- rename check_provision() to split_revision()

- fix indentation to conform to the Python style guide
- add more tests and documentation

2 files changed, 145 insertions, 88 deletions

diff --git a/Lib/distutils/dist.py b/Lib/distutils/dist.py
index c5dd5cb..f015874 100644
--- a/Lib/distutils/dist.py
+++ b/Lib/distutils/dist.py
@@ -1181,11 +1181,7 @@ class DistributionMetadata:
         value = [v.strip() for v in value]
         for v in value:
             import distutils.versionpredicate
-            ver = distutils.versionpredicate.check_provision(v)
-            if ver:
-                import distutils.version
-                sv = distutils.version.StrictVersion()
-                sv.parse(ver.strip()[1:-1])
+            distutils.versionpredicate.split_provision(v)
         self.provides = value
 
     def get_obsoletes(self):
diff --git a/Lib/distutils/versionpredicate.py b/Lib/distutils/versionpredicate.py
index 5126ebf..8922b13 100644
--- a/Lib/distutils/versionpredicate.py
+++ b/Lib/distutils/versionpredicate.py
@@ -1,9 +1,10 @@
 """Module for parsing and testing package version predicate strings.
 """
 import re
-import version
+import distutils.version
 import operator
 
+
 re_validPackage = re.compile(r"(?i)^\s*([a-z_]\w*(?:\.[a-z_]\w*)*)(.*)")
 # (package) (rest)
 
@@ -11,93 +12,153 @@ re_paren = re.compile(r"^\s*\((.*)\)\s*$") # (list) inside of parentheses
 re_splitComparison = re.compile(r"^\s*(<=|>=|<|>|!=|==)\s*([^\s,]+)\s*$")
 # (comp) (version)
 
+
 def splitUp(pred):
-   """Parse a single version comparison.
-   Return (comparison string, StrictVersion)
-   """
-   res = re_splitComparison.match(pred)
-   if not res:
-       raise ValueError, "Bad package restriction syntax:  " + pred
-   comp, verStr = res.groups()
-   return (comp, version.StrictVersion(verStr))
+    """Parse a single version comparison.
+
+    Return (comparison string, StrictVersion)
+    """
+    res = re_splitComparison.match(pred)
+    if not res:
+        raise ValueError("bad package restriction syntax: %r" % pred)
+    comp, verStr = res.groups()
+    return (comp, distutils.version.StrictVersion(verStr))
 
 compmap = {"<": operator.lt, "<=": operator.le, "==": operator.eq,
            ">": operator.gt, ">=": operator.ge, "!=": operator.ne}
 
 class VersionPredicate:
-   """Parse and test package version predicates.
-
-   >>> v = VersionPredicate("pyepat.abc (>1.0, <3333.3a1, !=1555.1b3)")
-   >>> print v
-   pyepat.abc (> 1.0, < 3333.3a1, != 1555.1b3)
-   >>> v.satisfied_by("1.1")
-   True
-   >>> v.satisfied_by("1.4")
-   True
-   >>> v.satisfied_by("1.0")
-   False
-   >>> v.satisfied_by("4444.4")
-   False
-   >>> v.satisfied_by("1555.1b3")
-   False
-   >>> v = VersionPredicate("pat( ==  0.1  )  ")
-   >>> v.satisfied_by("0.1")
-   True
-   >>> v.satisfied_by("0.2")
-   False
-   >>> v = VersionPredicate("p1.p2.p3.p4(>=1.0, <=1.3a1, !=1.2zb3)")
-   Traceback (most recent call last):
-   ...
-   ValueError: invalid version number '1.2zb3'
-
-   """
-
-   def __init__(self, versionPredicateStr):
-       """Parse a version predicate string.
-       """
-       # Fields:
-       #    name:  package name
-       #    pred:  list of (comparison string, StrictVersion)
-
-       versionPredicateStr = versionPredicateStr.strip()
-       if not versionPredicateStr:
-           raise ValueError, "Empty package restriction"
-       match = re_validPackage.match(versionPredicateStr)
-       if not match:
-           raise ValueError, "Bad package name in " + versionPredicateStr
-       self.name, paren = match.groups()
-       paren = paren.strip()
-       if paren:
-           match = re_paren.match(paren)
-           if not match:
-               raise ValueError, "Expected parenthesized list: " + paren
-           str = match.groups()[0]
-           self.pred = [splitUp(aPred) for aPred in str.split(",")]
-           if not self.pred:
-               raise ValueError("Empty Parenthesized list in %r" 
-                                % versionPredicateStr )
-       else:
-           self.pred=[]
-
-   def __str__(self):
-       if self.pred:
-           seq = [cond + " " + str(ver) for cond, ver in self.pred]
-           return self.name + " (" + ", ".join(seq) + ")"
-       else:
-           return self.name
-
-   def satisfied_by(self, version):
-       """True if version is compatible with all the predicates in self.
-          The parameter version must be acceptable to the StrictVersion
-          constructor.  It may be either a string or StrictVersion.
-       """
-       for cond, ver in self.pred:
-           if not compmap[cond](version, ver):
-               return False
-       return True
-
-
-def check_provision(value):
-    m = re.match("[a-zA-Z_]\w*(\.[a-zA-Z_]\w*)*(\s*\([^)]+\))?$", value)
+    """Parse and test package version predicates.
+
+    >>> v = VersionPredicate('pyepat.abc (>1.0, <3333.3a1, !=1555.1b3)')
+
+    The `name` attribute provides the full dotted name that is given::
+
+    >>> v.name
+    'pyepat.abc'
+
+    The str() of a `VersionPredicate` provides a normalized
+    human-readable version of the expression::
+
+    >>> print v
+    pyepat.abc (> 1.0, < 3333.3a1, != 1555.1b3)
+
+    The `satisfied_by()` method can be used to determine with a given
+    version number is included in the set described by the version
+    restrictions::
+
+    >>> v.satisfied_by('1.1')
+    True
+    >>> v.satisfied_by('1.4')
+    True
+    >>> v.satisfied_by('1.0')
+    False
+    >>> v.satisfied_by('4444.4')
+    False
+    >>> v.satisfied_by('1555.1b3')
+    False
+
+    `VersionPredicate` is flexible in accepting extra whitespace::
+
+    >>> v = VersionPredicate(' pat( ==  0.1  )  ')
+    >>> v.name
+    'pat'
+    >>> v.satisfied_by('0.1')
+    True
+    >>> v.satisfied_by('0.2')
+    False
+
+    If any version numbers passed in do not conform to the
+    restrictions of `StrictVersion`, a `ValueError` is raised::
+
+    >>> v = VersionPredicate('p1.p2.p3.p4(>=1.0, <=1.3a1, !=1.2zb3)')
+    Traceback (most recent call last):
+      ...
+    ValueError: invalid version number '1.2zb3'
+
+    It the module or package name given does not conform to what's
+    allowed as a legal module or package name, `ValueError` is
+    raised::
+
+    >>> v = VersionPredicate('foo-bar')
+    Traceback (most recent call last):
+      ...
+    ValueError: expected parenthesized list: '-bar'
+
+    >>> v = VersionPredicate('foo bar (12.21)')
+    Traceback (most recent call last):
+      ...
+    ValueError: expected parenthesized list: 'bar (12.21)'
+
+    """
+
+    def __init__(self, versionPredicateStr):
+        """Parse a version predicate string.
+        """
+        # Fields:
+        #    name:  package name
+        #    pred:  list of (comparison string, StrictVersion)
+
+        versionPredicateStr = versionPredicateStr.strip()
+        if not versionPredicateStr:
+           raise ValueError("empty package restriction")
+        match = re_validPackage.match(versionPredicateStr)
+        if not match:
+           raise ValueError("bad package name in %r" % versionPredicateStr)
+        self.name, paren = match.groups()
+        paren = paren.strip()
+        if paren:
+            match = re_paren.match(paren)
+            if not match:
+                raise ValueError("expected parenthesized list: %r" % paren)
+            str = match.groups()[0]
+            self.pred = [splitUp(aPred) for aPred in str.split(",")]
+            if not self.pred:
+                raise ValueError("empty parenthesized list in %r" 
+                                 % versionPredicateStr)
+        else:
+            self.pred=[]
+
+    def __str__(self):
+        if self.pred:
+            seq = [cond + " " + str(ver) for cond, ver in self.pred]
+            return self.name + " (" + ", ".join(seq) + ")"
+        else:
+            return self.name
+
+    def satisfied_by(self, version):
+        """True if version is compatible with all the predicates in self.
+        The parameter version must be acceptable to the StrictVersion
+        constructor.  It may be either a string or StrictVersion.
+        """
+        for cond, ver in self.pred:
+            if not compmap[cond](version, ver):
+                return False
+        return True
+
+
+_provision_rx = None
+
+def split_provision(value):
+    """Return the name and optional version number of a provision.
+
+    The version number, if given, will be returned as a `StrictVersion`
+    instance, otherwise it will be `None`.
+
+    >>> split_provision('mypkg')
+    ('mypkg', None)
+    >>> split_provision(' mypkg( 1.2 ) ')
+    ('mypkg', StrictVersion ('1.2'))
+    """
+    global _provision_rx
+    if _provision_rx is None:
+        _provision_rx = re.compile(
+            "([a-zA-Z_]\w*(?:\.[a-zA-Z_]\w*)*)(?:\s*\(\s*([^)\s]+)\s*\))?$")
+    value = value.strip()
+    m = _provision_rx.match(value)
     if not m:
         raise ValueError("illegal provides specification: %r" % value)
+    ver = m.group(2) or None
+    if ver:
+        ver = distutils.version.StrictVersion(ver)
+    return m.group(1), ver