Rough draft of version requirement parser. Make bdist_egg look for a

distname.egg-info directory instead of EGG-INFO.in; this will be used later
to support development of egg-distributed packages that an application
under development expects to 'require()'.  (Thanks to Fred Drake for
pointing out this use case, and Bob Ippolito for helping me figure out how
to support it, although the runtime support doesn't actually exist yet.)

--HG--
branch : setuptools
extra : convert_revision : svn%3A6015fed2-1504-0410-9fe1-9d1591cc4771/sandbox/trunk/setuptools%4040999

1 files changed, 281 insertions, 75 deletions

diff --git a/pkg_resources.py b/pkg_resources.py
index 08b75362..17dc23df 100644
--- a/pkg_resources.py
+++ b/pkg_resources.py
@@ -13,23 +13,14 @@ The package resource API is designed to work with normal filesystem packages,
 .zip files and with custom PEP 302 loaders that support the ``get_data()``
 method.
 """
-
-import sys
-import os
-import time
-import zipimport
-try:
-    from cStringIO import StringIO
-except ImportError:
-    from StringIO import StringIO
-
 __all__ = [
     'register_loader_type', 'get_provider', 'IResourceProvider',
     'ResourceManager', 'iter_distributions', 'require', 'resource_string',
     'resource_stream', 'resource_filename', 'set_extraction_path',
-    'cleanup_resources', # 'glob_resources'
+    'cleanup_resources', 'parse_requirements', # 'glob_resources'
 ]
 
+import sys, os, zipimport, time, re
 _provider_factories = {}
 
 def register_loader_type(loader_type, provider_factory):
@@ -41,7 +32,6 @@ def register_loader_type(loader_type, provider_factory):
     """
     _provider_factories[loader_type] = provider_factory
 
-
 def get_provider(moduleName):
     """Return an IResourceProvider for the named module"""
     module = sys.modules[moduleName]
@@ -50,6 +40,7 @@ def get_provider(moduleName):
 
 
 class IResourceProvider:
+
     """An object that provides access to package resources"""
 
     def get_resource_filename(manager, resource_name):
@@ -77,13 +68,18 @@ class IResourceProvider:
         """The named metadata resource as a string"""
 
     def get_metadata_lines(name):
-        """The named metadata resource as a filtered iterator of
-        stripped (of # comments and whitespace) lines
-        """
+        """Yield named metadata resource as list of non-blank non-comment lines
+
+       Leading and trailing whitespace is stripped from each line, and lines
+       with ``#`` as the first non-blank character are omitted.
+       """
 
     # XXX list_resources?  glob_resources?
 
 
+
+
+
 class ResourceManager:
     """Manage resource extraction and packages"""
 
@@ -98,18 +94,32 @@ class ResourceManager:
 
     def resource_filename(self, package_name, resource_name):
         """Return a true filesystem path for specified resource"""
-        return get_provider(package_name).get_resource_filename(self,
-            resource_name)
+        return get_provider(package_name).get_resource_filename(self,resource_name)
 
     def resource_stream(self, package_name, resource_name):
         """Return a readable file-like object for specified resource"""
-        return get_provider(package_name).get_resource_stream(self,
-            resource_name)
+        return get_provider(package_name).get_resource_stream(self,resource_name)
 
     def resource_string(self, package_name, resource_name):
         """Return specified resource as a string"""
-        return get_provider(package_name).get_resource_string(self,
-            resource_name)
+        return get_provider(package_name).get_resource_string(self,resource_name)
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
 
     def get_cache_path(self, archive_name, names=()):
         """Return absolute location in cache for `archive_name` and `names`
@@ -131,23 +141,6 @@ class ResourceManager:
         self.cached_files.append(target_path)
         return target_path
 
-    def require(self, requirement, path=None):
-        """Ensure a distribution matching `requirement` is on ``sys.path``
-
-        The `requirement` and `path` arguments are the same as for
-        the ``iter_distributions()`` method, but `requirement` is not optional
-        for `require`, since you must specify the desired distribution name.
-        """
-        for dist in self.iter_distributions(requirement, path):
-            dist.require()
-            return
-        else:
-            pass
-            #raise ImportError(
-            #    "No distributions found matching " + repr(requirement)
-            #)
-
-    # XXX Not yet implemented
 
     def postprocess(self, filename):
         """Perform any platform-specific postprocessing of file `filename`
@@ -155,24 +148,19 @@ class ResourceManager:
         This is where Mac header rewrites should be done; other platforms don't
         have anything special they should do.
 
-        Resource providers should call this method after successfully
-        extracting a compressed resource.  They should not call it on resources
+        Resource providers should call this method ONLY after successfully
+        extracting a compressed resource.  They must NOT call it on resources
         that are already in the filesystem.
         """
         # XXX
-        # print "postprocessing", filename     
 
-    def iter_distributions(self, requirement=None, path=None):
-        """Iterate over distributions in `path` matching `requirement`
 
-        The `path` is a sequence of ``sys.path`` items.  If not supplied,
-        ``sys.path`` is used.
 
-        The `requirement` is an optional string specifying the name of the
-        desired distribution.
-        """
-        # XXX
-        return ()
+
+
+
+
+
 
     def set_extraction_path(self, path):
         """Set the base path where resources will be extracted to, if needed.
@@ -207,9 +195,96 @@ class ResourceManager:
         directory used for extractions.
         """
         # XXX
-        pass
 
 
+
+
+
+
+
+
+def iter_distributions(requirement=None, path=None):
+    """Iterate over distributions in `path` matching `requirement`
+
+    The `path` is a sequence of ``sys.path`` items.  If not supplied,
+    ``sys.path`` is used.
+
+    The `requirement` is an optional string specifying the name of the
+    desired distribution.
+    """
+    if path is None:
+        path = sys.path
+
+    if requirement is not None:
+        requirements = list(parse_requirements(requirement))
+        try:
+            requirement, = requirements
+        except ValueError:
+            raise ValueError("Must specify exactly one requirement")
+
+    for item in path:
+        source = get_dist_source(item)
+        for dist in source.iter_distributions(requirement):
+            yield dist
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+def require(*requirements):
+    """Ensure that distributions matching `requirements` are on ``sys.path``
+
+    `requirements` must be a string or a (possibly-nested) sequence
+    thereof, specifying the distributions and versions required.
+    XXX THIS IS DRAFT CODE FOR DESIGN PURPOSES ONLY RIGHT NOW
+    """
+    all_distros = {}
+    installed = {}
+    for dist in iter_distributions():
+        key = dist.name.lower()
+        all_distros.setdefault(key,[]).append(dist)
+        if dist.installed():
+            installed[key] = dist   # XXX what if more than one on path?
+
+    all_requirements = {}
+
+    def _require(requirements,source=None):
+        for req in parse_requirements(requirements):
+            name,vers = req # XXX
+            key = name.lower()
+            all_requirements.setdefault(key,[]).append((req,source))
+            if key in installed and not req.matches(installed[key]):
+                raise ImportError(
+                    "The installed %s distribution does not match"  # XXX
+                )   # XXX should this be a subclass of ImportError?
+            all_distros[key] = distros = [
+                dist for dist in all_distros.get(key,[])
+                if req.matches(dist)
+            ]
+            if not distros:
+                raise ImportError(
+                    "No %s distribution matches all criteria for " % name
+                )   # XXX should this be a subclass of ImportError?
+        for key in all_requirements.keys(): # XXX sort them
+            pass
+            # find "best" distro for key and install it
+            # after _require()-ing its requirements
+        
+    _require(requirements)
+        
 class DefaultProvider:
     """Provides access to package resources in the filesystem"""
 
@@ -243,10 +318,13 @@ class DefaultProvider:
         return self._get(os.path.join(self.egg_info, *name.split('/')))
 
     def get_metadata_lines(self, name):
-        for line in self.get_metadata(name).splitlines():
-            line = line.strip()
-            if not line.startswith('#'):
-                yield line
+        return yield_lines(self.get_metadata(name))
+
+
+
+
+
+
 
     def _has(self, path):
         return os.path.exists(path)
@@ -265,6 +343,7 @@ class DefaultProvider:
 register_loader_type(type(None), DefaultProvider)
 
 
+
 class NullProvider(DefaultProvider):
     """Try to implement resource support for arbitrary PEP 302 loaders"""
 
@@ -274,33 +353,36 @@ class NullProvider(DefaultProvider):
         )
 
     def _get(self, path):
-        get_data = getattr(self.loader, 'get_data', None)
-        if get_data is None:
-            raise NotImplementedError(
-                "Can't perform this operation for loaders without 'get_data()'"
-            )
-        return get_data(path)
+        if hasattr(self.loader, 'get_data'):
+            return self.loader.get_data(path)
+        raise NotImplementedError(
+            "Can't perform this operation for loaders without 'get_data()'"
+        )
 
 
 register_loader_type(object, NullProvider)
 
 
+
+
+
+
 class ZipProvider(DefaultProvider):
     """Resource support for zips and eggs"""
 
     egg_name = None
-    eagers = None
+    eagers   = None
 
     def __init__(self, module):
         self.module = module
         self.loader = module.__loader__
         self.zipinfo = zipimport._zip_directory_cache[self.loader.archive]
-        self.zip_pre = self.loader.archive + os.sep
+        self.zip_pre = self.loader.archive+os.sep
 
         path = self.module_path = os.path.dirname(module.__file__)
         old = None
         self.prefix = []
-        while path != old:
+        while path!=old:
             if path.lower().endswith('.egg'):
                 self.egg_name = os.path.basename(path)
                 self.egg_info = os.path.join(path, 'EGG-INFO')
@@ -323,22 +405,24 @@ class ZipProvider(DefaultProvider):
     def get_resource_stream(self, manager, resource_name):
         return StringIO(self.get_resource_string(manager, resource_name))
 
+
+
+
     def _extract_resource(self, manager, resource_name):
         parts = resource_name.split('/')
         zip_path = os.path.join(self.module_path, *parts)
-        zip_stat = self.zipinfo[os.path.join(*(self.prefix + parts))]
-        t, d, size = zip_stat[5], zip_stat[6], zip_stat[3]
+        zip_stat = self.zipinfo[os.path.join(*self.prefix+parts)]
+        t,d,size = zip_stat[5], zip_stat[6], zip_stat[3]
         date_time = (
-            (d >> 9) + 1980, (d >> 5) & 0xF, d & 0x1F,
-            (t & 0xFFFF) >> 11, (t >> 5) & 0x3F,
-            (t & 0x1F) * 2, 0, 0, -1
+            (d>>9)+1980, (d>>5)&0xF, d&0x1F,                      # ymd
+            (t&0xFFFF)>>11, (t>>5)&0x3F, (t&0x1F) * 2, 0, 0, -1   # hms, etc.
         )
         timestamp = time.mktime(date_time)
-        real_path = manager.get_cache_path(self.egg_name, self.prefix + parts)
+        real_path = manager.get_cache_path(self.egg_name, self.prefix+parts)
 
         if os.path.isfile(real_path):
             stat = os.stat(real_path)
-            if stat.st_size == size and stat.st_mtime == timestamp:
+            if stat.st_size==size and stat.st_mtime==timestamp:
                 # size and stamp match, don't bother extracting
                 return real_path
 
@@ -346,7 +430,7 @@ class ZipProvider(DefaultProvider):
 
         data = self.loader.get_data(zip_path)
         open(real_path, 'wb').write(data)
-        os.utime(real_path, (timestamp, timestamp))
+        os.utime(real_path, (timestamp,timestamp))
         manager.postprocess(real_path)
         return real_path
 
@@ -359,6 +443,12 @@ class ZipProvider(DefaultProvider):
             self.eagers = eagers
         return self.eagers
 
+
+
+
+
+
+
     def get_resource_filename(self, manager, resource_name):
         if not self.egg_name:
             raise NotImplementedError(
@@ -377,14 +467,118 @@ class ZipProvider(DefaultProvider):
 register_loader_type(zipimport.zipimporter, ZipProvider)
 
 
+def StringIO(*args, **kw):
+    """Thunk to load the real StringIO on demand"""
+    global StringIO
+    try:
+        from cStringIO import StringIO
+    except ImportError:
+        from StringIO import StringIO
+    return StringIO(*args,**kw)
+
+
+def get_distro_source(path_item):
+    pass    # XXX
+
+
+
+
+
+
+
+
+
+
+
+def yield_lines(strs):
+    """Yield non-empty/non-comment lines of a ``basestring`` or sequence"""
+    if isinstance(strs,basestring):
+        for s in strs.splitlines():
+            s = s.strip()
+            if s and not s.startswith('#'):     # skip blank lines/comments
+                yield s
+    else:
+        for ss in strs:
+            for s in yield_lines(ss):
+                yield s
+
+LINE_END = re.compile(r"\s*(#.*)?$").match         # whitespace and comment
+CONTINUE = re.compile(r"\s*\\\s*(#.*)?$").match    # line continuation
+DISTRO   = re.compile(r"\s*(\w+)").match           # Distribution name
+VERSION  = re.compile(r"\s*(<=?|>=?|==|!=)\s*((\w|\.)+)").match  # version info
+COMMA    = re.compile(r"\s*,").match               # comma between items
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+def parse_requirements(strs):
+    """Yield ``Requirement`` objects for each specification in `strs`
+
+    `strs` must be an instance of ``basestring``, or a (possibly-nested)
+    sequence thereof.
+    """
+    # create a steppable iterator, so we can handle \-continuations
+    lines = iter(yield_lines(strs))
+    for line in lines:
+        line = line.replace('-','_')
+        match = DISTRO(line)
+        if not match:
+            raise ValueError("Missing distribution spec", line)
+        distname = match.group(1)
+        p = match.end()
+        specs = []
+        while not LINE_END(line,p):
+            if CONTINUE(line,p):
+                try:
+                    line = lines.next().replace('-','_'); p = 0
+                except StopIteration:
+                    raise ValueError(
+                        "\\ must not appear on the last nonblank line"
+                    )
+            match = VERSION(line,p)
+            if not match:
+                raise ValueError("Expected version spec in",line,"at",line[p:])
+            specs.append(match.group(1,2))
+            p = match.end()
+            match = COMMA(line,p)
+            if match:
+                p = match.end() # skip the comma
+            elif not LINE_END(line,p):
+                raise ValueError("Expected ',' or EOL in",line,"at",line[p:])
+
+        yield distname, specs
+
+
+
+
+
 def _get_mro(cls):
     """Get an mro for a type or classic class"""
-    if not isinstance(cls, type):
-        cls = type('', (cls, object), {})
+    if not isinstance(cls,type):
+        class cls(cls,object): pass
         return cls.__mro__[1:]
     return cls.__mro__
 
-
 def _find_adapter(registry, ob):
     """Return an adapter factory for `ob` from `registry`"""
     for t in _get_mro(getattr(ob, '__class__', type(ob))):
@@ -407,3 +601,15 @@ def _initialize(g):
         if not name.startswith('_'):
             g[name] = getattr(_manager, name)
 _initialize(globals())
+
+
+
+
+
+
+
+
+
+
+
+