that the version "2.4" is considered newer than "2.4a1".
+
+    Finally, to handle miscellaneous cases, the strings "pre", "preview", and
+    "rc" are treated as if they were "c", i.e. as though they were release
+    candidates, and therefore are not as new as a version string that does not
+    contain them, and "dev" is replaced with an '@' so that it sorts lower than
+    than any other pre-release tag.
+    """
+    parts = []
+    for part in _parse_version_parts(s.lower()):
+        if part.startswith('*'):
+            if part<'*final':   # remove '-' before a prerelease tag
+                while parts and parts[-1]=='*final-': parts.pop()
+            # remove trailing zeros from each series of numeric parts
+            while parts and parts[-1]=='00000000':
+                parts.pop()
+        parts.append(part)
+    return tuple(parts)